Pin mesh-sdk 05b3e2e1b94f, mesh-contracts ae5266e77639 and mesh-catalog's buildstep 125929dbc459, the group's final heads (issue 1966)

Claude-Session: https://claude.ai/code/session_01JG73KJNrH5EgFXMKKYSrig

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/asks.go

@@ -1,161 +0,0 @@
-package main
-
-import (
-	"context"
-	"sort"
-	"strings"
-	"sync"
-	"time"
-
-	"git.novox.be/novox/mesh-sdk/go/buildstep"
-	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
-
-	"mesh-delivery-assigner/internal/assign"
-)
-
-// AssignerModule is the asker the assigner's compose asks name.
-const AssignerModule = "mesh-delivery-assigner"
-
-// composeAsks are the compose asks the assigner put on the Go build seat's check stream (novox/hq ADR 0482 clause 4,
-// issues 1622 and 1623), by what each composes: one ask per key, put once and followed by a watch of its step key until
-// it ends, which wakes a pass. No timer: an ask that waits in the stream waits (its backlog is the view's and the
-// watchman's to show). A restart forgets them and asks again; the build module keeps a composer built for a commit, so a
-// second ask builds nothing.
-type composeAsks struct {
-	ctx   context.Context
-	asker buildrun.Asker
-	wake  func()
-	logf  func(string, ...any)
-	now   func() time.Time
-
-	mu   sync.Mutex
-	asks map[string]*composeAsk
-}
-
-type composeAsk struct {
-	id     string
-	cancel context.CancelFunc
-	ran    *assign.Ran
-}
-
-func newComposeAsks(ctx context.Context, asker buildrun.Asker, wake func(), logf func(string, ...any)) *composeAsks {
-	return &composeAsks{ctx: ctx, asker: asker, wake: wake, logf: logf, now: time.Now, asks: map[string]*composeAsk{}}
-}
-
-// get is the end of the ask that composes key, or nil and its id while it runs. The first get of a key puts the ask.
-// A job its layout refuses ends at once, failed with why: never silent.
-func (a *composeAsks) get(key string, job delivery.ComposeJob) (*assign.Ran, string) {
-	a.mu.Lock()
-	defer a.mu.Unlock()
-	if k, ok := a.asks[key]; ok {
-		return k.ran, k.id
-	}
-	ask := delivery.StepAsk{ID: buildstep.NewID(), Kind: delivery.AskCheck, Language: delivery.AskGo, Asker: AssignerModule,
-		At: a.now(), Compose: &job}
-	ctx, cancel := context.WithCancel(a.ctx)
-	k := &composeAsk{id: ask.ID, cancel: cancel}
-	a.asks[key] = k
-	if err := a.asker.Put(ctx, ask); err != nil {
-		a.logf("the compose ask %s for %s could not be put: %v", ask.ID, key, err)
-		k.ran = &assign.Ran{State: delivery.StepFailed, Reason: "the compose ask could not be put on the Go build seat: " + err.Error()}
-		cancel()
-		return k.ran, k.id
-	}
-	go func() {
-		step, err := a.asker.Wait(ctx, ask)
-		if ctx.Err() != nil {
-			return
-		}
-		ran := assign.RanOf(step)
-		if err != nil {
-			ran = assign.Ran{State: delivery.StepFailed, Reason: "the compose ask's step could not be followed: " + err.Error()}
-		}
-		a.mu.Lock()
-		k.ran = &ran
-		a.mu.Unlock()
-		a.wake()
-	}()
-	return nil, k.id
-}
-
-// sweep forgets, and stops following, every ask whose key no pass asked for this time: a candidate gone or moved on.
-func (a *composeAsks) sweep(seen map[string]bool) {
-	a.mu.Lock()
-	defer a.mu.Unlock()
-	for key, k := range a.asks {
-		if !seen[key] {
-			k.cancel()
-			delete(a.asks, key)
-		}
-	}
-}
-
-// composeAtHead is the composition of a group with a mesh-sdk member: the composer at its head and at each reader's
-// mesh-sdk, asked of the Go build seat, and the verdict once every ask ended; until then the verdict waits, naming the
-// asks. The keys it used are marked in seen.
-func (p *passer) composeAtHead(ctx context.Context, m assign.Mesh, ch assign.Change, seen map[string]bool, began time.Time) delivery.CompositionVerdict {
-	waiting := func(words string) delivery.CompositionVerdict {
-		return delivery.CompositionVerdict{Group: ch.Group, Heads: ch.Heads, State: delivery.CompositionWaits, Words: words}
-	}
-	head, err := assign.HeadJob(m, ch)
-	if err != nil {
-		return delivery.CompositionVerdict{Group: ch.Group, Heads: ch.Heads, State: delivery.CompositionFail, SDK: "mesh-sdk " + ch.SDKHead,
-			Words: "the compose ask at the group's mesh-sdk head cannot be made: " + err.Error()}
-	}
-	var pending []string
-	key := "head." + ch.Group + "." + ch.Heads + "." + ch.SDKHead
-	seen[key] = true
-	headRan, id := p.asks.get(key, head)
-	if headRan == nil {
-		pending = append(pending, "mesh-sdk "+ch.SDKHead+" (ask "+id+")")
-	}
-	var readers []assign.Reader
-	var notJudged []string
-	for _, module := range sortedNames(assign.ReaderModules) {
-		repository := assign.ReaderModules[module]
-		var commits []string
-		member := false
-		if h := ch.Members[repository]; h != "" {
-			commits, member = []string{h}, true
-		} else {
-			commits = p.w.runningCommits(ctx, kvGetter(p.kvs[delivery.BuildsBucket]), module)
-		}
-		if len(commits) == 0 {
-			notJudged = append(notJudged, "not judged whether "+module+" reads the group's manifests: no build of it is assigned with a "+
-				"commit on record, and the group holds no member of "+repository)
-			continue
-		}
-		for _, commit := range commits {
-			job, err := assign.ReaderJob(ch, module, repository, commit)
-			if err != nil {
-				readers = append(readers, assign.Reader{Module: module, Commit: commit, Member: member,
-					Ran: assign.Ran{State: delivery.StepFailed, Reason: err.Error()}})
-				continue
-			}
-			rkey := "reader." + ch.Group + "." + ch.Heads + "." + module + "." + commit
-			seen[rkey] = true
-			ran, rid := p.asks.get(rkey, job)
-			if ran == nil {
-				pending = append(pending, module+" at "+commit+" (ask "+rid+")")
-				continue
-			}
-			readers = append(readers, assign.Reader{Module: module, Commit: commit, Member: member, Ran: *ran})
-		}
-	}
-	if len(pending) > 0 {
-		return waiting("composing on the Go build seat with the mesh-sdk of " + strings.Join(pending, ", "))
-	}
-	v := assign.FromComposer(m, ch, *headRan, readers, time.Since(began))
-	v.Warnings = append(v.Warnings, notJudged...)
-	return v
-}
-
-func sortedNames(m map[string]string) []string {
-	out := make([]string, 0, len(m))
-	for k := range m {
-		out = append(out, k)
-	}
-	sort.Strings(out)
-	return out
-}

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/compose_integration_test.go

@@ -1,180 +0,0 @@
-//go:build integration
-
-package main
-
-import (
-	"encoding/json"
-	"errors"
-	"strings"
-	"sync"
-	"testing"
-	"time"
-
-	"github.com/nats-io/nats.go/jetstream"
-
-	"git.novox.be/novox/mesh-sdk/go/composer"
-	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/provider"
-)
-
-// holder is a test holder of the Go build seat: it takes every ask from the seat's check worker, as mesh-build-go does,
-// and answers a compose ask by running mesh-sdk's composer over the request filled from the indexer's manifests (the
-// linked composer standing for the one the build module builds at the asked commit), writing its step on its node's key.
-type holder struct {
-	mu   sync.Mutex
-	asks []delivery.StepAsk
-}
-
-func (h *holder) taken() []delivery.StepAsk {
-	h.mu.Lock()
-	defer h.mu.Unlock()
-	return append([]delivery.StepAsk(nil), h.asks...)
-}
-
-func (b *bed) hold(t *testing.T) *holder {
-	t.Helper()
-	seat, _ := delivery.AskStream(delivery.AskGo)
-	worker, _ := delivery.AskWorker(delivery.AskGo, delivery.AskCheck)
-	subject, _ := delivery.AskSubject(delivery.AskGo, delivery.AskCheck)
-	cons, err := b.js.CreateOrUpdateConsumer(b.ctx, seat, jetstream.ConsumerConfig{Durable: worker, FilterSubject: subject, AckPolicy: jetstream.AckExplicitPolicy})
-	if err != nil {
-		t.Fatal(err)
-	}
-	steps := b.buckets[delivery.StepsBucket(goBuildModule)]
-	h := &holder{}
-	cc, err := cons.Consume(func(m jetstream.Msg) {
-		a, err := delivery.DecodeStepAsk(m.Data())
-		if err != nil || a.Compose == nil {
-			t.Errorf("the seat was put an ask that is not a compose: %v %s", err, m.Data())
-			m.Ack()
-			return
-		}
-		h.mu.Lock()
-		h.asks = append(h.asks, a)
-		h.mu.Unlock()
-		req, err := composer.Decode(a.Compose.Request)
-		if err == nil {
-			err = composer.Fill(&req, func(digest string) ([]byte, error) {
-				key, _ := delivery.ManifestsKey(digest)
-				e, err := b.buckets[delivery.ManifestsBucket].Get(b.ctx, key)
-				if err != nil {
-					return nil, err
-				}
-				man, err := delivery.DecodeManifest(e.Value())
-				return []byte(man.JSON), err
-			})
-		}
-		step := delivery.Step{ID: a.ID, Tool: "compose", Node: "ace", State: delivery.StepPassed, Started: time.Now().UTC(), Ended: time.Now().UTC()}
-		if err != nil {
-			step.State, step.Reason = delivery.StepFailed, err.Error()
-		} else if v, err := composer.Run(req); err != nil {
-			step.State, step.Reason = delivery.StepFailed, err.Error()
-		} else {
-			vr, _ := json.Marshal(v)
-			step.Result, _ = json.Marshal(delivery.ComposeAnswer{Built: true, Key: "composer-0123456789abcdef", Verdict: vr})
-		}
-		raw, err := delivery.EncodeStep(step)
-		if err != nil {
-			t.Errorf("the step cannot be written: %v", err)
-		}
-		key, _ := delivery.AskStepKey("ace", a.ID)
-		if _, err := steps.Put(b.ctx, key, raw); err != nil {
-			t.Errorf("the step %s: %v", key, err)
-		}
-		m.Ack()
-	})
-	if err != nil {
-		t.Fatal(err)
-	}
-	t.Cleanup(cc.Stop)
-	return h
-}
-
-// 1622/AC1-AC3 and 1623 on the bus: started whole, the assigner composes a group holding a mesh-sdk pull request by
-// asking the Go build seat for the composer at the member's head, and for the composer at the mesh-sdk the running
-// controller pins; it waits naming the asks while they run, writes the verdict from their answers naming the mesh-sdk the
-// head's composer was built with, and asks nothing more on a later pass of the same heads.
-func TestAGroupWithAnSDKMemberIsComposedByTheComposerAtItsHead(t *testing.T) {
-	b := startBed(t, "")
-	trunk := b.manifest(t, "web", `{"module":"web","version":"1"}`)
-	changed := b.manifest(t, "web", `{"module":"web","version":"2"}`)
-	mod, err := delivery.EncodeModule(delivery.Module{FP2: delivery.SourcePrefix2 + strings.Repeat("a", 64), Manifest: trunk, Repository: "novox/web", Commit: strings.Repeat("1", 40), Path: delivery.RootPath})
-	if err != nil {
-		t.Fatal(err)
-	}
-	b.putJSON(t, delivery.ModulesBucket, "web", mod)
-	b.putJSON(t, provider.AssignmentsBucket, "g14.web", []byte(`{"node":"g14","module":"web","build":"build-1"}`))
-	running := strings.Repeat("3", 40)
-	b.putJSON(t, provider.AssignmentsBucket, "novox.mesh-controller", []byte(`{"node":"novox","module":"mesh-controller","build":"c-1"}`))
-	b.putJSON(t, delivery.BuildsBucket, delivery.BuildKey("mesh-controller", "c-1"), []byte(`{"id":"c-1","repository":"novox/mesh-controller","commit":"`+running+`"}`))
-	sdkHead := strings.Repeat("4", 40)
-	heads := []delivery.Head{{Repository: "novox/mesh-sdk", Number: 80, Head: sdkHead}, {Repository: "novox/web", Number: 7, Head: strings.Repeat("2", 40)}}
-	hash, _ := delivery.HeadsHash(heads)
-	pulls := []delivery.CandidatePull{{Head: heads[0]}, {Head: heads[1],
-		Modules: []string{"web"}, Fps: map[string]delivery.CandidateModule{"web": {FP2: delivery.SourcePrefix2 + strings.Repeat("b", 64), Manifest: changed}}}}
-	cand, err := delivery.EncodeCandidate(delivery.Candidate{Group: "feat/x", HeadsHash: hash, Pulls: pulls, FPSet: delivery.FingerprintSet(pulls)})
-	if err != nil {
-		t.Fatal(err)
-	}
-	ckey, _ := delivery.CandidatesKey("feat/x")
-	b.putJSON(t, delivery.CandidatesBucket, ckey, cand)
-	b.start(t)
-	key, _ := delivery.CompositionKey("feat/x", hash)
-	// No holder takes the asks yet: the composition waits, naming them.
-	waits := b.verdict(t, key, func(v delivery.CompositionVerdict) bool { return v.State == delivery.CompositionWaits })
-	if !strings.Contains(waits.Words, "mesh-sdk "+sdkHead) || !strings.Contains(waits.Words, "mesh-controller at "+running) {
-		t.Fatalf("the waiting composition says %q, want the head's and the running controller's asks", waits.Words)
-	}
-	h := b.hold(t)
-	v := b.verdict(t, key, func(v delivery.CompositionVerdict) bool { return v.State != delivery.CompositionWaits })
-	if v.State != delivery.CompositionPass || len(v.Machines) != 1 || v.Machines[0] != "g14" || v.SDK == "" {
-		t.Fatalf("composition = %+v, want a pass on g14", v)
-	}
-	asks := h.taken()
-	if len(asks) != 2 {
-		t.Fatalf("the seat was asked %d composes, want two (the head, the running controller)", len(asks))
-	}
-	byRepo := map[string]delivery.StepAsk{}
-	for _, a := range asks {
-		byRepo[a.Compose.Fetch["repository"].(string)] = a
-		if a.Asker != AssignerModule || a.Kind != delivery.AskCheck || a.Language != delivery.AskGo {
-			t.Errorf("ask = %+v", a)
-		}
-	}
-	if a := byRepo["novox/mesh-sdk"]; a.Compose == nil || a.Compose.Fetch["commit"] != sdkHead || a.Compose.Dir != "go" {
-		t.Errorf("the head's ask = %+v", a.Compose)
-	}
-	if a := byRepo["novox/mesh-controller"]; a.Compose == nil || a.Compose.Fetch["commit"] != running || a.Compose.Dir != delivery.RootPath {
-		t.Errorf("the running controller's ask = %+v", a.Compose)
-	}
-	// A later pass of the same heads (woken by any change) asks nothing more.
-	on, _ := delivery.EncodePresence(delivery.Presence{Online: true})
-	b.putJSON(t, delivery.PresenceBucket, "ace", on)
-	time.Sleep(500 * time.Millisecond)
-	if n := len(h.taken()); n != 2 {
-		t.Errorf("a later pass of the same heads asked again: %d asks", n)
-	}
-}
-
-// verdict waits for the composition under key to satisfy ok, and answers it.
-func (b *bed) verdict(t *testing.T, key string, ok func(delivery.CompositionVerdict) bool) delivery.CompositionVerdict {
-	t.Helper()
-	var last delivery.CompositionVerdict
-	for deadline := time.Now().Add(10 * time.Second); time.Now().Before(deadline); time.Sleep(50 * time.Millisecond) {
-		e, err := b.buckets[delivery.AssignerCompositionsBucket].Get(b.ctx, key)
-		if errors.Is(err, jetstream.ErrKeyNotFound) {
-			continue
-		}
-		if err != nil {
-			t.Fatal(err)
-		}
-		if last, err = delivery.DecodeCompositionVerdict(e.Value()); err != nil {
-			t.Fatal(err)
-		}
-		if ok(last) {
-			return last
-		}
-	}
-	t.Fatalf("no composition under %s as wanted after 10 s; last %+v", key, last)
-	return last
-}

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/composed.go

@@ -0,0 +1,73 @@
+package main
+
+import (
+	"sort"
+	"strings"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// Every node's published compositions, read only to compare (novox/hq ADR 0593 §8): each node's engine writes its own
+// `composed-<node>` (delivery.ComposedRead, one bucket per node), and `mesh-wants.upgrade` with compare names, for every
+// node, the composition its own have runs beside the newest it published of each module and of the node, so a person sees
+// where they part. The assigner composes nothing and never writes these.
+
+// publishedRow is one composition a node published: the module ("node" for its own), the fingerprint, the digest, or why
+// it was refused or cannot be read.
+type publishedRow struct {
+	Key     string `json:"key"`
+	Module  string `json:"module"`
+	FP      string `json:"fp,omitempty"`
+	Digest  string `json:"digest,omitempty"`
+	Refused string `json:"refused,omitempty"`
+	Unread  string `json:"unread,omitempty"`
+}
+
+// published is, by node, every composition it published, sorted by key, from every key of the per-node state (a key
+// names its node first): each value decoded and digested here, as the node-engine digests it (delivery.ComposedDigestOf).
+// A value or key that does not read is named with why, never left out.
+func published(values map[string][]byte) map[string][]publishedRow {
+	byNode := map[string]map[string][]byte{}
+	for key, raw := range values {
+		node, _, _ := strings.Cut(key, ".")
+		if byNode[node] == nil {
+			byNode[node] = map[string][]byte{}
+		}
+		byNode[node][key] = raw
+	}
+	out := map[string][]publishedRow{}
+	for node, keys := range byNode {
+		var rows []publishedRow
+		for key, raw := range keys {
+			row := publishedRow{Key: key}
+			_, module, fp, isNode, err := delivery.ParseComposedKey(key)
+			switch {
+			case err != nil:
+				row.Unread = err.Error()
+			case isNode:
+				row.Module = "node"
+			default:
+				row.Module, row.FP = module, fp
+			}
+			if err == nil {
+				c, derr := delivery.DecodeComposed(raw)
+				switch {
+				case derr != nil:
+					row.Unread = derr.Error()
+				case c.Refused != "":
+					row.Refused = c.Refused
+				default:
+					if d, err := delivery.ComposedDigestOf(c); err != nil {
+						row.Unread = err.Error()
+					} else {
+						row.Digest = d
+					}
+				}
+			}
+			rows = append(rows, row)
+		}
+		sort.Slice(rows, func(i, j int) bool { return rows[i].Key < rows[j].Key })
+		out[node] = rows
+	}
+	return out
+}

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/main.go

@@ -8,6 +8,7 @@ package main
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"log"
@@ -20,13 +21,18 @@ import (
 	"github.com/nats-io/nats.go"
 	"github.com/nats-io/nats.go/jetstream"
 
+	occ "git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient"
+	oc "git.novox.be/novox/mesh-contracts/go/seats/operatorchannel"
 	"git.novox.be/novox/mesh-sdk/go/announce"
-	"git.novox.be/novox/mesh-sdk/go/asks"
-	"git.novox.be/novox/mesh-sdk/go/buscompose"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
+	"git.novox.be/novox/mesh-sdk/go/health"
 	"git.novox.be/novox/mesh-sdk/go/process"
-	"git.novox.be/novox/mesh-sdk/go/provider"
+	"git.novox.be/novox/mesh-sdk/go/provisions"
+
+	"git.novox.be/novox/mesh-delivery/sdk/enginereads"
+	"git.novox.be/novox/mesh-sdk/go/views"
+
+	"mesh-delivery-assigner/internal/assign"
 )
 
 func main() {
@@ -50,30 +56,33 @@ func main() {
 // readBuckets are the buckets of other parts the assigner reads, each named in its manifest's reads (the manifest test
 // holds the two lists equal), so the controller's broker grants exactly these.
 var readBuckets = []string{
-	buscompose.ResolvedBucket,
-	provider.AssignmentsBucket,
-	delivery.BuildsBucket,
-	delivery.ControllerGrantsBucket,
-	delivery.ControllerComposedBucket,
+	delivery.PartGrantsBucket,
 	delivery.AnswersBucket,
 	delivery.BuilderBuildsBucket,
-	delivery.CandidatesBucket,
-	delivery.ManifestsBucket,
-	delivery.ModulesBucket,
 	delivery.PresenceBucket,
 	delivery.HaveBucket,
-	delivery.StepsBucket(goBuildModule),
+	provisions.ProvisionsBucket,
+	delivery.SourceBucket,
+	delivery.MergesBucket,
 }
 
-// goBuildModule is the Go build module, which takes the assigner's compose asks on its seat's check stream and writes
-// their steps in its steps state (novox/hq ADR 0482 clause 4).
-const goBuildModule = "mesh-build-go"
+// readFamilies are the states kept one bucket per node the assigner reads, each named in its manifest's reads: every
+// node's compositions, which mesh-wants.upgrade compares (novox/hq ADR 0593 §8).
+var readFamilies = []string{delivery.ComposedRead}
 
 // ownBuckets are the assigner's own states, as its manifest declares them: the seat mesh-placement's three among them
 // (ADR 0567 §1), named after the assigner as every module state is.
-var ownBuckets = []string{delivery.AssignerAsksBucket, delivery.AssignerCompositionsBucket, delivery.AssignerDifferencesBucket,
+var ownBuckets = []string{delivery.AssignerAsksBucket, delivery.AssignerDifferencesBucket,
 	delivery.AssignerPutsBucket, delivery.AssignerWantsBucket, delivery.PlacementBucket, delivery.PlacementProposalsBucket,
-	delivery.PlacementCandidatesBucket, delivery.PlacementPulsesBucket}
+	delivery.PlacementCandidatesBucket, delivery.PlacementPulsesBucket, assign.FindingsBucket, assign.PoliciesBucket, delivery.SeatHoldersBucket,
+	engineReadsBucket}
+
+// engineReadsState is the assigner's state of what each node's engine states it reads (ADR 0618 §3), one key `<node>`, as
+// the verb manifest-reads last answered it or the fallback read it: what assigner_engine_reads lists and asks again.
+const engineReadsState = "engine-reads"
+
+// engineReadsBucket is that state's bucket.
+const engineReadsBucket = delivery.AssignerModule + "_" + engineReadsState
 
 // seatBuckets are the seat's states, new with it: until the controller has made them from the manifest and the bus grants
 // them, the assigner starts without them and binds each once the bus says it was created (issue 1790's kind).
@@ -81,19 +90,25 @@ var seatBuckets = []string{delivery.PlacementBucket, delivery.PlacementProposals
 	delivery.PlacementPulsesBucket}
 
 // keptStates is what the assigner keeps and who may read it (ADR 0495 §2-§3): its wants by the watchman and the view
-// (and the node agent from release 6), its differences by the view, its compositions by the checker, its asks by the view
+// (and the node agent from release 6), its differences by the view, its asks by the view
 // and the teller, its puts by whoever follows one (ADR 0546), and the seat mesh-placement's placement, proposals and
-// candidates by the node agents, the grants part, mesh-config and the view (ADR 0567 §9).
+// candidates by the node agents, the grants part, mesh-config and the view (ADR 0567 §9), and its placement by
+// the builder, the checker and the indexer, through mesh-sdk's toolchain gate (issue 774, ADR 0549 §3).
 var keptStates = []announce.State{
 	{Name: delivery.PlacementState, Readable: true},
 	{Name: delivery.PlacementProposalsState, Readable: true},
 	{Name: delivery.PlacementCandidatesState, Readable: true},
 	{Name: delivery.PlacementPulsesState, Readable: true},
 	{Name: "asks", Readable: true},
-	{Name: "compositions", Readable: true},
 	{Name: "differences", Readable: true},
 	{Name: "puts", Readable: true},
 	{Name: "wants", Readable: true},
+	{Name: health.FindingsState, Readable: true},
+	{Name: delivery.AssignerPoliciesState, Readable: true},
+	{Name: delivery.SeatHoldersState, Readable: true},
+	{Name: views.MarksState, Readable: true},  // what its views family said each state up to (views.go)
+	{Name: views.StatusState, Readable: true}, // its first views of the indexer's states (views.go)
+	{Name: engineReadsState, Readable: true},
 }
 
 // buckets is every bucket the assigner opened, by name.
@@ -112,11 +127,51 @@ func open(ctx context.Context, js process.BucketOpener, logf func(string, ...any
 			continue
 		}
 		if slices.Contains(seatBuckets, name) && err != nil {
-			// The seat's states come in the same delivery as this assigner (ADR 0567 §1): without placement the controller's
-			// assignments alone name where modules run, as before any placement was written (ADR 0549 §5).
+			// The seat's states come in the same delivery as this assigner (ADR 0567 §1): without placement no module is placed.
 			logf("the bucket %s cannot be opened (%v): it is bound once the bus says it was made", name, err)
 			continue
 		}
+		if name == delivery.SeatHoldersBucket && err != nil {
+			// The seat's state, new with ADR 0571 §4: bound once the bus says it was made; until then nobody is told who
+			// holds which seat here, and the controller's seats still answer.
+			logf("the bucket %s cannot be opened (%v): it is bound once the bus says it was made", name, err)
+			continue
+		}
+		if name == provisions.ProvisionsBucket && err != nil {
+			// The seat mesh-provisioner's state, with its own delivery (ADR 0570 §4): bound once the bus says it was made;
+			// until then no want waits for a provision, as before.
+			logf("the bucket %s cannot be opened (%v): it is bound once the bus says it was made", name, err)
+			continue
+		}
+		if name == assign.PoliciesBucket && err != nil {
+			// The seat mesh-wants' state, new with it (ADR 0565 §7): bound once the bus says it was made; until then no
+			// person's policy is read, so the controller's beside each composition holds, as before.
+			logf("the bucket %s cannot be opened (%v): it is bound once the bus says it was made", name, err)
+			continue
+		}
+		if name == assign.FindingsBucket && err != nil {
+			// New with health leaving the controller (issue 1952 WM6): without it the conditions are said straight to the
+			// router and kept as no finding.
+			logf("the bucket %s cannot be opened (%v): the assigner's conditions are said straight to the router until it starts again", name, err)
+			continue
+		}
+		if (name == delivery.SourceBucket || name == delivery.MergesBucket) && err != nil {
+			// The gate's source and merges (ADR 0601 §1): without them no release is known to carry a build, so every move of
+			// a record module is asked of a person, as before.
+			logf("the bucket %s cannot be opened (%v): no release's Approve answers a record ask until it is bound", name, err)
+			continue
+		}
+		if name == engineReadsBucket && err != nil {
+			// New with ADR 0618 §3: without it the statements the verb answers are kept in memory only, and
+			// assigner_engine_reads lists nothing.
+			logf("the bucket %s cannot be opened (%v): what each node's engine reads is kept in memory only until it starts again", name, err)
+			continue
+		}
+		if name == delivery.PartGrantsBucket && err != nil {
+			// The grants part's grants (ADR 0571 clause 9): without them no module counts as granted until it is bound.
+			logf("the bucket %s cannot be opened (%v): no grant is read until it is bound once the bus says it was made", name, err)
+			continue
+		}
 		if err != nil {
 			return nil, process.EssentialErr("assigner", name, "write a want from the whole mesh", err)
 		}
@@ -125,6 +180,17 @@ func open(ctx context.Context, js process.BucketOpener, logf func(string, ...any
 	return out, nil
 }
 
+// startsWithout says the assigner starts without the bucket when it cannot be opened (open says why for each): the seat's
+// states and those new with a delivery of their own, bound once made, and the two that choose the grants' source.
+func startsWithout(name string) bool {
+	switch name {
+	case delivery.SeatHoldersBucket, provisions.ProvisionsBucket, assign.PoliciesBucket, assign.FindingsBucket,
+		delivery.AssignerPutsBucket, delivery.SourceBucket, delivery.MergesBucket, engineReadsBucket:
+		return true
+	}
+	return slices.Contains(seatBuckets, name) || name == delivery.PartGrantsBucket
+}
+
 // run is the program: it returns when ctx ends or the bus cannot be used.
 func run(ctx context.Context, getenv func(string) string, logOut io.Writer) error {
 	logger := log.New(logOut, "mesh-delivery-assigner: ", log.LstdFlags)
@@ -153,7 +219,40 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 	}
 	thisNode = account.Node
 	logger.Printf("started on the account %s, reading %d buckets", account.User, len(kvs))
-	return follow(ctx, js, conn, kvs, sayVia(ctx, js), emitting{said}, logger)
+	findings := findingsOf(ctx, kvs, logger.Printf)
+	// Each change of the states its readers read is said on its views family (ADR 0615 §5, ADR 0619 §2); a watch of it
+	// that ends stops the program, as a watch of what a pass reads does.
+	viewErrs := make(chan error, len(viewedStates))
+	startViews(ctx, js, conn, account, kvs, findings, viewErrs, logger.Printf)
+	go func() {
+		select {
+		case <-ctx.Done():
+		case err := <-viewErrs:
+			logger.Printf("%v: the assigner stops, and is started again", err)
+			conn.Close()
+		}
+	}()
+	iv := &indexerViews{js: js, account: account, call: said.Call, findings: findings, logf: logger.Printf,
+		status: process.AwaitBucket(ctx, js, conn, firstViewsBucket, "assigner_first_views reads nothing and assigner_first_view_again is not heard", logger.Printf)}
+	return follow(ctx, js, conn, kvs, findings.Say(sayVia(ctx, js)), findings, emitting{said}, iv, logger)
+}
+
+// findingsOf is where the assigner's said conditions go as findings (issue 1952 WM6): its findings bucket, which the
+// condition keeper carries (novox/hq ADR 0590 §3). Without it the conditions are said straight to the router.
+func findingsOf(ctx context.Context, kvs buckets, logf func(string, ...any)) assign.Findings {
+	var f assign.Findings
+	if kv := kvs[assign.FindingsBucket]; kv != nil {
+		f.Put = func(key string, value []byte) error { _, err := kv.Put(ctx, key, value); return err }
+		f.Delete = func(key string) error { return kv.Delete(ctx, key) }
+		f.Keys = func() ([]string, error) {
+			keys, err := kv.Keys(ctx)
+			if errors.Is(err, jetstream.ErrNoKeysFound) {
+				return nil, nil
+			}
+			return keys, err
+		}
+	}
+	return f
 }
 
 // thisNode is the node this process runs on, as its credential names it: said with each of the seat's events.
@@ -167,14 +266,9 @@ func (e emitting) Emit(eventType string, body any) error { return e.Conn.Emit(ev
 // watched are the buckets whose every value a pass reads; the manifests are read by digest when a pass needs one, and
 // watched only for keys, so a manifest that arrives wakes a composition that waits for it.
 var watched = []string{
-	buscompose.ResolvedBucket,
-	provider.AssignmentsBucket,
-	delivery.ControllerGrantsBucket,
-	delivery.ControllerComposedBucket,
+	delivery.PartGrantsBucket,
 	delivery.AnswersBucket,
 	delivery.BuilderBuildsBucket,
-	delivery.CandidatesBucket,
-	delivery.ModulesBucket,
 	delivery.PlacementBucket,
 	delivery.PlacementProposalsBucket,
 	delivery.PlacementCandidatesBucket,
@@ -182,14 +276,19 @@ var watched = []string{
 	delivery.PresenceBucket,
 	delivery.HaveBucket,
 	delivery.AssignerAsksBucket,
-	delivery.AssignerCompositionsBucket,
 	delivery.AssignerDifferencesBucket,
 	delivery.AssignerWantsBucket,
+	assign.PoliciesBucket,
+	provisions.ProvisionsBucket,
+	delivery.SeatHoldersBucket,
+	delivery.SourceBucket,
+	delivery.MergesBucket,
+	engineReadsBucket,
 }
 
 // follow watches every bucket a pass reads and makes a pass at start, once every watch handed what stands, and after
 // each change; changes that come during a pass make one more. It returns when ctx ends or a watch ends.
-func follow(ctx context.Context, js jetstream.JetStream, nc process.Subscriber, kvs buckets, say func(asks.Condition) error, bus caller, logger *log.Logger) error {
+func follow(ctx context.Context, js jetstream.JetStream, nc process.Subscriber, kvs buckets, say func(oc.Condition) error, findings assign.Findings, bus caller, iv *indexerViews, logger *log.Logger) error {
 	w := newWorld()
 	dirty := make(chan struct{}, 1)
 	wake := func() {
@@ -200,6 +299,16 @@ func follow(ctx context.Context, js jetstream.JetStream, nc process.Subscriber,
 	}
 	errs := make(chan error, len(watched)+2)
 	settled := make(chan struct{}, len(watched)+2)
+	// What each node's engine reads (ADR 0618 §3, §4): asked through the seat's verb, kept in the state engine-reads, read
+	// from the node's record where the engine does not answer (the fallback, said in the journal).
+	reads := &enginereads.Keeper{Fallback: w.recordReads, Changed: wake, Logf: logger.Printf}
+	if bus != nil {
+		reads.Call = bus.CallOn
+	}
+	if kv := kvs[engineReadsBucket]; kv != nil {
+		reads.Put = func(node string, v []byte) error { _, err := kv.Put(ctx, node, v); return err }
+		reads.Delete = func(node string) error { return kv.Delete(ctx, node) }
+	}
 	watch := func(name string, opts ...jetstream.WatchOpt) error {
 		kw, err := kvs[name].WatchAll(ctx, opts...)
 		if err != nil {
@@ -233,6 +342,10 @@ func follow(ctx context.Context, js jetstream.JetStream, nc process.Subscriber,
 					if e.Operation() == jetstream.KeyValuePut {
 						value = e.Value()
 					}
+					if name == engineReadsBucket {
+						reads.Heard(e.Key(), value, value == nil) // it wakes a pass when a statement changed
+						continue
+					}
 					w.putEntry(name, e.Key(), value, e.Revision(), e.Created())
 					wake()
 				}
@@ -275,35 +388,46 @@ func follow(ctx context.Context, js jetstream.JetStream, nc process.Subscriber,
 	}
 	started := 0
 	for _, name := range watched {
-		if kvs[name] == nil && slices.Contains(seatBuckets, name) {
+		if kvs[name] == nil && startsWithout(name) {
 			continue // not on the bus at this start (open said so)
 		}
 		started++
 		var opts []jetstream.WatchOpt
-		if name == delivery.HaveBucket {
-			opts = append(opts, jetstream.IncludeHistory()) // what each node ran healthy before, for a set-back
+		if name == delivery.HaveBucket || name == delivery.SourceBucket {
+			// what each node ran healthy before, for a set-back; and the release behind each source revision (ADR 0601 §1)
+			opts = append(opts, jetstream.IncludeHistory())
 		}
 		if err := watch(name, opts...); err != nil {
 			return err
 		}
 	}
-	if err := watch(delivery.ManifestsBucket, jetstream.MetaOnly()); err != nil {
-		return err
+	// The indexer's manifests, modules and module graph, through its first views and views family, never its buckets
+	// (DLV-F2r, ADR 0631): the first pass waits for the three answers, as it waits for every watch to hand what stands.
+	if iv != nil {
+		started += iv.start(ctx, w, wake, settled)
 	}
 	// The seat's states arrive with the same delivery as this assigner (ADR 0567 §1): one not on the bus at this start is
-	// bound once the bus says it was created, and watched from then on, with no restart (issue 1790's kind). Until then the
-	// controller's assignments alone name where modules run (ADR 0549 §5).
+	// bound once the bus says it was created, and watched from then on, with no restart (issue 1790's kind). Until then no
+	// module is placed.
 	type appeared struct {
 		name string
 		kv   jetstream.KeyValue
 	}
-	placementAppeared := make(chan appeared, len(seatBuckets))
+	placementAppeared := make(chan appeared, len(seatBuckets)+2)
 	for _, name := range seatBuckets {
 		if kvs[name] == nil && js != nil {
 			process.AwaitBucket(ctx, js, nc, name, "the seat mesh-placement waits for it",
 				logger.Printf).Ready(func(kv jetstream.KeyValue) { placementAppeared <- appeared{name, kv} })
 		}
 	}
+	// And the two that choose where grants are read from, with the same delivery as the grants part that writes one.
+	for _, name := range []string{delivery.PartGrantsBucket, assign.PoliciesBucket, provisions.ProvisionsBucket, delivery.SeatHoldersBucket} {
+		if kvs[name] == nil && js != nil {
+			name := name
+			process.AwaitBucket(ctx, js, nc, name, "until then the bucket is not read",
+				logger.Printf).Ready(func(kv jetstream.KeyValue) { placementAppeared <- appeared{name, kv} })
+		}
+	}
 	takePlacement := func(a appeared) error {
 		if kvs[a.name] != nil {
 			return nil // bound already, by the other of its two events
@@ -312,7 +436,7 @@ func follow(ctx context.Context, js jetstream.JetStream, nc process.Subscriber,
 		logger.Printf("the bucket %s is open and watched", a.name)
 		return watch(a.name)
 	}
-	for range started + 1 {
+	for range started {
 		select {
 		case <-ctx.Done():
 			return nil
@@ -321,8 +445,14 @@ func follow(ctx context.Context, js jetstream.JetStream, nc process.Subscriber,
 		case <-settled:
 		}
 	}
-	p := &passer{kvs: kvs, w: w, logf: logger.Printf, say: say, said: map[string]bool{}, answeredAt: map[string]uint64{}}
-	p.asks = newComposeAsks(ctx, buildrun.Asker{Publisher: buildrun.JetStreamAsks{JS: js}, Waiter: buildrun.JetStreamAsks{JS: js}}, wake, logger.Printf)
+	p := &passer{kvs: kvs, w: w, logf: logger.Printf, say: say, findings: findings, said: map[string]bool{}, answeredAt: map[string]uint64{},
+		reads: reads}
+	// The node-engine seat's manifest-reads-changed, for one node (ADR 0618 §4): that node is asked again, with no timer.
+	// Heard on the assigner's durable consumer on EVENTS, which the grants part makes from the manifest's consumes; where it
+	// is not there yet, a node is asked again only when it comes back online.
+	if js != nil {
+		hearReadsChanged(ctx, js, reads, findings, logger.Printf)
+	}
 	if bus != nil && kvs[delivery.AssignerPutsBucket] != nil {
 		p.acts = newPutActs(bus, wake, logger.Printf)
 	}
@@ -373,13 +503,13 @@ var PutsReopenEvery = time.Minute
 
 // sayVia publishes a condition on the operator-channel seat's one subject for conditions, under the assigner's own name
 // (ADR 0437 clause 9).
-func sayVia(ctx context.Context, js jetstream.JetStream) func(asks.Condition) error {
-	return func(c asks.Condition) error {
-		subject, err := asks.ConditionSubject(delivery.AssignerModule)
+func sayVia(ctx context.Context, js jetstream.JetStream) func(oc.Condition) error {
+	return func(c oc.Condition) error {
+		subject, err := occ.ConditionSubject(delivery.AssignerModule)
 		if err != nil {
 			return err
 		}
-		data, err := asks.EncodeCondition(c)
+		data, err := occ.EncodeCondition(c)
 		if err != nil {
 			return err
 		}
@@ -387,3 +517,39 @@ func sayVia(ctx context.Context, js jetstream.JetStream) func(asks.Condition) er
 		return err
 	}
 }
+
+// hearReadsChanged hears the node-engine seat's event manifest-reads-changed on the assigner's durable consumer on EVENTS,
+// and asks the node it names again. Any other event the consumer hands is acknowledged and left.
+func hearReadsChanged(ctx context.Context, js jetstream.JetStream, reads *enginereads.Keeper, findings assign.Findings, logf func(string, ...any)) {
+	account := process.Account{Node: thisNode, Module: delivery.AssignerModule}
+	w := notHeardWriter(findings, logf)
+	cons, err := account.EventConsumer(ctx, js, process.EventsStream)
+	if err != nil {
+		w.NotHeard(process.EventsStream, enginereads.Event+" is not heard until the assigner starts again (a node is asked again when it comes back online)",
+			fmt.Errorf("the consumer %s on %s does not exist yet: %w", account.EventConsumerName(), process.EventsStream, err))
+		return
+	}
+	cc, err := process.HearEvents(cons, func(m jetstream.Msg) {
+		if err := m.Ack(); err != nil {
+			logf("acknowledging %s: %v", m.Subject(), err)
+		}
+		node, ours, err := enginereads.NodeOf(m.Subject(), m.Data())
+		switch {
+		case !ours:
+		case err != nil:
+			logf("%s holds what is not %s, and %s is asked again all the same: %v", m.Subject(), enginereads.Event, node, err)
+			reads.AskNode(node, enginereads.Event+" that does not read")
+		default:
+			reads.AskNode(node, enginereads.Event)
+		}
+	}, logf)
+	if err != nil {
+		w.NotHeard(process.EventsStream, enginereads.Event+" is not heard until the assigner starts again", err)
+		return
+	}
+	w.Heard(process.EventsStream)
+	go func() {
+		<-ctx.Done()
+		cc.Stop()
+	}()
+}

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/main_test.go

@@ -1,6 +1,8 @@
 package main
 
 import (
+	"mesh-delivery-assigner/internal/assign"
+
 	"context"
 	"errors"
 	"fmt"
@@ -16,14 +18,20 @@ import (
 
 	"github.com/nats-io/nats.go/jetstream"
 
-	"git.novox.be/novox/mesh-sdk/go/asks"
+	oc "git.novox.be/novox/mesh-contracts/go/seats/operatorchannel"
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/process"
 )
 
 // 1297/B2a: the buckets the program opens are exactly the manifest's reads and states, as the broker names them
 // (`<module>.<state>` read as the bucket `<module>_<state>`), so it is granted what it reads and reads nothing else.
 func TestOpensWhatItsManifestNames(t *testing.T) {
+	// Review round 2: the assigner's views emitter writes its finding view-unsaid (Emitter.Findings set) when it keeps findings.
+	findings := assign.Findings{Put: func(string, []byte) error { return nil }, Delete: func(string) error { return nil }}
+	if viewsEmitter(nil, process.Account{}, nil, findings, nil, t.Logf).Findings == nil {
+		t.Error("the assigner's views emitter writes no view-unsaid finding")
+	}
 	// 1297/B2a: without a credential the program does not start, and says why.
 	if err := run(context.Background(), func(string) string { return "" }, io.Discard); err == nil || !strings.Contains(err.Error(), "MESH_BROKER_FILE") {
 		t.Errorf("run without a credential = %v", err)
@@ -32,14 +40,22 @@ func TestOpensWhatItsManifestNames(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	m, err := catalogue.ParseManifest(raw)
+	m, err := catalogue.Decode(raw)
 	if err != nil {
 		t.Fatal(err)
 	}
 	var reads []string
 	for _, r := range m.Reads {
+		if slices.Contains(readFamilies, r) {
+			continue // a state kept one bucket per node, read by its prefix (ADR 0593 §6), not one bucket
+		}
 		reads = append(reads, strings.Replace(r, ".", "_", 1))
 	}
+	for _, l := range readFamilies {
+		if !slices.Contains(m.Reads, l) {
+			t.Errorf("the program reads the per-node state %s, the manifest does not name it", l)
+		}
+	}
 	var states []string
 	for _, s := range m.State {
 		states = append(states, m.Module+"_"+s.Name)
@@ -47,7 +63,7 @@ func TestOpensWhatItsManifestNames(t *testing.T) {
 	for _, pair := range []struct {
 		what       string
 		code, want []string
-	}{{"reads", readBuckets, reads}, {"states", ownBuckets, states}} {
+	}{{"reads", readBuckets, reads}, {"states", append(slices.Clone(ownBuckets), marksBucket, firstViewsBucket), states}} { // the marks are bound by the views family (views.go)
 		got, want := slices.Sorted(slices.Values(pair.code)), slices.Sorted(slices.Values(pair.want))
 		if !reflect.DeepEqual(got, want) {
 			t.Errorf("the program's %s are %v, the manifest's %v", pair.what, got, want)
@@ -57,7 +73,7 @@ func TestOpensWhatItsManifestNames(t *testing.T) {
 	for _, s := range keptStates {
 		kept = append(kept, m.Module+"_"+s.Name)
 	}
-	if got, want := slices.Sorted(slices.Values(kept)), slices.Sorted(slices.Values(ownBuckets)); !reflect.DeepEqual(got, want) {
+	if got, want := slices.Sorted(slices.Values(kept)), slices.Sorted(slices.Values(append(slices.Clone(ownBuckets), marksBucket, firstViewsBucket))); !reflect.DeepEqual(got, want) {
 		t.Errorf("the program announces %v, keeps %v", got, want)
 	}
 	// ADR 0546: whatever keeps the puts' bucket from opening (not there, not granted, no answer in time), the assigner opens
@@ -66,16 +82,19 @@ func TestOpensWhatItsManifestNames(t *testing.T) {
 		missing string
 		err     error
 		starts  bool
+		said    string
 	}{
-		{delivery.AssignerPutsBucket, jetstream.ErrBucketNotFound, true},
-		{delivery.AssignerPutsBucket, errors.New("nats: permissions violation for subscription to \"$JS.API.STREAM.INFO.KV_mesh-delivery-assigner_puts\""), true},
-		{delivery.AssignerPutsBucket, context.DeadlineExceeded, true},
-		{delivery.AssignerWantsBucket, errors.New("nats: permissions violation"), false},
+		{delivery.AssignerPutsBucket, jetstream.ErrBucketNotFound, true, "no put is taken further"},
+		{delivery.AssignerPutsBucket, errors.New("nats: permissions violation for subscription to \"$JS.API.STREAM.INFO.KV_mesh-delivery-assigner_puts\""), true, "no put is taken further"},
+		{delivery.AssignerPutsBucket, context.DeadlineExceeded, true, "no put is taken further"},
+		{delivery.AssignerWantsBucket, errors.New("nats: permissions violation"), false, ""},
+		// Issue 774: the grants part's grants not there do not stop the start.
+		{delivery.PartGrantsBucket, jetstream.ErrBucketNotFound, true, "no grant is read"},
 	} {
 		var logged string
-		kvs, err := open(context.Background(), refusingJS{missing: c.missing, err: c.err}, func(f string, a ...any) { logged = fmt.Sprintf(f, a...) })
+		kvs, err := open(context.Background(), refusingJS{missing: c.missing, err: c.err}, func(f string, a ...any) { logged += fmt.Sprintf(f, a...) })
 		switch {
-		case c.starts && (err != nil || kvs[c.missing] != nil || len(kvs) != len(readBuckets)+len(ownBuckets)-1 || !strings.Contains(logged, "no put is taken further")):
+		case c.starts && (err != nil || kvs[c.missing] != nil || len(kvs) != len(readBuckets)+len(ownBuckets)-1 || !strings.Contains(logged, c.said)):
 			t.Errorf("%s refused with %v: the start answered %v, %d buckets, logged %q", c.missing, c.err, err, len(kvs), logged)
 		case !c.starts && (err == nil || !strings.Contains(err.Error(), "grant of "+c.missing)): // 1945: named with its grant
 			t.Errorf("%s refused with %v: the start answered %v", c.missing, c.err, err)
@@ -90,15 +109,17 @@ func TestOpensWhatItsManifestNames(t *testing.T) {
 	for _, name := range append(append([]string{}, readBuckets...), ownBuckets...) {
 		kvs[name] = &watchKV{memKV: &memKV{values: map[string][]byte{}}}
 	}
-	ckey, _ := delivery.ComposedNodeKey("ace")
-	cd, err := delivery.EncodeComposedDigest(delivery.ComposedDigest{Digest: "sha256:" + strings.Repeat("d", 64), Judgement: delivery.JudgedUnchanged})
+	placed, err := delivery.PlacementValues(delivery.Placement{Node: "ace"})
 	if err != nil {
 		t.Fatal(err)
 	}
-	kvs[delivery.ControllerComposedBucket].(*watchKV).entries = []kvEntry{{key: ckey, value: cd}}
+	for key, raw := range placed {
+		kv := kvs[delivery.PlacementBucket].(*watchKV)
+		kv.entries = append(kv.entries, kvEntry{key: key, value: raw})
+	}
 	kvs[delivery.AssignerPutsBucket].(*watchKV).closed = true
 	kvs[delivery.AssignerWantsBucket].(*watchKV).wrote = wrote
-	go follow(ctx, nil, nil, kvs, func(asks.Condition) error { return nil }, nil, log.New(io.Discard, "", 0))
+	go follow(ctx, nil, nil, kvs, func(oc.Condition) error { return nil }, assign.Findings{}, nil, nil, log.New(io.Discard, "", 0))
 	select {
 	case key := <-wrote:
 		if key != "want.ace.node" {

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/pass.go

@@ -1,17 +1,21 @@
 package main
 
 import (
+	"bytes"
 	"context"
+	"encoding/json"
 	"errors"
 	"maps"
 	"slices"
 	"strings"
 	"time"
 
-	"git.novox.be/novox/mesh-sdk/go/asks"
+	oc "git.novox.be/novox/mesh-contracts/go/seats/operatorchannel"
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/sdkversion"
+	"git.novox.be/novox/mesh-sdk/go/provisions"
+
+	"git.novox.be/novox/mesh-delivery/sdk/enginereads"
 
 	"mesh-delivery-assigner/internal/assign"
 )
@@ -25,11 +29,18 @@ type passer struct {
 	sdk  string
 	// say publishes a condition to the operator; said is, by condition key and state, what this process has said, so a
 	// pass says a condition once and a restart says it again (the router keeps one per key).
-	say  func(asks.Condition) error
+	say  func(oc.Condition) error
 	said map[string]bool
+	// findings is the assigner's findings bucket (its said conditions, ADR 0564 §2).
+	findings assign.Findings
+	// failedProvisions are the failed provisions whose finding this process wrote (ADR 0570 §4).
+	failedProvisions map[string]bool
+	// missing are the required provisions with no key this process pulsed, and missingSaid those whose finding it wrote.
+	missing, missingSaid map[string]bool
+	// unplaced are the nodes whose unplaced finding this process wrote.
+	unplaced map[string]bool
 	// answeredAt is, by the id of a backup ask, how many values the have had when its answer was written into the want.
 	answeredAt map[string]uint64
-	asks       *composeAsks
 	// now is the clock; nil is time.Now.
 	now func() time.Time
 	// neither is, by node and module, each module on neither list whose condition this process raised (issue 1945). Nil until the
@@ -40,17 +51,59 @@ type passer struct {
 	// noWant is, by node and module, the reason last said why the node gets no want for the module (issue 1945): a reason is
 	// said in the journal when it appears or changes, and its clearing when the node has a want again; one line per change.
 	noWant map[string]string
+	// unreached is, by node and module, the words last said why a wanted module may not be reached there (issue 1960: its
+	// provider is down, which holds no want): said once per words, and once more when it is reached again.
+	unreached map[string]string
 	// nodeFailed is, by node and module, the words of the condition last raised for a failure that is the node's own (ADR 0557
 	// §1, issue 1496): raised once per words, cleared once when it ends.
 	nodeFailed map[string]string
-	// The seat mesh-placement's holder (seat.go, ADR 0567): its calls of the controller (nil: none is made), how it says
+	// callsCleared says the first pass cleared the conditions of refused controller calls a previous process raised
+	// (clearStaleCalls): the assigner makes no such call now (issue 774).
+	callsCleared bool
+	// The seat mesh-placement's holder (seat.go, ADR 0567): its acts (nil: none is made), how it says
 	// the seat's events (nil: none is said), the proposals it said, and what Intended computed by proposal and base.
 	seat         *seatActs
 	publish      publisher
 	saidProposed map[string]bool
+	// convertedAll says every node in the form before was converted to its node and module keys (convertPlacement).
+	convertedAll bool
 	// saidWaits is the last said of the seat's wait for its states (sayWaits).
 	saidWaits string
 	intended  map[string]map[string]map[string]bool
+	// reads keeps what each node's engine states it reads, asked through the node-engine seat's verb (ADR 0618 §3); nil reads
+	// each node's record, as the rules did before the verb. online is, by node, whether the last pass saw it online.
+	reads  *enginereads.Keeper
+	online map[string]bool
+}
+
+// engineReads sets what the rules read of each node's engine (ADR 0618 §3, §4): the statement the verb manifest-reads
+// answered, or its record where the verb was not answered (the fallback) or not asked yet. A node is asked when the
+// assigner first hears of it, and again when it comes back online, since an engine built before the event says none.
+func (p *passer) engineReads(n assign.Nodes) {
+	if p.reads == nil {
+		return
+	}
+	known := p.w.knownNodes()
+	first := p.online == nil
+	for _, node := range known {
+		switch {
+		case first:
+			p.reads.AskNode(node, "the assigner started")
+		case !p.reads.Known(node):
+			p.reads.AskNode(node, "first heard of")
+		case !first && n.Online[node] && !p.online[node]:
+			p.reads.AskNode(node, "back online")
+		}
+	}
+	p.online = maps.Clone(n.Online)
+	if p.online == nil {
+		p.online = map[string]bool{}
+	}
+	for node, reads := range p.reads.Reads(known) {
+		if p.reads.Known(node) {
+			n.Reads[node] = reads
+		}
+	}
 }
 
 func (p *passer) clock() time.Time {
@@ -62,15 +115,13 @@ func (p *passer) clock() time.Time {
 
 func (p *passer) pass(ctx context.Context) {
 	p.placementSeat(ctx)
-	p.compositions(ctx)
 	p.wants(ctx)
 	p.puts(ctx)
 	p.nodeWants(ctx)
 	p.backups(ctx)
 }
 
-// nodeWants writes each node's own want, `want.<node>.node`, naming the digest of the node's own composition, once the
-// controller has composed it and again whenever that digest changes (ADR 0539 §6).
+// nodeWants writes each placed node's own want, `want.<node>.node`: the node composes its own (ADR 0547 §2, ADR 0571 §6).
 func (p *passer) nodeWants(ctx context.Context) {
 	written := p.w.read(delivery.AssignerWantsBucket)
 	placed := p.w.placedNodes()
@@ -86,28 +137,14 @@ func (p *passer) nodeWants(ctx context.Context) {
 		want := delivery.NodeWant{Self: true, Words: "the node composes its own composition (ADR 0547 §2)"}
 		p.put(ctx, delivery.AssignerWantsBucket, key, func() ([]byte, error) { return delivery.EncodeNodeWant(want) })
 	}
-	for node, d := range p.w.nodeComposed() {
-		if placed[node] {
-			continue
-		}
-		key, err := delivery.WantNodeKey(node)
-		if err != nil {
-			continue
-		}
-		if before, err := delivery.DecodeNodeWant(written[key]); err == nil && before.Composed == d.Digest {
-			continue
-		}
-		want := delivery.NodeWant{Composed: d.Digest, Words: "the node's own composition"}
-		p.put(ctx, delivery.AssignerWantsBucket, key, func() ([]byte, error) { return delivery.EncodeNodeWant(want) })
-	}
 }
 
 // wants writes, for every module the trunk holds a fingerprint of, each node's want by the six rules (ADR 0429 §6), and
 // the hold of a fingerprint whose health check failed. The assigner compares its wants with nothing the controller
 // sends: the differences bucket is kept read-only with its history (ADR 0539 §8).
 func (p *passer) wants(ctx context.Context) {
-	get := kvGetter(p.kvs[delivery.ManifestsBucket])
-	assigned, _ := p.w.assigned()
+	get := p.w.getter(delivery.ManifestsBucket) // the indexer's manifests, as its first view and views family say them
+	assigned := p.w.assigned()
 	trunk := p.w.trunk()
 	manifests := map[string]catalogue.Manifest{}
 	for name, mod := range trunk {
@@ -119,6 +156,7 @@ func (p *passer) wants(ctx context.Context) {
 		}
 	}
 	nodes := p.w.nodes(manifests, assigned)
+	p.engineReads(nodes)
 	nodesOf := map[string][]string{}
 	for node, modules := range assigned {
 		for _, m := range modules {
@@ -126,7 +164,13 @@ func (p *passer) wants(ctx context.Context) {
 		}
 	}
 	wanted := p.w.wantsOf()
-	frozen := p.sayPlacement(p.withCalls(p.w.placementDiffers()))
+	chosen, _ := assign.DecodePolicies(p.w.read(assign.PoliciesBucket))
+	provisionsOf := p.provisionsOf()
+	missing := map[string]bool{}
+	defer func() { p.provisionsMissing(ctx, missing) }()
+	defer p.unplacedFindings()
+	defer p.seatHolders(ctx)
+	p.clearStaleCalls()
 	placed := p.w.placedNodes()
 	puts := p.putsByModule()
 	p.staleAsks(ctx, trunk)
@@ -146,22 +190,23 @@ func (p *passer) wants(ctx context.Context) {
 	stale := map[string]neitherOne{}
 	left := map[string]string{}
 	defer func() { p.sayNeither(neither, stale, left) }()
+	// Where grants are read from, once for the pass: the grants part's (issue 774, ADR 0571 clause 9).
+	grants := p.w.grantsBucket()
+	// The verb edges, once for the pass (ADR 0614 §2, §3).
+	moduleGraph := p.moduleGraph()
+	served := p.served(ctx, get, moduleGraph, nodes)
+	offering := p.offering(ctx, get, manifests, nodes) // bus state (ADR 0614 §5)
 	for name := range names {
 		fp := trunk[name].FP2
 		name := name
-		m := assign.Module{Name: name, FP: fp, Manifest: manifests[name], Nodes: nodesOf[name], Now: time.Now(), Puts: puts[name],
+		m := assign.Module{Name: name, FP: fp, Manifest: manifests[name], Needs: trunk[name].Needs, Chosen: chosenOf(chosen, name), Provisions: provisionsOf(name), Answering: answering(manifests, nodes), Offered: offered(manifests), Nodes: nodesOf[name], Now: time.Now(), Puts: puts[name], FormNeeds: p.w.buildNeeds(name, fp),
 			Self: func(node string) bool { return placed[node] },
 			Composed: func(node, fp string) (delivery.ComposedDigest, bool) {
-				if placed[node] {
-					// The node composes its own (ADR 0547 §2, §4): no composition of the controller's is waited for, the want
-					// names the build alone, and the node judges the move itself.
-					return delivery.ComposedDigest{Judgement: delivery.JudgedNeither, Words: "the node composes its own"}, true
-				}
-				return p.w.composed(node, name, fp)
+				return p.w.composed(node, name, fp) // a placed node's own: the digest its own have names (ADR 0571 §6)
 			},
 			GrantedAt: func(fp string) bool {
-				key, err := delivery.ControllerGrantKey(name, fp)
-				return err == nil && p.w.has(delivery.ControllerGrantsBucket, key)
+				key, err := delivery.PartGrantKey(name, fp)
+				return err == nil && p.w.has(grants, key)
 			},
 			Restored: func(node string) bool {
 				key, err := delivery.RestoreAskKey(node, name, fp)
@@ -170,16 +215,17 @@ func (p *passer) wants(ctx context.Context) {
 			Allowed: func(node, digest string) bool {
 				key, err := delivery.RecordAskKey(node, name, digest)
 				return err == nil && p.answeredWith(key, assign.OptionYes)
-			}}
+			},
+			Release: func(fp string) (string, bool) { return p.w.release(name, fp) }}
 		if fp != "" {
 			held, _ := delivery.HeldKey(name, fp)
-			grant, _ := delivery.ControllerGrantKey(name, fp)
+			grant, _ := delivery.PartGrantKey(name, fp)
 			hold, _ := delivery.HoldAskKey(name, fp)
 			m.Released = p.answeredWith(hold, "release")
 			m.Kept = p.answeredWith(hold, "keep")
-			m.Built, m.Held, m.Granted = p.w.built(name, fp), p.w.has(delivery.AssignerWantsBucket, held) && !m.Released, p.w.has(delivery.ControllerGrantsBucket, grant)
-			if raw := p.w.value(delivery.ControllerGrantsBucket, grant); raw != nil {
-				if g, err := delivery.DecodeControllerGrant(raw); err == nil {
+			m.Built, m.Held, m.Granted = p.w.built(name, fp), p.w.has(delivery.AssignerWantsBucket, held) && !m.Released, p.w.has(grants, grant)
+			if raw := p.w.value(grants, grant); raw != nil {
+				if g, err := delivery.DecodeGrant(raw); err == nil {
 					m.GrantedOn = func(node string) bool { return assign.GrantNamesNode(g, node, name) }
 				}
 			}
@@ -187,15 +233,25 @@ func (p *passer) wants(ctx context.Context) {
 				p.clearHeld(name, fp)
 			}
 		}
+		if served != nil {
+			m.Invokes, m.Served = keptInvokes(moduleGraph, name), served
+		}
+		m.Offering = offering
 		last := map[string]string{}
 		for _, node := range m.Nodes {
 			last[node] = p.w.lastHealthy(node, name, fp)
 		}
 		out := assign.Wants(m, nodes, wanted[name], last)
+		for _, node := range m.Nodes {
+			for _, prov := range m.MissingProvisions(node) {
+				missing[node+"."+name+"."+prov] = true
+			}
+		}
 		p.yeses(ctx, name, m, wanted[name], &out)
 		gatherNeither(neither, name, out)
 		leftNeither(left, m, wanted[name], out)
 		p.sayNoWant(name, m.Nodes, wanted[name], out)
+		p.sayUnreached(name, m.Nodes, out)
 		p.sayNodeFailed(name, fp, m.Nodes, nodes, out, first)
 		if first {
 			startClears(stale, m, out)
@@ -224,9 +280,6 @@ func (p *passer) wants(ctx context.Context) {
 			p.recordAsk(ctx, name, fp, need)
 		}
 		for node, want := range out.Wants {
-			if frozen[node+"."+name] {
-				continue // one source alone names it (ADR 0549 §5): no want, and the one written before stays
-			}
 			key, err := delivery.WantKey(node, name)
 			if err != nil {
 				p.logf("no want of %s on %s is written: %v", name, node, err)
@@ -274,6 +327,26 @@ func (p *passer) sayNoWant(module string, nodes []string, before map[string]deli
 	}
 }
 
+// sayUnreached says in the journal, once per words, that a module is wanted on a node and may not be reached there, since
+// no provider of what it requires runs healthy (rule 5, which holds no want: issue 1960), and once when it is reached again.
+func (p *passer) sayUnreached(module string, nodes []string, out assign.Outcome) {
+	if p.unreached == nil {
+		p.unreached = map[string]string{}
+	}
+	for _, node := range nodes {
+		key := node + "." + module
+		why, last := out.Unreached[node], p.unreached[key]
+		switch {
+		case why != "" && why != last:
+			p.logf("%s on %s is wanted and may not be reached: %s", module, node, why)
+			p.unreached[key] = why
+		case why == "" && last != "":
+			p.logf("%s on %s is reached: its providers run healthy", module, node)
+			delete(p.unreached, key)
+		}
+	}
+}
+
 // sayNodeFailed raises, once per node and words, the condition of a failed health check of a module's newest fingerprint fp
 // that is the node's own, since fp runs healthy elsewhere and is not held (ADR 0557 §1, issue 1496), and says it in the journal;
 // it clears the condition once when the node no longer fails alone, or is no longer one of the module's nodes. The first pass
@@ -448,57 +521,6 @@ func (p *passer) sayNeither(now, stale map[string]neitherOne, left map[string]st
 	}
 }
 
-// compositions writes the composition check's verdict of every group the indexer holds a candidate for, under the
-// checker's key of that check: waits, with why, while the indexer holds what it composes from only in part.
-func (p *passer) compositions(ctx context.Context) {
-	if p.sdk == "" {
-		p.sdk = sdkversion.Version()
-	}
-	written := p.w.read(delivery.AssignerCompositionsBucket)
-	trunk := p.w.trunk()
-	var mesh *assign.Mesh
-	seen := map[string]bool{}
-	if p.asks != nil {
-		defer p.asks.sweep(seen)
-	}
-	for key, value := range p.w.read(delivery.CandidatesBucket) {
-		c, err := delivery.DecodeCandidate(value)
-		if err != nil {
-			p.logf("the candidate %s cannot be read, so it is not composed: %v", key, err)
-			continue
-		}
-		out, err := delivery.CompositionKey(c.Group, c.HeadsHash)
-		if err != nil {
-			p.logf("the candidate %s names no composition key: %v", key, err)
-			continue
-		}
-		began := time.Now()
-		ch, waits := p.w.change(ctx, kvGetter(p.kvs[delivery.ManifestsBucket]), c, trunk)
-		var v delivery.CompositionVerdict
-		if waits != "" {
-			v = delivery.CompositionVerdict{Group: c.Group, Heads: c.HeadsHash, State: delivery.CompositionWaits, Words: waits}
-		} else {
-			if mesh == nil {
-				m := p.w.mesh(ctx, kvGetter(p.kvs[delivery.ManifestsBucket]))
-				mesh = &m
-			}
-			if ch.SDKHead != "" && p.asks != nil {
-				// A group with a mesh-sdk member is composed by the composer built at its head (ADR 0482 clauses 3 to 5).
-				v = p.composeAtHead(ctx, *mesh, ch, seen, began)
-			} else {
-				v = assign.Compose(*mesh, ch, p.sdk, time.Since(began))
-			}
-		}
-		if before, err := delivery.DecodeCompositionVerdict(written[out]); err == nil {
-			before.Took, before.V = v.Took, 0
-			if delivery.SameCompositionVerdict(before, v) {
-				continue
-			}
-		}
-		p.put(ctx, delivery.AssignerCompositionsBucket, out, func() ([]byte, error) { return delivery.EncodeCompositionVerdict(v) })
-	}
-}
-
 // put writes one key of the assigner's own bucket; a write that fails is said and made again at the next pass.
 func (p *passer) put(ctx context.Context, bucket, key string, encode func() ([]byte, error)) {
 	value, err := encode()
@@ -506,6 +528,11 @@ func (p *passer) put(ctx context.Context, bucket, key string, encode func() ([]b
 		p.logf("%s %s is not written: %v", bucket, key, err)
 		return
 	}
+	// A value the bucket already holds is not put again: every put is a change its watchers hear, and a want put unchanged
+	// made its node compose again (issue 774, 2026-10-31: novox composed every 8 s, two asks of the vault each time).
+	if held := p.w.value(bucket, key); held != nil && bytes.Equal(held, value) {
+		return
+	}
 	if _, err := p.kvs[bucket].Put(ctx, key, value); err != nil && !errors.Is(err, context.Canceled) {
 		p.logf("%s %s could not be written: %v", bucket, key, err)
 		return
@@ -527,7 +554,7 @@ func (p *passer) holdAsk(ctx context.Context, module, fp string, fresh *delivery
 	asking := int(now.Unix())
 	h := p.heldHold(module, fp, fresh)
 	a := assign.HoldAsk(key, module, fp, h.Node, h.Words, asking, now)
-	p.put(ctx, delivery.AssignerAsksBucket, key, func() ([]byte, error) { return delivery.EncodeAssignerAsk(key, a) })
+	p.put(ctx, delivery.AssignerAsksBucket, key, func() ([]byte, error) { return assign.EncodeAsk(key, a) })
 }
 
 // lift takes away a hold the assigner lifted by itself, since every node that runs the module runs the held fingerprint healthy
@@ -585,6 +612,14 @@ func (p *passer) staleAsk(key string, trunk map[string]delivery.Module) bool {
 		if !on {
 			return true
 		}
+		// A node that composes its own asks about its own composition, which its have names as the one it waits on (yeses): that
+		// ask stands while the have waits on it, whatever the controller composes (issue 774, 2026-10-31: novox's asks of
+		// postgres, keycloak and mongodb were taken away and made again under a new id every pass, so no answer could count).
+		if hkey, err := delivery.HaveKey(k.Node, k.Module); err == nil {
+			if h, err := delivery.DecodeHave(p.w.value(delivery.HaveBucket, hkey)); err == nil && h.Phase == delivery.PhaseWaitingYes && h.Waits == k.Composed {
+				return false
+			}
+		}
 		// The assigner asks about a composition at more than the trunk fingerprint: a node held back by the rules is asked about the
 		// revised composition of the fingerprint it runs (ADR 0545), and a node's first want at the older fingerprint it runs. So a
 		// record ask is stale only when its digest is the composition of none of the fingerprints the node can still want (the
@@ -702,7 +737,7 @@ func (p *passer) restoreAsk(ctx context.Context, module, node, fp string) {
 	}
 	words := p.heldHold(module, fp, nil).Words
 	a := assign.RestoreAsk(key, node, module, fp, words, time.Now())
-	p.put(ctx, delivery.AssignerAsksBucket, key, func() ([]byte, error) { return delivery.EncodeAssignerAsk(key, a) })
+	p.put(ctx, delivery.AssignerAsksBucket, key, func() ([]byte, error) { return assign.EncodeAsk(key, a) })
 }
 
 // answeredWith says whether the teller wrote an answer to the ask at key as it stands now and the option chosen is option. The
@@ -714,12 +749,12 @@ func (p *passer) answeredWith(key, option string) bool {
 	if !ok || a.Option != option {
 		return false
 	}
-	ask, err := delivery.DecodeAssignerAsk(key, p.w.value(delivery.AssignerAsksBucket, key))
+	_, ask, err := assign.DecodeAsk(key, p.w.value(delivery.AssignerAsksBucket, key))
 	if err != nil {
 		return false
 	}
 	id, _, _ := strings.Cut(a.Warrant, "@")
-	return id == ask.Ask.ID
+	return id == ask.ID
 }
 
 // clearHeld clears, once, the condition of a hold the operator released.
@@ -744,7 +779,7 @@ func (p *passer) recordAsk(ctx context.Context, module, fp string, need assign.R
 		return
 	}
 	a := assign.RecordAsk(key, need.Node, module, fp, need, time.Now())
-	p.put(ctx, delivery.AssignerAsksBucket, key, func() ([]byte, error) { return delivery.EncodeAssignerAsk(key, a) })
+	p.put(ctx, delivery.AssignerAsksBucket, key, func() ([]byte, error) { return assign.EncodeAsk(key, a) })
 }
 
 // backups sees to the modules held on a node because the backup before an apply failed (the have's phase held, ADR 0539 §16):
@@ -775,7 +810,7 @@ func (p *passer) backups(ctx context.Context) {
 		if err != nil {
 			continue
 		}
-		current, there := delivery.DecodeAssignerAsk(akey, p.w.read(delivery.AssignerAsksBucket)[akey])
+		current, currentAsk, there := assign.DecodeAsk(akey, p.w.read(delivery.AssignerAsksBucket)[akey])
 		if there != nil || assign.BackupAskDigest(current) != want.Composed {
 			after := -1
 			if there == nil {
@@ -785,7 +820,7 @@ func (p *passer) backups(ctx context.Context) {
 			continue
 		}
 		answer, answered := p.w.answer(akey)
-		if router, _, _ := strings.Cut(answer.Warrant, "@"); !answered || router != current.Ask.ID ||
+		if router, _, _ := strings.Cut(answer.Warrant, "@"); !answered || router != currentAsk.ID ||
 			(answer.Option != delivery.BackupAgain && answer.Option != delivery.BackupSkip) {
 			continue // not answered yet: the ask stands
 		}
@@ -796,7 +831,7 @@ func (p *passer) backups(ctx context.Context) {
 			if wkey, err := delivery.WantKey(node, module); err == nil {
 				w := want
 				p.put(ctx, delivery.AssignerWantsBucket, wkey, func() ([]byte, error) { return delivery.EncodeWant(w) })
-				p.answeredAt[current.Ask.ID] = haveChanges
+				p.answeredAt[currentAsk.ID] = haveChanges
 			}
 			continue
 		}
@@ -804,8 +839,8 @@ func (p *passer) backups(ctx context.Context) {
 			continue
 		}
 		// The answer is in the want. The node retried and the backup failed again when the have took another value since.
-		if seen, known := p.answeredAt[current.Ask.ID]; !known {
-			p.answeredAt[current.Ask.ID] = haveChanges // after a restart: wait for the next failure
+		if seen, known := p.answeredAt[currentAsk.ID]; !known {
+			p.answeredAt[currentAsk.ID] = haveChanges // after a restart: wait for the next failure
 		} else if haveChanges > seen {
 			p.backupAsk(ctx, akey, node, module, want, have.Detail, assign.NextBackupAsking(current.Asking))
 		}
@@ -815,7 +850,7 @@ func (p *passer) backups(ctx context.Context) {
 // backupAsk writes the backup ask at its asking and raises the condition of the failed backup, once.
 func (p *passer) backupAsk(ctx context.Context, key, node, module string, want delivery.Want, words string, asking int) {
 	a := assign.BackupAsk(key, node, module, want.FP, want.Composed, words, asking, time.Now())
-	p.put(ctx, delivery.AssignerAsksBucket, key, func() ([]byte, error) { return delivery.EncodeAssignerAsk(key, a) })
+	p.put(ctx, delivery.AssignerAsksBucket, key, func() ([]byte, error) { return assign.EncodeAsk(key, a) })
 	c := assign.BackupCondition(node, module, want.FP, words, true)
 	if p.say == nil || p.said[c.Key] {
 		return
@@ -827,46 +862,12 @@ func (p *passer) backupAsk(ctx context.Context, key, node, module string, want d
 	p.said[c.Key] = true
 }
 
-// sayPlacement raises, once, the condition of every pair the controller's assignments and the catalogue's placement do not
-// both name, clears it once they agree, and answers those pairs by node and module (ADR 0549 §5): the pass writes no want
-// for them and keeps the one written before. A say that fails is made again at the next pass.
-func (p *passer) sayPlacement(differ []assign.Pair) map[string]bool {
-	frozen := map[string]bool{}
-	now := map[string]bool{}
-	for _, d := range differ {
-		frozen[d.Node+"."+d.Module] = true
-		c := assign.PlacementCondition(d, true)
-		now[c.Key] = true
-		if p.said[c.Key+".raised"] {
-			continue
-		}
-		p.logf("%s on %s is named by %s alone: no want is written for it there until both sources name it (ADR 0549 §5)", d.Module, d.Node, d.Only)
-		if err := p.say(c); err != nil {
-			p.logf("the placement condition of %s on %s could not be said, and is said at the next pass: %v", d.Module, d.Node, err)
-			continue
-		}
-		p.said[c.Key+".raised"] = true
-	}
-	prefix := delivery.AssignerModule + ".placement."
-	for key := range p.said {
-		c, raised := strings.CutSuffix(key, ".raised")
-		if !raised || !strings.HasPrefix(c, prefix) || now[c] {
-			continue
-		}
-		node, module, _ := strings.Cut(strings.TrimPrefix(c, prefix), ".")
-		if err := p.say(assign.PlacementCondition(assign.Pair{Node: node, Module: module}, false)); err != nil {
-			p.logf("the placement condition of %s on %s could not be cleared, and is cleared at the next pass: %v", module, node, err)
-			continue
-		}
-		delete(p.said, key)
-	}
-	return frozen
-}
-
 // yeses writes a placed node's wants naming the build alone, and sees to the moves a node that composes its own judged a
 // person must allow (ADR 0547 §3): for a have of phase
 // waiting-yes it raises the record ask once, naming the composition waiting and the node's judgement, and on a yes writes
-// the want again naming it; a yes once written is kept while the want stays at its build, so the node is not asked again.
+// the want again naming it; a yes once written is kept while the want stays at its build, so the node is not asked again. A
+// move of the build alone (the have says so) to a build an approved release carries is given its yes by that Approve, the
+// want naming the release, with no ask (ADR 0601 §1).
 func (p *passer) yeses(ctx context.Context, module string, m assign.Module, before map[string]delivery.Want, out *assign.Outcome) {
 	for _, node := range m.Nodes {
 		if m.Self == nil || !m.Self(node) {
@@ -883,26 +884,283 @@ func (p *passer) yeses(ctx context.Context, module string, m assign.Module, befo
 		if w.Removed {
 			continue
 		}
-		yes := ""
+		yes, release := "", ""
 		if had && was.FP == w.FP {
-			yes = was.Yes
+			yes, release = was.Yes, was.Release
 		}
 		key, err := delivery.HaveKey(node, module)
 		if err != nil {
 			continue
 		}
 		if h, err := delivery.DecodeHave(p.w.value(delivery.HaveBucket, key)); err == nil && h.Phase == delivery.PhaseWaitingYes && h.Waits != yes {
-			if m.Allowed != nil && m.Allowed(node, h.Waits) {
-				yes = h.Waits
-			} else {
+			switch {
+			case m.Allowed != nil && m.Allowed(node, h.Waits):
+				yes, release = h.Waits, ""
+			case h.BuildAlone && h.FP != w.FP && m.Release != nil:
+				// A move of the build alone, to the build an approved release carries: that Approve is the yes (ADR 0601 §1),
+				// named in the want. A move that changes a setting or a secret too, or one the node could not tell, is asked.
+				if r, ok := m.Release(w.FP); ok {
+					yes, release = h.Waits, r
+					break
+				}
+				p.recordAsk(ctx, module, w.FP, assign.RecordNeed{Node: node, Digest: h.Waits, Judgement: h.Judgement, Words: h.Detail})
+			default:
 				p.recordAsk(ctx, module, w.FP, assign.RecordNeed{Node: node, Digest: h.Waits, Judgement: h.Judgement, Words: h.Detail})
 			}
 		}
 		// A want carried over from before the node composed its own may still name the controller's composition; a placed
 		// node's want names the build alone (ADR 0547 §2).
-		if yes != w.Yes || w.Composed != "" || !w.Self {
-			w.Yes, w.Composed, w.Self = yes, "", true
+		if yes == "" {
+			release = ""
+		}
+		if yes != w.Yes || release != w.Release || w.Composed != "" || !w.Self {
+			w.Yes, w.Release, w.Composed, w.Self = yes, release, "", true
 			out.Wants[node] = w
 		}
 	}
 }
+
+// chosenOf is a person's choice for module, nil when none.
+func chosenOf(chosen map[string]catalogue.PersonPolicy, module string) *catalogue.PersonPolicy {
+	if c, ok := chosen[module]; ok {
+		return &c
+	}
+	return nil
+}
+
+// provisionsOf answers, per module, the provisions it consumes on a node, by key (ADR 0570 §4), from the seat
+// mesh-provisioner's state; nil while the state is not read (the seat not delivered yet), so no want waits on it. A failed
+// provision is also said as the assigner's finding `provider.<key>.provision-failed` (a waiting one is the watchman's
+// needs-operator), deleted once it is no longer failed.
+func (p *passer) provisionsOf() func(module string) func(node string) map[string]provisions.Provision {
+	if p.kvs[provisions.ProvisionsBucket] == nil {
+		return func(string) func(string) map[string]provisions.Provision { return nil }
+	}
+	by := map[string]map[string]map[string]provisions.Provision{} // module, node, key
+	failed := map[string]provisions.Provision{}
+	for key, raw := range p.w.read(provisions.ProvisionsBucket) {
+		pr, err := provisions.Decode(raw)
+		if err != nil {
+			continue
+		}
+		node, module := pr.Consumer.Node, pr.Consumer.Module
+		if by[module] == nil {
+			by[module] = map[string]map[string]provisions.Provision{}
+		}
+		if by[module][node] == nil {
+			by[module][node] = map[string]provisions.Provision{}
+		}
+		by[module][node][key] = pr
+		if pr.State == provisions.Failed {
+			failed[key] = pr
+		}
+	}
+	p.provisionFindings(failed)
+	return func(module string) func(string) map[string]provisions.Provision {
+		return func(node string) map[string]provisions.Provision { return by[module][node] }
+	}
+}
+
+// provisionFindings writes the finding of each failed provision and deletes the ones no longer failed.
+func (p *passer) provisionFindings(failed map[string]provisions.Provision) {
+	if p.findings.Put == nil {
+		return
+	}
+	now := time.Now
+	if p.now != nil {
+		now = p.now
+	}
+	for key, pr := range failed {
+		if p.failedProvisions[key] {
+			continue
+		}
+		value, err := assign.ProvisionFailedFinding(key, pr, now())
+		if err == nil {
+			err = p.findings.Put(assign.ProvisionFailedKey(key), value)
+		}
+		if err != nil {
+			p.logf("the failed provision %s is not said: %v", key, err)
+			continue
+		}
+		if p.failedProvisions == nil {
+			p.failedProvisions = map[string]bool{}
+		}
+		p.failedProvisions[key] = true
+	}
+	for key := range p.failedProvisions {
+		if _, still := failed[key]; still {
+			continue
+		}
+		if err := p.findings.Delete(assign.ProvisionFailedKey(key)); err != nil {
+			p.logf("the failed provision %s is not cleared: %v", key, err)
+			continue
+		}
+		delete(p.failedProvisions, key)
+	}
+}
+
+// MissingBound is how long a required provision may have no key before it is said: a module's delivery bound, the default
+// when its manifest names none (ADR 0564 clause 13 (d)).
+var MissingBound = delivery.DefaultDeliveryBound
+
+// missingPulse is the pulse key of a provision with no key, `provision-missing.<node>.<module>.<provision>`.
+func missingPulse(key string) string { return "provision-missing." + key }
+
+// provisionsMissing is the loud end of a required provision with no key (the lead, 2026-10-29, ADR 0570 §4): each one is
+// pulsed with the bound when it is first seen; once its pulse expired and it still has no key, the finding
+// `provider.<node>.<module>.<provision>.provision-missing` is written; one keyed again ends both. The pulse's expiry, heard on
+// the watch, is the pass that writes it: no timer.
+func (p *passer) provisionsMissing(ctx context.Context, missing map[string]bool) {
+	pulses := p.kvs[delivery.PlacementPulsesBucket]
+	if p.missing == nil {
+		p.missing = map[string]bool{}
+	}
+	for key := range missing {
+		switch {
+		case !p.missing[key]:
+			p.missing[key] = true
+			if pulses != nil {
+				p.pulse(ctx, missingPulse(key), MissingBound)
+			}
+		case pulses == nil || !p.pulsing(missingPulse(key)):
+			if p.missingSaid[key] || p.findings.Put == nil {
+				continue
+			}
+			value, err := assign.ProvisionMissingFinding(key, MissingBound, p.clock())
+			if err == nil {
+				err = p.findings.Put(assign.ProvisionMissingKey(key), value)
+			}
+			if err != nil {
+				p.logf("the missing provision %s is not said: %v", key, err)
+				continue
+			}
+			if p.missingSaid == nil {
+				p.missingSaid = map[string]bool{}
+			}
+			p.missingSaid[key] = true
+		}
+	}
+	for key := range p.missing {
+		if missing[key] {
+			continue
+		}
+		delete(p.missing, key)
+		if pulses != nil && p.pulsing(missingPulse(key)) {
+			if err := pulses.Delete(ctx, missingPulse(key)); err == nil {
+				p.w.put(delivery.PlacementPulsesBucket, missingPulse(key), nil)
+			}
+		}
+		if p.missingSaid[key] && p.findings.Delete != nil {
+			if err := p.findings.Delete(assign.ProvisionMissingKey(key)); err != nil {
+				p.logf("the missing provision %s is not cleared: %v", key, err)
+				p.missing[key] = true
+				continue
+			}
+			delete(p.missingSaid, key)
+		}
+	}
+}
+
+// unplacedFindings writes, from the lease write, the finding `machine.<node>.unplaced` for each node that runs but no
+// placement names, which gets no want (ADR 0571 §6), and deletes it once the node is placed.
+func (p *passer) unplacedFindings() {
+	if p.findings.Put == nil {
+		return
+	}
+	now := []string(p.w.unplacedNodes())
+	is := map[string]bool{}
+	for _, node := range now {
+		is[node] = true
+		if p.unplaced[node] {
+			continue
+		}
+		value, err := assign.UnplacedFinding(node, p.clock())
+		if err == nil {
+			err = p.findings.Put(assign.UnplacedKey(node), value)
+		}
+		if err != nil {
+			p.logf("the unplaced node %s is not said: %v", node, err)
+			continue
+		}
+		if p.unplaced == nil {
+			p.unplaced = map[string]bool{}
+		}
+		p.unplaced[node] = true
+	}
+	for node := range p.unplaced {
+		if is[node] {
+			continue
+		}
+		if err := p.findings.Delete(assign.UnplacedKey(node)); err == nil {
+			delete(p.unplaced, node)
+		}
+	}
+}
+
+// seatHolders writes the seat mesh-placement's state seat-holders from every node's placement (ADR 0571 §4): one key per
+// seat held once, `<seat>`, and one per node of a node seat, `<seat>.<node>`, written only where it differs, and a key no
+// placement holds any more deleted. A pass follows each placement change and each manifest the indexer takes in, so no
+// timer writes it.
+func (p *passer) seatHolders(ctx context.Context) {
+	kv := p.kvs[delivery.SeatHoldersBucket]
+	if kv == nil {
+		return
+	}
+	placements := p.w.placements()
+	if len(placements) == 0 {
+		return // no placement read yet: nothing is known of who holds what, and nothing is deleted
+	}
+	want := delivery.SeatHoldersOf(placements)
+	have := p.w.read(delivery.SeatHoldersBucket)
+	for key, sh := range want {
+		value, err := json.Marshal(sh)
+		if err != nil || string(have[key]) == string(value) {
+			continue
+		}
+		p.put(ctx, delivery.SeatHoldersBucket, key, func() ([]byte, error) { return value, nil })
+	}
+	for key := range have {
+		if _, ok := want[key]; ok {
+			continue
+		}
+		if err := kv.Delete(ctx, key); err != nil {
+			p.logf("the seat holders %s are not deleted: %v", key, err)
+			continue
+		}
+		p.w.put(delivery.SeatHoldersBucket, key, nil)
+	}
+}
+
+// offered says whether some manifest of the trunk, or a module the mesh provides itself, offers a provision under its name
+// (a module offers its own name too, catalogue.Manifest.Offers): what a requirement nobody offers is told from.
+func offered(manifests map[string]catalogue.Manifest) func(string) bool {
+	names := map[string]bool{}
+	add := func(m catalogue.Manifest) {
+		for _, o := range m.Offers() {
+			names[o] = true
+		}
+	}
+	for _, m := range manifests {
+		add(m)
+	}
+	for _, module := range delivery.ProvidedModules() {
+		if m, _, err := delivery.ProvidedManifest(module); err == nil {
+			add(m)
+		}
+	}
+	return func(provision string) bool { return names[provision] }
+}
+
+// answering is, by provision, the manifests of the modules placed on some node that provide it: what a want's
+// provisions are judged by (catalogue.Awaited, issue 774). A provider in the catalogue placed nowhere answers nobody.
+func answering(manifests map[string]catalogue.Manifest, n assign.Nodes) func(string) []catalogue.Manifest {
+	return func(provision string) []catalogue.Manifest {
+		var out []catalogue.Manifest
+		for _, name := range slices.Sorted(maps.Keys(n.Providers[provision])) {
+			if m, ok := manifests[name]; ok && len(n.Providers[provision][name]) > 0 {
+				out = append(out, m)
+			}
+		}
+		return out
+	}
+}

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/pass_test.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"bytes"
 	"context"
 	"encoding/json"
 	"errors"
@@ -12,10 +13,15 @@ import (
 
 	"github.com/nats-io/nats.go/jetstream"
 
-	"git.novox.be/novox/mesh-sdk/go/asks"
+	occ "git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient"
+	oc "git.novox.be/novox/mesh-contracts/go/seats/operatorchannel"
+	"git.novox.be/novox/mesh-sdk/go/busretry"
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/provider"
+
+	"git.novox.be/novox/mesh-contracts/go/seats/nodeengine"
+	"git.novox.be/novox/mesh-delivery/sdk/enginereads"
+	"git.novox.be/novox/mesh-delivery/sdk/graph"
 
 	"mesh-delivery-assigner/internal/assign"
 )
@@ -24,9 +30,16 @@ import (
 type memKV struct {
 	jetstream.KeyValue
 	values map[string][]byte
+	puts   int // how many puts reached the bucket
 }
 
 func (m *memKV) Put(_ context.Context, key string, value []byte) (uint64, error) {
+	m.values[key] = value
+	m.puts++
+	return uint64(len(m.values)), nil
+}
+
+func (m *memKV) Create(_ context.Context, key string, value []byte, _ ...jetstream.KVCreateOpt) (uint64, error) {
 	m.values[key] = value
 	return uint64(len(m.values)), nil
 }
@@ -42,6 +55,34 @@ func newPasser(kvs buckets, at time.Time) *passer {
 		now: func() time.Time { return at }}
 }
 
+// placeOn puts the seat's placement of node, naming the modules, into the world: one node key and a key per module
+// (research 072 row 37).
+func placeOn(t *testing.T, w *world, node string, modules ...string) {
+	t.Helper()
+	pl := delivery.Placement{Node: node}
+	for _, m := range modules {
+		pl.Modules = append(pl.Modules, delivery.PlacedModule{Module: m})
+	}
+	values, err := delivery.PlacementValues(pl)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for key, raw := range values {
+		w.put(delivery.PlacementBucket, key, raw)
+	}
+}
+
+// composes puts the digest the node's own have names as its composition (`<node>.node` of the haves).
+func composes(t *testing.T, w *world, node, digest string) {
+	t.Helper()
+	raw, err := delivery.EncodeHaveNode(delivery.HaveNode{Composed: digest})
+	if err != nil {
+		t.Fatal(err)
+	}
+	key, _ := delivery.HaveNodeKey(node)
+	w.put(delivery.HaveBucket, key, raw)
+}
+
 var fpTest = delivery.SourcePrefix2 + strings.Repeat("b", 64)
 
 // 1906/H2: given a hold lifted by itself, when the assigner is started again and the same fingerprint is held again, then the
@@ -54,7 +95,7 @@ func TestAHoldAskedAgainAfterALiftAndARestartHasANewID(t *testing.T) {
 	held := &delivery.Held{Node: "ace", Words: "health failed"}
 	first := newPasser(kvs, time.Date(2026, 10, 25, 1, 0, 0, 0, time.UTC))
 	first.holdAsk(context.Background(), "web", fpTest, held)
-	a1, err := delivery.DecodeAssignerAsk(key, asksKV.values[key])
+	a1, err := decodeAsk(key, asksKV.values[key])
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -64,7 +105,7 @@ func TestAHoldAskedAgainAfterALiftAndARestartHasANewID(t *testing.T) {
 	}
 	again := newPasser(kvs, time.Date(2026, 10, 25, 2, 0, 0, 0, time.UTC)) // started again: it remembers nothing
 	again.holdAsk(context.Background(), "web", fpTest, held)
-	a2, err := delivery.DecodeAssignerAsk(key, asksKV.values[key])
+	a2, err := decodeAsk(key, asksKV.values[key])
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -76,16 +117,24 @@ func TestAHoldAskedAgainAfterALiftAndARestartHasANewID(t *testing.T) {
 // 1906/H4: an answer counts only for the asking it answered: an answer to an earlier hold of the same fingerprint, or to an ask
 // taken away, is not taken for the hold that stands now.
 func TestAnAnswerCountsOnlyForTheAskingItAnswered(t *testing.T) {
+	// ADR 0603 §5: a provision is offered by a manifest's provides, by a module's own name, and by a module the mesh provides
+	// itself (mesh-addressing, mesh-wireguard's); nothing else.
+	off := offered(map[string]catalogue.Manifest{"node-tools": {Module: "node-tools"}, "db": {Module: "db", Provides: []catalogue.Offer{{Name: "database"}}}})
+	for provision, want := range map[string]bool{"node-tools": true, "database": true, "mesh-addressing": true, "queue": false} {
+		if off(provision) != want {
+			t.Errorf("offered(%s) = %v, want %v", provision, !want, want)
+		}
+	}
 	key, _ := delivery.HoldAskKey("web", fpTest)
 	p := newPasser(buckets{}, time.Now())
 	put := func(asking int) string {
 		a := assign.HoldAsk(key, "web", fpTest, "ace", "health failed", asking, time.Now())
-		v, err := delivery.EncodeAssignerAsk(key, a)
+		v, err := assign.EncodeAsk(key, a)
 		if err != nil {
 			t.Fatal(err)
 		}
 		p.w.put(delivery.AssignerAsksBucket, key, v)
-		return a.Ask.ID
+		return mustAskID(a)
 	}
 	first := put(100)
 	v, _ := delivery.EncodeAnswer(delivery.Answer{Option: "release", Warrant: first + "@2026-10-25T01:00:00Z", Words: "the operator"})
@@ -105,6 +154,89 @@ func TestAnAnswerCountsOnlyForTheAskingItAnswered(t *testing.T) {
 		t.Error("an answer to an ask taken away was taken")
 	}
 	t.Run("a put of the bus acts on the operator's warrant alone", putOfTheBus)
+	// ADR 0614 §4: the rules read what each node's engine states it reads from its record in `<node>.node`; a node with no
+	// record, or one that states nothing, is read as stating nothing (the rules then read the baseline).
+	t.Run("the rules read what each node's engine reads", func(t *testing.T) {
+		w := newWorld()
+		for node, reads := range map[string][]string{"ace": {"word:module", "word:tool-runner"}, "g14": nil} {
+			raw, err := delivery.EncodeHaveNode(delivery.HaveNode{Record: &delivery.NodeRecord{Node: node, ManifestReads: reads}})
+			if err != nil {
+				t.Fatal(err)
+			}
+			key, _ := delivery.HaveNodeKey(node)
+			w.put(delivery.HaveBucket, key, raw)
+		}
+		n := w.nodes(nil, nil)
+		if !slices.Equal(n.Reads["ace"], []string{"word:module", "word:tool-runner"}) || len(n.Reads["g14"]) != 0 || len(n.Reads["novox"]) != 0 {
+			t.Errorf("the nodes' reads are %v", n.Reads)
+		}
+		// ADR 0618 §3: with the verb asked, a node's reads are what its engine answered; where the engine answers it does not
+		// serve the verb, its record is read once in its place (the fallback, issue 774); a node asked again when it comes
+		// back online, since an engine built before the event says none.
+		asked := map[string]int{}
+		call := func(node, key string, _ any) (json.RawMessage, error) {
+			asked[node]++
+			if node == "g14" || key != enginereads.Invoke {
+				return nil, &busretry.Answered{Words: "the seat node-engine serves no verb manifest-reads"}
+			}
+			return json.Marshal(nodeengine.ManifestReadsAnswer{V: 1, Node: node, ManifestReads: []string{"form:new"}, StatedAt: time.Now().Format(time.RFC3339Nano)})
+		}
+		p := &passer{w: w, reads: &enginereads.Keeper{Call: call, Fallback: w.recordReads, Sync: true}}
+		on, _ := delivery.EncodePresence(delivery.Presence{Online: false})
+		w.put(delivery.PresenceBucket, "ace", on)
+		n = w.nodes(nil, nil)
+		p.engineReads(n)
+		if !slices.Equal(n.Reads["ace"], []string{"form:new"}) || len(n.Reads["g14"]) != 0 || asked["ace"] != 1 {
+			t.Errorf("with the verb the nodes' reads are %v (asked %v)", n.Reads, asked)
+		}
+		if s := p.reads.Statements(); s["ace"].From != enginereads.FromVerb || s["g14"].From != enginereads.FromRecord {
+			t.Errorf("the statements are %+v", s)
+		}
+		p.engineReads(w.nodes(nil, nil))
+		on, _ = delivery.EncodePresence(delivery.Presence{Online: true})
+		w.put(delivery.PresenceBucket, "ace", on)
+		p.engineReads(w.nodes(nil, nil))
+		if asked["ace"] != 2 {
+			t.Errorf("ace, back online, was asked %d times, want 2", asked["ace"])
+		}
+		// The contract carries no checks, so its reader judges what the engine says (mesh-contracts seats/nodeengine): an
+		// answer or an event that does not hold is no statement, and an event's node is its subject's last token.
+		now := time.Now().Format(time.RFC3339Nano)
+		for _, row := range []struct {
+			name  string
+			raw   string
+			stays bool
+		}{
+			{"a whole answer", `{"v":1,"node":"ace","manifest-reads":["form:new"],"stated-at":"` + now + `"}`, true},
+			{"an engine stating nothing", `{"v":1,"node":"ace","stated-at":"` + now + `"}`, true},
+			{"another layout", `{"v":2,"node":"ace","stated-at":"` + now + `"}`, false},
+			{"no node", `{"v":1,"node":"","stated-at":"` + now + `"}`, false},
+			{"a node that is no token", `{"v":1,"node":"a.ce","stated-at":"` + now + `"}`, false},
+			{"another node's answer", `{"v":1,"node":"g14","stated-at":"` + now + `"}`, false},
+			{"an empty capability", `{"v":1,"node":"ace","manifest-reads":[""],"stated-at":"` + now + `"}`, false},
+			{"a time that is no time", `{"v":1,"node":"ace","stated-at":"yesterday"}`, false},
+		} {
+			s := enginereads.Ask(func(string, string, any) (json.RawMessage, error) { return json.RawMessage(row.raw), nil }, "ace", time.Now())
+			if (s.From == enginereads.FromVerb) != row.stays || !s.Answered {
+				t.Errorf("answer %s: %+v", row.name, s)
+			}
+		}
+		for _, row := range []struct {
+			name, subject, raw string
+			ours, fails        bool
+		}{
+			{"the event", enginereads.SubjectPrefix + "ace", `{"v":1,"node":"ace","at":"` + now + `","why":"returned"}`, true, false},
+			{"another reason", enginereads.SubjectPrefix + "ace", `{"v":1,"node":"ace","at":"` + now + `","why":"bored"}`, true, true},
+			{"another node in the body", enginereads.SubjectPrefix + "ace", `{"v":1,"node":"g14","at":"` + now + `","why":"started"}`, true, true},
+			{"a time that is no time", enginereads.SubjectPrefix + "ace", `{"v":1,"node":"ace","at":"x","why":"started"}`, true, true},
+			{"another event", "mesh.seat.node-engine.event.done.ace", `{}`, false, false},
+		} {
+			_, ours, err := enginereads.NodeOf(row.subject, []byte(row.raw))
+			if ours != row.ours || (err != nil) != row.fails {
+				t.Errorf("event %s: ours %v, %v", row.name, ours, err)
+			}
+		}
+	})
 }
 
 // memEntry is a value a memKV holds, as a bucket's Get answers it.
@@ -135,6 +267,9 @@ func (m *memKV) Update(_ context.Context, key string, value []byte, revision uin
 type memStore map[string]*memKV
 
 func (s memStore) get(state, key string) ([]byte, uint64, bool, error) {
+	if s[state] == nil {
+		return nil, 0, false, nil
+	}
 	v, ok := s[state].values[key]
 	return v, uint64(len(v)), ok, nil
 }
@@ -198,7 +333,7 @@ func putOfTheBus(t *testing.T) {
 		}
 		p.w.put(bucket, key, data)
 	}
-	world(provider.AssignmentsBucket, "novox.nats", map[string]string{"node": "novox", "module": "nats"})
+	placeOn(t, p.w, "novox", "nats")
 	mdigest := strings.Repeat("e", 64)
 	mod, _ := delivery.EncodeModule(delivery.Module{FP2: fp, Manifest: mdigest, Repository: "novox/mesh-catalog", Commit: strings.Repeat("c", 40)})
 	world(delivery.ModulesBucket, "nats", mod)
@@ -254,19 +389,17 @@ func putOfTheBus(t *testing.T) {
 		t.Errorf("a put asked %q: it reads the compositions and asks nobody for one", call)
 	default:
 	}
-	ckey, _ := delivery.ComposedKey("novox", "nats", fp)
-	cd, _ := delivery.EncodeComposedDigest(delivery.ComposedDigest{Digest: digest, Judgement: delivery.JudgedCannot, Words: "the have names no composition"})
-	world(delivery.ControllerComposedBucket, ckey, cd)
-	gkey, _ := delivery.ControllerGrantKey("nats", fp)
-	g, _ := delivery.EncodeControllerGrant(delivery.ControllerGrant{})
-	world(delivery.ControllerGrantsBucket, gkey, g)
+	composes(t, p.w, "novox", digest)
+	gkey, _ := delivery.PartGrantKey("nats", fp)
+	g, _ := delivery.EncodeGrant(delivery.Grant{})
+	world(delivery.PartGrantsBucket, gkey, g)
 	got := step()
 	akey, _ := delivery.RecordAskKey("novox", "nats", digest)
 	if got.Step != delivery.PutPerson || got.Ask != akey {
 		t.Fatalf("composed, the put stands at %s (%s), ask %q", got.Step, got.Words, got.Ask)
 	}
-	a, err := delivery.DecodeAssignerAsk(akey, asksKV.values[akey])
-	if err != nil || a.Ask.Options[0].Level != asks.Approve {
+	a, err := decodeAsk(akey, asksKV.values[akey])
+	if err != nil || a.Ask.Options[0].Level != occ.Approve {
 		t.Fatalf("the ask is %+v, %v; want a yes that approves", a, err)
 	}
 	if _, there := wantsKV.values["want.novox.nats"]; there {
@@ -284,7 +417,7 @@ func putOfTheBus(t *testing.T) {
 	if got.Step != delivery.PutWanted || err != nil || w.FP != fp || w.Composed != digest || !w.Put || !w.Hold {
 		t.Fatalf("snapshotted, the put stands at %s (%s); the want %+v, %v", got.Step, got.Words, w, err)
 	}
-	if call := <-bus.calls; !strings.Contains(call, "warranted") || !strings.Contains(call, a.Ask.ID) {
+	if call := <-bus.calls; !strings.HasPrefix(call, "seat:mesh-hand-acts.warranted ") || !strings.Contains(call, a.Ask.ID) { // ADR 0565 §11: into the seat
 		t.Errorf("the warrant was recorded as %q", call)
 	}
 	world(delivery.AssignerWantsBucket, "want.novox.nats", wantsKV.values["want.novox.nats"])
@@ -314,7 +447,7 @@ func putOfTheBus(t *testing.T) {
 		t.Fatal(err)
 	}
 	again := step()
-	a2, err := delivery.DecodeAssignerAsk(akey, asksKV.values[akey])
+	a2, err := decodeAsk(akey, asksKV.values[akey])
 	if again.Step != delivery.PutPerson || err != nil || a2.Ask.ID == a.Ask.ID {
 		t.Fatalf("put again, it stands at %s (%s); its ask %q, %v; the first ask was %q", again.Step, again.Words, a2.Ask.ID, err, a.Ask.ID)
 	}
@@ -343,12 +476,14 @@ func putOfTheBus(t *testing.T) {
 // the journal, so it is loud with no operator channel.
 func TestAModuleOnNeitherListIsRaisedOnceAndClearedOnce(t *testing.T) {
 	// A pair only one source names is a condition of the same kind (issue 1126): folded here to hold the count.
-	aPairOneSourceNamesAloneGetsNoWantAndOneCondition(t)
+	aPlacementAloneNamesWhereModulesRun(t)
+	// The verb edges a want waits on come from the graph and what runs (ADR 0614 §2, §3): folded here to hold the count.
+	aWantWaitsOnTheVerbEdgesTheGraphKeeps(t)
 	t.Run("gathers", testThePassGathersTheModulesOnNeitherList)
 	p := newPasser(buckets{}, time.Date(2026, 10, 25, 15, 0, 0, 0, time.UTC))
-	var said []asks.Condition
+	var said []oc.Condition
 	failing := true
-	p.say = func(c asks.Condition) error {
+	p.say = func(c oc.Condition) error {
 		if failing {
 			failing = false
 			return errors.New("the channel is away")
@@ -363,7 +498,7 @@ func TestAModuleOnNeitherListIsRaisedOnceAndClearedOnce(t *testing.T) {
 	p.sayNeither(one, nil, nil) // the say fails
 	p.sayNeither(one, nil, nil)
 	p.sayNeither(one, nil, nil)
-	if len(said) != 1 || said[0].State != asks.StateRaised || said[0].Subject.Machine != "g14" || said[0].Subject.ID != "screen-lock" {
+	if len(said) != 1 || said[0].State != occ.StateRaised || said[0].Subject.Machine != "g14" || said[0].Subject.ID != "screen-lock" {
 		t.Fatalf("said = %+v, want one raised condition of screen-lock on g14", said)
 	}
 	if !strings.Contains(strings.Join(logged, "\n"), "screen-lock") {
@@ -372,20 +507,21 @@ func TestAModuleOnNeitherListIsRaisedOnceAndClearedOnce(t *testing.T) {
 	wants := map[string]string{"g14.screen-lock": ""}
 	p.sayNeither(map[string]neitherOne{}, nil, wants)
 	p.sayNeither(map[string]neitherOne{}, nil, wants)
-	if len(said) != 2 || said[1].State != asks.StateCleared || said[1].Key != said[0].Key {
+	if len(said) != 2 || said[1].State != occ.StateCleared || said[1].Key != said[0].Key {
 		t.Errorf("said = %+v, want the condition cleared once under its key", said)
 	}
 	if last := logged[len(logged)-1]; last != "screen-lock on g14 has a want again" {
 		t.Errorf("the clear said %q", last)
 	}
-	// 1945 (the bus bar): a module that leaves neither list with no want is cleared in words saying so, never "has a want again".
-	bus := map[string]neitherOne{"novox.nats": {node: "novox", module: "nats", holding: assign.Holding{Bus: true, Words: "the bus moves only by the operator's put"}}}
+	// 1945: a module that leaves neither list with no want is cleared in words saying so, never "has a want again". The bus is
+	// on neither list by a rule as any module (ADR 0601 §1), nothing for the operator to do.
+	bus := map[string]neitherOne{"novox.nats": {node: "novox", module: "nats", holding: assign.Holding{Rule: delivery.RuleGrant, Words: "no credential"}}}
 	p.sayNeither(bus, nil, nil)
-	if c := said[len(said)-1]; c.State != asks.StateRaised || !strings.HasPrefix(c.Explanation, asks.NeedsYou) || !strings.Contains(c.Explanation, "the bus moves only by the operator's put") {
+	if c := said[len(said)-1]; c.State != occ.StateRaised || !strings.HasPrefix(c.Explanation, occ.NothingToDo) || !strings.Contains(c.Explanation, "rule 6 holds its first want back: no credential") {
 		t.Errorf("the bus's neither condition = %+v", c)
 	}
 	p.sayNeither(map[string]neitherOne{}, nil, map[string]string{"novox.nats": "it is held, and its held condition says so"})
-	if c := said[len(said)-1]; c.State != asks.StateCleared || strings.Contains(c.Resolved, "has a want") {
+	if c := said[len(said)-1]; c.State != occ.StateCleared || strings.Contains(c.Resolved, "has a want") {
 		t.Errorf("a module that left neither list with no want was cleared as %+v", c)
 	}
 	if last := logged[len(logged)-1]; last != "nats on novox is no longer on neither list and has no want: it is held, and its held condition says so" {
@@ -438,7 +574,6 @@ func testThePassGathersTheModulesOnNeitherList(t *testing.T) {
 		{nil, assign.Outcome{Rules: map[string]assign.Holding{"shanks": {Rule: delivery.RuleGrant, Words: "no credential"}}}, "rofi on shanks gets no want: rule 6: no credential"},
 		{nil, wanted, "rofi on shanks has a want"},
 		{map[string]delivery.Want{"shanks": wanted.Wants["shanks"]}, assign.Outcome{}, ""},
-		{nil, assign.Outcome{Rules: map[string]assign.Holding{"shanks": {Bus: true, Words: "the bus moves only by the operator's put"}}}, "rofi on shanks gets no want: the bus moves only by the operator's put"},
 	} {
 		logged = nil
 		p.sayNoWant("rofi", []string{"shanks"}, c.before, c.out)
@@ -448,16 +583,16 @@ func testThePassGathersTheModulesOnNeitherList(t *testing.T) {
 	}
 	// 1496, ADR 0557 §1: a failure that is the node's own (its fingerprint healthy elsewhere, not held) raises the node's condition
 	// once, naming the node, the module, F and the have's words, and clears it once when it ends.
-	var conds []asks.Condition
-	p.say = func(c asks.Condition) error { conds = append(conds, c); return nil }
+	var conds []oc.Condition
+	p.say = func(c oc.Condition) error { conds = append(conds, c); return nil }
 	failing := map[string]assign.NodeFailure{"shanks": {Others: []string{"ace"}, Words: "health failed, phase running: w"}}
 	for i, c := range []struct {
 		failed map[string]assign.NodeFailure
 		state  string // the condition said in this pass, "" for none
 	}{
-		{failing, asks.StateRaised},
+		{failing, occ.StateRaised},
 		{failing, ""},
-		{nil, asks.StateCleared},
+		{nil, occ.StateCleared},
 		{nil, ""},
 	} {
 		conds = nil
@@ -465,7 +600,7 @@ func testThePassGathersTheModulesOnNeitherList(t *testing.T) {
 		switch {
 		case c.state == "" && len(conds) != 0, c.state != "" && (len(conds) != 1 || conds[0].State != c.state):
 			t.Errorf("node failed, pass %d said %+v, want %q", i, conds, c.state)
-		case c.state == asks.StateRaised && (conds[0].Key != "mesh-delivery-assigner.failed-alone.shanks.rofi" ||
+		case c.state == occ.StateRaised && (conds[0].Key != "mesh-delivery-assigner.failed-alone.shanks.rofi" ||
 			!strings.Contains(conds[0].Explanation, "failed on shanks (health failed, phase running: w), while it runs healthy on ace")):
 			t.Errorf("node failed, raised %+v", conds[0])
 		}
@@ -476,7 +611,7 @@ func testThePassGathersTheModulesOnNeitherList(t *testing.T) {
 	p.sayNodeFailed("rofi", fpTest, []string{"shanks"}, assign.Nodes{}, assign.Outcome{NodeFailed: failing}, false)
 	p.sayNodeFailed("rofi", fpTest, nil, assign.Nodes{}, assign.Outcome{}, false)
 	p.sayNodeFailed("rofi", fpTest, nil, assign.Nodes{}, assign.Outcome{}, false)
-	if len(conds) != 2 || conds[1].State != asks.StateCleared || conds[1].Key != "mesh-delivery-assigner.failed-alone.shanks.rofi" {
+	if len(conds) != 2 || conds[1].State != occ.StateCleared || conds[1].Key != "mesh-delivery-assigner.failed-alone.shanks.rofi" {
 		t.Errorf("a node leaving the module said %+v, want one raise and one clear", conds)
 	}
 	known := assign.Nodes{Online: map[string]bool{"ace": true, "g14": false},
@@ -492,11 +627,11 @@ func testThePassGathersTheModulesOnNeitherList(t *testing.T) {
 		conds = nil
 		fresh := newPasser(buckets{}, time.Date(2026, 10, 26, 22, 0, 0, 0, time.UTC))
 		fresh.logf = func(string, ...any) {}
-		fresh.say = func(c asks.Condition) error { conds = append(conds, c); return nil }
+		fresh.say = func(c oc.Condition) error { conds = append(conds, c); return nil }
 		fresh.sayNodeFailed("rofi", fpTest, nil, c.known, assign.Outcome{}, true)
 		var keys []string
 		for _, cond := range conds {
-			if cond.State == asks.StateCleared {
+			if cond.State == occ.StateCleared {
 				keys = append(keys, cond.Key)
 			}
 		}
@@ -513,11 +648,11 @@ func TestTheFirstPassAfterAStartClearsWhatAPreviousProcessRaised(t *testing.T) {
 	t.Run("a held module", testAHeldModuleRaisesNoNeitherAndClearsAStandingOne)
 	wantsKV := &memKV{values: map[string][]byte{}}
 	p := newPasser(buckets{delivery.AssignerWantsBucket: wantsKV, delivery.AssignerAsksBucket: &memKV{values: map[string][]byte{}}}, time.Now())
-	var said []asks.Condition
-	p.say = func(c asks.Condition) error { said = append(said, c); return nil }
+	var said []oc.Condition
+	p.say = func(c oc.Condition) error { said = append(said, c); return nil }
 	mod, _ := delivery.EncodeModule(delivery.Module{FP2: fpTest, Repository: "novox/web", Commit: strings.Repeat("1", 40), Path: delivery.RootPath})
 	p.w.put(delivery.ModulesBucket, "web", mod)
-	p.w.put(provider.AssignmentsBucket, "g14.web", []byte(`{"node":"g14","module":"web","build":"b-1"}`))
+	placeOn(t, p.w, "g14", "web")
 	on, _ := delivery.EncodePresence(delivery.Presence{Online: true})
 	p.w.put(delivery.PresenceBucket, "g14", on)
 	have, _ := delivery.EncodeHave(delivery.Have{FP: fpTest, Phase: delivery.PhaseRunning, Health: delivery.HealthOK})
@@ -528,7 +663,7 @@ func TestTheFirstPassAfterAStartClearsWhatAPreviousProcessRaised(t *testing.T) {
 	p.wants(context.Background())
 	cleared := map[string]bool{}
 	for _, c := range said {
-		if c.State != asks.StateCleared {
+		if c.State != occ.StateCleared {
 			t.Errorf("the first pass raised %+v", c)
 		}
 		cleared[c.Key] = true
@@ -549,13 +684,13 @@ func TestTheFirstPassAfterAStartClearsWhatAPreviousProcessRaised(t *testing.T) {
 // neither condition for it, a neither condition this process raised for it before is cleared, and so is one a previous process
 // raised (the first pass after a start), each once.
 func testAHeldModuleRaisesNoNeitherAndClearsAStandingOne(t *testing.T) {
-	setup := func() (*passer, *[]asks.Condition) {
+	setup := func() (*passer, *[]oc.Condition) {
 		p := newPasser(buckets{delivery.AssignerWantsBucket: &memKV{values: map[string][]byte{}}, delivery.AssignerAsksBucket: &memKV{values: map[string][]byte{}}}, time.Now())
-		said := &[]asks.Condition{}
-		p.say = func(c asks.Condition) error { *said = append(*said, c); return nil }
+		said := &[]oc.Condition{}
+		p.say = func(c oc.Condition) error { *said = append(*said, c); return nil }
 		mod, _ := delivery.EncodeModule(delivery.Module{FP2: fpTest, Repository: "novox/resolved", Commit: strings.Repeat("1", 40), Path: delivery.RootPath})
 		p.w.put(delivery.ModulesBucket, "systemd-resolved", mod)
-		p.w.put(provider.AssignmentsBucket, "shanks.systemd-resolved", []byte(`{"node":"shanks","module":"systemd-resolved","build":"b-1"}`))
+		placeOn(t, p.w, "shanks", "systemd-resolved")
 		on, _ := delivery.EncodePresence(delivery.Presence{Online: true})
 		p.w.put(delivery.PresenceBucket, "shanks", on)
 		have, _ := delivery.EncodeHave(delivery.Have{FP: fpTest, Phase: delivery.PhaseRunning, Health: delivery.HealthFailed})
@@ -566,12 +701,12 @@ func testAHeldModuleRaisesNoNeitherAndClearsAStandingOne(t *testing.T) {
 		return p, said
 	}
 	key := assign.NeitherCondition("shanks", "systemd-resolved", assign.Holding{}, false).Key
-	neithers := func(said []asks.Condition) (raised, cleared int) {
+	neithers := func(said []oc.Condition) (raised, cleared int) {
 		for _, c := range said {
 			if c.Key != key {
 				continue
 			}
-			if c.State == asks.StateRaised {
+			if c.State == occ.StateRaised {
 				raised++
 			} else {
 				cleared++
@@ -619,21 +754,19 @@ func TestAsksOfAFingerprintTheTrunkLeftBehindAreTakenAway(t *testing.T) {
 		name    string
 		trunk   map[string]delivery.Module
 		gone    []string // the keys taken away
-		noDigit bool     // the controller's composition is not read
-		heldAt  string   // the node's want is at this fingerprint, whose composition is digOld
+		noDigit bool     // the node's own composition is not read
 	}{
-		{"the trunk moved on", trunkOf(fpNew), []string{holdOld, holdGone, restOld, recOld}, false, ""},
-		{"the trunk is at the old fingerprint", trunkOf(fpOld), []string{holdNew, holdGone, restNew, recOld}, false, ""},
-		{"the trunk's fingerprint is not read yet", trunkOf(""), []string{holdGone}, false, ""},
-		{"the composition is not read yet", trunkOf(fpNew), []string{holdOld, holdGone, restOld}, true, ""},
-		{"a node held back at the old fingerprint is still asked about its composition", trunkOf(fpNew), []string{holdOld, holdGone, restOld}, false, fpOld},
-		{"the trunk is not read at all", nil, nil, false, ""},
+		{"the trunk moved on", trunkOf(fpNew), []string{holdOld, holdGone, restOld, recOld}, false},
+		{"the trunk is at the old fingerprint", trunkOf(fpOld), []string{holdNew, holdGone, restNew, recOld}, false},
+		{"the trunk's fingerprint is not read yet", trunkOf(""), []string{holdGone}, false},
+		{"the composition is not read yet", trunkOf(fpNew), []string{holdOld, holdGone, restOld}, true},
+		{"the trunk is not read at all", nil, nil, false},
 	} {
 		t.Run(c.name, func(t *testing.T) {
 			asksKV, wantsKV := &memKV{values: map[string][]byte{}}, &memKV{values: map[string][]byte{}}
 			p := newPasser(buckets{delivery.AssignerAsksBucket: asksKV, delivery.AssignerWantsBucket: wantsKV}, time.Now())
-			var said []asks.Condition
-			p.say = func(c asks.Condition) error { said = append(said, c); return nil }
+			var said []oc.Condition
+			p.say = func(c oc.Condition) error { said = append(said, c); return nil }
 			for _, key := range all {
 				k, _ := delivery.ParseAnyAskKey(key)
 				var a delivery.AssignerAsk
@@ -647,39 +780,27 @@ func TestAsksOfAFingerprintTheTrunkLeftBehindAreTakenAway(t *testing.T) {
 				default:
 					a = assign.BackupAsk(key, k.Node, k.Module, k.FP, digOld, "w", 2, time.Now())
 				}
-				v, err := delivery.EncodeAssignerAsk(key, a)
+				v, err := assign.EncodeAsk(key, a)
 				if err != nil {
 					t.Fatal(err)
 				}
 				asksKV.values[key] = v
 				p.w.put(delivery.AssignerAsksBucket, key, v)
 			}
+			placeOn(t, p.w, "novox", "web") // a placed node composes its own: the digest its have names
 			if !c.noDigit {
-				ckey, _ := delivery.ComposedKey("novox", "web", fpNew)
-				v, _ := delivery.EncodeComposedDigest(delivery.ComposedDigest{Digest: digNew, Judgement: delivery.JudgedUnchanged})
-				p.w.put(delivery.ControllerComposedBucket, ckey, v)
-				okey, _ := delivery.ComposedKey("novox", "web", fpOld)
-				old, _ := delivery.EncodeComposedDigest(delivery.ComposedDigest{Digest: digNew, Judgement: delivery.JudgedUnchanged})
-				if c.heldAt != "" {
-					old, _ = delivery.EncodeComposedDigest(delivery.ComposedDigest{Digest: digOld, Judgement: delivery.JudgedUnchanged})
-				}
-				p.w.put(delivery.ControllerComposedBucket, okey, old)
-			}
-			if c.heldAt != "" {
-				wkey, _ := delivery.WantKey("novox", "web")
-				w, _ := delivery.EncodeWant(delivery.Want{FP: c.heldAt, Composed: digOld})
-				p.w.put(delivery.AssignerWantsBucket, wkey, w)
+				composes(t, p.w, "novox", digNew)
 			}
 			heldOld, _ := delivery.HeldKey("web", fpOld)
 			wantsKV.values[heldOld] = []byte("x")
 			p.w.put(delivery.AssignerWantsBucket, heldOld, []byte("x"))
-			firstAsk, _ := delivery.DecodeAssignerAsk(holdOld, asksKV.values[holdOld])
+			firstAsk, _ := decodeAsk(holdOld, asksKV.values[holdOld])
 			p.staleAsks(context.Background(), c.trunk)
 			// the held record and condition of a fingerprint whose hold ask went are taken away with it
 			heldOld, _ = delivery.HeldKey("web", fpOld)
 			_, heldThere := wantsKV.values[heldOld]
-			cleared := slices.ContainsFunc(said, func(c asks.Condition) bool {
-				return c.Key == assign.HeldCondition("web", fpOld, "", "", false, false).Key && c.State == asks.StateCleared
+			cleared := slices.ContainsFunc(said, func(c oc.Condition) bool {
+				return c.Key == assign.HeldCondition("web", fpOld, "", "", false, false).Key && c.State == occ.StateCleared
 			})
 			if gone := slices.Contains(c.gone, holdOld); !heldThere || cleared != gone {
 				t.Errorf("hold ask of the old fingerprint gone = %v: its held record stays = %v (must), its condition cleared = %v", gone, heldThere, cleared)
@@ -696,8 +817,8 @@ func TestAsksOfAFingerprintTheTrunkLeftBehindAreTakenAway(t *testing.T) {
 				p.now = func() time.Time { return time.Now().Add(time.Hour) }
 				p.holdAsk(context.Background(), "web", fpOld, nil)
 				p.heldCondition(context.Background(), "web", fpOld, nil, false)
-				again, err := delivery.DecodeAssignerAsk(holdOld, asksKV.values[holdOld])
-				raised := slices.ContainsFunc(said, func(c asks.Condition) bool { return c.State == asks.StateRaised })
+				again, err := decodeAsk(holdOld, asksKV.values[holdOld])
+				raised := slices.ContainsFunc(said, func(c oc.Condition) bool { return c.State == occ.StateRaised })
 				if err != nil || again.Ask.ID == firstAsk.Ask.ID || !raised {
 					t.Errorf("the trunk returned to the held fingerprint: ask %q (first %q, %v), condition raised again = %v", again.Ask.ID, firstAsk.Ask.ID, err, raised)
 				}
@@ -708,9 +829,9 @@ func TestAsksOfAFingerprintTheTrunkLeftBehindAreTakenAway(t *testing.T) {
 	t.Run("a clear that failed to be said is said at the next pass, and the ask goes after it", func(t *testing.T) {
 		asksKV, wantsKV := &memKV{values: map[string][]byte{}}, &memKV{values: map[string][]byte{}}
 		p := newPasser(buckets{delivery.AssignerAsksBucket: asksKV, delivery.AssignerWantsBucket: wantsKV}, time.Now())
-		var said []asks.Condition
+		var said []oc.Condition
 		fail := true
-		p.say = func(c asks.Condition) error {
+		p.say = func(c oc.Condition) error {
 			if fail {
 				fail = false
 				return errors.New("router unreachable")
@@ -719,7 +840,7 @@ func TestAsksOfAFingerprintTheTrunkLeftBehindAreTakenAway(t *testing.T) {
 			return nil
 		}
 		a := assign.HoldAsk(holdOld, "web", fpOld, "novox", "w", 1, time.Now())
-		v, err := delivery.EncodeAssignerAsk(holdOld, a)
+		v, err := assign.EncodeAsk(holdOld, a)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -730,7 +851,7 @@ func TestAsksOfAFingerprintTheTrunkLeftBehindAreTakenAway(t *testing.T) {
 			t.Fatalf("after a failed clear: ask left = %v, conditions said = %d; want the ask kept and nothing said", there, len(said))
 		}
 		p.staleAsks(context.Background(), trunkOf(fpNew))
-		if _, there := asksKV.values[holdOld]; there || len(said) != 1 || said[0].State != asks.StateCleared {
+		if _, there := asksKV.values[holdOld]; there || len(said) != 1 || said[0].State != occ.StateCleared {
 			t.Errorf("at the next pass: ask left = %v, conditions said = %v; want the ask gone and the clear said", there, said)
 		}
 	})
@@ -766,112 +887,88 @@ func mustKey(key string, err error) string {
 func TestARecordAskOfAHeldBackNodeSurvivesPassesAndItsYesMovesTheWant(t *testing.T) {
 	// A placed node's yes comes from its have (issue 1126): folded here to hold the count.
 	aPlacedNodesWantsNameTheBuildAloneAndItsYesComesFromItsHave(t)
+	aReleasesApproveAnswersTheMoveOfItsBuildAlone(t)
+}
+
+// ADR 0601 §1: a placed node's have waiting for a yes to a move of the build alone, to a build an approved release carries, is
+// given its yes by that Approve, the want naming the release, and no record ask is raised; a move that changes a setting or a
+// secret too, one at the build it runs, and one no approved release carries are asked of a person as before.
+func aReleasesApproveAnswersTheMoveOfItsBuildAlone(t *testing.T) {
 	fpOld := delivery.SourcePrefix2 + strings.Repeat("a", 64)
-	revised, was := "sha256:"+strings.Repeat("e", 64), "sha256:"+strings.Repeat("d", 64)
-	asksKV, wantsKV := &memKV{values: map[string][]byte{}}, &memKV{values: map[string][]byte{}}
-	p := newPasser(buckets{delivery.AssignerAsksBucket: asksKV, delivery.AssignerWantsBucket: wantsKV}, time.Now())
-	p.logf = t.Logf
-	put := func(bucket, key string, v []byte) { p.w.put(bucket, key, v) }
-	mod, _ := delivery.EncodeModule(delivery.Module{FP2: fpTest, Repository: "novox/web", Commit: strings.Repeat("1", 40), Path: delivery.RootPath})
-	put(delivery.ModulesBucket, "web", mod) // the trunk's build is not done: rule 1 holds g14 back at fpOld
-	put(provider.AssignmentsBucket, "g14.web", []byte(`{"node":"g14","module":"web","build":"b-1"}`))
-	on, _ := delivery.EncodePresence(delivery.Presence{Online: true})
-	put(delivery.PresenceBucket, "g14", on)
-	have, _ := delivery.EncodeHave(delivery.Have{FP: fpOld, Phase: delivery.PhaseRunning, Health: delivery.HealthOK})
-	put(delivery.HaveBucket, "g14.web", have)
-	wkey, _ := delivery.WantKey("g14", "web")
-	want, _ := delivery.EncodeWant(delivery.Want{FP: fpOld, Composed: was})
-	wantsKV.values[wkey] = want
-	put(delivery.AssignerWantsBucket, wkey, want)
-	ckey, _ := delivery.ComposedKey("g14", "web", fpOld)
-	cd, cerr := delivery.EncodeComposedDigest(delivery.ComposedDigest{Digest: revised, Judgement: delivery.JudgedRecreates, Policy: delivery.PolicyRecord, PolicyFrom: "default", Against: was, Words: "recreates"})
-	if cerr != nil {
-		t.Fatal(cerr)
-	}
-	put(delivery.ControllerComposedBucket, ckey, cd)
-	tkey, _ := delivery.ComposedKey("g14", "web", fpTest) // the trunk's own composition, another digest than the revised one
-	tcd, _ := delivery.EncodeComposedDigest(delivery.ComposedDigest{Digest: "sha256:" + strings.Repeat("f", 64), Judgement: delivery.JudgedUnchanged})
-	put(delivery.ControllerComposedBucket, tkey, tcd)
-	akey, _ := delivery.RecordAskKey("g14", "web", revised)
-	for i := 0; i < 2; i++ {
-		p.wants(context.Background())
-		if _, there := asksKV.values[akey]; !there {
-			t.Fatalf("pass %d: the record ask of the held-back node is not there", i+1)
+	waiting, was := "sha256:"+strings.Repeat("e", 64), "sha256:"+strings.Repeat("d", 64)
+	commit := strings.Repeat("1", 40)
+	for _, c := range []struct {
+		name       string
+		alone      bool
+		at         string // the fingerprint the have runs
+		mergedAt   string // the commit the release merged web at; "" for no merge of the release
+		fpSrc      uint64 // the source revision at which web's fingerprint last changed
+		yes, asked bool
+	}{
+		{"the build alone, its release approved", true, fpOld, commit, 7, true, false},
+		{"a setting changed too", false, fpOld, commit, 7, false, true},
+		{"a setting changed at the build it runs", true, fpTest, commit, 7, false, true},
+		{"no approved release carries it", true, fpOld, "", 7, false, true},
+		{"the release merged another commit", true, fpOld, strings.Repeat("2", 40), 7, false, true},
+		// Its fingerprint last moved at another release's revision, which merged nothing of web: that Approve answers nothing.
+		{"a fingerprint another release moved", true, fpOld, commit, 8, false, true},
+		// Review rounds 1 and 2: moved by a recompute after the release (a toolchain, a package, a base) with no merge, the
+		// indexer writes fp-src 0, not known, though Src is still the release's: asked of a person.
+		{"a fingerprint moved by a recompute after the release", true, fpOld, commit, 0, false, true},
+	} {
+		asksKV := &memKV{values: map[string][]byte{}}
+		p := newPasser(buckets{delivery.AssignerAsksBucket: asksKV}, time.Now())
+		p.logf = t.Logf
+		mod, _ := delivery.EncodeModule(delivery.Module{FP2: fpTest, Repository: "novox/web", Commit: commit, Src: 7, FPSrc: c.fpSrc, Path: delivery.RootPath})
+		p.w.put(delivery.ModulesBucket, "web", mod)
+		src, _ := delivery.EncodeSource(delivery.Source{Group: "feat/web", Heads: map[string]string{"novox/web": commit}})
+		p.w.putEntry(delivery.SourceBucket, delivery.SourceMainKey, src, 7, time.Now())
+		later, _ := delivery.EncodeSource(delivery.Source{Group: "feat/other", Heads: map[string]string{"novox/web": commit, "novox/x": commit}})
+		p.w.putEntry(delivery.SourceBucket, delivery.SourceMainKey, later, 8, time.Now()) // a later merge leaves revision 7's release
+		if c.mergedAt != "" {
+			merge, err := delivery.EncodeMerge(delivery.Merge{Group: "feat/web", Ask: "merge.feat_web.0123456789ab", Pulls: []delivery.MergePull{
+				{Head: delivery.Head{Repository: "novox/web", Number: 3, Head: strings.Repeat("3", 40)}, State: delivery.MergeMerged, Commit: c.mergedAt}}})
+			if err != nil {
+				t.Fatal(err)
+			}
+			p.w.put(delivery.MergesBucket, "feat/web", merge)
+			other, err := delivery.EncodeMerge(delivery.Merge{Group: "feat/other", Ask: "merge.feat_other.0123456789ab", Pulls: []delivery.MergePull{
+				{Head: delivery.Head{Repository: "novox/x", Number: 4, Head: strings.Repeat("4", 40)}, State: delivery.MergeMerged, Commit: commit}}})
+			if err != nil {
+				t.Fatal(err)
+			}
+			p.w.put(delivery.MergesBucket, "feat/other", other)
+		}
+		have, _ := delivery.EncodeHave(delivery.Have{FP: c.at, Composed: was, Phase: delivery.PhaseWaitingYes, Health: delivery.HealthOK,
+			Judgement: delivery.JudgedRecreates, Waits: waiting, Detail: "it recreates web.server", BuildAlone: c.alone})
+		p.w.put(delivery.HaveBucket, "g14.web", have)
+		m := assign.Module{Name: "web", FP: fpTest, Nodes: []string{"g14"}, Self: func(string) bool { return true },
+			Release: func(fp string) (string, bool) { return p.w.release("web", fp) }}
+		out := assign.Outcome{Wants: map[string]delivery.Want{"g14": {FP: fpTest, Self: true}}}
+		p.yeses(context.Background(), "web", m, map[string]delivery.Want{"g14": {FP: fpOld, Self: true}}, &out)
+		w := out.Wants["g14"]
+		if got := w.Yes == waiting && w.Release == "feat/web"; got != c.yes || (!c.yes && (w.Yes != "" || w.Release != "")) {
+			t.Errorf("%s: the want is %+v", c.name, w)
+		}
+		akey, _ := delivery.RecordAskKey("g14", "web", waiting)
+		if _, there := asksKV.values[akey]; there != c.asked {
+			t.Errorf("%s: a record ask raised %v, want %v", c.name, there, c.asked)
 		}
-	}
-	a, err := delivery.DecodeAssignerAsk(akey, asksKV.values[akey])
-	if err != nil {
-		t.Fatal(err)
-	}
-	yes, _ := delivery.EncodeAnswer(delivery.Answer{Option: assign.OptionYes, Warrant: a.Ask.ID + "@2026-10-26T01:00:00Z", Words: "the operator"})
-	put(delivery.AnswersBucket, akey, yes)
-	p.wants(context.Background())
-	got, err := delivery.DecodeWant(wantsKV.values[wkey])
-	if err != nil || got.FP != fpOld || got.Composed != revised {
-		t.Errorf("after the yes the want is %+v (%v), want it at %s naming %s", got, err, fpOld, revised)
-	}
-	if _, there := asksKV.values[akey]; !there {
-		t.Error("the answered record ask was taken away")
 	}
 }
 
-// 1126 (ADR 0549 §5): until the third milestone a pair the controller's assignments and the catalogue's placement do not
-// both name gets no want and one condition, raised once and cleared once both name it; before any placement was read the
-// assignments are the one source and nothing is raised.
-func aPairOneSourceNamesAloneGetsNoWantAndOneCondition(t *testing.T) {
+// 774/S26/AC1 (ADR 0549 §5, ADR 0567 §8): the seat's placement alone names where modules run: no controller state is read, so a
+// module in an assignment only is no module of its node, and before any placement is read nothing is placed.
+func aPlacementAloneNamesWhereModulesRun(t *testing.T) {
 	p := newPasser(buckets{}, time.Date(2026, 10, 26, 18, 0, 0, 0, time.UTC))
-	var said []asks.Condition
-	p.say = func(c asks.Condition) error { said = append(said, c); return nil }
-	assigned := func(node, module string) {
-		raw, _ := json.Marshal(map[string]string{"node": node, "module": module})
-		p.w.put(provider.AssignmentsBucket, node+"."+module, raw)
+	p.w.put("mesh-controller_assignments", "g14.b", []byte(`{"node":"g14","module":"b","build":"b-1"}`)) // read no more
+	if got := p.w.assigned(); len(got) != 0 {
+		t.Fatalf("before any placement: assigned %v", got)
 	}
-	place := func(node string, modules ...string) {
-		pl := delivery.Placement{Node: node}
-		for _, m := range modules {
-			pl.Modules = append(pl.Modules, delivery.PlacedModule{Module: m})
-		}
-		raw, err := delivery.EncodePlacement(pl)
-		if err != nil {
-			t.Fatal(err)
-		}
-		key, _ := delivery.PlacementKey(node)
-		p.w.put(delivery.PlacementBucket, key, raw)
-	}
-	assigned("g14", "a")
-	assigned("g14", "b")
-	if got, _ := p.w.assigned(); !slices.Equal(got["g14"], []string{"a", "b"}) || len(p.sayPlacement(p.w.placementDiffers())) != 0 || len(said) != 0 {
-		t.Fatalf("before any placement: assigned %v, said %v", got, said)
-	}
-	none := func(context.Context, string) ([]byte, error) { return nil, errNotThere }
-	if m := p.w.mesh(context.Background(), none); m.Input != nil || m.InputUnread != "" {
-		t.Errorf("before any placement the check composes over %+v (%q)", m.Input, m.InputUnread)
-	}
-	place("g14", "a", "c")
-	got, _ := p.w.assigned()
-	frozen := p.sayPlacement(p.w.placementDiffers())
-	p.sayPlacement(p.w.placementDiffers())
-	if !slices.Equal(got["g14"], []string{"a"}) || !frozen["g14.b"] || !frozen["g14.c"] || frozen["g14.a"] || len(said) != 2 ||
-		said[0].State != asks.StateRaised || !strings.Contains(said[0].Explanation, "the controller's assignments names b on g14") ||
-		!strings.Contains(said[1].Explanation, "the seat mesh-placement's placement names c on g14") {
-		t.Fatalf("one source alone: assigned %v, frozen %v, said %+v", got, frozen, said)
-	}
-	place("g14", "a", "b", "c")
-	assigned("g14", "c")
-	if frozen := p.sayPlacement(p.w.placementDiffers()); len(frozen) != 0 || len(said) != 4 || said[2].State != asks.StateCleared || said[3].State != asks.StateCleared {
-		t.Errorf("both agree again: frozen %v, said %+v", frozen, said)
-	}
-
-	// 1126 (ADR 0547 §2): placed, the check composes over the input the nodes compose from (frombus), once each placed node
-	// wrote its record; until then it says why and composes the assignments alone.
-	if m := p.w.mesh(context.Background(), none); m.Input != nil || !strings.Contains(m.InputUnread, "g14") {
-		t.Errorf("a placed node with no record: input %+v, unread %q", m.Input, m.InputUnread)
-	}
-	rec, _ := delivery.EncodeHaveNode(delivery.HaveNode{Record: &delivery.NodeRecord{Node: "g14", TunnelKey: "k"}})
-	p.w.put(delivery.HaveBucket, "g14.node", rec)
-	m := p.w.mesh(context.Background(), none)
-	if m.Input == nil || len(m.Input.Nodes) != 1 || !slices.Equal(m.Input.Nodes[0].Assigned, []string{"a", "b", "c"}) || m.Input.Nodes[0].Place.Key != "k" {
-		t.Errorf("the check's input from the bus: %+v (%q)", m.Input, m.InputUnread)
+	placeOn(t, p.w, "g14", "c", "a")
+	placeOn(t, p.w, "n2", "d")
+	if got := p.w.assigned(); !slices.Equal(got["g14"], []string{"a", "c"}) || !slices.Equal(got["n2"], []string{"d"}) || len(got) != 2 {
+		t.Errorf("the placement alone: assigned %v", got)
 	}
 }
 
@@ -887,7 +984,7 @@ func aPlacedNodesWantsNameTheBuildAloneAndItsYesComesFromItsHave(t *testing.T) {
 	put := func(bucket, key string, v []byte) { p.w.put(bucket, key, v) }
 	mod, _ := delivery.EncodeModule(delivery.Module{FP2: fpTest, Repository: "novox/web", Commit: strings.Repeat("1", 40), Path: delivery.RootPath})
 	put(delivery.ModulesBucket, "web", mod) // the trunk's build is not done: rule 1 holds g14 at fpOld
-	put(provider.AssignmentsBucket, "g14.web", []byte(`{"node":"g14","module":"web","build":"b-1"}`))
+	placeOn(t, p.w, "g14", "web")
 	pl, _ := delivery.EncodePlacement(delivery.Placement{Node: "g14", Modules: []delivery.PlacedModule{{Module: "web"}}})
 	put(delivery.PlacementBucket, "placement.g14", pl)
 	on, _ := delivery.EncodePresence(delivery.Presence{Online: true})
@@ -924,7 +1021,26 @@ func aPlacedNodesWantsNameTheBuildAloneAndItsYesComesFromItsHave(t *testing.T) {
 	if _, there := asksKV.values[akey]; !there {
 		t.Fatal("a have waiting for a yes raised no record ask")
 	}
-	a, err := delivery.DecodeAssignerAsk(akey, asksKV.values[akey])
+	// Issue 774, 2026-10-31: the node's own composition is not the digest its have waits on; the ask stays, and a pass that
+	// changes nothing puts nothing: on novox the asks of postgres, keycloak and mongodb were taken away and made again every
+	// 8 s, and a want put unchanged each pass made the node compose again each time.
+	composes(t, p.w, "g14", "sha256:"+strings.Repeat("c", 64))
+	asked := asksKV.values[akey]
+	p.wants(context.Background())
+	if !bytes.Equal(asksKV.values[akey], asked) {
+		t.Fatalf("the record ask the node's have waits on was taken away or made again: %q", asksKV.values[akey])
+	}
+	wantPuts, askPuts := wantsKV.puts, asksKV.puts
+	p.wants(context.Background())
+	if wantsKV.puts != wantPuts || asksKV.puts != askPuts {
+		t.Fatalf("a pass that changed nothing put %d wants and %d asks", wantsKV.puts-wantPuts, asksKV.puts-askPuts)
+	}
+	// Whichever rule asks it, a want put with the value the bucket holds reaches no bucket: each put is a change its node hears.
+	p.put(context.Background(), delivery.AssignerWantsBucket, wkey, func() ([]byte, error) { return wantsKV.values[wkey], nil })
+	if wantsKV.puts != wantPuts {
+		t.Fatalf("a want put unchanged reached the bucket")
+	}
+	a, err := decodeAsk(akey, asksKV.values[akey])
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -944,3 +1060,115 @@ func aPlacedNodesWantsNameTheBuildAloneAndItsYesComesFromItsHave(t *testing.T) {
 		t.Errorf("a pass after the move dropped the yes: %+v", got)
 	}
 }
+
+// 774/S25/AC1 (ADR 0567 §8): an approved placement change is written and followed with its warrant recorded and
+// placement-changed said, and no verb of the controller is called; the refused-call conditions a previous process raised are
+// cleared once, and said again at a later pass while the findings cannot be read.
+func TestAnApprovedPlacementCallsNoControllerVerb(t *testing.T) {
+	p := newPasser(buckets{}, time.Date(2026, 11, 2, 9, 0, 0, 0, time.UTC))
+	bus := &fakeBus{calls: make(chan string, 8)}
+	p.seat = newSeatActs(bus, func() {}, func(string, ...any) {})
+	var said []string
+	p.publish = func(event string, _ any, _ string) error { said = append(said, event); return nil }
+	prop := delivery.PlacementProposal{ID: "p-one", By: "operator@laptop", Why: "move web"}
+	change := delivery.ChangeOf(delivery.Placement{Node: "anchor"}, delivery.Placement{Node: "anchor", Modules: []delivery.PlacedModule{{Module: "web"}}})
+	p.followWrite(prop, delivery.Answer{}, []delivery.PlacementChange{change})
+	if len(bus.calls) != 0 || !slices.Equal(said, []string{delivery.PlacementChangedEvent}) {
+		t.Fatalf("calls = %d, said = %v", len(bus.calls), said)
+	}
+
+	var conds []oc.Condition
+	p.say = func(c oc.Condition) error { conds = append(conds, c); return nil }
+	fails := 1
+	p.findings.Keys = func() ([]string, error) {
+		if fails > 0 {
+			fails--
+			return nil, errors.New("the bucket is not there yet")
+		}
+		return []string{"module.anchor.web.controller-call", "module.laptop.db.controller-pin", "module.anchor.web.neither"}, nil
+	}
+	p.clearStaleCalls()
+	p.clearStaleCalls()
+	p.clearStaleCalls()
+	if len(conds) != 2 || conds[0].State != occ.StateCleared || conds[0].Key != "mesh-delivery-assigner.controller-call.anchor.web" ||
+		conds[1].Key != "mesh-delivery-assigner.controller-pin.laptop.db" {
+		t.Fatalf("the old conditions cleared = %+v", conds)
+	}
+}
+
+// ADR 0614 §2, §3: of what a module invokes, the pass keeps as edges the verbs the graph does not leave out and another
+// module serves; a verb is served once a running healthy build's manifest (the builder's build, the indexer's manifest)
+// serves it, and a build whose manifest cannot be read counts what the graph says its module serves. No graph read: no wait.
+func aWantWaitsOnTheVerbEdgesTheGraphKeeps(t *testing.T) {
+	p := newPasser(buckets{}, time.Now())
+	fp := func(c string) string { return delivery.SourcePrefix2 + strings.Repeat(c, 64) }
+	if p.served(context.Background(), nil, graph.Graph{}, assign.Nodes{}) != nil {
+		t.Error("with no graph read, a want waits on a verb")
+	}
+	for module, n := range map[string]graph.Node{
+		"caller": {FP: fp("c"), Repository: "novox/caller", Invokes: []string{"seat:x.v", "loop.l", "none.t", "caller.own"}, LeftOut: []string{"loop.l"},
+			Serves: []string{"caller.own"}},
+		"server": {FP: fp("e"), Repository: "novox/server", Serves: []string{"seat:x.v", "seat:x.w"}},
+		"loop":   {FP: fp("1"), Repository: "novox/loop", Serves: []string{"loop.l"}},
+		"late":   {FP: fp("2"), Repository: "novox/late", Serves: []string{"late.t"}},
+	} {
+		raw, err := graph.Encode(n)
+		if err != nil {
+			t.Fatal(err)
+		}
+		p.w.put(graph.Bucket, module, raw)
+	}
+	g := p.moduleGraph()
+	if got := keptInvokes(g, "caller"); !slices.Equal(got, []string{"seat:x.v"}) || keptInvokes(g, "unknown") != nil {
+		t.Errorf("the kept verb edges of caller = %v", got)
+	}
+	digest := strings.Repeat("d", 64)
+	man, _ := delivery.EncodeManifest(delivery.Manifest{Module: "server", JSON: `{"module":"server","claims":[{"name":"x","scope":"mesh","serves":["w"]}]}`})
+	get := func(_ context.Context, key string) ([]byte, error) {
+		if key == digest {
+			return man, nil
+		}
+		return nil, errNotThere
+	}
+	build, _ := delivery.EncodeBuilderBuild(delivery.BuilderBuild{State: delivery.BuildDone, Manifest: digest})
+	key, _ := delivery.BuilderBuildKey("server", fp("f"))
+	p.w.put(delivery.BuilderBuildsBucket, key, build)
+	running := delivery.Have{Phase: delivery.PhaseRunning, Health: delivery.HealthOK}
+	at := func(f string) delivery.Have { h := running; h.FP = f; return h }
+	served := p.served(context.Background(), get, g, assign.Nodes{Haves: map[string]map[string]delivery.Have{
+		"g14": {"server": at(fp("f")), "late": at(fp("2"))}}})
+	for v, want := range map[string]bool{"seat:x.w": true, "seat:x.v": false, "late.t": true} {
+		if served(v) != want {
+			t.Errorf("served(%s) = %v, want %v: the running server's manifest serves w alone, late's is not read", v, served(v), want)
+		}
+	}
+	// ADR 0614 §5: bus-state counts as offered only from a healthy build on a node present; the bus module's build on an
+	// offline node offers nothing, and one whose manifest is not read counts its trunk manifest's offer.
+	bus := map[string]catalogue.Manifest{"bus": {Module: "bus", Provides: []catalogue.Offer{{Name: graph.BusState, Scope: catalogue.ScopeMesh}}}}
+	for _, online := range []bool{false, true} {
+		offering := p.offering(context.Background(), get, bus, assign.Nodes{Online: map[string]bool{"n2": online},
+			Haves: map[string]map[string]delivery.Have{"n2": {"bus": at(fp("2"))}}})
+		if offering(graph.BusState) != online {
+			t.Errorf("with the bus module's node online %v, bus-state offered %v", online, offering(graph.BusState))
+		}
+	}
+}
+
+// decodedAsk is an asks-state value with the router's ask it carries decoded (mesh-sdk keeps it as raw JSON).
+type decodedAsk struct {
+	Asking int
+	Ask    oc.Ask
+}
+
+func decodeAsk(key string, data []byte) (decodedAsk, error) {
+	a, ask, err := assign.DecodeAsk(key, data)
+	return decodedAsk{Asking: a.Asking, Ask: ask}, err
+}
+
+func mustAskID(a delivery.AssignerAsk) string {
+	ask, err := assign.AskOf(a)
+	if err != nil {
+		panic(err)
+	}
+	return ask.ID
+}

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/puts.go

@@ -10,9 +10,10 @@ import (
 	"sync"
 	"time"
 
-	"git.novox.be/novox/mesh-sdk/go/asks"
+	occ "git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient"
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/handacts"
 
 	"mesh-delivery-assigner/internal/assign"
 )
@@ -46,6 +47,8 @@ type putActs struct {
 	snapped   map[string]string
 	snapNo    map[string]string
 	warranted map[string]bool
+	// rec records the put's warrant in the hand-act log (ADR 0565 §11).
+	rec       handacts.Recorder
 	warrantNo map[string]string
 	said      map[string]string
 	// snapshot takes the bus's snapshot on node; a variable so a test takes none.
@@ -53,7 +56,7 @@ type putActs struct {
 }
 
 func newPutActs(bus caller, wake func(), logf func(string, ...any)) *putActs {
-	a := &putActs{bus: bus, wake: wake, logf: logf, snapping: map[string]bool{}, snapped: map[string]string{}, snapNo: map[string]string{}, warranted: map[string]bool{}, warrantNo: map[string]string{},
+	a := &putActs{rec: handacts.Recorder{Ask: bus.Call}, bus: bus, wake: wake, logf: logf, snapping: map[string]bool{}, snapped: map[string]string{}, snapNo: map[string]string{}, warranted: map[string]bool{}, warrantNo: map[string]string{},
 		said: map[string]string{}}
 	a.snapshot = a.snapshotTheBus
 	return a
@@ -94,9 +97,9 @@ func (p *passer) puts(ctx context.Context) {
 	if len(all) == 0 {
 		return
 	}
-	assigned, _ := p.w.assigned()
+	assigned := p.w.assigned()
 	trunk := p.w.trunk()
-	get := kvGetter(p.kvs[delivery.ManifestsBucket])
+	get := p.w.getter(delivery.ManifestsBucket) // the indexer's manifests, as its first view and views family say them
 	wanted := p.w.wantsOf()
 	modules := make([]string, 0, len(all))
 	for m := range all {
@@ -183,20 +186,24 @@ func (p *passer) putWorld(node, module string, put delivery.Put, manifest catalo
 	w.Composed, w.Granted = p.composedFor(node, module, put.FP)
 	if d := w.Composed; d != nil {
 		policy := d.Policy
-		if policy == "" {
+		chosen, _ := assign.DecodePolicies(p.w.read(assign.PoliciesBucket))
+		if c, ok := chosen[module]; ok {
+			policy, _, _, _ = catalogue.Upgrade(manifest, &c) // a person's choice at the assigner (ADR 0565 §7)
+		} else if policy == "" {
 			policy, _, _ = catalogue.DerivedUpgrade(manifest)
 		}
 		w.Recorded = policy == catalogue.PolicyRecord
 		if akey, err := delivery.RecordAskKey(node, module, d.Digest); err == nil && put.Ask == akey {
 			// Only this put's own ask counts: an ask (and its answer) of an earlier put under the same key is another asking.
-			if a, err := delivery.DecodeAssignerAsk(akey, p.w.value(delivery.AssignerAsksBucket, akey)); err == nil && a.Asking == assign.PutAsking(put) {
+			if a, ask, err := assign.DecodeAsk(akey, p.w.value(delivery.AssignerAsksBucket, akey)); err == nil && a.Asking == assign.PutAsking(put) {
 				switch {
 				case p.answeredWith(akey, assign.OptionYes):
 					w.Answer = assign.OptionYes
 				case p.answeredWith(akey, assign.OptionNo):
 					w.Answer = assign.OptionNo
 				default:
-					w.AskExpired = !a.Ask.Expires.IsZero() && w.Now.After(a.Ask.Expires)
+					expires := assign.ExpiresAt(ask)
+					w.AskExpired = !expires.IsZero() && w.Now.After(expires)
 				}
 			}
 		}
@@ -213,17 +220,16 @@ func (p *passer) putWorld(node, module string, put delivery.Put, manifest catalo
 
 // composedFor is the composition of module for node at fp and whether the grant at fp names the node's accounts: the one
 // place a put reads them (ADR 0546 clause 4). Today their writer is the controller (mesh-controller_composed and
-// mesh-controller_grants); when composing and grants move out of the controller into delivery's own parts, this reads them
-// from their new owner and nothing else changes.
+// mesh-controller_grants); the grants are the grants part's while the controller's lease is handed away (grantsBucket).
 func (p *passer) composedFor(node, module, fp string) (*delivery.ComposedDigest, bool) {
 	var out *delivery.ComposedDigest
 	if d, ok := p.w.composed(node, module, fp); ok {
 		out = &d
 	}
 	granted := false
-	if gkey, err := delivery.ControllerGrantKey(module, fp); err == nil {
-		if raw := p.w.value(delivery.ControllerGrantsBucket, gkey); raw != nil {
-			if g, err := delivery.DecodeControllerGrant(raw); err == nil {
+	if gkey, err := delivery.PartGrantKey(module, fp); err == nil {
+		if raw := p.w.value(p.w.grantsBucket(), gkey); raw != nil {
+			if g, err := delivery.DecodeGrant(raw); err == nil {
 				granted = g.NamesNode(node, module)
 			}
 		}
@@ -237,13 +243,13 @@ func (p *passer) actOn(ctx context.Context, node, module, id string, w assign.Pu
 		// The put's own ask, written again over one an earlier put left under the key (its asking differs), so the teller
 		// raises it anew under its own id.
 		akey := next.Put.Ask
-		current, err := delivery.DecodeAssignerAsk(akey, p.w.value(delivery.AssignerAsksBucket, akey))
+		current, _, err := assign.DecodeAsk(akey, p.w.value(delivery.AssignerAsksBucket, akey))
 		if err != nil || current.Asking != assign.PutAsking(next.Put) {
 			a, err := assign.PutAsk(akey, node, module, next.Put, *w.Composed, w.Bus, w.Now)
 			if err != nil {
 				p.logf("the ask about putting %s on %s is not written: %v", module, node, err)
 			} else {
-				p.put(ctx, delivery.AssignerAsksBucket, akey, func() ([]byte, error) { return delivery.EncodeAssignerAsk(akey, a) })
+				p.put(ctx, delivery.AssignerAsksBucket, akey, func() ([]byte, error) { return assign.EncodeAsk(akey, a) })
 			}
 		}
 	}
@@ -252,15 +258,15 @@ func (p *passer) actOn(ctx context.Context, node, module, id string, w assign.Pu
 	}
 }
 
-// performs checks that the act about to be performed is the one the yes of the ask at key bound (asks.Option.Performs).
-func (p *passer) performs(key string, act asks.Act) error {
-	a, err := delivery.DecodeAssignerAsk(key, p.w.value(delivery.AssignerAsksBucket, key))
+// performs checks that the act about to be performed is the one the yes of the ask at key bound (occ.Performs).
+func (p *passer) performs(key string, act occ.Act) error {
+	_, ask, err := assign.DecodeAsk(key, p.w.value(delivery.AssignerAsksBucket, key))
 	if err != nil {
 		return fmt.Errorf("the ask %s cannot be read: %w", key, err)
 	}
-	for _, o := range a.Ask.Options {
+	for _, o := range ask.Options {
 		if o.ID == assign.OptionYes {
-			return o.Performs(act)
+			return occ.Performs(o, act)
 		}
 	}
 	return fmt.Errorf("the ask %s offers no yes", key)
@@ -382,8 +388,9 @@ func (a *putActs) snapshotTheBus(ctx context.Context, node, module string) (stri
 	}
 }
 
-// warrant records once, in the controller's hand-act log, that the bus's want was written on the operator's warrant: the
-// router's record of the teller's ask says who chose and how (ADR 0274).
+// warrant records once, in the hand-act log (the seat mesh-hand-acts', or the controller's while that seat has no holder and
+// the controller holds its lease, ADR 0565 §11), that the bus's want was written on the operator's warrant: the router's
+// record of the teller's ask says who chose and how (ADR 0274).
 func (a *putActs) warrant(id, ask string) {
 	a.mu.Lock()
 	if a.warranted[id] {
@@ -393,10 +400,10 @@ func (a *putActs) warrant(id, ask string) {
 	a.warranted[id] = true
 	a.mu.Unlock()
 	go func() {
-		if _, err := a.bus.Call("seat:"+catalogue.ControllerSeatName+".warranted", map[string]any{"asker": delivery.TellerModule, "ask": ask}); err != nil {
+		if _, err := a.rec.RecordWarrant(delivery.TellerModule, ask); err != nil {
 			a.logf("the put's warrant %s is not recorded in the hand-act log: %v", ask, err)
 			a.mu.Lock()
-			a.warrantNo[id] = fmt.Sprintf("the warrant %s is not recorded in the controller's hand-act log: %v", ask, err)
+			a.warrantNo[id] = fmt.Sprintf("the warrant %s is not recorded in the hand-act log: %v", ask, err)
 			a.mu.Unlock()
 			a.wake()
 		}

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/seat.go

@@ -7,23 +7,21 @@ import (
 	"fmt"
 	"maps"
 	"reflect"
+	"slices"
 	"sort"
 	"strings"
-	"sync"
 	"time"
 
 	"github.com/nats-io/nats.go"
 	"github.com/nats-io/nats.go/jetstream"
 
-	"git.novox.be/novox/mesh-sdk/go/asks"
-	"git.novox.be/novox/mesh-sdk/go/catalogue"
-	"git.novox.be/novox/mesh-sdk/go/compose"
-	"git.novox.be/novox/mesh-sdk/go/compose/frombus"
-	"git.novox.be/novox/mesh-sdk/go/compose/judge"
+	occ "git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/handacts"
 	"git.novox.be/novox/mesh-sdk/go/process"
 
 	"mesh-delivery-assigner/internal/assign"
+	"mesh-delivery-assigner/internal/judge"
 )
 
 // The seat mesh-placement's holder in the assigner's process (novox/hq ADR 0567 §2-§8): each pass follows every open
@@ -57,128 +55,66 @@ func streamPublisher(ctx context.Context, js jetstream.JetStream, node string) p
 	}
 }
 
-// seatActs keeps what the seat's calls of the controller came to while this process runs: the export read again at a
-// seed's warrant, and each call that keeps the controller's assignments in step (§8).
+// seatActs keeps the seat's acts while this process runs: the warrant recorded in the hand-act log. The seat calls no verb of
+// the controller: placement is the one source (ADR 0567 §8, issue 774).
 type seatActs struct {
-	mu     sync.Mutex
-	bus    caller
-	wake   func()
-	logf   func(string, ...any)
-	export map[string]exportCheck
-	// calls is, by pair (node and module, or node and provision for a pin), what the last call for it came to.
-	calls map[string]string
-}
-
-// exportCheck is the export read again for one proposal: running, its answer, or why it was not read.
-type exportCheck struct {
-	running bool
-	export  map[string]delivery.Placement
-	err     string
+	bus  caller
+	wake func()
+	logf func(string, ...any)
+	// rec records the seat's acts in the hand-act log (ADR 0565 §11).
+	rec handacts.Recorder
 }
 
 func newSeatActs(bus caller, wake func(), logf func(string, ...any)) *seatActs {
-	return &seatActs{bus: bus, wake: wake, logf: logf, export: map[string]exportCheck{}, calls: map[string]string{}}
+	return &seatActs{bus: bus, wake: wake, logf: logf, rec: handacts.Recorder{Ask: bus.Call}}
 }
 
-// exportOf is the export read again for a proposal, asked once in the background.
-func (a *seatActs) exportOf(id string) exportCheck {
-	a.mu.Lock()
-	defer a.mu.Unlock()
-	if c, ok := a.export[id]; ok {
-		return c
-	}
-	a.export[id] = exportCheck{running: true}
-	go func() {
-		defer a.wake()
-		raw, err := a.bus.Call(exportCall, map[string]any{})
-		c := exportCheck{}
-		if err != nil {
-			c.err = "the controller's placement-export did not answer: " + err.Error()
-		} else if c.export, err = assign.ExportOf(raw); err != nil {
-			c.err = err.Error()
-		}
-		a.mu.Lock()
-		a.export[id] = c
-		a.mu.Unlock()
-	}()
-	return exportCheck{running: true}
-}
-
-// forget drops what is kept of a proposal's export, so a later warrant reads it again.
-func (a *seatActs) forget(id string) {
-	if a == nil {
-		return
-	}
-	a.mu.Lock()
-	delete(a.export, id)
-	a.mu.Unlock()
-}
-
-// record records once, in the controller's hand-act log, that placement was written on the operator's warrant (§5): the
-// router's record of the teller's ask says who chose and how (ADR 0274).
+// record records once, in the hand-act log, that placement was written on the operator's warrant (§5): the router's
+// record of the teller's ask says who chose and how (ADR 0274). The log is the seat mesh-hand-acts' from its delivery, and
+// the controller's while that seat has no holder (ADR 0565 §11, handacts.Recorder).
 func (a *seatActs) record(warrant string) {
 	if a == nil || warrant == "" {
 		return
 	}
 	ask, _, _ := strings.Cut(warrant, "@")
 	go func() {
-		if _, err := a.bus.Call("seat:"+catalogue.ControllerSeatName+".warranted", map[string]any{"asker": delivery.TellerModule, "ask": ask}); err != nil {
+		if taken, err := a.rec.RecordWarrant(delivery.TellerModule, ask); err != nil {
 			a.logf("the placement's warrant %s is not recorded in the hand-act log: %v", ask, err)
+		} else {
+			a.logf("the placement's warrant %s is recorded in the log of %s", ask, taken.Log)
 		}
 	}()
 }
 
-// handAct records a hand-back in the controller's hand-act log (§7).
-func (a *seatActs) handAct(prop delivery.PlacementProposal) {
-	go func() {
-		if _, err := a.bus.Call(handActCall, map[string]any{"what": "mesh-placement hand-back of " + strings.Join(prop.Nodes(), ", "),
-			"why": prop.Why, "cause": "asked by " + prop.By + ", approved by the operator"}); err != nil {
-			a.logf("the hand-back %s is not recorded in the hand-act log: %v", prop.ID, err)
-		}
-	}()
-}
-
-// callAll makes the controller's calls in order in the background, each said in the journal and kept by its pair.
-func (a *seatActs) callAll(calls []assign.ControllerCall) {
-	if len(calls) == 0 {
+// clearStaleCalls clears, once, the conditions of the refused controller calls a previous process raised (findings of the
+// kinds controller-call and controller-pin): the assigner calls no verb of the controller any more (ADR 0567 §8, issue 774),
+// so nothing would clear them. It is tried again at the next pass while the findings cannot be read.
+func (p *passer) clearStaleCalls() {
+	if p.callsCleared || p.say == nil || p.findings.Keys == nil {
 		return
 	}
-	a.mu.Lock()
-	for _, c := range calls {
-		a.calls[c.Node+"."+c.Module] = c.Key() + " is asked"
+	keys, err := p.findings.Keys()
+	if err != nil {
+		p.logf("the findings were not read, so the refused controller calls a previous process raised are cleared at the next pass: %v", err)
+		return
 	}
-	a.mu.Unlock()
-	go func() {
-		defer a.wake()
-		for _, c := range calls {
-			words := c.Key() + " answered"
-			if _, err := a.bus.Call("seat:"+catalogue.ControllerSeatName+"."+c.Verb, c.Args); err != nil {
-				words = c.Key() + " refused: " + err.Error()
+	p.callsCleared = true
+	for _, k := range keys {
+		rest, ok := strings.CutPrefix(k, "module.")
+		if !ok {
+			continue
+		}
+		for _, kind := range []string{assign.KindControllerCall, assign.KindControllerPin} {
+			if pair, ok := strings.CutSuffix(rest, "."+kind); ok {
+				if node, module, two := strings.Cut(pair, "."); two {
+					if err := p.say(assign.CallClearedCondition(kind, node, module)); err != nil {
+						p.callsCleared = false
+						p.logf("the condition of the old %s call for %s on %s could not be cleared, and is cleared at the next pass: %v", kind, module, node, err)
+					}
+				}
 			}
-			a.logf("keeping the controller in step with placement: %s", words)
-			a.mu.Lock()
-			a.calls[c.Node+"."+c.Module] = words
-			a.mu.Unlock()
 		}
-	}()
-}
-
-// callOf is what the last call for a pair came to, "" when none was made.
-func (a *seatActs) callOf(node, module string) string {
-	if a == nil {
-		return ""
 	}
-	a.mu.Lock()
-	defer a.mu.Unlock()
-	return a.calls[node+"."+module]
-}
-
-// withCalls names, on each pair the two sources do not both name, the call the assigner made for it (§8).
-func (p *passer) withCalls(pairs []assign.Pair) []assign.Pair {
-	for i := range pairs {
-		pairs[i].Call = p.seat.callOf(pairs[i].Node, pairs[i].Module)
-	}
-	return pairs
 }
 
 // sayWaits raises, once, that the seat waits for the states not yet bound, and clears it once, when all are.
@@ -188,7 +124,7 @@ func (p *passer) sayWaits(unbound []string) {
 	if p.say == nil || p.said[c.Key] && p.saidWaits == state {
 		return
 	}
-	if c.State == asks.StateCleared && p.saidWaits == "" {
+	if c.State == occ.StateCleared && p.saidWaits == "" {
 		return // nothing was raised by this process
 	}
 	if err := p.say(c); err != nil {
@@ -198,19 +134,10 @@ func (p *passer) sayWaits(unbound []string) {
 	p.said[c.Key], p.saidWaits = true, state
 }
 
-// seatPlacements is every node's placement key and its revision, as the watch holds them.
+// seatPlacements is every node's placement and the revision of its node key (its legacy key's for a node not yet
+// converted), as the watch holds them: the revision a proposal is laid over (§2, research 072 row 37).
 func (p *passer) seatPlacements() (map[string]delivery.Placement, map[string]uint64) {
-	out, revs := map[string]delivery.Placement{}, map[string]uint64{}
-	for key, value := range p.w.read(delivery.PlacementBucket) {
-		node, err := delivery.ParsePlacementKey(key)
-		if err != nil {
-			continue
-		}
-		if pl, err := delivery.DecodePlacement(value); err == nil && pl.Node == node {
-			out[node], revs[node] = pl, p.w.metaOf(delivery.PlacementBucket, key).revision
-		}
-	}
-	return out, revs
+	return p.w.placement.AllRevisions()
 }
 
 // candidatesOf is a proposal's candidates by node, with their keys' revisions and the newest write.
@@ -264,6 +191,7 @@ func (p *passer) placementSeat(ctx context.Context) {
 	if p.saidProposed == nil {
 		p.saidProposed, p.intended = map[string]bool{}, map[string]map[string]map[string]bool{}
 	}
+	p.convertPlacement(ctx)
 	current, revs := p.seatPlacements()
 	ids := make([]string, 0)
 	raws := p.w.read(delivery.PlacementProposalsBucket)
@@ -315,11 +243,16 @@ func (p *passer) ask(ctx context.Context, prop delivery.PlacementProposal, akey,
 		p.logf("the ask about the proposal %s is not written: %v", prop.ID, err)
 		return prop, false
 	}
-	p.put(ctx, delivery.AssignerAsksBucket, akey, func() ([]byte, error) { return delivery.EncodeAssignerAsk(akey, a) })
-	if pk, err := delivery.PulseAskKey(prop.ID); err == nil {
-		p.pulse(ctx, pk, a.Ask.Expires.Sub(p.clock()))
+	placed, err := assign.AskOf(a)
+	if err != nil {
+		p.logf("the ask about the proposal %s is not written: %v", prop.ID, err)
+		return prop, false
 	}
-	prop.State, prop.Ask = delivery.ProposalAsked, a.Ask.ID
+	p.put(ctx, delivery.AssignerAsksBucket, akey, func() ([]byte, error) { return assign.EncodeAsk(akey, a) })
+	if pk, err := delivery.PulseAskKey(prop.ID); err == nil {
+		p.pulse(ctx, pk, assign.ExpiresAt(placed).Sub(p.clock()))
+	}
+	prop.State, prop.Ask = delivery.ProposalAsked, placed.ID
 	return prop, true
 }
 
@@ -333,17 +266,22 @@ func (p *passer) stepProposal(ctx context.Context, prop delivery.PlacementPropos
 		p.endProposal(ctx, prop, prop.Withdrawn)
 		return
 	}
+	if prop.Seed || prop.HandBack {
+		// Adopt and hand-back are gone since the lease write (ADR 0547 §11, ADR 0567 §11): a proposal one left open ends.
+		p.endProposal(ctx, prop, "adopt and hand-back are gone since the lease write: placement is the mesh's alone")
+		return
+	}
+	if prop.Warrant != nil {
+		p.addNode(ctx, prop, revs)
+		return
+	}
 	akey, _ := delivery.PlacementAskKey(prop.ID)
 	again := !prop.Again.IsZero() && (prop.Verdict == nil || prop.Again.After(prop.Verdict.At))
 	if prop.State == delivery.ProposalAsked {
 		askPulse, _ := delivery.PulseAskKey(prop.ID)
 		switch {
 		case p.answeredWith(akey, assign.OptionYes):
-			if prop.HandBack {
-				p.handBack(ctx, prop, akey, revs)
-			} else {
-				p.warranted(ctx, prop, rev, akey, current, revs)
-			}
+			p.warranted(ctx, prop, rev, akey, current, revs)
 			return
 		case p.answeredWith(akey, assign.OptionNo):
 			p.endProposal(ctx, prop, "declined by the operator")
@@ -353,19 +291,6 @@ func (p *passer) stepProposal(ctx context.Context, prop delivery.PlacementPropos
 			return
 		}
 	}
-	if prop.HandBack {
-		// The operator's alone (§7): no node answers it; its ask is raised at once, and again on again.
-		if prop.State != delivery.ProposalAsked || again {
-			brief := fmt.Sprintf("%s (asked by %s): every node's placement key is deleted, %s, and each node returns to the "+
-				"controller's compositions; the history is kept", prop.Why, prop.By, strings.Join(prop.Nodes(), ", "))
-			now := p.clock().UTC()
-			prop.Verdict = &delivery.PlacementVerdict{State: delivery.VerdictPass, At: now}
-			if prop, ok := p.ask(ctx, prop, akey, brief); ok {
-				p.writeProposal(ctx, prop, rev)
-			}
-		}
-		return
-	}
 	if moved(prop, revs) {
 		p.layAgain(ctx, prop, rev, current, revs, "a key it was laid over moved since")
 		return
@@ -432,54 +357,35 @@ func moved(prop delivery.PlacementProposal, revs map[string]uint64) bool {
 	return false
 }
 
-// intended is, by proposal and the revisions it was laid over, what Intended computed, kept while this process runs.
+// intendedOf is, by proposal and the revisions it was laid over, what Intended computed, kept while this process runs.
 func (p *passer) intendedOf(prop delivery.PlacementProposal, current map[string]delivery.Placement, cands map[string]delivery.PlacementCandidate) map[string]map[string]bool {
 	key := fmt.Sprint(prop.ID, prop.Base)
 	if got, ok := p.intended[key]; ok {
 		return got
 	}
-	got, _, _ := p.compute(prop, current, cands)
+	got, _ := p.compute(prop, current, cands)
 	p.intended[key] = got
 	return got
 }
 
-// compute composes every node with the current placement and with the proposal laid over it (judge.Intended).
-func (p *passer) compute(prop delivery.PlacementProposal, current map[string]delivery.Placement, cands map[string]delivery.PlacementCandidate) (map[string]map[string]bool, []string, []string) {
+// compute is what the proposal changes on each node by its placement, and the nodes that answer it: every node with a
+// placement or a record (judge.Intended, ADR 0593 §8). The holder composes nothing: each node says what its compositions
+// change in its answer.
+func (p *passer) compute(prop delivery.PlacementProposal, current map[string]delivery.Placement, cands map[string]delivery.PlacementCandidate) (map[string]map[string]bool, []string) {
 	laid := map[string]*delivery.Placement{}
 	for _, node := range prop.Nodes() {
 		if c, ok := cands[node]; ok && !c.Reached {
 			laid[node] = c.Placement
 		}
 	}
-	get := kvGetter(p.kvs[delivery.ManifestsBucket])
-	r := worldReader{w: p.w, manifests: get}
-	var now, with *compose.Input
-	if in, err := frombus.Input(context.Background(), r, frombus.Mesh{}, frombus.Scope{Every: true}); err == nil {
-		now = &in
-	}
-	if in, err := frombus.Input(context.Background(), r, frombus.Mesh{}, frombus.Scope{Every: true, Placements: laid}); err == nil {
-		with = &in
-	}
 	nodes := map[string]bool{}
 	for n := range current {
 		nodes[n] = true
 	}
-	if records, err := r.Records(context.Background()); err == nil {
-		for n := range records {
-			nodes[n] = true
-		}
+	for n := range p.w.records() {
+		nodes[n] = true
 	}
-	names := make([]string, 0, len(nodes))
-	for n := range nodes {
-		names = append(names, n)
-	}
-	fps := map[string]string{}
-	for name, m := range p.w.trunk() {
-		if m.FP2 != "" {
-			fps[name] = m.FP2
-		}
-	}
-	return judge.Intended(now, with, current, laid, names, fps)
+	return judge.Intended(current, laid, slices.Sorted(maps.Keys(nodes)))
 }
 
 // mustAnswer finds the nodes the proposal must hear from (§3), writes a reached candidate for each whose key it does not
@@ -490,7 +396,7 @@ func (p *passer) mustAnswer(ctx context.Context, prop delivery.PlacementProposal
 			return // the verbs write the candidates before the proposal: wait to hear them
 		}
 	}
-	intended, must, notes := p.compute(prop, current, cands)
+	intended, must := p.compute(prop, current, cands)
 	p.intended[fmt.Sprint(prop.ID, prop.Base)] = intended
 	for _, node := range must {
 		if _, ok := cands[node]; ok {
@@ -512,9 +418,6 @@ func (p *passer) mustAnswer(ctx context.Context, prop delivery.PlacementProposal
 		}
 	}
 	prop.Must = must
-	if len(notes) > 0 {
-		prop.Words = strings.TrimPrefix(prop.Words+"; "+strings.Join(notes, "; "), "; ")
-	}
 	p.writeProposal(ctx, prop, rev)
 }
 
@@ -523,8 +426,7 @@ func (p *passer) mustAnswer(ctx context.Context, prop delivery.PlacementProposal
 func (p *passer) layAgain(ctx context.Context, prop delivery.PlacementProposal, rev uint64, current map[string]delivery.Placement, revs map[string]uint64, why string) {
 	held, recorded := p.lays(ctx)
 	again, laid, findings := assign.Propose(assign.ProposeIn{ID: prop.ID, By: prop.By, Why: prop.Why, At: prop.At, Changes: prop.Changes,
-		Current: current, Revisions: revs, Held: held, Recorded: recorded,
-		Seed: prop.Seed, ExportDigest: prop.ExportDigest})
+		Current: current, Revisions: revs, Held: held, Recorded: recorded})
 	if len(findings) > 0 {
 		p.endProposal(ctx, prop, why+", and laid over the keys now it is refused: "+strings.Join(findings, "; "))
 		return
@@ -537,7 +439,6 @@ func (p *passer) layAgain(ctx context.Context, prop delivery.PlacementProposal,
 		p.put(ctx, delivery.PlacementCandidatesBucket, key, func() ([]byte, error) { return delivery.EncodePlacementCandidate(c) })
 	}
 	again.Written, again.Words = p.clock().UTC(), why+": laid again over the keys as they stand, to be judged and asked again"
-	p.seat.forget(prop.ID)
 	p.writeProposal(ctx, again, rev)
 }
 
@@ -550,39 +451,18 @@ func (p *passer) lays(ctx context.Context) (func(string) bool, func(string) bool
 			held[name] = true
 		}
 	}
-	records, _ := worldReader{w: p.w}.Records(ctx)
+	records := p.w.records()
 	return func(m string) bool { return held[m] }, func(n string) bool { _, ok := records[n]; return ok }
 }
 
-// warranted writes an approved proposal (§5): for the seed, after the export is read again and found unchanged (§7);
-// each changed key by compare-and-set at the revision it was laid over; then the warrant recorded, the candidates and the
-// proposal deleted, placement-changed said, and the controller kept in step (§8).
+// warranted writes an approved proposal (§5): each changed key by compare-and-set at the revision it was laid over; then the warrant recorded, the candidates and the
+// proposal deleted, and placement-changed said.
 func (p *passer) warranted(ctx context.Context, prop delivery.PlacementProposal, rev uint64, akey string, current map[string]delivery.Placement, revs map[string]uint64) {
 	if err := p.performs(akey, assign.PlacementAct(prop)); err != nil {
 		p.endProposal(ctx, prop, "its warrant does not bind these changes, so nothing is written: "+err.Error())
 		return
 	}
 	answer, _ := p.w.answer(akey)
-	if prop.Seed {
-		if p.seat == nil {
-			return
-		}
-		c := p.seat.exportOf(prop.ID)
-		switch {
-		case c.running:
-			return // its answer wakes the next pass
-		case c.err != "":
-			if words := "the export cannot be read again at the warrant: " + c.err; prop.Words != words {
-				prop.Words = words
-				p.writeProposal(ctx, prop, rev)
-			}
-			return
-		case delivery.ExportDigest(c.export) != prop.ExportDigest:
-			p.endProposal(ctx, prop, "the controller's export changed since the seed was proposed: the new export is proposed as the seed")
-			p.proposeSeed(ctx, prop, c.export)
-			return
-		}
-	}
 	if moved(prop, revs) {
 		p.layAgain(ctx, prop, rev, current, revs, "a key moved since it was approved, so its warrant is spent")
 		return
@@ -597,32 +477,17 @@ func (p *passer) warranted(ctx context.Context, prop delivery.PlacementProposal,
 		p.logf("the proposal %s cannot be written: %v", prop.ID, err)
 		return
 	}
-	kv := p.kvs[delivery.PlacementBucket]
 	var changes []delivery.PlacementChange
 	writtenLaid := map[string]*delivery.Placement{}
 	after := maps.Clone(current)
 	afterRevs := maps.Clone(revs)
 	for _, w := range writes {
-		var rev2 uint64
-		var err error
-		switch {
-		case w.Value == nil:
-			err = kv.Delete(ctx, w.Key, jetstream.LastRevision(w.Base))
-		default:
-			raw, encErr := delivery.EncodePlacement(*w.Value)
-			if encErr != nil {
-				err = encErr
-			} else if w.Base == 0 {
-				rev2, err = kv.Create(ctx, w.Key, raw)
-			} else {
-				rev2, err = kv.Update(ctx, w.Key, raw, w.Base)
-			}
-		}
+		rev2, err := p.writeNode(ctx, w.Node, w.Value)
 		if err != nil {
 			// Another writer came first (a hand-back): what is written stands and is followed through; the rest is laid
 			// again over the keys as this write left them.
 			p.logf("placement %s is not written at revision %d (%v): the rest of the proposal %s is laid again", w.Key, w.Base, err, prop.ID)
-			p.followWrite(prop, answer, changes, current, writtenLaid)
+			p.followWrite(prop, answer, changes)
 			if rest, ok := assign.Rest(prop, writtenLaid); ok {
 				p.layAgain(ctx, rest, rev, after, afterRevs, "a key moved while it was written, after "+strings.Join(sortedNodes(writtenLaid), ", ")+" were")
 			} else {
@@ -648,22 +513,83 @@ func (p *passer) warranted(ctx context.Context, prop delivery.PlacementProposal,
 	p.deletePulses(ctx, prop.ID)
 	_ = p.kvs[delivery.PlacementProposalsBucket].Delete(ctx, prop.ID)
 	p.w.put(delivery.PlacementProposalsBucket, prop.ID, nil)
-	p.followWrite(prop, answer, changes, current, writtenLaid)
+	p.followWrite(prop, answer, changes)
 }
 
-// followWrite follows the keys a warrant wrote: the warrant recorded, placement-changed said, and, until the lease
-// write, the controller's assignments kept in step for them (§8). The seed calls no controller verb: it is what the
-// controller holds already (§9).
-func (p *passer) followWrite(prop delivery.PlacementProposal, answer delivery.Answer, changes []delivery.PlacementChange,
-	before map[string]delivery.Placement, written map[string]*delivery.Placement) {
+// addNode writes a joining node on the warrant of the enrolment that issued its token (ADR 0587 §7): the operator's Approve
+// was the issue's, so no node is waited on and no ask is raised. The key is created at the revision it was laid over (none: a
+// node with a key is no joining node); the enrolment recorded the warrant in the hand-act log when it was given, so this does
+// not record it again; placement-changed carries the warrant. A key written meanwhile ends the proposal, saying so.
+func (p *passer) addNode(ctx context.Context, prop delivery.PlacementProposal, revs map[string]uint64) {
+	current, _ := p.seatPlacements()
+	if moved(prop, revs) {
+		p.endProposal(ctx, prop, "a key it was laid over was written since: the enrolment proposes the node again")
+		return
+	}
+	laid, findings := delivery.LayChanges(current, prop.Changes)
+	findings = append(findings, assign.ControllerRefusals(prop.Changes, laid)...)
+	node := prop.Changes[0].Node
+	if prop.Changes[0].Op == delivery.OpRemoveNode {
+		p.removeNode(ctx, prop, current, findings)
+		return
+	}
+	value, ok := laid[node]
+	if len(findings) > 0 || !ok {
+		p.endProposal(ctx, prop, "the node cannot be added: "+strings.Join(findings, "; "))
+		return
+	}
+	rev, err := p.writeNode(ctx, node, &value)
+	if err != nil {
+		p.endProposal(ctx, prop, "the node's key was not written: "+err.Error())
+		return
+	}
+	c := delivery.ChangeOf(delivery.Placement{Node: node}, value)
+	c.Before, c.After = prop.Base[node], rev
+	p.deleteCandidates(ctx, prop.ID)
+	p.deletePulses(ctx, prop.ID)
+	_ = p.kvs[delivery.PlacementProposalsBucket].Delete(ctx, prop.ID)
+	p.w.put(delivery.PlacementProposalsBucket, prop.ID, nil)
+	w := prop.Warrant
+	p.sayChanged(prop, delivery.Answer{Option: assign.OptionYes, Warrant: w.Warrant,
+		Words: fmt.Sprintf("the operator approved the machine %s at %s through the enrolment's ask %s", w.Node, w.Address, w.Ask)},
+		[]delivery.PlacementChange{c})
+}
+
+// removeNode deletes the key of a joining node whose enrolment ended unconfirmed, on that enrolment's warrant (the operator's
+// decision of 2026-11-02 01:05): no node answers and no ask is raised, as for its add-node; placement-changed carries the warrant.
+// A node that runs modules or holds seats is no joining node and stays (LayChanges' finding ends the proposal).
+func (p *passer) removeNode(ctx context.Context, prop delivery.PlacementProposal, current map[string]delivery.Placement, findings []string) {
+	node := prop.Changes[0].Node
+	before, ok := current[node]
+	if len(findings) > 0 || !ok {
+		p.endProposal(ctx, prop, "the node cannot be taken off: "+strings.Join(findings, "; "))
+		return
+	}
+	rev, err := p.writeNode(ctx, node, nil)
+	if err != nil {
+		p.endProposal(ctx, prop, "the node's key was not deleted: "+err.Error())
+		return
+	}
+	c := delivery.ChangeOf(before, delivery.Placement{Node: node})
+	c.Before, c.After = prop.Base[node], rev
+	p.deleteCandidates(ctx, prop.ID)
+	p.deletePulses(ctx, prop.ID)
+	_ = p.kvs[delivery.PlacementProposalsBucket].Delete(ctx, prop.ID)
+	p.w.put(delivery.PlacementProposalsBucket, prop.ID, nil)
+	w := prop.Warrant
+	p.sayChanged(prop, delivery.Answer{Option: assign.OptionYes, Warrant: w.Warrant,
+		Words: fmt.Sprintf("the machine %s left placement: its enrolment (ask %s) ended before it confirmed", w.Node, w.Ask)},
+		[]delivery.PlacementChange{c})
+}
+
+// followWrite follows the keys a warrant wrote: the warrant recorded and placement-changed said. No verb of the
+// controller is called: the placement is the one source of where modules run (ADR 0567 §8, issue 774).
+func (p *passer) followWrite(prop delivery.PlacementProposal, answer delivery.Answer, changes []delivery.PlacementChange) {
 	if len(changes) == 0 {
 		return
 	}
 	p.seat.record(answer.Warrant)
 	p.sayChanged(prop, answer, changes)
-	if p.seat != nil && !assign.Leased && !prop.Seed {
-		p.seat.callAll(assign.ControllerCalls(before, written, prop.ID, answer.Warrant))
-	}
 }
 
 func sortedNodes(m map[string]*delivery.Placement) []string {
@@ -675,38 +601,6 @@ func sortedNodes(m map[string]*delivery.Placement) []string {
 	return out
 }
 
-// handBack deletes every key on the operator's warrant (§7) at the revision the hand-back read, records it in the
-// controller's hand-act log and says placement-changed; every node returns to the controller's compositions. A key moved
-// since ends it, and the operator hands back again.
-func (p *passer) handBack(ctx context.Context, prop delivery.PlacementProposal, akey string, revs map[string]uint64) {
-	if err := p.performs(akey, assign.PlacementAct(prop)); err != nil {
-		p.endProposal(ctx, prop, "its warrant does not bind this hand-back, so nothing is deleted: "+err.Error())
-		return
-	}
-	answer, _ := p.w.answer(akey)
-	current, _ := p.seatPlacements()
-	var changes []delivery.PlacementChange
-	for _, node := range prop.Nodes() {
-		key, _ := delivery.PlacementKey(node)
-		if err := p.kvs[delivery.PlacementBucket].Delete(ctx, key, jetstream.LastRevision(prop.Base[node])); err != nil {
-			p.sayChanged(prop, answer, changes)
-			p.endProposal(ctx, prop, fmt.Sprintf("%s moved since the hand-back was asked (%v): hand back again", key, err))
-			return
-		}
-		c := delivery.ChangeOf(current[node], delivery.Placement{Node: node})
-		c.Before = prop.Base[node]
-		changes = append(changes, c)
-	}
-	if p.seat != nil {
-		p.seat.handAct(prop)
-	}
-	p.seat.record(answer.Warrant)
-	_ = p.kvs[delivery.PlacementProposalsBucket].Delete(ctx, prop.ID)
-	p.w.put(delivery.PlacementProposalsBucket, prop.ID, nil)
-	p.deletePulses(ctx, prop.ID)
-	p.sayChanged(prop, answer, changes)
-}
-
 // sayChanged says placement-changed for the keys written.
 func (p *passer) sayChanged(prop delivery.PlacementProposal, answer delivery.Answer, changes []delivery.PlacementChange) {
 	if len(changes) == 0 {
@@ -723,26 +617,6 @@ func (p *passer) sayChanged(prop delivery.PlacementProposal, answer delivery.Ans
 		Warrant: &delivery.PlacementWarrant{Warrant: answer.Warrant, Words: answer.Words, At: at}}, prop.ID+".changed")
 }
 
-// proposeSeed proposes an export as the seed again, by the same proposer and why.
-func (p *passer) proposeSeed(ctx context.Context, was delivery.PlacementProposal, export map[string]delivery.Placement) {
-	held, recorded := p.lays(ctx)
-	now := p.clock()
-	seed, laid, findings := assign.Propose(assign.ProposeIn{ID: delivery.NewProposalID(now), By: was.By, Why: was.Why, At: now,
-		Changes: assign.SeedChanges(export), Current: map[string]delivery.Placement{}, Revisions: map[string]uint64{},
-		Held: held, Recorded: recorded, Seed: true, ExportDigest: delivery.ExportDigest(export)})
-	if len(findings) > 0 {
-		p.logf("the new export is not proposed as the seed: %s", strings.Join(findings, "; "))
-		return
-	}
-	for _, node := range seed.Nodes() {
-		key, _ := delivery.PlacementCandidateKey(seed.ID, node)
-		c := delivery.PlacementCandidate{Proposal: seed.ID, Placement: laid[node]}
-		p.put(ctx, delivery.PlacementCandidatesBucket, key, func() ([]byte, error) { return delivery.EncodePlacementCandidate(c) })
-	}
-	seed.Written = now.UTC()
-	p.writeProposal(ctx, seed, 0)
-}
-
 // endProposal ends a proposal: its ask, its candidates and its key deleted, and placement-withdrawn said carrying it
 // whole with why it ended.
 func (p *passer) endProposal(ctx context.Context, prop delivery.PlacementProposal, why string) {
@@ -758,7 +632,6 @@ func (p *passer) endProposal(ctx context.Context, prop delivery.PlacementProposa
 		return
 	}
 	p.w.put(delivery.PlacementProposalsBucket, prop.ID, nil)
-	p.seat.forget(prop.ID)
 	p.logf("the proposal %s ends: %s", prop.ID, why)
 	p.sayEvent(delivery.PlacementWithdrawnEvent, delivery.PlacementEvent{Proposal: prop, Ended: why}, prop.ID+".withdrawn")
 }
@@ -808,3 +681,73 @@ func (p *passer) sayEvent(event string, body delivery.PlacementEvent, id string)
 		p.logf("%s of %s is not said: %v", event, body.Proposal.ID, err)
 	}
 }
+
+// writeNode writes one node's placement after (nil: none) as its keys (mesh-sdk delivery.PlacementKeys.Writes; research
+// 072 row 37): the module keys that change, each carrying the value it replaces, then the node key, the commit, then the
+// module keys no longer placed. It answers the node key's revision after (0: deleted). A write that fails up to the
+// commit ends it with nothing changed for any reader, the module keys written before it read at their previous values;
+// a delete after the commit that fails leaves a module key the node key does not name, which places nothing and is
+// deleted at the node's next write. Each key written is taken into the world at once, so the next write of the pass
+// reads it.
+func (p *passer) writeNode(ctx context.Context, node string, after *delivery.Placement) (uint64, error) {
+	writes, err := p.w.placement.Writes(node, after)
+	if err != nil {
+		return 0, err
+	}
+	kv := p.kvs[delivery.PlacementBucket]
+	committed, rev := false, uint64(0)
+	for _, w := range writes {
+		got, err := writeKey(ctx, kv, w)
+		if err != nil {
+			if committed {
+				p.logf("placement %s is not deleted after %s's write (%v): it places nothing, and goes at the node's next write", w.Key, node, err)
+				continue
+			}
+			return 0, fmt.Errorf("placement %s at revision %d: %w", w.Key, w.Base, err)
+		}
+		p.w.putEntry(delivery.PlacementBucket, w.Key, w.Value, got, p.clock())
+		if w.Commit {
+			committed, rev = true, got
+		}
+	}
+	return rev, nil
+}
+
+// writeKey makes one write of a placement key by compare-and-set and answers the key's revision after (0: deleted).
+func writeKey(ctx context.Context, kv jetstream.KeyValue, w delivery.PlacementKeyWrite) (uint64, error) {
+	switch {
+	case w.Value == nil:
+		return 0, kv.Delete(ctx, w.Key, jetstream.LastRevision(w.Base))
+	case w.Base == 0:
+		return kv.Create(ctx, w.Key, w.Value)
+	default:
+		return kv.Update(ctx, w.Key, w.Value, w.Base)
+	}
+}
+
+// convertPlacement converts every node the state holds only in the form before, `placement.<node>`, into its node key
+// and module keys (research 072 row 37), once: each node converted is said, and a node whose conversion fails is said
+// and tried again at the next pass. The legacy key is left for the readers not yet delivered; a node key wins over it
+// for every reader that reads both, and it is deleted with the node key when the node's placement is.
+func (p *passer) convertPlacement(ctx context.Context) {
+	if p.convertedAll {
+		return
+	}
+	migrations, err := p.w.placement.Migrations()
+	if err != nil {
+		p.logf("placement: some nodes in the form before cannot be converted, and stay read from it: %v", err)
+	}
+	failed := false
+	for _, node := range slices.Sorted(maps.Keys(migrations)) {
+		before, rev, _ := p.w.placement.Of(node)
+		got, err := p.writeNode(ctx, node, &before)
+		if err != nil {
+			failed = true
+			p.logf("placement: %s is not converted from placement.%s (revision %d) to its node and module keys, and is tried again at the next pass: %v", node, node, rev, err)
+			continue
+		}
+		p.logf("placement: %s converted from placement.%s (revision %d) to %s.node (revision %d) and %d module keys (research 072 row 37); placement.%s stays for readers not yet delivered",
+			node, node, rev, node, got, len(before.Modules), node)
+	}
+	p.convertedAll = !failed && err == nil
+}

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/seat_tools.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"slices"
 	"sort"
 	"strings"
 	"time"
@@ -58,30 +59,34 @@ type keyed struct {
 	Revision  uint64             `json:"revision"`
 }
 
-// placements reads every node's placement and its key's revision.
+// placements reads every node's placement and the revision of its node key (its legacy key's before it is converted),
+// assembled from its keys in either form (delivery.PlacementKeys; research 072 row 37).
 func (s *seatTools) placements() (map[string]delivery.Placement, map[string]uint64, error) {
 	keys, err := s.st.keys(delivery.PlacementState)
 	if err != nil {
 		return nil, nil, fmt.Errorf("placement cannot be listed: %w", err)
 	}
-	out, revs := map[string]delivery.Placement{}, map[string]uint64{}
+	sort.Strings(keys)
+	held := delivery.NewPlacementKeys()
+	var bad []string
 	for _, key := range keys {
-		node, err := delivery.ParsePlacementKey(key)
-		if err != nil {
+		if _, _, _, err := delivery.ParsePlacementKey(key); err != nil {
 			continue
 		}
 		raw, rev, found, err := s.st.get(delivery.PlacementState, key)
 		if err != nil {
-			return nil, nil, fmt.Errorf("placement of %s cannot be read: %w", node, err)
+			return nil, nil, fmt.Errorf("placement key %s cannot be read: %w", key, err)
 		}
 		if !found {
 			continue
 		}
-		p, err := delivery.DecodePlacement(raw)
-		if err != nil {
-			return nil, nil, fmt.Errorf("placement of %s cannot be read: %w", node, err)
+		if _, err := held.Put(key, raw, rev, false); err != nil {
+			bad = append(bad, err.Error())
 		}
-		out[node], revs[node] = p, rev
+	}
+	out, revs := held.AllRevisions()
+	if len(bad) > 0 && len(out) == 0 {
+		return nil, nil, fmt.Errorf("placement cannot be read: %s", strings.Join(bad, "; "))
 	}
 	return out, revs, nil
 }
@@ -201,7 +206,7 @@ func (s *seatTools) doPropose(args map[string]any, by string) (any, error) {
 	}
 	for _, c := range changes {
 		if c.Op == delivery.OpSeed {
-			return nil, errors.New("the seed is adopt's alone: propose takes place, take-off, pin, unpin, hold, unhold, decide and config")
+			return nil, errors.New("the seed is gone with adopt: propose takes place, take-off, pin, unpin, hold, unhold, decide and config")
 		}
 	}
 	current, revs, err := s.placements()
@@ -212,9 +217,16 @@ func (s *seatTools) doPropose(args map[string]any, by string) (any, error) {
 	if err != nil {
 		return nil, err
 	}
+	warrant, err := warrantOf(args["warrant"])
+	if err != nil {
+		return nil, err
+	}
 	now := s.now()
 	p, laid, findings := assign.Propose(assign.ProposeIn{ID: delivery.NewProposalID(now), By: by, Why: arg(args, "why"), At: now,
-		Changes: changes, Current: current, Revisions: revs, Held: held, Recorded: recorded})
+		Changes: changes, Current: current, Revisions: revs, Held: held, Recorded: recorded, Warrant: warrant})
+	if refusal := delivery.AddNodeRefusal(p, moduleOfCaller(by)); refusal != "" {
+		findings = append(findings, refusal)
+	}
 	if len(findings) > 0 {
 		return nil, fmt.Errorf("the proposal is refused: %s", strings.Join(findings, "; "))
 	}
@@ -224,6 +236,42 @@ func (s *seatTools) doPropose(args map[string]any, by string) (any, error) {
 	return proposed{Proposal: p, Follow: followProposal(p.ID)}, nil
 }
 
+// warrantOf reads propose's warrant, an enrolment's for an add-node: an object, given as one or as its text; none is none.
+func warrantOf(v any) (*delivery.AddNodeWarrant, error) {
+	var raw []byte
+	switch w := v.(type) {
+	case nil:
+		return nil, nil
+	case string:
+		if strings.TrimSpace(w) == "" {
+			return nil, nil
+		}
+		raw = []byte(w)
+	default:
+		var err error
+		if raw, err = json.Marshal(w); err != nil {
+			return nil, err
+		}
+	}
+	var out delivery.AddNodeWarrant
+	dec := json.NewDecoder(strings.NewReader(string(raw)))
+	dec.DisallowUnknownFields()
+	if err := dec.Decode(&out); err != nil {
+		return nil, fmt.Errorf("the warrant is no enrolment's warrant {node, address, ask, warrant}: %w", err)
+	}
+	return &out, nil
+}
+
+// moduleOfCaller is the module a caller is, as the runtime proves it, for AddNodeRefusal: mesh-enrolment when the proven
+// caller is that module's (its bus user `<node>.mesh-enrolment`, never a person's `person.mesh-enrolment`), else the caller
+// as proven, which the refusal names.
+func moduleOfCaller(by string) string {
+	if (stdio.Callers{delivery.EnrolmentModule}).Allows(by) {
+		return delivery.EnrolmentModule
+	}
+	return by
+}
+
 // doWithdraw is the verb withdraw (§2): the proposal is marked, and the assigner deletes it and its candidates and says
 // placement-withdrawn carrying it whole.
 func (s *seatTools) doWithdraw(args map[string]any, by string) (any, error) {
@@ -264,88 +312,6 @@ func (s *seatTools) doAgain(args map[string]any) (any, error) {
 	return map[string]any{"proposal": p.ID, "again": p.Again, "follow": followProposal(p.ID)}, nil
 }
 
-// exportCall is the controller's verb the seed is read from, by request and reply on its seat (§7).
-const exportCall = "seat:" + catalogue.ControllerSeatName + ".placement-export"
-
-// doAdopt is the verb adopt (§7): the controller's export proposed whole as the seed.
-func (s *seatTools) doAdopt(args map[string]any, by string) (any, error) {
-	current, _, err := s.placements()
-	if err != nil {
-		return nil, err
-	}
-	if len(current) > 0 {
-		return nil, fmt.Errorf("placement is taken over already (%d keys): propose a change instead, or hand it back first", len(current))
-	}
-	if ids, err := s.st.keys(delivery.PlacementProposalsState); err == nil {
-		for _, id := range ids {
-			if p, err := s.proposal(id); err == nil && p.Seed {
-				return nil, fmt.Errorf("the seed %s is open: withdraw it first, or answer its ask", id)
-			}
-		}
-	}
-	raw, err := s.ask(exportCall, map[string]any{})
-	if err != nil {
-		return nil, fmt.Errorf("the controller's placement-export did not answer: %w", err)
-	}
-	export, err := assign.ExportOf(raw)
-	if err != nil {
-		return nil, err
-	}
-	held, recorded, err := s.lays()
-	if err != nil {
-		return nil, err
-	}
-	now := s.now()
-	p, laid, findings := assign.Propose(assign.ProposeIn{ID: delivery.NewProposalID(now), By: by, Why: arg(args, "why"), At: now,
-		Changes: assign.SeedChanges(export), Current: map[string]delivery.Placement{}, Revisions: map[string]uint64{},
-		Held: held, Recorded: recorded, Seed: true, ExportDigest: delivery.ExportDigest(export)})
-	if len(findings) > 0 {
-		return nil, fmt.Errorf("the seed is refused: %s", strings.Join(findings, "; "))
-	}
-	if err := s.write(p, laid); err != nil {
-		return nil, err
-	}
-	return proposed{Proposal: p, Follow: followProposal(p.ID)}, nil
-}
-
-// handActCall records a hand act in the controller's hand-act log.
-const handActCall = "seat:" + catalogue.ControllerSeatName + ".hand-act"
-
-// doHandBack is the verb hand-back (§7): the operator's alone, so it is asked as a proposal is. It writes a hand-back
-// proposal naming every key at its revision; the assigner raises its authorising ask and, on its warrant, deletes the keys,
-// records the hand act and says placement-changed; every node returns to the controller's compositions.
-func (s *seatTools) doHandBack(args map[string]any, by string) (any, error) {
-	if assign.Leased {
-		return nil, errors.New("placement is the mesh's alone since the lease write: there is no controller to hand it back to")
-	}
-	why := arg(args, "why")
-	if why == "" {
-		return nil, errors.New("hand-back says why: it is recorded with the hand act")
-	}
-	if by == "" {
-		return nil, errors.New("the runtime names no caller: a hand-back is made by someone")
-	}
-	_, revs, err := s.placements()
-	if err != nil {
-		return nil, err
-	}
-	if len(revs) == 0 {
-		return nil, errors.New("there is no placement key to hand back")
-	}
-	now := s.now()
-	p := delivery.PlacementProposal{ID: delivery.NewProposalID(now), By: by, Why: why, At: now.UTC(), Written: now.UTC(),
-		HandBack: true, Base: revs, State: delivery.ProposalAnswering}
-	raw, err := delivery.EncodePlacementProposal(p)
-	if err != nil {
-		return nil, err
-	}
-	if err := s.st.put(delivery.PlacementProposalsState, p.ID, raw); err != nil {
-		return nil, fmt.Errorf("the hand-back is not written: %w", err)
-	}
-	return proposed{Proposal: p, Follow: "the operator is asked to approve it; on the warrant every key is deleted and each " +
-		"node returns to the controller's compositions"}, nil
-}
-
 // placementAnswer is what the verb placement answers.
 type placementAnswer struct {
 	Keys    map[string]keyed `json:"keys,omitempty"`
@@ -368,6 +334,9 @@ type historyEntry struct {
 // doPlacement is the verb placement (§10, §6): one node's key, one module's nodes, or every key; with history, the
 // changes in order from the revisions the state keeps.
 func (s *seatTools) doPlacement(args map[string]any) (any, error) {
+	if arg(args, "seats") == "true" {
+		return s.seats(arg(args, "node"))
+	}
 	all, revs, err := s.placements()
 	if err != nil {
 		return nil, err
@@ -402,26 +371,20 @@ func (s *seatTools) doPlacement(args map[string]any) (any, error) {
 		sort.Strings(nodes)
 	}
 	for _, n := range nodes {
-		key, err := delivery.PlacementKey(n)
+		revisions, err := s.nodeHistory(n)
 		if err != nil {
 			return nil, err
 		}
-		revisions, err := s.st.history(delivery.PlacementState, key)
-		if err != nil {
-			return nil, fmt.Errorf("the history of %s cannot be read: %w", key, err)
-		}
-		var before delivery.Placement
+		var before sketch
 		for _, r := range revisions {
 			e := historyEntry{Node: n, Revision: r.Revision, At: r.At}
-			after := delivery.Placement{}
+			after := sketch{}
 			if r.Op == "" || r.Op == "put" || r.Op == "PUT" {
-				if p, err := delivery.DecodePlacement(r.Value); err == nil {
-					after = p
-				}
+				after = sketchOf(r.Key, r.Value)
 			} else {
 				e.Deleted = true
 			}
-			e.Change = delivery.ChangeOf(before, after)
+			e.Change = after.changeFrom(n, before)
 			e.Change.Before, e.Change.After = 0, r.Revision
 			before = after
 			if module != "" && !strings.Contains(" "+strings.Join(append(append(e.Change.Added, e.Change.Removed...), e.Change.Changed...), " ")+" ", " "+module+" ") {
@@ -522,8 +485,6 @@ func (s *seatTools) tools() []stdio.Tool {
 		catalogue.PlacementVerbPropose:   func(a map[string]any) (any, error) { return s.doPropose(a, stdio.CallerOf(a)) },
 		catalogue.PlacementVerbWithdraw:  func(a map[string]any) (any, error) { return s.doWithdraw(a, stdio.CallerOf(a)) },
 		catalogue.PlacementVerbAgain:     s.doAgain,
-		catalogue.PlacementVerbAdopt:     func(a map[string]any) (any, error) { return s.doAdopt(a, stdio.CallerOf(a)) },
-		catalogue.PlacementVerbHandBack:  func(a map[string]any) (any, error) { return s.doHandBack(a, stdio.CallerOf(a)) },
 	}
 	var out []stdio.Tool
 	for _, v := range seat.Serves {
@@ -531,3 +492,129 @@ func (s *seatTools) tools() []stdio.Tool {
 	}
 	return out
 }
+
+// seats is the verb placement with seats (ADR 0571 §4): who holds each seat and on which node, as the state seat-holders
+// holds it; with node, the keys of seats held on that node.
+func (s *seatTools) seats(node string) (any, error) {
+	keys, err := s.st.keys(delivery.SeatHoldersState)
+	if err != nil {
+		return nil, fmt.Errorf("seat-holders cannot be listed: %w", err)
+	}
+	sort.Strings(keys)
+	out := []delivery.SeatHolders{}
+	for _, key := range keys {
+		raw, _, found, err := s.st.get(delivery.SeatHoldersState, key)
+		if err != nil {
+			return nil, fmt.Errorf("seat-holders %s cannot be read: %w", key, err)
+		}
+		if !found {
+			continue
+		}
+		var sh delivery.SeatHolders
+		if json.Unmarshal(raw, &sh) != nil {
+			continue
+		}
+		if node != "" && sh.Node != node && !slices.ContainsFunc(sh.Holders, func(h delivery.SeatHolder) bool { return h.Node == node }) {
+			continue
+		}
+		out = append(out, sh)
+	}
+	return map[string]any{"seats": out, "holds": len(keys)}, nil
+}
+
+// keyedRevision is one revision of a node's placement key, the key it is of beside it.
+type keyedRevision struct {
+	stdio.StateRevision
+	Key string
+}
+
+// nodeHistory is the revisions of a node's placement, in the order the bus wrote them: its legacy key's
+// `placement.<node>` before it was converted, then its node key's `<node>.node`, whose every revision is one write of
+// the node (research 072 row 37: the node key is a write's commit, so its history is the node's placement history).
+func (s *seatTools) nodeHistory(node string) ([]keyedRevision, error) {
+	legacy, err := delivery.LegacyPlacementKey(node)
+	if err != nil {
+		return nil, err
+	}
+	nodeKey, err := delivery.PlacementNodeKey(node)
+	if err != nil {
+		return nil, err
+	}
+	var out []keyedRevision
+	for _, key := range []string{legacy, nodeKey} {
+		revisions, err := s.st.history(delivery.PlacementState, key)
+		if err != nil {
+			return nil, fmt.Errorf("the history of %s cannot be read: %w", key, err)
+		}
+		for _, r := range revisions {
+			out = append(out, keyedRevision{StateRevision: r, Key: key})
+		}
+	}
+	sort.SliceStable(out, func(i, j int) bool { return out[i].Revision < out[j].Revision })
+	return out, nil
+}
+
+// sketch is a revision of a node's placement as far as its history says a change: each module's digest, and its pins
+// and holdings, which change every module (delivery.ChangeOf).
+type sketch struct {
+	modules  []delivery.PlacementRef
+	nodeWide string
+}
+
+// sketchOf reads one revision of a node key or a legacy key; a value that does not read places nothing.
+func sketchOf(key string, value []byte) sketch {
+	_, _, kind, err := delivery.ParsePlacementKey(key)
+	if err != nil {
+		return sketch{}
+	}
+	wide := func(pins map[string]delivery.Provider, holds []delivery.Holding) string {
+		raw, _ := json.Marshal([]any{pins, holds})
+		return string(raw)
+	}
+	if kind == delivery.PlacementNodeKind {
+		n, err := delivery.DecodePlacementNode(value)
+		if err != nil {
+			return sketch{}
+		}
+		return sketch{modules: n.Modules, nodeWide: wide(n.Pins, n.Holds)}
+	}
+	p, err := delivery.DecodePlacement(value)
+	if err != nil {
+		return sketch{}
+	}
+	out := sketch{nodeWide: wide(p.Pins, p.Holds)}
+	for _, m := range p.Modules {
+		out.modules = append(out.modules, delivery.PlacementRef{Module: m.Module, Digest: m.Digest()})
+	}
+	return out
+}
+
+// changeFrom is what changed from before to s on node, as delivery.ChangeOf says it.
+func (s sketch) changeFrom(node string, before sketch) delivery.PlacementChange {
+	c := delivery.PlacementChange{Node: node}
+	was := map[string]string{}
+	for _, r := range before.modules {
+		was[r.Module] = r.Digest
+	}
+	now := map[string]bool{}
+	nodeWide := before.nodeWide != s.nodeWide && len(before.modules) > 0
+	for _, r := range s.modules {
+		now[r.Module] = true
+		d, ok := was[r.Module]
+		switch {
+		case !ok:
+			c.Added = append(c.Added, r.Module)
+		case nodeWide || d != r.Digest:
+			c.Changed = append(c.Changed, r.Module)
+		}
+	}
+	for _, r := range before.modules {
+		if !now[r.Module] {
+			c.Removed = append(c.Removed, r.Module)
+		}
+	}
+	sort.Strings(c.Added)
+	sort.Strings(c.Removed)
+	sort.Strings(c.Changed)
+	return c
+}

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/seat_tools_test.go

@@ -1,8 +1,12 @@
 package main
 
 import (
+	"context"
 	"encoding/json"
+	"errors"
+	"fmt"
 	"os"
+	"reflect"
 	"slices"
 	"strings"
 	"testing"
@@ -11,6 +15,11 @@ import (
 	stdio "git.novox.be/novox/mesh-sdk/go"
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/health"
+	"git.novox.be/novox/mesh-sdk/go/provisions"
+	"github.com/nats-io/nats.go/jetstream"
+
+	"mesh-delivery-assigner/internal/assign"
 )
 
 func (s memStore) del(state, key string) error {
@@ -26,9 +35,8 @@ func (s memStore) history(state, key string) ([]stdio.StateRevision, error) {
 	return []stdio.StateRevision{{Key: key, Value: v, Revision: uint64(len(v)), Op: "put"}}, nil
 }
 
-// ADR 0567 §2, §7, §10: the seat's seven verbs over the states. propose lays a proposal and writes it with its candidates,
-// or refuses naming every finding and writes nothing; withdraw and again mark it for the holder; adopt proposes the
-// controller's export whole as the seed, once; hand-back records the hand act and deletes every key; placement and
+// ADR 0567 §2, §7, §10: the seat's five verbs over the states. propose lays a proposal and writes it with its candidates,
+// or refuses naming every finding and writes nothing; withdraw and again mark it for the holder; placement and
 // proposals read every state the seat keeps, and history names the stream for what the state no longer keeps.
 func TestTheSeatsVerbs(t *testing.T) {
 	anchor := delivery.Placement{V: delivery.Version, Node: "anchor", Modules: []delivery.PlacedModule{{Module: "web"}}}
@@ -43,32 +51,22 @@ func TestTheSeatsVerbs(t *testing.T) {
 		raw, _ := delivery.EncodeHaveNode(delivery.HaveNode{Record: &delivery.NodeRecord{Node: n}})
 		st[haveState].values[n+".node"] = raw
 	}
-	export, _ := json.Marshal(map[string]any{"anchor": anchor})
 	var asked []string
 	s := newSeatTools(st, func(key string, body any) (json.RawMessage, error) {
 		asked = append(asked, key)
-		if key == exportCall {
-			out, _ := json.Marshal(map[string]any{"ok": true, "output": string(export)})
-			return out, nil
-		}
 		return json.RawMessage(`{"ok":true}`), nil
 	})
 	s.now = func() time.Time { return time.Date(2026, 10, 28, 20, 0, 0, 0, time.UTC) }
 
-	// adopt: the export proposed whole as the seed, once.
-	got, err := s.doAdopt(map[string]any{"why": "take over"}, "operator@laptop")
+	raw, _ := delivery.EncodePlacement(anchor)
+	st[delivery.PlacementState].values["placement.anchor"] = raw
+
+	// withdraw and again mark the proposal; the holder ends or judges it.
+	got, err := s.doPropose(map[string]any{"why": "hold", "changes": `[{"op":"hold","node":"anchor","module":"web","claim":"node-shell","scope":"node"}]`}, "op")
 	if err != nil {
 		t.Fatal(err)
 	}
 	seed := got.(proposed).Proposal
-	if !seed.Seed || seed.ExportDigest != delivery.ExportDigest(map[string]delivery.Placement{"anchor": anchor}) || !slices.Equal(asked, []string{exportCall}) ||
-		len(st[delivery.PlacementCandidatesState].values) != 1 || st[delivery.PlacementProposalsState].values[seed.ID] == nil {
-		t.Fatalf("adopt = %+v, asked %v", seed, asked)
-	}
-	if _, err := s.doAdopt(map[string]any{"why": "again"}, "op"); err == nil || !strings.Contains(err.Error(), "is open") {
-		t.Errorf("a second adopt with a seed open: %v", err)
-	}
-	// withdraw and again mark the proposal; the holder ends or judges it.
 	if _, err := s.doWithdraw(map[string]any{"id": seed.ID, "why": "not yet"}, "op"); err != nil {
 		t.Fatal(err)
 	}
@@ -85,10 +83,8 @@ func TestTheSeatsVerbs(t *testing.T) {
 	st[delivery.PlacementCandidatesState].values = map[string][]byte{}
 
 	// propose: refused whole, naming every finding; a valid move laid over the keys at their revisions.
-	raw, _ := delivery.EncodePlacement(anchor)
-	st[delivery.PlacementState].values["placement.anchor"] = raw
 	if _, err := s.doPropose(map[string]any{"why": "x", "changes": `[{"op":"place","node":"anchor","module":"ghost"},{"op":"hold","node":"anchor","module":"web","claim":"x"}]`}, "op"); err == nil ||
-		!strings.Contains(err.Error(), "ghost") || !strings.Contains(err.Error(), "lease write") || len(st[delivery.PlacementProposalsState].values) != 0 {
+		!strings.Contains(err.Error(), "ghost") || len(st[delivery.PlacementProposalsState].values) != 0 {
 		t.Errorf("a refused proposal: %v", err)
 	}
 	if _, err := s.doPropose(map[string]any{"why": "x", "changes": `[{"op":"swap","node":"anchor"}]`}, "op"); err == nil {
@@ -131,18 +127,374 @@ func TestTheSeatsVerbs(t *testing.T) {
 		}
 	}
 	for _, stream := range raw0.Streams {
-		if !reads["stream "+stream.Name] {
+		// The views family is no seat's stream: the readers of the assigner's states follow it (ADR 0615 §5).
+		if stream.Name != viewsStream && !reads["stream "+stream.Name] {
 			t.Errorf("no verb reads the seat's stream %s", stream.Name)
 		}
 	}
 
-	// hand-back: the operator's alone, written as a hand-back proposal naming every key at its revision, for the assigner
-	// to ask; nothing is deleted by the verb.
-	got, err = s.doHandBack(map[string]any{"why": "back"}, "op")
-	if hb := got.(proposed).Proposal; err != nil || !hb.HandBack || hb.Base["anchor"] != uint64(len(raw)) || len(st[delivery.PlacementState].values) != 1 {
-		t.Errorf("hand-back = %+v, %v", got, err)
+	// Issue 774 (ADR 0567 §8): every kind of change is proposed, and there is no controller to hand placement back to.
+	if _, err := s.doPropose(map[string]any{"why": "hold", "changes": `[{"op":"hold","node":"anchor","module":"web","claim":"node-shell","scope":"node"}]`}, "op"); err != nil {
+		t.Errorf("a hold: %v", err)
 	}
-	if tools := s.tools(); len(tools) != 7 || tools[2].Name != "mesh-placement.propose" || tools[2].Run == nil || tools[2].Input == nil {
+	// 774/S59/AC1 (ADR 0587 §7): an add-node from mesh-enrolment whose warrant names this node and this address is proposed, with
+	// the node a joining one with no record; from another caller, naming another node or address, or with no warrant it is refused.
+	addNode := func(by, warrant string) error {
+		_, err := s.doPropose(map[string]any{"why": "enrolment of ace", "warrant": warrant, "changes": []any{map[string]any{"op": "add-node", "node": "ace",
+			"decided": map[string]any{"address": "10.9.0.2"}, "keys": map[string]any{"overlay": "dHVubmVs"}}}}, by)
+		return err
+	}
+	good := `{"node":"ace","address":"10.9.0.2","ask":"enrol-ace-1","warrant":"enrol-ace-1@2026-10-28T20:00:00Z"}`
+	for _, c := range []struct{ by, warrant, want string }{
+		{"novox.mesh-grants", good, "mesh-enrolment's alone"},
+		{"person.mesh-enrolment", good, "mesh-enrolment's alone"},
+		{"novox.mesh-enrolment", `{"node":"g14","address":"10.9.0.2","ask":"a","warrant":"a@t"}`, "carries the warrant of g14"},
+		{"novox.mesh-enrolment", `{"node":"ace","address":"10.9.0.9","ask":"a","warrant":"a@t"}`, "carries the warrant of ace at 10.9.0.9"},
+		{"novox.mesh-enrolment", "", "carries no warrant"},
+	} {
+		if err := addNode(c.by, c.warrant); err == nil || !strings.Contains(err.Error(), c.want) {
+			t.Errorf("an add-node by %s with warrant %q: %v, want a refusal saying %q", c.by, c.warrant, err, c.want)
+		}
+	}
+	if err := addNode("novox.mesh-enrolment", good); err != nil {
+		t.Errorf("an add-node from mesh-enrolment: %v", err)
+	}
+	// A remove-node (the operator's decision of 2026-11-02 01:05) takes a joining node that never confirmed off placement: from
+	// mesh-enrolment, on the warrant naming that node, of a node running nothing, it is proposed with the node's key to delete;
+	// of a node running modules, or with another node's warrant, it is refused.
+	joiner, _ := delivery.EncodePlacement(delivery.Placement{V: delivery.Version, Node: "joiner", Decided: delivery.NodeDecided{Address: "10.9.0.7"}, Modules: []delivery.PlacedModule{}})
+	st[delivery.PlacementState].values["placement.joiner"] = joiner
+	removeNode := func(node, warrant string) (any, error) {
+		return s.doPropose(map[string]any{"why": "enrolment ended", "warrant": warrant,
+			"changes": []any{map[string]any{"op": "remove-node", "node": node}}}, "novox.mesh-enrolment")
+	}
+	for _, c := range []struct{ node, warrant, want string }{
+		{"anchor", `{"node":"anchor","address":"10.9.0.1","ask":"a","warrant":"a@t"}`, "runs modules or holds seats"},
+		{"joiner", `{"node":"g14","address":"10.9.0.7","ask":"a","warrant":"a@t"}`, "carries the warrant of g14"},
+	} {
+		if _, err := removeNode(c.node, c.warrant); err == nil || !strings.Contains(err.Error(), c.want) {
+			t.Errorf("a remove-node of %s: %v, want a refusal saying %q", c.node, err, c.want)
+		}
+	}
+	if got, err := removeNode("joiner", `{"node":"joiner","address":"10.9.0.7","ask":"a","warrant":"a@t"}`); err != nil {
+		t.Errorf("a remove-node from mesh-enrolment: %v", err)
+	} else if rm := got.(proposed).Proposal; !slices.Equal(rm.Nodes(), []string{"joiner"}) || !slices.Equal(rm.RemovedNodes(), []string{"joiner"}) {
+		t.Errorf("the remove-node proposed %+v", rm)
+	}
+	// 1126/B8: the seat serves its five verbs; adopt and hand-back went with the controller (ADR 0590).
+	if tools := s.tools(); len(tools) != 5 || tools[2].Name != "mesh-placement.propose" || tools[2].Run == nil || tools[2].Input == nil {
+		t.Errorf("the seat's verbs as served: %+v", tools)
+	}
+	t.Run("1953/D4-D6: the seat mesh-wants' upgrade and bus", wantsVerbs)
+	t.Run("1955/L7 (ADR 0571 §6): rule 7 reads the node's own composition; an unplaced node is said", func(t *testing.T) {
+		w := newWorld()
+		fp := delivery.SourcePrefix2 + strings.Repeat("2", 64)
+		pl, _ := delivery.EncodePlacement(delivery.Placement{V: delivery.Version, Node: "ace", Modules: []delivery.PlacedModule{{Module: "web"}}})
+		pkey, _ := delivery.LegacyPlacementKey("ace")
+		w.putEntry(delivery.PlacementBucket, pkey, pl, 1, time.Now())
+		for node, digest := range map[string]string{"ace": "sha256:" + strings.Repeat("a", 64), "g14": ""} {
+			hn, _ := delivery.EncodeHaveNode(delivery.HaveNode{Composed: digest})
+			hk, _ := delivery.HaveNodeKey(node)
+			w.putEntry(delivery.HaveBucket, hk, hn, 1, time.Now())
+		}
+		if d, ok := w.composed("ace", "web", fp); !ok || d.Digest != "sha256:"+strings.Repeat("a", 64) {
+			t.Errorf("ace: %+v %v", d, ok)
+		}
+		if _, ok := w.composed("g14", "web", fp); ok || !slices.Equal(w.unplacedNodes(), []string{"g14"}) {
+			t.Errorf("g14 unplaced: composed %v, unplaced %v", ok, w.unplacedNodes())
+		}
+		findings := map[string][]byte{}
+		p := &passer{w: w, logf: func(string, ...any) {}, findings: assign.Findings{
+			Put:    func(k string, v []byte) error { findings[k] = v; return nil },
+			Delete: func(k string) error { delete(findings, k); return nil }}}
+		p.unplacedFindings()
+		if _, ok := findings[assign.UnplacedKey("g14")]; !ok || len(findings) != 1 {
+			t.Fatalf("findings = %v", findings)
+		}
+		pl2, _ := delivery.EncodePlacement(delivery.Placement{V: delivery.Version, Node: "g14", Modules: []delivery.PlacedModule{{Module: "web"}}})
+		pkey2, _ := delivery.LegacyPlacementKey("g14")
+		w.putEntry(delivery.PlacementBucket, pkey2, pl2, 1, time.Now())
+		p.unplacedFindings()
+		if len(findings) != 0 {
+			t.Errorf("placed again: findings %v", findings)
+		}
+	})
+	t.Run("1955/L7 (ADR 0571 §4): seat-holders is written from placement, only the keys a change moves, and answered by placement seats", func(t *testing.T) {
+		writes := 0
+		kv := &countingKV{memKV: memKV{values: map[string][]byte{}}, writes: &writes}
+		p := &passer{w: newWorld(), logf: t.Logf, kvs: buckets{delivery.SeatHoldersBucket: kv}}
+		place := func(node string, holds ...delivery.Holding) {
+			pl, err := delivery.EncodePlacement(delivery.Placement{V: delivery.Version, Node: node, Modules: []delivery.PlacedModule{{Module: "web"}, {Module: "nats"}}, Holds: holds})
+			if err != nil {
+				t.Fatal(err)
+			}
+			k, _ := delivery.LegacyPlacementKey(node)
+			p.w.putEntry(delivery.PlacementBucket, k, pl, 1, time.Now())
+		}
+		place("ace", delivery.Holding{Claim: "mesh-broker", Scope: "mesh", Module: "nats"}, delivery.Holding{Claim: "node-shell", Scope: "node", Module: "web"})
+		place("g14", delivery.Holding{Claim: "node-shell", Scope: "node", Module: "web"})
+		ctx := context.Background()
+		p.seatHolders(ctx)
+		if writes != 3 || kv.values["mesh-broker"] == nil || kv.values["node-shell.ace"] == nil || kv.values["node-shell.g14"] == nil {
+			t.Fatalf("%d writes: %v", writes, kv.values)
+		}
+		p.seatHolders(ctx)
+		if writes != 3 {
+			t.Errorf("an unchanged placement wrote %d keys", writes-3)
+		}
+		place("g14") // g14 holds nothing now
+		p.seatHolders(ctx)
+		if writes != 3 || kv.values["node-shell.g14"] != nil || kv.values["node-shell.ace"] == nil {
+			t.Errorf("after g14's change: %d writes, %v", writes, kv.values)
+		}
+		st := memStore{delivery.SeatHoldersState: &memKV{values: kv.values}}
+		out, err := newSeatTools(st, nil).seats("ace")
+		if err != nil || len(out.(map[string]any)["seats"].([]delivery.SeatHolders)) != 2 {
+			t.Errorf("seats on ace = %+v, %v", out, err)
+		}
+	})
+	t.Run("research 072 row 37: the form before is converted once, a node is written as its keys, and history reads both", func(t *testing.T) {
+		ctx := context.Background()
+		kv := &revKV{values: map[string][]byte{}, revs: map[string]uint64{}}
+		var logs []string
+		p := &passer{w: newWorld(), kvs: buckets{delivery.PlacementBucket: kv}, now: time.Now,
+			logf: func(f string, a ...any) { logs = append(logs, fmt.Sprintf(f, a...)) }}
+		put := func(key string, value []byte, rev uint64) {
+			p.w.putEntry(delivery.PlacementBucket, key, value, rev, time.Now())
+		}
+		was := delivery.Placement{Node: "anchor", Modules: []delivery.PlacedModule{{Module: "web"}}}
+		raw, _ := delivery.EncodePlacement(was)
+		put("placement.anchor", raw, kv.write("placement.anchor", raw))
+		p.convertPlacement(ctx)
+		if strings.Join(kv.log, " ") != "create anchor.web create anchor.node" || !p.convertedAll ||
+			!strings.Contains(strings.Join(logs, "\n"), "anchor converted from placement.anchor") {
+			t.Fatalf("the conversion wrote %v, said %v", kv.log, logs)
+		}
+		p.convertPlacement(ctx)
+		if len(kv.log) != 2 {
+			t.Errorf("a converted node is converted again: %v", kv.log)
+		}
+		// A write: the module keys, the node key (its commit), the mirror, then the module key no longer placed.
+		after := delivery.Placement{Node: "anchor", Modules: []delivery.PlacedModule{{Module: "shell", Ports: map[string]int{"22": 2222}}}}
+		kv.log = nil
+		rev, err := p.writeNode(ctx, "anchor", &after)
+		if err != nil || strings.Join(kv.log, " ") != "create anchor.shell update anchor.node update placement.anchor delete anchor.web" || rev != kv.revs["anchor.node"] {
+			t.Fatalf("the write = %v, %d, %v", kv.log, rev, err)
+		}
+		if got, _ := p.seatPlacements(); !delivery.SamePlacement(got["anchor"], after) {
+			t.Errorf("the write is not read back at once: %+v", got)
+		}
+		// A commit refused leaves every reader on what stood: the module key written before it carries the value it replaced.
+		kv.refuse, kv.log = "anchor.node", nil
+		moved := delivery.Placement{Node: "anchor", Modules: []delivery.PlacedModule{{Module: "shell", Ports: map[string]int{"22": 2223}}}}
+		if _, err := p.writeNode(ctx, "anchor", &moved); err == nil || strings.Join(kv.log, " ") != "update anchor.shell" {
+			t.Fatalf("a refused commit = %v, %v", kv.log, err)
+		}
+		fresh, err := delivery.PlacementsOf(kv.values)
+		if err != nil || !delivery.SamePlacement(fresh["anchor"], after) {
+			t.Errorf("a reader of the keys after a refused commit reads %+v, %v", fresh["anchor"], err)
+		}
+		kv.refuse = ""
+		// The verb's history reads the form before, then the node key.
+		st := memStore{delivery.PlacementState: &memKV{values: kv.values}}
+		hs := newSeatTools(st, nil)
+		hs.st = historyStore{memStore: st, revisions: map[string][]stdio.StateRevision{
+			"placement.anchor": {{Key: "placement.anchor", Value: raw, Revision: 1, Op: "put"}},
+			"anchor.node":      {{Key: "anchor.node", Value: kv.values["anchor.node"], Revision: 5, Op: "put"}, {Key: "anchor.node", Revision: 9, Op: "del"}},
+		}}
+		pa, err := hs.doPlacement(map[string]any{"node": "anchor", "history": "true"})
+		a, _ := pa.(placementAnswer)
+		if err != nil || len(a.Changes) != 3 || !slices.Equal(a.Changes[0].Change.Added, []string{"web"}) ||
+			!slices.Equal(a.Changes[1].Change.Added, []string{"shell"}) || !slices.Equal(a.Changes[1].Change.Removed, []string{"web"}) ||
+			!a.Changes[2].Deleted || !slices.Equal(a.Changes[2].Change.Removed, []string{"shell"}) {
+			t.Errorf("history = %+v, %v", pa, err)
+		}
+		// No placement: the mirror first, then the node key, then the module keys.
+		kv.log = nil
+		if _, err := p.writeNode(ctx, "anchor", nil); err != nil || strings.Join(kv.log, " ") != "delete placement.anchor delete anchor.node delete anchor.shell" {
+			t.Errorf("the delete = %v, %v", kv.log, err)
+		}
+	})
+	t.Run("1954/D1: a failed provision is the assigner's finding until it is provided", func(t *testing.T) {
+		findings := map[string][]byte{}
+		p := &passer{w: newWorld(), logf: func(string, ...any) {}, kvs: buckets{provisions.ProvisionsBucket: nil}, findings: assign.Findings{
+			Put:    func(k string, v []byte) error { findings[k] = v; return nil },
+			Delete: func(k string) error { delete(findings, k); return nil }}}
+		failed, _ := provisions.Encode(provisions.Provision{Provision: "db", Consumer: provisions.End{Module: "photos", Node: "ace"},
+			Provider: provisions.End{Module: "postgres", Node: "novox"}, State: provisions.Failed, Why: "the role exists already"})
+		p.w.putEntry(provisions.ProvisionsBucket, "ace.photos.db", failed, 1, time.Now())
+		p.kvs[provisions.ProvisionsBucket] = &memKV{}
+		of := p.provisionsOf()
+		if got := of("photos")("ace"); got["ace.photos.db"].State != provisions.Failed {
+			t.Fatalf("provisions = %+v", got)
+		}
+		if _, ok := findings[assign.ProvisionFailedKey("ace.photos.db")]; !ok || len(findings) != 1 {
+			t.Fatalf("findings = %v", findings)
+		}
+		provided, _ := provisions.Encode(provisions.Provision{Provision: "db", Consumer: provisions.End{Module: "photos", Node: "ace"},
+			Provider: provisions.End{Module: "postgres", Node: "novox"}, State: provisions.Provided})
+		p.w.putEntry(provisions.ProvisionsBucket, "ace.photos.db", provided, 2, time.Now())
+		p.provisionsOf()
+		if len(findings) != 0 {
+			t.Errorf("findings after provided = %v", findings)
+		}
+		// A required provision with no key: pulsed with the bound first, said once the pulse expired, ended once keyed.
+		ctx := context.Background()
+		p.kvs[delivery.PlacementPulsesBucket] = &memKV{values: map[string][]byte{}}
+		gone := map[string]bool{"ace.photos.s3": true}
+		p.provisionsMissing(ctx, gone)
+		if !p.pulsing("provision-missing.ace.photos.s3") || len(findings) != 0 {
+			t.Fatalf("first seen: pulsing %v, findings %v", p.pulsing("provision-missing.ace.photos.s3"), findings)
+		}
+		p.provisionsMissing(ctx, gone)
+		if len(findings) != 0 {
+			t.Fatal("said before its bound")
+		}
+		p.w.put(delivery.PlacementPulsesBucket, "provision-missing.ace.photos.s3", nil) // the server expired it
+		p.provisionsMissing(ctx, gone)
+		if _, ok := findings[assign.ProvisionMissingKey("ace.photos.s3")]; !ok {
+			t.Fatalf("past its bound: findings %v", findings)
+		}
+		p.provisionsMissing(ctx, map[string]bool{})
+		if len(findings) != 0 {
+			t.Errorf("keyed again: findings %v", findings)
+		}
+	})
+}
+
+// wantsVerbs (novox/hq ADR 0565 §7, §8, §9): upgrade answers each module's policy and its source; a person's choice is
+// written with who and why, recorded as a hand act in the seat's log and said as policy-changed, and default takes it back;
+// the bus is refused; compare lists each node's composition and the findings; bus names the node behind the indexer's newest.
+func wantsVerbs(t *testing.T) {
+	fpOld, fpNew := delivery.SourcePrefix2+strings.Repeat("1", 64), delivery.SourcePrefix2+strings.Repeat("2", 64)
+	st := memStore{}
+	for _, state := range []string{modulesState, manifestsState, policiesState, haveState, putsState, "findings", delivery.ComposedRead} {
+		st[state] = &memKV{values: map[string][]byte{}}
+	}
+	// ADR 0593 §6, §8: what each node published, every node's bucket as one state: anchor's own composition and its web at
+	// a fingerprint, and laptop's web refused there.
+	webKey, _ := delivery.ComposedKey("anchor", "web", fpNew)
+	refusedKey, _ := delivery.ComposedKey("laptop", "web", fpNew)
+	st[delivery.ComposedRead].values["anchor.node"], _ = delivery.EncodeComposed(delivery.Composed{Node: "anchor"})
+	st[delivery.ComposedRead].values[webKey], _ = delivery.EncodeComposed(delivery.Composed{Node: "anchor", Module: "web", FP: fpNew})
+	st[delivery.ComposedRead].values[refusedKey], _ = delivery.EncodeComposed(delivery.Composed{Node: "laptop", Module: "web", FP: fpNew, Refused: "a required value is unset"})
+	manifest := func(name, extra string) {
+		raw := `{"module":"` + name + `","version":"1"` + extra + `}`
+		digest := delivery.ManifestDigest([]byte(raw))
+		st[manifestsState].values[digest], _ = delivery.EncodeManifest(delivery.Manifest{V: delivery.Version, Module: name, JSON: raw})
+		st[modulesState].values[name], _ = delivery.EncodeModule(delivery.Module{V: delivery.Version, FP2: fpNew, Manifest: digest, Repository: "novox/x", Commit: "c"})
+	}
+	manifest("web", "")
+	manifest("photos", `,"upgrade":{"policy":"record","why":"a person checks the albums"}`)
+	manifest("nats", `,"provides":[{"name":"mesh-bus","scope":"mesh"}],"upgrade":{"policy":"record","why":"its streams"}`)
+	for node, fp := range map[string]string{"anchor": fpOld, "laptop": fpNew} {
+		st[haveState].values[node+".nats"], _ = delivery.EncodeHave(delivery.Have{FP: fp, Phase: delivery.PhaseRunning, Health: delivery.HealthOK})
+	}
+	st[haveState].values["anchor.node"], _ = delivery.EncodeHaveNode(delivery.HaveNode{Composed: "sha256:" + strings.Repeat("c", 64)})
+	var asked []string
+	var said []string
+	w := newWantsTools(st, func(key string, body any) (json.RawMessage, error) {
+		asked = append(asked, key)
+		return json.RawMessage(`{"ok":true}`), nil
+	}, func(event, id string, body any) error { said = append(said, event+" "+id); return nil })
+	policyOf := func(module string) policyRow {
+		out, err := w.doUpgrade(map[string]any{"module": module}, "op")
+		if err != nil {
+			t.Fatal(err)
+		}
+		return out.(map[string]any)["modules"].([]policyRow)[0]
+	}
+	if p := policyOf("photos"); p.Policy != catalogue.PolicyRecord || p.From != catalogue.FromModule {
+		t.Errorf("photos = %+v", p)
+	}
+	if p := policyOf("nats"); p.Policy != catalogue.PolicyRecord || p.From != catalogue.FromModule { // the policy its manifest says (issue 774)
+		t.Errorf("nats = %+v", p)
+	}
+	// compare: each node's own composition is the digest its have names, and the assigner's findings; nothing splits, the
+	// controller being gone (1126/B8).
+	out, _ := w.doUpgrade(map[string]any{"compare": "true"}, "op")
+	if got := out.(map[string]any); got["splits"] != nil || got["findings"] == nil ||
+		got["composed"].(map[string]string)["anchor"] != "sha256:"+strings.Repeat("c", 64) || len(got["composed"].(map[string]string)) != 1 {
+		t.Errorf("compare = %+v", got)
+	}
+	pub, _ := out.(map[string]any)["published"].(map[string][]publishedRow)
+	if a, l := pub["anchor"], pub["laptop"]; len(a) != 2 || a[0].Module != "node" || a[1].Module != "web" || a[1].FP != fpNew ||
+		!strings.HasPrefix(a[1].Digest, "sha256:") || len(l) != 1 || l[0].Refused != "a required value is unset" || l[0].Digest != "" {
+		t.Errorf("published = %+v (unread %v)", pub, out.(map[string]any)["published-unread"])
+	}
+	// Read by watch (issue 1953 L5f): the same answer, each watched state started once, and no get per key of the
+	// large states (the modules, their manifests, the composed record).
+	watches := map[string]int{}
+	byWatch := newWantsTools(st, nil, nil)
+	byWatch.watched = stdio.WatchedStatesOver(func(state string, handle func(stdio.StateChange) error) error {
+		watches[state]++
+		for k, v := range st[state].values {
+			_ = handle(stdio.StateChange{Key: k, Op: stdio.OpPut, Value: v, Current: true})
+		}
+		return nil
+	}, func(state, key string) ([]byte, bool, error) {
+		watches[state+" by key"]++
+		v, ok := st[state].values[key]
+		return v, ok, nil
+	})
+	for range 2 {
+		wout, werr := byWatch.doUpgrade(map[string]any{"compare": "true"}, "op")
+		if werr != nil {
+			t.Fatal(werr)
+		}
+		if got := wout.(map[string]any); got["composed"].(map[string]string)["anchor"] != "sha256:"+strings.Repeat("c", 64) {
+			t.Errorf("compare by watch = %+v", got)
+		}
+	}
+	if n := watches[manifestsState+" by key"]; n == 0 || n > len(st[manifestsState].values) {
+		t.Errorf("the manifests were read by key %d times, want each once", n)
+	}
+	for _, state := range []string{modulesState, haveState, health.FindingsState} {
+		if watches[state] != 1 {
+			t.Errorf("%s was watched %d times, want once", state, watches[state])
+		}
+	}
+	// ADR 0580 clause 3: the compare reads through mesh-sdk's watched reader and the seat keeps no mirror of its own.
+	for f := range reflect.TypeFor[wantsTools]().Fields() {
+		if f.Type.Kind() == reflect.Map || (f.Type.Kind() == reflect.Pointer && f.Type.Elem().Kind() == reflect.Map) {
+			t.Errorf("wantsTools keeps %s, a copy of its own beside the watched reader", f.Name)
+		}
+	}
+	if watches[policiesState] != 0 {
+		t.Errorf("the seat's own small policies state was watched: %v", watches)
+	}
+	// a person's record for web: written, recorded, said.
+	if _, err := w.doUpgrade(map[string]any{"module": "web", "policy": "record", "why": "the operator checks it"}, "person.jochen"); err != nil {
+		t.Fatal(err)
+	}
+	chosen, _ := assign.DecodePolicies(st[policiesState].values)
+	if c := chosen["web"]; c.Policy != catalogue.PolicyRecord || c.By != "person.jochen" || !slices.Contains(asked, "seat:mesh-hand-acts.hand-act") ||
+		len(said) != 1 || !strings.HasPrefix(said[0], "policy-changed policy-changed.web.") {
+		t.Errorf("chosen %+v, asked %v, said %v", c, asked, said)
+	}
+	// A person may choose the bus's policy as any module's (ADR 0601 §1: no part treats the module that provides the bus apart).
+	if _, err := w.doUpgrade(map[string]any{"module": "nats", "policy": "roll", "why": "x"}, "op"); err != nil {
+		t.Errorf("a person's policy for the bus was refused: %v", err)
+	}
+	if _, err := w.doUpgrade(map[string]any{"module": "nats", "policy": "default", "why": "back to the module"}, "op"); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := w.doUpgrade(map[string]any{"module": "web", "policy": "roll"}, "op"); err == nil {
+		t.Error("a policy without why was set")
+	}
+	if _, err := w.doUpgrade(map[string]any{"module": "web", "policy": "default", "why": "back to the module"}, "op"); err != nil || len(st[policiesState].values) != 0 {
+		t.Errorf("default left %v (%v)", st[policiesState].values, err)
+	}
+	// bus: the node behind the indexer's newest.
+	b, err := w.doBus(nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	nodes := b.(map[string]any)["nodes"].([]busNode)
+	if b.(map[string]any)["module"] != "nats" || len(nodes) != 2 || !nodes[0].Behind || nodes[1].Behind || !slices.Contains(asked, "seat:mesh-hand-acts.hand-acts") {
+		t.Errorf("bus = %+v, asked %v", b, asked)
+	}
+	if tools := w.tools(); len(tools) != 2 || tools[0].Name != "mesh-wants.upgrade" || tools[1].Run == nil {
 		t.Errorf("the seat's verbs as served: %+v", tools)
 	}
 }
@@ -153,5 +505,69 @@ func readManifest() (catalogue.Manifest, error) {
 	if err != nil {
 		return catalogue.Manifest{}, err
 	}
-	return catalogue.ParseManifest(raw)
+	return catalogue.Decode(raw)
+}
+
+// countingKV is a memKV that counts its puts.
+type countingKV struct {
+	memKV
+	writes *int
+}
+
+func (c *countingKV) Put(ctx context.Context, key string, value []byte) (uint64, error) {
+	*c.writes++
+	return c.memKV.Put(ctx, key, value)
+}
+
+// revKV is a bucket with real revisions, refusing a write at a revision that is not the key's, and a write of refuse;
+// log is every write in order.
+type revKV struct {
+	jetstream.KeyValue
+	rev    uint64
+	values map[string][]byte
+	revs   map[string]uint64
+	log    []string
+	refuse string
+}
+
+func (k *revKV) write(key string, value []byte) uint64 {
+	k.rev++
+	k.values[key], k.revs[key] = value, k.rev
+	return k.rev
+}
+
+func (k *revKV) Create(_ context.Context, key string, value []byte, _ ...jetstream.KVCreateOpt) (uint64, error) {
+	if _, ok := k.values[key]; ok || key == k.refuse {
+		return 0, errors.New("key exists")
+	}
+	k.log = append(k.log, "create "+key)
+	return k.write(key, value), nil
+}
+
+func (k *revKV) Update(_ context.Context, key string, value []byte, revision uint64) (uint64, error) {
+	if k.revs[key] != revision || key == k.refuse {
+		return 0, errors.New("wrong last sequence")
+	}
+	k.log = append(k.log, "update "+key)
+	return k.write(key, value), nil
+}
+
+func (k *revKV) Delete(_ context.Context, key string, _ ...jetstream.KVDeleteOpt) error {
+	if key == k.refuse {
+		return errors.New("wrong last sequence")
+	}
+	k.log = append(k.log, "delete "+key)
+	delete(k.values, key)
+	delete(k.revs, key)
+	return nil
+}
+
+// historyStore is a memStore whose history is given.
+type historyStore struct {
+	memStore
+	revisions map[string][]stdio.StateRevision
+}
+
+func (s historyStore) history(_, key string) ([]stdio.StateRevision, error) {
+	return s.revisions[key], nil
 }

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/tools.go

@@ -14,6 +14,8 @@ import (
 
 	stdio "git.novox.be/novox/mesh-sdk/go"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
+
+	"git.novox.be/novox/mesh-delivery/sdk/enginereads"
 )
 
 // The assigner's tools (novox/hq ADR 0546), served through the tool runner from its bundle: a process never serves (ADR
@@ -21,6 +23,9 @@ import (
 // every step as the event put. They are the module's own tools; the seat mesh-placement's verbs are served beside them
 // (seat_tools.go, ADR 0567 §10).
 
+// engineReadsTool lists what each node's engine reads, as the assigner uses it, and asks one node's engine again.
+const engineReadsTool = "assigner_engine_reads"
+
 // putsState is the assigner's state of puts, as the runtime names a module's own state.
 const putsState = "puts"
 
@@ -351,7 +356,17 @@ func serveTools() error {
 			time.Sleep(wait)
 		}
 	}()
-	return stdio.Serve("", append(s.tools(), newSeatTools(runtimeStore{}, stdio.Ask).tools()...))
+	tools := append(s.tools(), newSeatTools(runtimeStore{}, stdio.Ask).tools()...)
+	wants := newWantsTools(runtimeStore{}, stdio.Ask, func(e, id string, b any) error {
+		// The seat's event, said on the seat: a claimed seat's event is never the module's own.
+		return stdio.SeatPublish(wantsEventSubject(e), b, id)
+	})
+	wants.watched = stdio.NewWatchedStates() // the large states read whole from one watched copy (ADR 0580 clause 3)
+	tools = append(tools, wants.tools()...)
+	tools = append(tools, viewTools(os.Getenv, keptSource, time.Now)...)
+	// What each node's engine reads, as the assigner uses it (ADR 0618 §3): its own state engine-reads, asked again through it.
+	tools = append(tools, enginereads.Tool(engineReadsTool, "the assigner", enginereads.KeptState(stdio.State(engineReadsState)), false, time.Now))
+	return stdio.Serve("", tools)
 }
 
 // shortFP is a fingerprint's first twelve hex digits.

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/verbs.go

@@ -0,0 +1,128 @@
+package main
+
+import (
+	"context"
+	"slices"
+
+	"git.novox.be/novox/mesh-sdk/go/catalogue"
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+
+	"git.novox.be/novox/mesh-delivery/sdk/graph"
+
+	"mesh-delivery-assigner/internal/assign"
+)
+
+// The verb edges a want waits on (novox/hq ADR 0614 §2, §3): the module graph the indexer writes names what each module
+// invokes and serves and which of its verb edges it leaves out on a cycle (one place decides the cycle); a want waits for
+// each kept edge until a build serving its verb runs healthy, read from the haves, the builder's builds and the indexer's
+// manifests, as a provider is counted (ADR 0603 §5).
+
+// moduleGraph is the module graph as the indexer's first view and views family last said it (ADR 0631); a key that
+// does not decode is left out, so its module waits on no verb.
+func (p *passer) moduleGraph() graph.Graph {
+	g := graph.Graph{}
+	for key, raw := range p.w.read(graph.Bucket) {
+		module, err := graph.ParseKey(key)
+		if err != nil {
+			continue
+		}
+		if n, err := graph.Decode(raw); err == nil {
+			g[module] = n
+		}
+	}
+	return g
+}
+
+// keptInvokes are the verbs of module the graph keeps as edges: each it invokes and does not leave out, that a module
+// other than itself serves. A verb no module of the graph serves is no edge, so it holds nothing; nil when the graph holds
+// no node of module.
+func keptInvokes(g graph.Graph, module string) []string {
+	n, ok := g[module]
+	if !ok {
+		return nil
+	}
+	var out []string
+	for _, v := range n.Invokes {
+		if slices.Contains(n.LeftOut, v) {
+			continue
+		}
+		if slices.ContainsFunc(g.Servers(v), func(s string) bool { return s != module }) {
+			out = append(out, v)
+		}
+	}
+	return out
+}
+
+// served is, for this pass, whether a build serving a verb runs healthy on some node (graph.Served): every running healthy
+// have's build (the builder's builds key of its module and fingerprint) names its manifest, and the verbs that manifest
+// serves are served. A healthy build whose manifest cannot be read counts what the graph says its module serves, said in
+// the log, so a build read late never holds its callers for good; nil when the graph holds nothing, and no want waits on
+// a verb.
+func (p *passer) served(ctx context.Context, get getter, g graph.Graph, n assign.Nodes) func(string) bool {
+	if len(g) == 0 {
+		return nil
+	}
+	served, unread := graph.Served(n.Haves, func(module, fp string) ([]string, bool) { return p.servesOf(ctx, get, module, fp) },
+		func(module string) []string { return g[module].Serves })
+	if len(unread) > 0 {
+		p.logf("the manifest of the running build of %v cannot be read, so what the module graph says they serve is counted as served", unread)
+	}
+	return served
+}
+
+// offering is, for this pass, whether a build whose manifest offers a provision runs healthy on a node present (ADR 0603
+// §5, ADR 0614 §5): every running healthy have on an online node, its build's manifest read as servesOf reads it. A
+// healthy build whose manifest cannot be read counts what its module's trunk manifest offers, so a build read late never
+// holds a consumer for good.
+func (p *passer) offering(ctx context.Context, get getter, trunk map[string]catalogue.Manifest, n assign.Nodes) func(string) bool {
+	offered := map[string]bool{}
+	for node, haves := range n.Haves {
+		if !n.Online[node] {
+			continue
+		}
+		for module, h := range haves {
+			if h.Phase != delivery.PhaseRunning || h.Health != delivery.HealthOK {
+				continue
+			}
+			m, ok := p.manifestOf(ctx, get, module, h.FP)
+			if !ok {
+				m = trunk[module]
+			}
+			for _, o := range m.Offers() {
+				offered[o] = true
+			}
+		}
+	}
+	return func(provision string) bool { return offered[provision] }
+}
+
+// servesOf are the verbs the manifest of module's build at fp serves (graph.ServesOf), and whether it could be read.
+func (p *passer) servesOf(ctx context.Context, get getter, module, fp string) ([]string, bool) {
+	m, ok := p.manifestOf(ctx, get, module, fp)
+	if !ok {
+		return nil, false
+	}
+	return graph.ServesOf(m), true
+}
+
+// manifestOf is the manifest of module's build at fp (the builder's build names its digest in the indexer's manifests),
+// and whether it could be read.
+func (p *passer) manifestOf(ctx context.Context, get getter, module, fp string) (catalogue.Manifest, bool) {
+	key, err := delivery.BuilderBuildKey(module, fp)
+	if err != nil {
+		return catalogue.Manifest{}, false
+	}
+	raw := p.w.value(delivery.BuilderBuildsBucket, key)
+	if raw == nil {
+		return catalogue.Manifest{}, false
+	}
+	b, err := delivery.DecodeBuilderBuild(raw)
+	if err != nil || b.Manifest == "" {
+		return catalogue.Manifest{}, false
+	}
+	got := p.w.manifest(ctx, get, b.Manifest)
+	if got.err != "" {
+		return catalogue.Manifest{}, false
+	}
+	return got.manifest, true
+}

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/views.go

@@ -0,0 +1,235 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"slices"
+	"time"
+
+	"github.com/nats-io/nats.go/jetstream"
+
+	stdio "git.novox.be/novox/mesh-sdk/go"
+	"git.novox.be/novox/mesh-sdk/go/catalogue"
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/handacts"
+	"git.novox.be/novox/mesh-sdk/go/health"
+	"git.novox.be/novox/mesh-sdk/go/process"
+
+	"git.novox.be/novox/mesh-sdk/go/views"
+
+	"git.novox.be/novox/mesh-delivery/sdk/graph"
+	"git.novox.be/novox/mesh-delivery/sdk/heard"
+
+	"mesh-delivery-assigner/internal/assign"
+)
+
+// viewsStream is the assigner's views family on its old streams section, beside placement (ADR 0619 §2, ADR 0615 §5),
+// as its manifest's `streams` names it; indexerViewsStream is the indexer's, as the indexer's manifest names it.
+const (
+	viewsStream        = "assigner-views"
+	indexerViewsStream = "indexer-views"
+)
+
+// marksBucket is the assigner's state of what its views family said each state up to.
+var marksBucket = delivery.AssignerModule + "_" + views.MarksState
+
+// viewedTool is one tool over one state of the assigner's.
+type viewedTool struct{ tool, state, words string }
+
+// firstViewTools are the assigner's first-view tools (ADR 0621 §1): each answers only its callers list
+// (views.CallersEnv), which the manifest writes.
+var firstViewTools = []viewedTool{
+	{"placement", delivery.PlacementState, "where each module is placed: the seat mesh-placement's placement, by module."},
+	{"seat-holders", delivery.SeatHoldersState, "who holds which seat on which node."},
+	{"wants", "wants", "what each node should run: want.<node>.<module>, its fingerprint and the rule that gave it."},
+}
+
+// readTools are the assigner's ordinary read tools, one per state its readers read (design 25 § 12.2).
+var readTools = []viewedTool{
+	{"assigner_read_placement", delivery.PlacementState, "where each module is placed, by module."},
+	{"assigner_read_seat_holders", delivery.SeatHoldersState, "who holds which seat on which node."},
+	{"assigner_read_wants", "wants", "what each node should run: want.<node>.<module>."},
+	{"assigner_read_findings", health.FindingsState, "the assigner's findings, which the condition keeper raises and clears."},
+	{"assigner_read_asks", "asks", "the asks the assigner put to a person, and their answers."},
+	{"assigner_read_differences", "differences", "every difference between a want and what a node runs."},
+}
+
+// viewedStates are the states the views family says, each by its bucket: the six its readers read.
+var viewedStates = map[string]string{
+	delivery.PlacementState:   delivery.PlacementBucket,
+	delivery.SeatHoldersState: delivery.SeatHoldersBucket,
+	"wants":                   delivery.AssignerWantsBucket,
+	health.FindingsState:      assign.FindingsBucket,
+	"asks":                    delivery.AssignerAsksBucket,
+	"differences":             delivery.AssignerDifferencesBucket,
+}
+
+// viewTools are the assigner's first-view and read tools, reading only its own states, so they answer as soon as its
+// runtime of its own is connected (ADR 0621 §3).
+func viewTools(getenv func(string) string, state func(string) views.Source, now func() time.Time) []stdio.Tool {
+	marks := state(views.MarksState)
+	var out []stdio.Tool
+	for _, t := range firstViewTools {
+		out = append(out, views.FirstViewTool(delivery.AssignerModule, t.tool, t.state, t.words, views.ParseCallers(getenv(views.CallersEnv(t.tool))), state(t.state), marks, now))
+	}
+	for _, t := range readTools {
+		out = append(out, views.ReadTool(delivery.AssignerModule, t.tool, t.state, t.words, state(t.state), marks, now))
+	}
+	// Its own first views, of the indexer's manifests, modules and graph (DLV-F3r, ADR 0631 §2): read, and asked again by hand.
+	return append(out, views.StatusTools(delivery.AssignerModule, "assigner_first_views", "assigner_first_view_again", stdio.State(views.StatusState), handacts.Recorder{Ask: stdio.Ask}, now)...)
+}
+
+func keptSource(name string) views.Source { return views.KeptSource{State: stdio.State(name)} }
+
+// startViews says each change of the assigner's viewed states on its views family, once its marks state is bound,
+// each state as soon as its bucket is (kvs, or bound once it appears). A watch that ends is sent on errs.
+func startViews(ctx context.Context, js jetstream.JetStream, nc process.Subscriber, account process.Account, kvs buckets, findings assign.Findings, errs chan<- error, logf func(string, ...any)) {
+	tooLarge := func(state, key string, size int) {
+		if findings.Put == nil {
+			return
+		}
+		k, v, err := views.TooLargeFinding(delivery.AssignerModule, state, key, size, time.Now())
+		if err == nil {
+			err = findings.Put(k, v)
+		}
+		if err != nil {
+			logf("views: the finding of %s.%s too large is not written: %v", state, key, err)
+		}
+	}
+	process.AwaitBucket(ctx, js, nc, marksBucket, "no change is said on the views family, so every reader waits on its first view", logf).Ready(func(mk jetstream.KeyValue) {
+		em := viewsEmitter(js, account, mk, findings, tooLarge, logf)
+		for _, state := range []string{"asks", "differences", health.FindingsState, delivery.PlacementState, delivery.SeatHoldersState, "wants"} {
+			state := state
+			start := func(kv jetstream.KeyValue) {
+				if err := em.Start(ctx, state, kv, errs); err != nil {
+					logf("%v: its readers ask its first view at each change until the assigner starts again", err)
+				}
+			}
+			if kv := kvs[viewedStates[state]]; kv != nil {
+				start(kv)
+				continue
+			}
+			process.AwaitBucket(ctx, js, nc, viewedStates[state], "its changes are not said on the views family", logf).Ready(start)
+		}
+	})
+}
+
+// viewsEmitter is the assigner's emitter of its views family: a change not said past views.Bound is its finding
+// view-unsaid, in its findings (review round 2); with no findings state it is said in the log only.
+func viewsEmitter(js jetstream.JetStream, account process.Account, mk jetstream.KeyValue, findings assign.Findings, tooLarge func(string, string, int), logf func(string, ...any)) views.Emitter {
+	em := views.Emitter{Owner: delivery.AssignerModule, Subject: account.StreamSubject, Publish: views.JetStreamPublish(js), Marks: mk, TooLarge: tooLarge, Logf: logf}
+	if findings.Put != nil && findings.Delete != nil {
+		em.Findings = assignerFindings{findings}
+	}
+	return em
+}
+
+// assignerFindings is the assigner's findings as views.Emitter's Findings.
+type assignerFindings struct{ f assign.Findings }
+
+func (a assignerFindings) Put(key string, value []byte) error { return a.f.Put(key, value) }
+func (a assignerFindings) Delete(key string) error            { return a.f.Delete(key) }
+
+// firstViewsBucket is the assigner's own state of its first views (views.StatusState).
+var firstViewsBucket = delivery.AssignerModule + "_" + views.StatusState
+
+// indexerViews are the assigner's first views of the indexer's manifests, modules and module graph (ADR 0615 §1,
+// ADR 0621 §2, ADR 0631; DLV-F2r): asked at the start through the indexer's tools, then followed on indexer-views, asking once more on a gap;
+// past the bound its finding names the indexer and the tool, cleared by the answer.
+type indexerViews struct {
+	js       jetstream.JetStream
+	account  process.Account
+	call     func(string, any) (json.RawMessage, error)
+	findings assign.Findings
+	status   *process.AwaitedBucket
+	logf     func(string, ...any)
+}
+
+// indexerFirstViews are the indexer's states the assigner takes by first view and the views family, each by the name of
+// the indexer's bucket the world keeps it under: manifests and modules (ADR 0621 §2), and the module graph, whose verb
+// edges a want waits on (ADR 0614 §2, §3; ADR 0631 §1).
+var indexerFirstViews = map[string]string{"manifests": delivery.ManifestsBucket, "modules": delivery.ModulesBucket, graph.State: graph.Bucket}
+
+// firstViewBound and firstViewWait are each first view's bound before its condition is raised, and its first wait
+// between two failed asks; zero is the views package's (views.Bound, two minutes, ADR 0615 §6; and a first wait of five
+// seconds). A test shortens them.
+var firstViewBound, firstViewWait time.Duration
+
+// start asks the three first views, each answer taken into w under the indexer's bucket names and settled once (a pass waits
+// for it), and hears the views family; it answers how many settles to wait for.
+func (iv *indexerViews) start(ctx context.Context, w *world, wake func(), settled chan<- struct{}) int {
+	finding := func(s views.Status, raised bool) {
+		if iv.findings.Put == nil {
+			return
+		}
+		key, value, err := views.UnansweredFinding(delivery.AssignerModule, s, time.Now())
+		if err == nil && raised {
+			err = iv.findings.Put(key, value)
+		} else if err == nil {
+			err = iv.findings.Delete(key)
+		}
+		if err != nil {
+			iv.logf("views: the finding of the first view %s is not written: %v", s.Tool, err)
+		}
+	}
+	followers := map[string]*views.Follower{}
+	var all []*views.Follower
+	for state, bucket := range indexerFirstViews {
+		bucket := bucket
+		tool := delivery.IndexerModule + "." + state
+		f := &views.Follower{Owner: delivery.IndexerModule, Tool: tool, State: state, Ask: views.AskVia(iv.call, tool), Logf: iv.logf,
+			Bound: firstViewBound, Wait: firstViewWait,
+			Raise: func(s views.Status) { finding(s, true) }, Clear: func(s views.Status) { finding(s, false) },
+			Changed: func(key string, value json.RawMessage, deleted bool, at time.Time) {
+				if deleted {
+					value = nil
+				}
+				w.putEntry(bucket, key, value, 0, at)
+				wake()
+			}}
+		followers[state] = f
+		all = append(all, f)
+		go func() {
+			if f.Start(ctx) == nil {
+				settled <- struct{}{}
+			}
+		}()
+	}
+	if iv.status != nil {
+		iv.status.Ready(func(kv jetstream.KeyValue) {
+			for _, f := range all {
+				f.Said = views.KeepStatus(ctx, kv, iv.logf)
+			}
+			if err := views.HearAgain(ctx, kv, all, iv.logf); err != nil {
+				iv.logf("views: assigner_first_view_again is not heard (%v) until the assigner starts again", err)
+			}
+		})
+	}
+	// Not heard, the indexer's views family is the finding family-not-heard until it binds (ADR 0615 §5).
+	stream := catalogue.StreamBusName(indexerViewsStream)
+	_ = notHeardWriter(iv.findings, iv.logf).Bind(stream, "the indexer's manifests, modules and graph are the first views' alone until the assigner starts again", func() error {
+		cons, err := iv.account.EventConsumer(ctx, iv.js, stream)
+		if err != nil {
+			return fmt.Errorf("the consumer %s on %s does not exist yet: %w", iv.account.EventConsumerName(), stream, err)
+		}
+		_, err = process.HearEvents(cons, views.Hear(ctx, followers, iv.logf), iv.logf)
+		return err
+	})
+	return len(all)
+}
+
+// notHeardWriter writes the assigner's finding of a family it does not hear into its findings (heard.Writer); with no
+// findings state it is said in the log alone.
+func notHeardWriter(findings assign.Findings, logf func(string, ...any)) heard.Writer {
+	w := heard.Writer{Observer: delivery.AssignerModule, Logf: logf, Put: findings.Put}
+	if findings.Delete != nil {
+		w.Delete = func(key string) error {
+			if keys, err := findings.Keys(); err == nil && !slices.Contains(keys, key) {
+				return nil // none stands
+			}
+			return findings.Delete(key)
+		}
+	}
+	return w
+}

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/wants_tools.go

@@ -0,0 +1,320 @@
+package main
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"sort"
+	"strconv"
+	"time"
+
+	stdio "git.novox.be/novox/mesh-sdk/go"
+	"git.novox.be/novox/mesh-sdk/go/catalogue"
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/handacts"
+	"git.novox.be/novox/mesh-sdk/go/health"
+
+	"mesh-delivery-assigner/internal/assign"
+)
+
+// The seat mesh-wants' verbs (novox/hq ADR 0565 §7, §8, §9, §15; issue 1953 D4-D6), served through the tool runner beside the
+// put tools and mesh-placement's verbs. `upgrade` reads and sets a person's upgrade policy, kept in the state `policies`
+// (each set recorded as a hand act and said as policy-changed), and with compare lists the digest of the composition each node's
+// own have names beside every composition each node published (ADR 0593 §8, composed.go); `bus` says what a bus upgrade would do. The assigner's process reads
+// `policies` when it judges a move and writes the finding policy-split while a split stands.
+
+// The states the verbs read, as the runtime names them.
+const (
+	policiesState  = delivery.AssignerPoliciesState
+	manifestsState = delivery.IndexerModule + ".manifests"
+	// PolicyChangedEvent is the seat's event of a person's policy set or taken back.
+	PolicyChangedEvent = "policy-changed"
+	// busStepCause is the cause the bus's step is recorded under in the hand-act log.
+	busStepCause = "bus-upgrade"
+)
+
+// wantsTools serves the seat's verbs over a store, asking seats through ask and saying events through emit.
+type wantsTools struct {
+	st   seatStore
+	ask  func(key string, body any) (json.RawMessage, error)
+	emit func(event, id string, body any) error
+	now  func() time.Time
+	// watched is the copy of the large states it reads whole, each by one watch started on its first read and kept by
+	// its changes after (mesh-sdk's WatchedStates, novox/hq ADR 0580 clause 3), never a get per key, which timed out on
+	// a large state (issue 1953 L5f). Nil reads key by key.
+	watched *stdio.WatchedStates
+}
+
+// wantsEventSubject is the subject of one of the seat's events.
+func wantsEventSubject(event string) string {
+	return "mesh.seat." + catalogue.WantsSeat + ".event." + event
+}
+
+func newWantsTools(st seatStore, ask func(string, any) (json.RawMessage, error), emit func(event, id string, body any) error) *wantsTools {
+	return &wantsTools{st: st, ask: ask, emit: emit, now: time.Now}
+}
+
+// values reads every key of a state: from the watched copy when there is one, else key by key.
+func (s *wantsTools) values(state string) (map[string][]byte, error) {
+	if s.watched != nil {
+		return s.watched.Values(state)
+	}
+	return s.direct(state)
+}
+
+// direct reads a state key by key, for a small state of the seat's own.
+func (s *wantsTools) direct(state string) (map[string][]byte, error) {
+	keys, err := s.st.keys(state)
+	if err != nil {
+		return nil, fmt.Errorf("%s cannot be listed: %w", state, err)
+	}
+	out := map[string][]byte{}
+	for _, k := range keys {
+		raw, _, found, err := s.st.get(state, k)
+		if err != nil {
+			return nil, fmt.Errorf("%s %s cannot be read: %w", state, k, err)
+		}
+		if found {
+			out[k] = raw
+		}
+	}
+	return out, nil
+}
+
+// manifest reads a manifest by its digest: kept once read when there is a watched copy, a manifest never changing
+// under its digest.
+func (s *wantsTools) manifest(digest string) ([]byte, bool, error) {
+	if s.watched != nil {
+		return s.watched.Once(manifestsState, digest)
+	}
+	raw, _, found, err := s.st.get(manifestsState, digest)
+	return raw, found, err
+}
+
+// manifests is every module the indexer holds, with its trunk manifest and fingerprint.
+func (s *wantsTools) manifests() (map[string]catalogue.Manifest, map[string]delivery.Module, error) {
+	mods, err := s.values(modulesState)
+	if err != nil {
+		return nil, nil, err
+	}
+	out, held := map[string]catalogue.Manifest{}, map[string]delivery.Module{}
+	for name, raw := range mods {
+		m, err := delivery.DecodeModule(raw)
+		if err != nil {
+			continue
+		}
+		held[name] = m
+		if m.Manifest == "" {
+			continue
+		}
+		mraw, found, err := s.manifest(m.Manifest)
+		if err != nil || !found {
+			continue
+		}
+		kept, err := delivery.DecodeManifest(mraw)
+		if err != nil {
+			continue
+		}
+		// Decoded, never judged (ADR 0578 §3); one that does not decode is left out of the answer, as before.
+		if man, err := catalogue.Decode([]byte(kept.JSON)); err == nil {
+			out[name] = man
+		}
+	}
+	return out, held, nil
+}
+
+// policyRow is one module's policy as upgrade answers it.
+type policyRow struct {
+	Module string `json:"module"`
+	Policy string `json:"policy"`
+	From   string `json:"from"`
+	Why    string `json:"why,omitempty"`
+	By     string `json:"by,omitempty"`
+}
+
+// doUpgrade is the verb upgrade: read every module's policy or one's; with policy and why set a person's choice, or take it
+// back with default; with compare each node's composition and the assigner's findings.
+func (s *wantsTools) doUpgrade(args map[string]any, by string) (any, error) {
+	manifests, _, err := s.manifests()
+	if err != nil {
+		return nil, err
+	}
+	raw, err := s.direct(policiesState) // the seat's own small state, read whole after its own writes
+	if err != nil {
+		return nil, err
+	}
+	chosen, unreadable := assign.DecodePolicies(raw)
+	if arg(args, "compare") == "true" {
+		haves, err := s.values(haveState)
+		if err != nil {
+			return nil, err
+		}
+		composed := map[string]string{}
+		for key, raw := range haves {
+			if node, _, isNode, err := delivery.ParseHaveKey(key); err == nil && isNode {
+				if h, err := delivery.DecodeHaveNode(raw); err == nil && h.Composed != "" {
+					composed[node] = h.Composed
+				}
+			}
+		}
+		out := map[string]any{"composed": composed}
+		// And what every node published (ADR 0593 §8), read only to compare.
+		if values, err := s.values(delivery.ComposedRead); err != nil {
+			out["published-unread"] = err.Error()
+		} else {
+			out["published"] = published(values)
+		}
+		// The assigner's findings, its said conditions as the condition keeper reads them (§15).
+		if found, err := s.values(health.FindingsState); err != nil {
+			out["findings-unread"] = err.Error()
+		} else {
+			keys := []string{}
+			for k := range found {
+				keys = append(keys, k)
+			}
+			sort.Strings(keys)
+			out["findings"] = keys
+		}
+		return out, nil
+	}
+	module, policy := arg(args, "module"), arg(args, "policy")
+	if policy != "" {
+		return s.setPolicy(module, policy, arg(args, "why"), by, manifests)
+	}
+	var rows []policyRow
+	for name, m := range manifests {
+		if module != "" && name != module {
+			continue
+		}
+		p, from, why, who := assign.PolicyOf(m, chosen)
+		rows = append(rows, policyRow{Module: name, Policy: p, From: from, Why: why, By: who})
+	}
+	if module != "" && len(rows) == 0 {
+		return nil, fmt.Errorf("the indexer holds no manifest of %s", module)
+	}
+	sort.Slice(rows, func(i, j int) bool { return rows[i].Module < rows[j].Module })
+	return map[string]any{"modules": rows, "unreadable": unreadable}, nil
+}
+
+// setPolicy writes a person's choice of a module's policy, or deletes it for default, records the act in the hand-act log
+// and says policy-changed. The bus's choice is a person's as any module's (ADR 0601 §1).
+func (s *wantsTools) setPolicy(module, policy, why, by string, manifests map[string]catalogue.Manifest) (any, error) {
+	if module == "" {
+		return nil, errors.New("a policy is set for one module: name it")
+	}
+	if _, ok := manifests[module]; !ok {
+		return nil, fmt.Errorf("the indexer holds no manifest of %s", module)
+	}
+	if why == "" {
+		return nil, errors.New("a person's policy says why")
+	}
+	if by == "" || by == stdio.Unproven {
+		return nil, errors.New("a person's policy names who chose it, and the runtime proved no caller")
+	}
+	what := fmt.Sprintf("mesh-wants.upgrade %s %s", module, policy)
+	if policy == "default" {
+		if err := s.st.del(policiesState, module); err != nil {
+			return nil, fmt.Errorf("the choice for %s cannot be taken back: %w", module, err)
+		}
+	} else {
+		p := catalogue.PersonPolicy{V: catalogue.PersonPolicyVersion, Module: module, Policy: policy, Why: why, By: by, At: s.now().UTC()}
+		if err := p.Check(); err != nil {
+			return nil, err
+		}
+		raw, _ := json.Marshal(p)
+		if err := s.st.put(policiesState, module, raw); err != nil {
+			return nil, fmt.Errorf("the choice for %s cannot be written: %w", module, err)
+		}
+	}
+	rec := handacts.Recorder{Ask: s.ask}
+	taken, rerr := rec.Record(handacts.Request{What: what, Why: why, Cause: "upgrade-policy", Verb: "mesh-wants.upgrade"})
+	recorded := taken.Log
+	if rerr != nil {
+		recorded = "not recorded: " + rerr.Error()
+	}
+	body := map[string]any{"module": module, "policy": policy, "why": why, "by": by}
+	said := ""
+	if s.emit != nil {
+		id := PolicyChangedEvent + "." + module + "." + strconv.FormatInt(s.now().UnixNano(), 10)
+		if err := s.emit(PolicyChangedEvent, id, body); err != nil {
+			said = "not said: " + err.Error()
+		}
+	}
+	return map[string]any{"set": body, "hand-act": recorded, "event": said}, nil
+}
+
+// busNode is one node's bus as bus answers it.
+type busNode struct {
+	Node   string `json:"node"`
+	FP     string `json:"fp"`
+	Behind bool   `json:"behind"`
+}
+
+// doBus is the verb bus: the fingerprint of the bus module each node runs against the indexer's newest, the nodes behind,
+// the last bus steps of the hand-act log and the assigner's puts of the bus. Read-only.
+func (s *wantsTools) doBus(map[string]any) (any, error) {
+	manifests, held, err := s.manifests()
+	if err != nil {
+		return nil, err
+	}
+	bus := ""
+	for name, m := range manifests {
+		if catalogue.ProvidesBus(m) {
+			bus = name
+		}
+	}
+	if bus == "" {
+		return nil, errors.New("the indexer holds no module that provides the bus")
+	}
+	newest := held[bus].FP2
+	haves, err := s.values(haveState)
+	if err != nil {
+		return nil, err
+	}
+	var nodes []busNode
+	for key, raw := range haves {
+		node, module, isNode, err := delivery.ParseHaveKey(key)
+		if err != nil || isNode || module != bus {
+			continue
+		}
+		h, err := delivery.DecodeHave(raw)
+		if err != nil || h.Phase == delivery.PhaseRemoved {
+			continue
+		}
+		nodes = append(nodes, busNode{Node: node, FP: h.FP, Behind: newest != "" && h.FP != newest})
+	}
+	sort.Slice(nodes, func(i, j int) bool { return nodes[i].Node < nodes[j].Node })
+	out := map[string]any{"module": bus, "newest": newest, "nodes": nodes}
+	if steps, err := s.ask("seat:"+handacts.Seat+".hand-acts", map[string]any{"cause": busStepCause, "days": 90}); err != nil {
+		out["steps-unread"] = err.Error()
+	} else {
+		out["steps"] = steps
+	}
+	puts, err := s.values(putsState)
+	if err != nil {
+		out["puts-unread"] = err.Error()
+	} else {
+		mine := map[string]json.RawMessage{}
+		for k, v := range puts {
+			if _, module, err := delivery.ParsePutKey(k); err == nil && module == bus {
+				mine[k] = v
+			}
+		}
+		out["puts"] = mine
+	}
+	return out, nil
+}
+
+// tools are the seat's verbs as the runtime serves them, each named <seat>.<verb>, with the seat's own schemas.
+func (s *wantsTools) tools() []stdio.Tool {
+	seat, _ := catalogue.SeatNamed(catalogue.WantsSeat)
+	run := map[string]func(map[string]any) (any, error){
+		"upgrade": func(a map[string]any) (any, error) { return s.doUpgrade(a, stdio.CallerOf(a)) },
+		"bus":     s.doBus,
+	}
+	var out []stdio.Tool
+	for _, v := range seat.Serves {
+		out = append(out, stdio.Tool{Name: catalogue.WantsSeat + "." + v.Name, Description: v.Description, Input: v.Input, Run: run[v.Name]})
+	}
+	return out
+}

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/world.go

@@ -2,23 +2,17 @@ package main
 
 import (
 	"context"
-	"encoding/json"
 	"errors"
-	"fmt"
+	"maps"
 	"slices"
 	"sort"
-	"strings"
 	"sync"
 	"time"
 
 	"github.com/nats-io/nats.go/jetstream"
 
-	"git.novox.be/novox/mesh-sdk/go/buscompose"
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
-	"git.novox.be/novox/mesh-sdk/go/compose"
-	"git.novox.be/novox/mesh-sdk/go/compose/frombus"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/provider"
 
 	"mesh-delivery-assigner/internal/assign"
 )
@@ -27,18 +21,6 @@ import (
 // for (mesh-sdk delivery.CandidateNoneNoModule, which the indexer writes): the change removes the module.
 const noModuleWords = delivery.CandidateNoneNoModule
 
-// assignment holds only the fields of the controller's Assignment the assigner reads (the view's own, mesh-delivery-view
-// internal/view/view.go): an assignment stands while it has not ended and has no state.
-type assignment struct {
-	Node   string    `json:"node"`
-	Module string    `json:"module"`
-	Build  string    `json:"build"`
-	Ended  time.Time `json:"ended"`
-	State  string    `json:"state"`
-}
-
-func (a assignment) open() bool { return a.Ended.IsZero() && a.State == "" }
-
 // world is what the assigner watched, as it stands now: every value by bucket and key, and the manifests read by
 // digest. The watches write it; a pass reads it.
 type world struct {
@@ -51,6 +33,14 @@ type world struct {
 	changes map[string]uint64
 	// meta is, by bucket and key, the revision and the time of the value held now, where the watch said them (putEntry).
 	meta map[string]entryMeta
+	// trunkBuilt is, by module, its newest done trunk build in the builder's log (putBuilt).
+	trunkBuilt map[string]delivery.BuildLogEntry
+	// placement is the seat's state placement assembled node by node from its keys in either form (mesh-sdk
+	// delivery.PlacementKeys; research 072 row 37): the one reader of its keys in the assigner.
+	placement *delivery.PlacementKeys
+	// sourceGroups is, by revision of the gate's source.main, the release (group) that moved it, from every revision its
+	// history keeps (watched with history): a build's source revision names the release that carries it (ADR 0601 §1).
+	sourceGroups map[uint64]string
 }
 
 // entryMeta is a value's revision in its bucket and when it was written.
@@ -68,7 +58,8 @@ type parsed struct {
 
 func newWorld() *world {
 	return &world{values: map[string]map[string][]byte{}, manifests: map[string]parsed{}, healthy: map[string][]string{}, changes: map[string]uint64{},
-		meta: map[string]entryMeta{}}
+		meta: map[string]entryMeta{}, trunkBuilt: map[string]delivery.BuildLogEntry{}, placement: delivery.NewPlacementKeys(),
+		sourceGroups: map[uint64]string{}}
 }
 
 // putEntry is put, keeping the value's revision and the time it was written.
@@ -81,6 +72,47 @@ func (w *world) putEntry(bucket, key string, value []byte, revision uint64, at t
 		return
 	}
 	w.meta[bucket+"|"+key] = entryMeta{revision: revision, at: at}
+	if bucket == delivery.PlacementBucket {
+		_, _ = w.placement.Put(key, value, revision, false) // put took it already; this is its revision
+	}
+	if bucket == delivery.SourceBucket && key == delivery.SourceMainKey {
+		if s, err := delivery.DecodeSource(value); err == nil && s.Group != "" {
+			w.sourceGroups[revision] = s.Group
+		}
+	}
+}
+
+// release is the release whose Approve carries module's build fp (ADR 0601 §1), and whether one does: the trunk's value of
+// the module names fp, the source revision at which that fingerprint last changed (FPSrc, never the Src of its last merge,
+// which a recompute with no merge keeps) names the release that moved it, and the gate's merge of that release, which it
+// writes on the operator's Approve, holds the module's own trunk merge among its merged pull requests. Any of them
+// unknown: none, and the move is asked of a person.
+func (w *world) release(module, fp string) (string, bool) {
+	t, ok := w.trunk()[module]
+	if !ok || fp == "" || t.FP2 != fp || t.FPSrc == 0 || t.Commit == "" {
+		return "", false
+	}
+	w.mu.Lock()
+	group := w.sourceGroups[t.FPSrc]
+	w.mu.Unlock()
+	key, err := delivery.MergesKey(group)
+	if group == "" || err != nil {
+		return "", false
+	}
+	raw := w.value(delivery.MergesBucket, key)
+	if raw == nil {
+		return "", false
+	}
+	merge, err := delivery.DecodeMerge(raw)
+	if err != nil {
+		return "", false
+	}
+	for _, pull := range merge.Pulls {
+		if pull.State == delivery.MergeMerged && pull.Commit == t.Commit && delivery.SameRepository(pull.Repository, t.Repository) {
+			return group, true
+		}
+	}
+	return "", false
 }
 
 // metaOf is the revision and time of the value a bucket holds at key, as the watch said them.
@@ -97,12 +129,20 @@ func (w *world) put(bucket, key string, value []byte) {
 	if w.values[bucket] == nil {
 		w.values[bucket] = map[string][]byte{}
 	}
+	w.changes[bucket]++ // the bucket's generation (bucketGen), a delete included
 	if value == nil {
 		delete(w.values[bucket], key)
+		if bucket == delivery.PlacementBucket {
+			_, _ = w.placement.Put(key, nil, 0, true)
+		}
 		return
 	}
 	w.values[bucket][key] = value
 	w.changes[bucket+"|"+key]++
+	if bucket == delivery.PlacementBucket {
+		// A key or value that does not read places nothing new on its node; the indexer's read tool says it.
+		_, _ = w.placement.Put(key, value, 0, false)
+	}
 	if bucket == delivery.HaveBucket {
 		if h, err := delivery.DecodeHave(value); err == nil && h.FP != "" && h.Phase == delivery.PhaseRunning && h.Health == delivery.HealthOK {
 			list := slices.DeleteFunc(w.healthy[key], func(fp string) bool { return fp == h.FP })
@@ -158,6 +198,19 @@ func kvGetter(kv jetstream.KeyValue) getter {
 	}
 }
 
+// getter reads a key of a bucket the world holds: errNotThere where it holds none.
+func (w *world) getter(bucket string) getter {
+	return func(_ context.Context, key string) ([]byte, error) {
+		w.mu.Lock()
+		defer w.mu.Unlock()
+		v, ok := w.values[bucket][key]
+		if !ok {
+			return nil, errNotThere
+		}
+		return v, nil
+	}
+}
+
 // manifest reads the manifest of a digest from the indexer's bucket once and keeps it: a digest's manifest never changes.
 func (w *world) manifest(ctx context.Context, get getter, digest string) parsed {
 	w.mu.Lock()
@@ -180,10 +233,10 @@ func (w *world) manifest(ctx context.Context, get getter, digest string) parsed
 	m, err := delivery.DecodeManifest(value)
 	if err != nil {
 		p = parsed{err: err.Error()}
-	} else if man, err := catalogue.ParseManifestForInputs([]byte(m.JSON)); err != nil {
-		// Read as the indexer reads it (issue 1751): a value falling back to a predefined key is judged by the merge gate
-		// in the catalogue, against the predefined.json at its root that this process never holds (ADR 0348 §7).
-		p = parsed{module: m.Module, err: err.Error()}
+	} else if man, err := catalogue.Decode([]byte(m.JSON)); err != nil {
+		// Decoded, never judged (novox/hq ADR 0578 §3): the indexer's judge judged it, and its verdict is taken from the
+		// module's value where it is read (world.mesh).
+		p = parsed{module: m.Module, err: "it does not decode: " + err.Error()}
 	} else {
 		p = parsed{module: m.Module, manifest: man}
 	}
@@ -193,40 +246,31 @@ func (w *world) manifest(ctx context.Context, get getter, digest string) parsed
 	return p
 }
 
-// assigned is each node's modules both the controller's assignments and the seat mesh-placement's placement name, in name order
-// (ADR 0549 §5; the assignments alone before any placement was read), with every open assignment by node and module.
-func (w *world) assigned() (map[string][]string, map[string]assignment) {
-	byAssignment, all := w.assignedByController()
-	placed, seeded := w.placed()
-	both, _ := assign.Placed(byAssignment, placed, seeded)
-	return both, all
-}
-
-// placementDiffers is every pair the controller's assignments and the seat's placement do not both name.
-func (w *world) placementDiffers() []assign.Pair {
-	byAssignment, _ := w.assignedByController()
-	placed, seeded := w.placed()
-	_, differ := assign.Placed(byAssignment, placed, seeded)
-	return differ
+// assigned is each node's modules the seat mesh-placement's placement names, in name order (ADR 0549 §5, ADR 0567 §8): the
+// placement is the one source of where modules run. The controller's assignments are read no more (issue 774).
+func (w *world) assigned() map[string][]string {
+	placed, _ := w.placed()
+	out := make(map[string][]string, len(placed))
+	for node, modules := range placed {
+		out[node] = slices.Sorted(slices.Values(modules))
+	}
+	return out
 }
 
 // placed is each node's modules in the seat's placement (ADR 0567 §1), and whether any placement key was read: a key
 // that does not read places nothing on its node and is said by the indexer's own read tool.
 func (w *world) placed() (map[string][]string, bool) {
 	out := map[string][]string{}
-	values := w.read(delivery.PlacementBucket)
-	for key, value := range values {
-		node, err := delivery.ParsePlacementKey(key)
-		if err != nil {
-			continue
-		}
-		p, err := delivery.DecodePlacement(value)
-		if err != nil || p.Node != node {
-			continue
-		}
+	for node, p := range w.placements() {
 		out[node] = p.Assigned()
 	}
-	return out, len(values) > 0
+	return out, len(w.read(delivery.PlacementBucket)) > 0
+}
+
+// placements is every node's placement, assembled from its keys in either form (delivery.PlacementKeys).
+func (w *world) placements() map[string]delivery.Placement {
+	out, _ := w.placement.AllRevisions()
+	return out
 }
 
 // placedNodes is every node the seat's placement names (ADR 0567 §1): those compose their own modules (ADR 0547 §2),
@@ -240,24 +284,6 @@ func (w *world) placedNodes() map[string]bool {
 	return out
 }
 
-// assignedByController is each node's modules with an open assignment, read from the controller's assignments, in
-// name order.
-func (w *world) assignedByController() (map[string][]string, map[string]assignment) {
-	out, all := map[string][]string{}, map[string]assignment{}
-	for _, value := range w.read(provider.AssignmentsBucket) {
-		var a assignment
-		if json.Unmarshal(value, &a) != nil || a.Node == "" || a.Module == "" || !a.open() {
-			continue
-		}
-		out[a.Node] = append(out[a.Node], a.Module)
-		all[a.Node+"."+a.Module] = a
-	}
-	for _, mods := range out {
-		sort.Strings(mods)
-	}
-	return out, all
-}
-
 // trunk is every module the indexer holds at the trunk, with its value.
 func (w *world) trunk() map[string]delivery.Module {
 	out := map[string]delivery.Module{}
@@ -273,61 +299,11 @@ func (w *world) trunk() map[string]delivery.Module {
 	return out
 }
 
-// mesh is the mesh as the trunk holds it, for the composition check.
-func (w *world) mesh(ctx context.Context, manifests getter) assign.Mesh {
-	m := assign.Mesh{Manifests: map[string]catalogue.Manifest{}, Unreadable: map[string]string{}, Digests: map[string]string{}}
-	m.Assigned, _ = w.assigned()
-	for name, mod := range w.trunk() {
-		if mod.Manifest == "" {
-			continue
-		}
-		m.Digests[name] = mod.Manifest
-		p := w.manifest(ctx, manifests, mod.Manifest)
-		if p.err != "" {
-			m.Unreadable[name] = p.err
-			continue
-		}
-		m.Manifests[name] = p.manifest
-	}
-	// Once the catalogue places the nodes, the check composes over the input they compose from (ADR 0547 §2, ADR 0549
-	// §3): one composer's input for the check and the nodes. An input that cannot be read is said, and the nodes and their
-	// assignments alone are composed, as before any placement.
-	if _, seeded := w.placed(); seeded {
-		in, err := frombus.Input(ctx, worldReader{w: w, manifests: manifests}, frombus.Mesh{}, frombus.Scope{Every: true})
-		if err != nil {
-			m.InputUnread = err.Error()
-		} else {
-			m.Input = &in
-		}
-	}
-	return m
-}
-
-// worldReader is what the assigner watched as frombus reads the bus: the seat's placement, the indexer's modules, each node's
-// record in its own have key, the manifests by digest; the check reads no config value, own secret or credential (the
-// composition it asks resolves, and stands in for what it does not carry).
-type worldReader struct {
-	w         *world
-	manifests getter
-}
-
-func (r worldReader) Placements(context.Context) (map[string]delivery.Placement, error) {
-	out := map[string]delivery.Placement{}
-	for key, value := range r.w.read(delivery.PlacementBucket) {
-		node, err := delivery.ParsePlacementKey(key)
-		if err != nil {
-			continue
-		}
-		if p, err := delivery.DecodePlacement(value); err == nil && p.Node == node {
-			out[node] = p
-		}
-	}
-	return out, nil
-}
-
-func (r worldReader) Records(context.Context) (map[string]delivery.NodeRecord, error) {
+// records is each node's record in its own have key (`<node>.node`): the nodes a placement proposal is answered by,
+// with those placement names (ADR 0593 §8).
+func (w *world) records() map[string]delivery.NodeRecord {
 	out := map[string]delivery.NodeRecord{}
-	for key, value := range r.w.read(delivery.HaveBucket) {
+	for key, value := range w.read(delivery.HaveBucket) {
 		node, _, isNode, err := delivery.ParseHaveKey(key)
 		if err != nil || !isNode {
 			continue
@@ -336,131 +312,7 @@ func (r worldReader) Records(context.Context) (map[string]delivery.NodeRecord, e
 			out[node] = *h.Record
 		}
 	}
-	return out, nil
-}
-
-func (r worldReader) Modules(context.Context) (map[string]delivery.Module, error) {
-	return r.w.trunk(), nil
-}
-
-func (r worldReader) Manifest(ctx context.Context, digest string) ([]byte, error) {
-	key, err := delivery.ManifestsKey(digest)
-	if err != nil {
-		return nil, err
-	}
-	raw, err := r.manifests(ctx, key)
-	if err != nil {
-		return nil, err
-	}
-	m, err := delivery.DecodeManifest(raw)
-	if err != nil {
-		return nil, err
-	}
-	return []byte(m.JSON), nil
-}
-
-// Values is one module's config values on one node as mesh-config resolved them, each a value its source lays
-// (catalogue.LaidValue): the holder composes every node a proposal touches with them (ADR 0567 §9).
-func (r worldReader) Values(_ context.Context, node, module string) (map[string]any, error) {
-	var out map[string]any
-	prefix := node + "." + module + "."
-	for key, raw := range r.w.read(buscompose.ResolvedBucket) {
-		name, ok := strings.CutPrefix(key, prefix)
-		if !ok || strings.Contains(name, ".") {
-			continue
-		}
-		if v, laid := catalogue.LaidValue(raw); laid {
-			if out == nil {
-				out = map[string]any{}
-			}
-			out[name] = v
-		}
-	}
-	return out, nil
-}
-
-func (worldReader) OwnSecrets(context.Context, string) ([]compose.OwnSecretRow, error) {
-	return nil, nil
-}
-
-func (worldReader) Credentials(context.Context, string, []compose.CredentialKey, []compose.CredentialKey) ([]compose.Credential, []compose.Issued, error) {
-	return nil, nil, nil
-}
-
-// Build and Archive are read only for a node composing itself (frombus.Scope without Every): the check of every node
-// composes from the manifests the indexer read, and reads no build and no archive.
-func (worldReader) Build(context.Context, string, string) (*delivery.BuilderBuild, error) {
-	return nil, nil
-}
-
-func (worldReader) Archive(_ context.Context, url, _ string) ([]byte, error) {
-	return nil, fmt.Errorf("the composition check reads no archive (%s)", url)
-}
-
-func (r worldReader) Served(ctx context.Context, node, module string, keys []string) (map[string]any, error) {
-	all, err := r.Values(ctx, node, module)
-	var out map[string]any
-	for _, k := range keys {
-		if v, ok := all[k]; ok {
-			if out == nil {
-				out = map[string]any{}
-			}
-			out[k] = v
-		}
-	}
-	return out, err
-}
-
-// change is a candidate's change for the composition check, or why the composition waits for it.
-func (w *world) change(ctx context.Context, manifests getter, c delivery.Candidate, trunk map[string]delivery.Module) (assign.Change, string) {
-	ch := assign.Change{Group: c.Group, Heads: c.HeadsHash, Manifests: map[string]catalogue.Manifest{}, Unreadable: map[string]string{},
-		Twice: map[string][]string{}, Digests: map[string]string{}, Members: map[string]string{}}
-	definedIn := map[string]map[string]bool{}
-	for _, p := range c.Pulls {
-		if p.Repository == assign.SDKRepository {
-			ch.SDKHead = p.Head.Head
-		}
-		ch.Members[p.Repository] = p.Head.Head
-		for _, name := range p.Modules {
-			fp, ok := p.Fps[name]
-			if !ok || fp.Manifest == "" {
-				if ok && fp.None2 == noModuleWords {
-					ch.Removed = append(ch.Removed, name)
-					continue
-				}
-				return ch, fmt.Sprintf("the indexer holds no manifest of %s for %s#%d yet", name, p.Repository, p.Number)
-			}
-			if fp.FP2 != "" && fp.FP2 != trunk[name].FP2 {
-				ch.Rebuilt++
-			}
-			got := w.manifest(ctx, manifests, fp.Manifest)
-			if strings.HasPrefix(got.err, "the indexer holds no manifest") {
-				return ch, got.err
-			}
-			ch.Digests[name] = fp.Manifest
-			if got.err != "" {
-				ch.Unreadable[name] = got.err
-				continue
-			}
-			ch.Manifests[got.module] = got.manifest
-			if definedIn[got.module] == nil {
-				definedIn[got.module] = map[string]bool{}
-			}
-			definedIn[got.module][p.Repository] = true
-			if t, ok := trunk[got.module]; ok && t.Repository != "" && t.Repository != p.Repository {
-				definedIn[got.module][t.Repository] = true
-			}
-		}
-	}
-	for name, repos := range definedIn {
-		if len(repos) > 1 {
-			for r := range repos {
-				ch.Twice[name] = append(ch.Twice[name], r)
-			}
-			sort.Strings(ch.Twice[name])
-		}
-	}
-	return ch, ""
+	return out
 }
 
 // online is, by node, whether the watchman holds the node online.
@@ -500,7 +352,8 @@ func (w *world) wantsOf() map[string]map[string]delivery.Want {
 
 // nodes is what the six rules read of the nodes: presence, haves, and every provision's providers with their nodes.
 func (w *world) nodes(manifests map[string]catalogue.Manifest, assigned map[string][]string) assign.Nodes {
-	n := assign.Nodes{Online: map[string]bool{}, Haves: map[string]map[string]delivery.Have{}, Providers: map[string]map[string][]string{}}
+	n := assign.Nodes{Online: map[string]bool{}, Haves: map[string]map[string]delivery.Have{}, Providers: map[string]map[string][]string{},
+		Reads: map[string][]string{}}
 	for key, value := range w.read(delivery.PresenceBucket) {
 		node, _, _, err := delivery.ParsePresenceKey(key)
 		if err != nil || node == "" {
@@ -512,7 +365,14 @@ func (w *world) nodes(manifests map[string]catalogue.Manifest, assigned map[stri
 	}
 	for key, value := range w.read(delivery.HaveBucket) {
 		node, module, isNode, err := delivery.ParseHaveKey(key)
-		if err != nil || isNode {
+		if err != nil {
+			continue
+		}
+		if isNode {
+			// What the node's engine reads (ADR 0614 §4); a record that states none is read as the baseline.
+			if h, err := delivery.DecodeHaveNode(value); err == nil && h.Record != nil {
+				n.Reads[node] = h.Record.ManifestReads
+			}
 			continue
 		}
 		if h, err := delivery.DecodeHave(value); err == nil {
@@ -546,6 +406,10 @@ func (w *world) value(bucket, key string) []byte {
 	return w.values[bucket][key]
 }
 
+// grantsBucket is the bucket the grants are read from: the grants part's state `grants`, always (ADR 0571 clause 9); no
+// manifest but the controller's reads the controller's grants.
+func (w *world) grantsBucket() string { return delivery.PartGrantsBucket }
+
 // has says whether a bucket holds a key now.
 func (w *world) has(bucket, key string) bool {
 	w.mu.Lock()
@@ -570,36 +434,50 @@ func (w *world) built(module, fp string) bool {
 	return err == nil && b.State == delivery.BuildDone
 }
 
-// composed is the controller's composition of module for node at fp: its digest and the judgement of the move to it
-// (mesh-controller_composed `<node>.<module>.<hex>`), and whether it exists and can be read.
-func (w *world) composed(node, module, fp string) (delivery.ComposedDigest, bool) {
-	key, err := delivery.ComposedKey(node, module, fp)
+// buildNeeds are the reference forms the builder's done build of module at fp is written in (the build key's needs, ADR
+// 0618 §1): nil when it is not done or names none.
+func (w *world) buildNeeds(module, fp string) []string {
+	key, err := delivery.BuilderBuildKey(module, fp)
 	if err != nil {
-		return delivery.ComposedDigest{}, false
+		return nil
 	}
-	w.mu.Lock()
-	value, ok := w.values[delivery.ControllerComposedBucket][key]
-	w.mu.Unlock()
-	if !ok {
-		return delivery.ComposedDigest{}, false
+	b, err := delivery.DecodeBuilderBuild(w.value(delivery.BuilderBuildsBucket, key))
+	if err != nil || b.State != delivery.BuildDone {
+		return nil
 	}
-	d, err := delivery.DecodeComposedDigest(value)
-	return d, err == nil
+	return b.Needs
 }
 
-// nodeComposed is, by node, the digest of the node's own composition (mesh-controller_composed `<node>.node`).
-func (w *world) nodeComposed() map[string]delivery.ComposedDigest {
-	out := map[string]delivery.ComposedDigest{}
-	for key, value := range w.read(delivery.ControllerComposedBucket) {
-		node, _, _, isNode, err := delivery.ParseComposedKey(key)
-		if err != nil || !isNode {
-			continue
-		}
-		if d, err := delivery.DecodeComposedDigest(value); err == nil {
-			out[node] = d
-		}
+// recordReads is what node's record `<node>.node` states its engine reads (ADR 0614 §4), and whether the assigner holds
+// a record of it: the fallback where the engine does not answer the verb manifest-reads (enginereads.FromRecord).
+func (w *world) recordReads(node string) ([]string, bool) {
+	r, ok := w.records()[node]
+	return r.ManifestReads, ok
+}
+
+// knownNodes is every node the assigner hears of: placed, with a record, or with a presence.
+func (w *world) knownNodes() []string {
+	set := map[string]bool{}
+	for node := range w.placedNodes() {
+		set[node] = true
 	}
-	return out
+	for node := range w.records() {
+		set[node] = true
+	}
+	for node := range w.online() {
+		set[node] = true
+	}
+	return slices.Sorted(maps.Keys(set))
+}
+
+// composed is the composition of module for node: a placed node composes its own, and its composition is the digest its own
+// have names (ADR 0571 §6); an unplaced node has none, so it gets no want (and the pass says so, unplacedFindings). The
+// controller's copy (mesh-controller_composed) is read no more (issue 774).
+func (w *world) composed(node, module, fp string) (delivery.ComposedDigest, bool) {
+	if !w.placedNodes()[node] {
+		return delivery.ComposedDigest{}, false
+	}
+	return w.ownComposed(node)
 }
 
 // answer is the teller's answer to the ask at key (mesh-delivery-teller_answers, the same key), and whether there is one.
@@ -614,6 +492,14 @@ func (w *world) answer(key string) (delivery.Answer, bool) {
 	return a, err == nil
 }
 
+// bucketGen is how many times any key of the bucket was written or deleted in this process: a read of what it shows
+// elsewhere is asked again only after it moves.
+func (w *world) bucketGen(bucket string) uint64 {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	return w.changes[bucket]
+}
+
 // changed is how many values the key has taken in this process (see world.changes).
 func (w *world) changed(bucket, key string) uint64 {
 	w.mu.Lock()
@@ -621,29 +507,35 @@ func (w *world) changed(bucket, key string) uint64 {
 	return w.changes[bucket+"|"+key]
 }
 
-// runningCommits is, of every open assignment of module, the commit of the build it names, read from the controller's
-// build record (`mesh-controller_builds` `<module>.build.<id>`), distinct and sorted: the commits a reader of the
-// manifests runs at (novox/hq ADR 0482 clause 5, issue 1623). A build whose record names no full commit is left out.
-func (w *world) runningCommits(ctx context.Context, get getter, module string) []string {
-	_, all := w.assigned()
-	seen := map[string]bool{}
-	for _, a := range all {
-		if a.Module != module || a.Build == "" {
-			continue
-		}
-		value, err := get(ctx, delivery.BuildKey(module, a.Build))
-		if err != nil {
-			continue
-		}
-		var rec delivery.BuildRecord
-		if json.Unmarshal(value, &rec) != nil || len(rec.Commit) != 40 {
-			continue
-		}
-		seen[rec.Commit] = true
+// ownComposed is a placed node's own composition, as the digest its own have names (`<node>.node` of the haves, Composed):
+// what rule 7 reads. A node whose have names none is not composed yet.
+func (w *world) ownComposed(node string) (delivery.ComposedDigest, bool) {
+	key, err := delivery.HaveNodeKey(node)
+	if err != nil {
+		return delivery.ComposedDigest{}, false
 	}
-	out := make([]string, 0, len(seen))
-	for c := range seen {
-		out = append(out, c)
+	raw, ok := w.read(delivery.HaveBucket)[key]
+	if !ok {
+		return delivery.ComposedDigest{}, false
+	}
+	h, err := delivery.DecodeHaveNode(raw)
+	if err != nil || h.Composed == "" {
+		return delivery.ComposedDigest{}, false
+	}
+	return delivery.ComposedDigest{V: delivery.Version, Digest: h.Composed, Judgement: delivery.JudgedNeither,
+		Words: "the node composes its own"}, true
+}
+
+// unplacedNodes are the nodes whose engine has a have and that no placement names: they get no
+// want, since nothing composes them.
+func (w *world) unplacedNodes() []string {
+	placed := w.placedNodes()
+	var out []string
+	for key := range w.read(delivery.HaveBucket) {
+		node, _, isNode, err := delivery.ParseHaveKey(key)
+		if err == nil && isNode && !placed[node] {
+			out = append(out, node)
+		}
 	}
 	sort.Strings(out)
 	return out

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/world_test.go

@@ -2,14 +2,12 @@ package main
 
 import (
 	"context"
-	"os"
 	"slices"
 	"strings"
 	"testing"
+	"time"
 
 	"git.novox.be/novox/mesh-sdk/go/delivery"
-
-	"mesh-delivery-assigner/internal/assign"
 )
 
 // fakeManifests is the indexer's manifests bucket in memory.
@@ -44,75 +42,6 @@ func pull(repo string, number int, modules map[string]delivery.CandidateModule)
 	return p
 }
 
-// 1297/B3b: a candidate's change reads each module's manifest by its digest, counts the modules rebuilt, takes a
-// module with no manifest in the preview as removed, a mesh-sdk member's head, and a module the trunk holds from
-// another repository as defined twice.
-func TestTheChangeOfACandidate(t *testing.T) {
-	theWorldCountsTheValuesAKeyTakes(t)
-	f := fakeManifests{}
-	web := f.add(t, "web", `{"module":"web","version":"2"}`)
-	mail := f.add(t, "mail", `{"module":"mail","version":"1"}`)
-	trunk := map[string]delivery.Module{"web": {FP2: fp('a'), Repository: "novox/web"}, "mail": {FP2: fp('c'), Repository: "novox/mail"}}
-	c := delivery.Candidate{Group: "g", HeadsHash: "0123456789ab", Pulls: []delivery.CandidatePull{
-		pull("novox/web", 1, map[string]delivery.CandidateModule{"web": {FP2: fp('b'), Manifest: web}, "old": {None2: noModuleWords}}),
-		pull("novox/other", 2, map[string]delivery.CandidateModule{"mail": {FP2: fp('c'), Manifest: mail}}),
-		pull(assign.SDKRepository, 3, nil),
-	}}
-	ch, waits := newWorld().change(context.Background(), f.get, c, trunk)
-	if waits != "" {
-		t.Fatalf("the change waits: %s", waits)
-	}
-	if ch.Manifests["web"].Version != "2" || ch.Rebuilt != 1 || !slices.Equal(ch.Removed, []string{"old"}) || ch.SDKHead != strings.Repeat("3", 40) {
-		t.Errorf("change = %+v", ch)
-	}
-	if !slices.Equal(ch.Twice["mail"], []string{"novox/mail", "novox/other"}) || len(ch.Twice) != 1 {
-		t.Errorf("twice = %v, want mail in novox/mail and novox/other", ch.Twice)
-	}
-}
-
-// 1297/B3b: a candidate whose module has no manifest digest yet, or whose manifest the indexer does not hold yet, waits,
-// saying for what; an unreadable manifest is the change's, not a wait.
-func TestAChangeWaitsForItsManifests(t *testing.T) {
-	f := fakeManifests{}
-	bad := f.add(t, "web", `{"module":"web","version":"2","scope":"x"}`)
-	for _, c := range []delivery.CandidatePull{
-		pull("novox/web", 1, map[string]delivery.CandidateModule{"web": {None2: "no preview yet"}}),
-		pull("novox/web", 1, map[string]delivery.CandidateModule{"web": {FP2: fp('b'), Manifest: strings.Repeat("9", 64)}}),
-	} {
-		_, waits := newWorld().change(context.Background(), f.get, delivery.Candidate{Group: "g", HeadsHash: "0123456789ab", Pulls: []delivery.CandidatePull{c}}, nil)
-		if waits == "" {
-			t.Errorf("a change without its manifest %+v does not wait", c.Fps)
-		}
-	}
-	ch, waits := newWorld().change(context.Background(), f.get, delivery.Candidate{Group: "g", HeadsHash: "0123456789ab",
-		Pulls: []delivery.CandidatePull{pull("novox/web", 1, map[string]delivery.CandidateModule{"web": {FP2: fp('b'), Manifest: bad}})}}, nil)
-	if waits != "" || ch.Unreadable["web"] == "" {
-		t.Errorf("an unreadable manifest: waits %q, change %+v", waits, ch)
-	}
-}
-
-// A manifest of the change whose config value falls back to a predefined key (novox/hq ADR 0348 §7) is read, not
-// unreadable for the catalogue's predefined.json the assigner never holds: the merge gate judges the fallback in the
-// catalogue, and the indexer reads it the same way (catalogue.ParseManifestForInputs, issue 1751). A group whose
-// mesh-catalog member touched pacman and xterm failed its composition on this (group check 18df81380db3). The manifest is
-// xterm's module.json from mesh-catalog at 835bf22b.
-func TestAManifestFallingBackToAPredefinedKeyIsReadable(t *testing.T) {
-	raw, err := os.ReadFile("testdata/catalogue-835bf22b-xterm.module.json")
-	if err != nil {
-		t.Fatal(err)
-	}
-	if !strings.Contains(string(raw), `"predefined"`) {
-		t.Fatal("the fixture names no predefined key")
-	}
-	f := fakeManifests{}
-	xterm := f.add(t, "xterm", string(raw))
-	ch, waits := newWorld().change(context.Background(), f.get, delivery.Candidate{Group: "g", HeadsHash: "0123456789ab",
-		Pulls: []delivery.CandidatePull{pull("novox/mesh-catalog", 1, map[string]delivery.CandidateModule{"xterm": {FP2: fp('b'), Manifest: xterm}})}}, nil)
-	if waits != "" || ch.Unreadable["xterm"] != "" || ch.Manifests["xterm"].Module != "xterm" {
-		t.Errorf("xterm: waits %q, unreadable %q, want read", waits, ch.Unreadable["xterm"])
-	}
-}
-
 // Review round 1 (items 3 and 4): the world counts the values a key takes, so a have written again after an answer is seen.
 func theWorldCountsTheValuesAKeyTakes(t *testing.T) {
 	w := newWorld()
@@ -125,4 +54,27 @@ func theWorldCountsTheValuesAKeyTakes(t *testing.T) {
 	if got := w.changed(delivery.HaveBucket, "gone"); got != 0 {
 		t.Errorf("changed = %d for a key never seen", got)
 	}
+	// ADR 0571 clause 9: grants are read from the grants part's bucket, the one bucket of grants (ADR 0590).
+	fp := delivery.SourcePrefix2 + strings.Repeat("d", 64)
+	gkey, _ := delivery.PartGrantKey("web", fp)
+	grant, _ := delivery.EncodeGrant(delivery.Grant{Accounts: []string{"ace.web"}})
+	for _, row := range []struct {
+		name    string
+		inPart  bool
+		granted bool
+	}{
+		{"the part's grant", true, true},
+		{"no grant", false, false},
+	} {
+		p := newPasser(buckets{}, time.Now())
+		if row.inPart {
+			p.w.put(delivery.PartGrantsBucket, gkey, grant)
+		}
+		if got := p.w.grantsBucket(); got != delivery.PartGrantsBucket {
+			t.Errorf("%s: grants are read from %s, want the part's", row.name, got)
+		}
+		if _, granted := p.composedFor("ace", "web", fp); granted != row.granted {
+			t.Errorf("%s: granted = %v, want %v", row.name, granted, row.granted)
+		}
+	}
 }

modules/mesh-delivery-assigner/go.mod

@@ -3,20 +3,32 @@ module mesh-delivery-assigner
 go 1.26.0
 
 require (
-	git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028212605-77b48a4f1aff
+	git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261104174359-05b3e2e1b94f
 	github.com/nats-io/nats-server/v2 v2.11.17
 	github.com/nats-io/nats.go v1.54.0
 )
 
 require (
-	github.com/antithesishq/antithesis-sdk-go v0.7.0-default-no-op // indirect
+	git.novox.be/novox/mesh-contracts/go v0.0.0-20261104174344-ae5266e77639 // indirect
+	github.com/antithesishq/antithesis-sdk-go v0.8.0-default-no-op // indirect
 	github.com/google/go-tpm v0.9.8 // indirect
-	github.com/klauspost/compress v1.20.0 // indirect
+	github.com/klauspost/compress v1.20.1 // indirect
 	github.com/minio/highwayhash v1.0.4 // indirect
-	github.com/nats-io/jwt/v2 v2.8.1 // indirect
+	github.com/nats-io/jwt/v2 v2.8.2 // indirect
 	github.com/nats-io/nkeys v0.4.16 // indirect
 	github.com/nats-io/nuid v1.0.1 // indirect
 	golang.org/x/crypto v0.57.0 // indirect
 	golang.org/x/sys v0.48.0 // indirect
-	golang.org/x/time v0.15.0 // indirect
+	golang.org/x/time v0.16.0 // indirect
 )
+
+require git.novox.be/novox/mesh-delivery/sdk v0.0.0-00010101000000-000000000000
+
+require (
+	git.novox.be/novox/mesh-contracts/go/clients/nodeengineclient v0.0.0-20261104174344-ae5266e77639
+	git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient v0.0.0-20261104174344-ae5266e77639
+	git.novox.be/novox/mesh-contracts/go/seats/nodeengine v0.0.0-20261104174344-ae5266e77639
+	git.novox.be/novox/mesh-contracts/go/seats/operatorchannel v0.0.0-20261104174344-ae5266e77639
+)
+
+replace git.novox.be/novox/mesh-delivery/sdk => ../../sdk

modules/mesh-delivery-assigner/go.sum

@@ -1,15 +1,25 @@
-git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028212605-77b48a4f1aff h1:EHuM+ed+/M9woMZsMou6/2xm6hIdb1YCFINprrP54Ys=
-git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028212605-77b48a4f1aff/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
-github.com/antithesishq/antithesis-sdk-go v0.7.0-default-no-op h1:Z/MZK75wC/NSrkgqeNIa7jexam9uWzhLmFTSCPI/kn0=
-github.com/antithesishq/antithesis-sdk-go v0.7.0-default-no-op/go.mod h1:FQyySiasQQM8735Ddel3MRojmy4dA1IqCeyJ5jmPMbI=
+git.novox.be/novox/mesh-contracts/go v0.0.0-20261104174344-ae5266e77639 h1:Zt7CfWt2S2W/fVgWNyW2u2+xwz051LXvGxVTNIyfhdM=
+git.novox.be/novox/mesh-contracts/go v0.0.0-20261104174344-ae5266e77639/go.mod h1:0dD1XEJBJ0G5UYDQxSZI84nuujb6m3tOpJl4C8rQVvg=
+git.novox.be/novox/mesh-contracts/go/clients/nodeengineclient v0.0.0-20261104174344-ae5266e77639 h1:3FTxvHrv3Hv+ZUbp/ezTrndqdgiS+Z6EUG2XGYJNJr8=
+git.novox.be/novox/mesh-contracts/go/clients/nodeengineclient v0.0.0-20261104174344-ae5266e77639/go.mod h1:/V/1wfyQwjE9VbPLsFtkf6uX+SHKUXX34s5JscDuGAs=
+git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient v0.0.0-20261104174344-ae5266e77639 h1:19PhtrCOwia711Oqdyafvs5EKTVmmgk5Gdb4leCkq3w=
+git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient v0.0.0-20261104174344-ae5266e77639/go.mod h1:Dj6fbL8Evgy72EWO3Gl3L3Ra8N/nJSzgEVwSGmeRam0=
+git.novox.be/novox/mesh-contracts/go/seats/nodeengine v0.0.0-20261104174344-ae5266e77639 h1:YQ6eJvc+RYUVIVf+oX+R4TC1dYL8TLLMZ0/JPDU1tp4=
+git.novox.be/novox/mesh-contracts/go/seats/nodeengine v0.0.0-20261104174344-ae5266e77639/go.mod h1:TB20TsQuOd5aer+cXL6PbaYyg2RvgL1R4MzD61Oks3A=
+git.novox.be/novox/mesh-contracts/go/seats/operatorchannel v0.0.0-20261104174344-ae5266e77639 h1:K/1yIkqAWKGtLEtJ0PibijIdpo5YATL/9IUVXFoEglM=
+git.novox.be/novox/mesh-contracts/go/seats/operatorchannel v0.0.0-20261104174344-ae5266e77639/go.mod h1:osh0jQyNqYDM27tbxQo6HeUEXgLq9XUewKzNhUXadog=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261104174359-05b3e2e1b94f h1:jDsfDMd48MXY9Zershc3eRxnhmx2sSpUfQkLq5jAIds=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261104174359-05b3e2e1b94f/go.mod h1:08OomDXdwVN8/87nyDtv5R3rH/6LoP8SFFXz30bTYCM=
+github.com/antithesishq/antithesis-sdk-go v0.8.0-default-no-op h1:1BOWQJweNyvZMlpAHXGLiZQn9S+QXGcz3xh94lC0w6E=
+github.com/antithesishq/antithesis-sdk-go v0.8.0-default-no-op/go.mod h1:FQyySiasQQM8735Ddel3MRojmy4dA1IqCeyJ5jmPMbI=
 github.com/google/go-tpm v0.9.8 h1:slArAR9Ft+1ybZu0lBwpSmpwhRXaa85hWtMinMyRAWo=
 github.com/google/go-tpm v0.9.8/go.mod h1:h9jEsEECg7gtLis0upRBQU+GhYVH6jMjrFxI8u6bVUY=
-github.com/klauspost/compress v1.20.0 h1:a3C1ke2ohxFymNlb2HWAHjDeKCI90scRskErZkR0ezA=
-github.com/klauspost/compress v1.20.0/go.mod h1:LUdAzn7YLVvxLpc7y3V1m40wESHTgc1422pwwBSKYuI=
+github.com/klauspost/compress v1.20.1 h1:T7kKElXUMXrUJ2E9QhQhxFtcK5rPyLdsGZvdbLMPdiQ=
+github.com/klauspost/compress v1.20.1/go.mod h1:LUdAzn7YLVvxLpc7y3V1m40wESHTgc1422pwwBSKYuI=
 github.com/minio/highwayhash v1.0.4 h1:asJizugGgchQod2ja9NJlGOWq4s7KsAWr5XUc9Clgl4=
 github.com/minio/highwayhash v1.0.4/go.mod h1:GGYsuwP/fPD6Y9hMiXuapVvlIUEhFhMTh0rxU3ik1LQ=
-github.com/nats-io/jwt/v2 v2.8.1 h1:V0xpGuD/N8Mi+fQNDynXohVvp7ZztevW5io8CUWlPmU=
-github.com/nats-io/jwt/v2 v2.8.1/go.mod h1:nWnOEEiVMiKHQpnAy4eXlizVEtSfzacZ1Q43LIRavZg=
+github.com/nats-io/jwt/v2 v2.8.2 h1:XXRgB60MSTnqsRwejQurVDs/hcv2dkt+86GjI+I/bMc=
+github.com/nats-io/jwt/v2 v2.8.2/go.mod h1:Ag/56sq9OblL4JgdYufDd16Egb17Kr/8WwwuO/forVc=
 github.com/nats-io/nats-server/v2 v2.11.17 h1:GKEghcFK6A+aFx11Yf1LjgLC3txAwvyhnYzhBIQZA8I=
 github.com/nats-io/nats-server/v2 v2.11.17/go.mod h1:B1sFVz4StNosQ903ak4N1G01Fl/9f8e06mXpFIE2K24=
 github.com/nats-io/nats.go v1.54.0 h1:vsXoOxjHp/GmPUN+EcI7uOf/uB+iAP+kEsAFNQN0yzA=
@@ -23,5 +33,5 @@ golang.org/x/crypto v0.57.0/go.mod h1:Fdz0i5U6CoizGwLda9DttjSk6qlZo25zYNtR+ycvuZ
 golang.org/x/sys v0.21.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/sys v0.48.0 h1:bbX/i/6MgT9BVLM9RT1thmxL04yeTAhbEz4SyadbXoo=
 golang.org/x/sys v0.48.0/go.mod h1:hNLxWAXmnKAxqDtdwIYC4bM9oQPEecfsnNMuSxOs3og=
-golang.org/x/time v0.15.0 h1:bbrp8t3bGUeFOx08pvsMYRTCVSMk89u4tKbNOZbp88U=
-golang.org/x/time v0.15.0/go.mod h1:Y4YMaQmXwGQZoFaVFk4YpCt4FLQMYKZe9oeV/f4MSno=
+golang.org/x/time v0.16.0 h1:vMb6ptszcQMkcwiRTAuNNU50gom6++Q/6gY2hDM6VDE=
+golang.org/x/time v0.16.0/go.mod h1:rVKOqvZeKvrDKTQiAHJ7wmwP0RzleSphoEA9RcdLA0s=

modules/mesh-delivery-assigner/internal/assign/askjson.go

@@ -0,0 +1,68 @@
+package assign
+
+import (
+	"encoding/json"
+	"fmt"
+	"time"
+
+	occ "git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient"
+	oc "git.novox.be/novox/mesh-contracts/go/seats/operatorchannel"
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// assignerAsk is the asking-th ask a, as the asks state holds it: the router's ask as JSON (delivery.AssignerAsk.Ask).
+func assignerAsk(asking int, a oc.Ask) delivery.AssignerAsk {
+	raw, err := json.Marshal(a)
+	if err != nil { // an oc.Ask holds only strings, bools and a slice of them: it cannot fail
+		panic(fmt.Sprintf("assign: the ask %q does not marshal: %v", a.ID, err))
+	}
+	return delivery.AssignerAsk{Asking: asking, Ask: raw}
+}
+
+// AskOf is the router's ask an asks-state value carries.
+func AskOf(a delivery.AssignerAsk) (oc.Ask, error) {
+	var ask oc.Ask
+	if err := json.Unmarshal(a.Ask, &ask); err != nil {
+		return oc.Ask{}, fmt.Errorf("assign: the value carries no router's ask: %w", err)
+	}
+	return ask, nil
+}
+
+// EncodeAsk is delivery.EncodeAssignerAsk at key, after the checks every keeper of an ask owes (occ.Carried, ADR 0627 §4):
+// the ask's id is delivery.AskingID(key, asking), and it offers at least one option.
+func EncodeAsk(key string, a delivery.AssignerAsk) ([]byte, error) {
+	if _, err := checkedAsk(key, a); err != nil {
+		return nil, err
+	}
+	return delivery.EncodeAssignerAsk(key, a)
+}
+
+func checkedAsk(key string, a delivery.AssignerAsk) (oc.Ask, error) {
+	ask, err := occ.Carried(a.Ask, delivery.AskingID(key, a.Asking))
+	if err != nil {
+		return oc.Ask{}, fmt.Errorf("assign: %w", err)
+	}
+	return ask, nil
+}
+
+// DecodeAsk reads the ask at key (delivery.DecodeAssignerAsk) with the router's ask it carries.
+func DecodeAsk(key string, data []byte) (delivery.AssignerAsk, oc.Ask, error) {
+	a, err := delivery.DecodeAssignerAsk(key, data)
+	if err != nil {
+		return delivery.AssignerAsk{}, oc.Ask{}, err
+	}
+	ask, err := checkedAsk(key, a)
+	if err != nil {
+		return delivery.AssignerAsk{}, oc.Ask{}, err
+	}
+	return a, ask, nil
+}
+
+// ExpiresAt is when the ask ends unanswered; the zero time for an ask that names none.
+func ExpiresAt(a oc.Ask) time.Time {
+	t, err := occ.Time(a.Expires)
+	if err != nil {
+		return time.Time{}
+	}
+	return t
+}

modules/mesh-delivery-assigner/internal/assign/asks.go

@@ -6,7 +6,8 @@ import (
 	"strings"
 	"time"
 
-	"git.novox.be/novox/mesh-sdk/go/asks"
+	occ "git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient"
+	oc "git.novox.be/novox/mesh-contracts/go/seats/operatorchannel"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
 )
 
@@ -15,21 +16,21 @@ import (
 // record's: the machine whose health check failed and the hold's words (issue 1906). asking numbers the writing: 0 the first, a
 // larger number an ask written again after a hold lifted by itself, so the router takes it as new.
 func HoldAsk(key, module, fp, node, words string, asking int, now time.Time) delivery.AssignerAsk {
-	return delivery.AssignerAsk{Asking: asking, Ask: asks.Ask{
+	return assignerAsk(asking, oc.Ask{
 		ID:       delivery.AskingID(key, asking),
 		Headline: fmt.Sprintf("%s is held at %s", module, short(fp)),
 		Explanation: fmt.Sprintf("The health check of %s failed on %s at %s (%s), so the assigner holds that version and wants "+
 			"no node to move to it. It lifts the hold by itself once every node that runs %s runs it healthy; releasing it "+
 			"lets the wants move to it now.", module, node, short(fp), words, module),
-		Options: []asks.Option{
-			{ID: "keep", Label: "Keep it held", Does: "the version stays held", Level: asks.Acknowledge},
-			{ID: "release", Label: "Release it", Does: "the version is released and the wants move to it by the rules again", Level: asks.Acknowledge},
+		Options: []oc.Option{
+			{ID: "keep", Label: "Keep it held", Does: "the version stays held", Level: occ.Acknowledge},
+			{ID: "release", Label: "Release it", Does: "the version is released and the wants move to it by the rules again", Level: occ.Acknowledge},
 		},
-		Who:      asks.Operator,
-		Expires:  now.Add(7 * 24 * time.Hour),
+		Who:      occ.Operator,
+		Expires:  occ.FormatTime(now.Add(7 * 24 * time.Hour)),
 		OnExpiry: "the version stays held",
 		About:    key,
-	}}
+	})
 }
 
 // The options of the restore ask (ADR 0537 §3, ADR 0539 §19), and what each does on the node.
@@ -42,41 +43,41 @@ const (
 // not set back by itself, since a set-back would lose the writes made since. words is the check's words. Restore sets the
 // node back to the last healthy fingerprint and loses the newer writes; leaving it stopped keeps the data as it is.
 func RestoreAsk(key, node, module, fp, words string, now time.Time) delivery.AssignerAsk {
-	return delivery.AssignerAsk{Ask: asks.Ask{
+	return assignerAsk(0, oc.Ask{
 		ID:       delivery.AskingID(key, 0),
 		Headline: fmt.Sprintf("%s failed its health check on %s", module, node),
 		Explanation: fmt.Sprintf("%s holds data, and its health check failed on %s at %s: %s. Setting it back to the version that ran healthy "+
 			"would lose the writes made since; leaving it stopped keeps the data as it is.", module, node, short(fp), words),
-		Options: []asks.Option{
-			{ID: OptionRestore, Label: "Restore it", Does: "the node is set back to the last healthy version and the newer writes are lost", Level: asks.Acknowledge},
-			{ID: OptionLeaveStopped, Label: "Leave it stopped", Does: "the module stays as it is on the node and the data is kept", Level: asks.Acknowledge},
+		Options: []oc.Option{
+			{ID: OptionRestore, Label: "Restore it", Does: "the node is set back to the last healthy version and the newer writes are lost", Level: occ.Acknowledge},
+			{ID: OptionLeaveStopped, Label: "Leave it stopped", Does: "the module stays as it is on the node and the data is kept", Level: occ.Acknowledge},
 		},
-		Who:      asks.Operator,
-		Expires:  now.Add(7 * 24 * time.Hour),
+		Who:      occ.Operator,
+		Expires:  occ.FormatTime(now.Add(7 * 24 * time.Hour)),
 		OnExpiry: "the module stays as it is on the node",
 		About:    key,
-	}}
+	})
 }
 
 // HeldCondition is the condition the assigner raises when it holds a fingerprint of a module (ADR 0429 §6, ADR 0539 §19), or
 // clears (raised false) when the hold is released. It names the module, the node whose health check failed and the check's
 // words, under the assigner's own name (ADR 0437 clause 9), keyed by the held fingerprint. needsYou is true for a module holding
 // data, whose restore ask waits for the operator.
-func HeldCondition(module, fp, node, words string, raised, needsYou bool) asks.Condition {
+func HeldCondition(module, fp, node, words string, raised, needsYou bool) oc.Condition {
 	key := delivery.AssignerModule + ".held." + module + "." + strings.TrimPrefix(fp, delivery.SourcePrefix2)
-	subject := asks.Scope{Scope: "module", ID: module, Machine: node}
+	subject := oc.ConditionSubject{Scope: "module", ID: module, Machine: node}
 	if !raised {
-		return asks.Condition{Key: key, Subject: subject, State: asks.StateCleared}
+		return oc.Condition{Key: key, Subject: subject, State: occ.StateCleared}
 	}
-	c := asks.Condition{Key: key, Severity: asks.SeverityWarning, Subject: subject, State: asks.StateRaised,
+	c := oc.Condition{Key: key, Severity: occ.SeverityWarning, Subject: subject, State: occ.StateRaised,
 		Summary:  fmt.Sprintf("%s is held at %s", module, short(fp)),
 		Headline: fmt.Sprintf("%s is held at %s", module, short(fp))}
 	what := fmt.Sprintf("The health check of %s failed on %s at %s: %s. The assigner holds that version and wants no node to move to it.", module, node, short(fp), words)
 	if needsYou {
 		c.Needs = "answer whether to restore " + module + " on " + node
-		c.Explanation = asks.NeedsYou + c.Needs + ". " + what
+		c.Explanation = occ.NeedsYou + c.Needs + ". " + what
 	} else {
-		c.Explanation = asks.NothingToDo + " " + what + " Nodes that wanted it are set back to the version that ran healthy."
+		c.Explanation = occ.NothingToDo + " " + what + " Nodes that wanted it are set back to the version that ran healthy."
 	}
 	return c
 }
@@ -85,22 +86,22 @@ func HeldCondition(module, fp, node, words string, raised, needsYou bool) asks.C
 // node while other nodes run it healthy (ADR 0557 §1, issue 1496): the failure is the node's, so nothing is held or set back and
 // the node keeps its want. It names the node, the module, fp and the have's words, keyed by node and module, and is cleared
 // (raised false) once the node no longer fails alone.
-func NodeFailedCondition(node, module, fp string, f NodeFailure, raised bool) asks.Condition {
+func NodeFailedCondition(node, module, fp string, f NodeFailure, raised bool) oc.Condition {
 	key := delivery.AssignerModule + ".failed-alone." + node + "." + module
-	subject := asks.Scope{Scope: "module", ID: module, Machine: node}
+	subject := oc.ConditionSubject{Scope: "module", ID: module, Machine: node}
 	if !raised {
-		return asks.Condition{Key: key, Subject: subject, State: asks.StateCleared,
+		return oc.Condition{Key: key, Subject: subject, State: occ.StateCleared,
 			Resolved: fmt.Sprintf("%s on %s no longer fails its health check alone.", module, node)}
 	}
 	headline := fmt.Sprintf("%s fails on %s alone", module, node)
-	if n := len([]rune(headline)); n > asks.HeadlineLength {
-		headline = string([]rune(headline)[:asks.HeadlineLength])
+	if n := len([]rune(headline)); n > occ.HeadlineLength {
+		headline = string([]rune(headline)[:occ.HeadlineLength])
 	}
-	return asks.Condition{Key: key, Severity: asks.SeverityWarning, Subject: subject, State: asks.StateRaised,
+	return oc.Condition{Key: key, Severity: occ.SeverityWarning, Subject: subject, State: occ.StateRaised,
 		Summary: headline, Headline: headline,
 		Explanation: fmt.Sprintf("%s The health check of %s at %s failed on %s (%s), while it runs healthy on %s. The failure is %s's, "+
 			"so the assigner holds nothing and sets no node back, and %s keeps its want. This clears once %s runs it healthy or "+
-			"another version is the newest.", asks.NothingToDo, module, short(fp), node, f.Words, strings.Join(f.Others, ", "), node,
+			"another version is the newest.", occ.NothingToDo, module, short(fp), node, f.Words, strings.Join(f.Others, ", "), node,
 			node, node)}
 }
 
@@ -108,36 +109,28 @@ func NodeFailedCondition(node, module, fp string, f NodeFailure, raised bool) as
 // gives up every module with a fingerprint of the new form, so nothing applies it there and its files are gone. It is raised (urgent)
 // naming the module, the node and the rule holding its first want back with the rule's words, under the assigner's own name keyed by
 // node and module, and cleared (raised false) when the node has a want for it again.
-func NeitherCondition(node, module string, h Holding, raised bool) asks.Condition {
+func NeitherCondition(node, module string, h Holding, raised bool) oc.Condition {
 	key := delivery.AssignerModule + ".neither." + node + "." + module
-	subject := asks.Scope{Scope: "module", ID: module, Machine: node}
+	subject := oc.ConditionSubject{Scope: "module", ID: module, Machine: node}
 	if !raised {
-		return asks.Condition{Key: key, Subject: subject, State: asks.StateCleared,
+		return oc.Condition{Key: key, Subject: subject, State: occ.StateCleared,
 			Resolved: fmt.Sprintf("%s on %s has a want again, so its own composition is applied there.", module, node)}
 	}
 	headline := fmt.Sprintf("%s on %s is on no list", module, node)
-	if n := len([]rune(headline)); n > asks.HeadlineLength {
-		headline = string([]rune(headline)[:asks.HeadlineLength])
+	if n := len([]rune(headline)); n > occ.HeadlineLength {
+		headline = string([]rune(headline)[:occ.HeadlineLength])
 	}
-	if h.Bus {
-		needs := fmt.Sprintf("put %s on %s with assigner_put", module, node)
-		return asks.Condition{Key: key, Severity: asks.SeverityUrgent, Subject: subject, State: asks.StateRaised,
-			Summary: headline, Headline: headline, Needs: needs,
-			Explanation: fmt.Sprintf("%s%s. %s is assigned to %s, but the node holds no want for it and the node's own composition does not "+
-				"hold it either, so nothing applies it there. The assigner never moves the bus: %s. This clears once the node has a want for it.",
-				asks.NeedsYou, needs, module, node, h.Words)}
-	}
-	return asks.Condition{Key: key, Severity: asks.SeverityUrgent, Subject: subject, State: asks.StateRaised,
+	return oc.Condition{Key: key, Severity: occ.SeverityUrgent, Subject: subject, State: occ.StateRaised,
 		Summary: headline, Headline: headline,
 		Explanation: fmt.Sprintf("%s %s is assigned to %s, but the node holds no want for it and the node's own composition does not "+
 			"hold it either, so nothing applies it there. The assigner's rule %d holds its first want back: %s. The assigner writes the want once the "+
-			"rule holds, and clears this.", asks.NothingToDo, module, node, h.Rule, h.Words)}
+			"rule holds, and clears this.", occ.NothingToDo, module, node, h.Rule, h.Words)}
 }
 
 // NeitherLeftCondition clears the neither condition of module on node when it is no longer on neither list: why is "" when the
 // node has a live want for it again, else why it has none (it is held, its move waits for an ask, the node no longer runs it), so
 // the clear never says a want the node does not hold (issue 1945: "nats on novox has a want again" while it had none).
-func NeitherLeftCondition(node, module, why string) asks.Condition {
+func NeitherLeftCondition(node, module, why string) oc.Condition {
 	c := NeitherCondition(node, module, Holding{}, false)
 	if why != "" {
 		c.Resolved = fmt.Sprintf("%s on %s is no longer on neither list and has no want: %s.", module, node, why)
@@ -146,7 +139,7 @@ func NeitherLeftCondition(node, module, why string) asks.Condition {
 }
 
 // LiftedCondition clears the condition of a held fingerprint the assigner lifted by itself, saying why (issue 1906).
-func LiftedCondition(module, fp string) asks.Condition {
+func LiftedCondition(module, fp string) oc.Condition {
 	c := HeldCondition(module, fp, "", "", false, false)
 	c.Resolved = LiftedWords(module, fp) + "."
 	return c
@@ -169,20 +162,20 @@ func RecordAsk(key, node, module, fp string, need RecordNeed, now time.Time) del
 		delivery.JudgedMovesData: "moves the module's data",
 		delivery.JudgedCannot:    "cannot be judged: " + need.Words,
 	}[need.Judgement]
-	return delivery.AssignerAsk{Ask: asks.Ask{
+	return assignerAsk(0, oc.Ask{
 		ID:       delivery.AskingID(key, 0),
 		Headline: fmt.Sprintf("%s waits for your yes on %s", module, node),
 		Explanation: fmt.Sprintf("%s is recorded: a person takes each of its moves. The next one on %s (version %s) %s. "+
 			"The node is told to apply it only after you say yes.", module, node, short(fp), what),
-		Options: []asks.Option{
-			{ID: OptionYes, Label: "Yes, move it", Does: "the node is told to apply the new composition of " + module, Level: asks.Acknowledge},
-			{ID: OptionNo, Label: "No, not now", Does: "the node keeps what it runs", Level: asks.Acknowledge},
+		Options: []oc.Option{
+			{ID: OptionYes, Label: "Yes, move it", Does: "the node is told to apply the new composition of " + module, Level: occ.Acknowledge},
+			{ID: OptionNo, Label: "No, not now", Does: "the node keeps what it runs", Level: occ.Acknowledge},
 		},
-		Who:      asks.Operator,
-		Expires:  now.Add(7 * 24 * time.Hour),
+		Who:      occ.Operator,
+		Expires:  occ.FormatTime(now.Add(7 * 24 * time.Hour)),
 		OnExpiry: "the node keeps what it runs",
 		About:    key,
-	}}
+	})
 }
 
 // NextBackupAsking is the number of the asking that follows the one numbered after (a negative number: none yet). Numbers 0 and 1
@@ -200,7 +193,11 @@ var backupDigest = regexp.MustCompile(`\(composition (sha256:[0-9a-f]{64})\)`)
 // none. An answer is taken for the composition of the ask it answers, and a new revision at the same fingerprint is asked again
 // under a new number (ADR 0539 §16).
 func BackupAskDigest(a delivery.AssignerAsk) string {
-	if m := backupDigest.FindStringSubmatch(a.Ask.Explanation); m != nil {
+	ask, err := AskOf(a)
+	if err != nil {
+		return ""
+	}
+	if m := backupDigest.FindStringSubmatch(ask.Explanation); m != nil {
 		return m[1]
 	}
 	return ""
@@ -216,33 +213,33 @@ func BackupAnswerWords(option string, asking int) string {
 // without a backup. digest is the composition about to be applied and asking the number of the asking, 0 the first; words are the
 // backup's own words, from the node's have.
 func BackupAsk(key, node, module, fp, digest, words string, asking int, now time.Time) delivery.AssignerAsk {
-	return delivery.AssignerAsk{Asking: asking, Ask: asks.Ask{
+	return assignerAsk(asking, oc.Ask{
 		ID:       delivery.AskingID(key, asking),
 		Headline: fmt.Sprintf("The backup of %s failed on %s", module, node),
 		Explanation: fmt.Sprintf("The backup before applying %s at %s on %s failed: %s. %s keeps running what it has until you answer. (composition %s)",
 			module, short(fp), node, words, module, digest),
-		Options: []asks.Option{
-			{ID: OptionBackupAgain, Label: "Back up again", Does: "the node tries the backup again before it applies", Level: asks.Acknowledge},
-			{ID: OptionBackupSkip, Label: "Go on without a backup", Does: "the node applies the new version without a backup", Level: asks.Acknowledge},
+		Options: []oc.Option{
+			{ID: OptionBackupAgain, Label: "Back up again", Does: "the node tries the backup again before it applies", Level: occ.Acknowledge},
+			{ID: OptionBackupSkip, Label: "Go on without a backup", Does: "the node applies the new version without a backup", Level: occ.Acknowledge},
 		},
-		Who:      asks.Operator,
-		Expires:  now.Add(7 * 24 * time.Hour),
+		Who:      occ.Operator,
+		Expires:  occ.FormatTime(now.Add(7 * 24 * time.Hour)),
 		OnExpiry: "the module keeps running what it has",
 		About:    key,
-	}}
+	})
 }
 
 // BackupCondition is the condition raised when a backup before an apply fails and the module is held on the node (ADR 0539 §16),
 // naming the node, the module and the backup's words; cleared under the same key.
-func BackupCondition(node, module, fp, words string, raised bool) asks.Condition {
+func BackupCondition(node, module, fp, words string, raised bool) oc.Condition {
 	key := delivery.AssignerModule + ".backup." + node + "." + module + "." + strings.TrimPrefix(fp, delivery.SourcePrefix2)
-	subject := asks.Scope{Scope: "module", ID: module, Machine: node}
+	subject := oc.ConditionSubject{Scope: "module", ID: module, Machine: node}
 	if !raised {
-		return asks.Condition{Key: key, Subject: subject, State: asks.StateCleared}
+		return oc.Condition{Key: key, Subject: subject, State: occ.StateCleared}
 	}
 	headline := fmt.Sprintf("The backup of %s failed on %s", module, node)
 	needs := "answer whether to back up again or go on without a backup"
-	return asks.Condition{Key: key, Severity: asks.SeverityWarning, Subject: subject, State: asks.StateRaised,
+	return oc.Condition{Key: key, Severity: occ.SeverityWarning, Subject: subject, State: occ.StateRaised,
 		Summary: headline, Headline: headline, Needs: needs,
-		Explanation: asks.NeedsYou + needs + ". The backup before applying " + module + " at " + short(fp) + " on " + node + " failed: " + words + "."}
+		Explanation: occ.NeedsYou + needs + ". The backup before applying " + module + " at " + short(fp) + " on " + node + " failed: " + words + "."}
 }

modules/mesh-delivery-assigner/internal/assign/asks_test.go

@@ -1,12 +1,16 @@
 package assign
 
 import (
+	"fmt"
+	"slices"
 	"strings"
 	"testing"
 	"time"
 
-	"git.novox.be/novox/mesh-sdk/go/asks"
+	occ "git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient"
+	oc "git.novox.be/novox/mesh-contracts/go/seats/operatorchannel"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/health"
 )
 
 // 1297/B9 (the assigner's half): the ask about a held fingerprint is a valid ask of the router and of mesh-sdk's layout at
@@ -18,27 +22,42 @@ func TestTheHoldAskIsValid(t *testing.T) {
 	}
 	now := time.Now()
 	a := HoldAsk(key, "mail", fNew, "ace", "health failed, phase running: connection refused", 0, now)
-	if err := a.Ask.Check(now); err != nil {
+	if err := occ.Check(mustAsk(t, a), now); err != nil {
 		t.Errorf("the router refuses the ask: %v", err)
 	}
-	if _, err := delivery.EncodeAssignerAsk(key, a); err != nil {
+	if _, err := EncodeAsk(key, a); err != nil {
 		t.Errorf("the ask cannot be written: %v", err)
 	}
 	// 1906/H3: the ask names the machine whose check failed and the hold's words.
-	if !strings.Contains(a.Ask.Explanation, "on ace") || !strings.Contains(a.Ask.Explanation, "connection refused") {
-		t.Errorf("the ask does not name the node and the hold's words: %q", a.Ask.Explanation)
+	if !strings.Contains(mustAsk(t, a).Explanation, "on ace") || !strings.Contains(mustAsk(t, a).Explanation, "connection refused") {
+		t.Errorf("the ask does not name the node and the hold's words: %q", mustAsk(t, a).Explanation)
 	}
 	// 1906/H2: an ask written again after a lift is another asking, under an id of its own.
 	again := HoldAsk(key, "mail", fNew, "ace", "x", 7, now)
-	if again.Asking != 7 || again.Ask.ID != delivery.AskingID(key, 7) || again.Ask.ID == a.Ask.ID {
-		t.Errorf("the asking after a lift = %d %s", again.Asking, again.Ask.ID)
+	if again.Asking != 7 || mustAsk(t, again).ID != delivery.AskingID(key, 7) || mustAsk(t, again).ID == mustAsk(t, a).ID {
+		t.Errorf("the asking after a lift = %d %s", again.Asking, mustAsk(t, again).ID)
 	}
-	if _, err := delivery.EncodeAssignerAsk(key, again); err != nil {
+	if _, err := EncodeAsk(key, again); err != nil {
 		t.Errorf("the ask asked again cannot be written: %v", err)
 	}
 	if _, err := delivery.ViewAnswerKey(key); err != nil {
 		t.Errorf("the view may not answer it: %v", err)
 	}
+	// The join (A1d ruling 1): mesh-sdk no longer refuses another id, no option or no ask in an assigner's ask; EncodeAsk does.
+	t.Run("EncodeAsk refuses what mesh-sdk no longer does", func(t *testing.T) {
+		good := HoldAsk(key, "mail", fNew, "ace", "x", 0, time.Unix(100, 0))
+		other := good
+		other.Asking = 3 // its id is the asking 0's
+		empty := good
+		ask := mustAsk(t, good)
+		ask.Options = nil
+		empty.Ask = assignerAsk(0, ask).Ask
+		for name, a := range map[string]delivery.AssignerAsk{"another id": other, "no option": empty, "no ask": {}} {
+			if _, err := EncodeAsk(key, a); err == nil {
+				t.Errorf("%s: written", name)
+			}
+		}
+	})
 }
 
 // 1906/D3 (ADR 0539 §19): the ask about a data module held on a node is a valid ask of the router and of mesh-sdk's layout at
@@ -50,53 +69,102 @@ func TestTheRestoreAskIsValid(t *testing.T) {
 	}
 	now := time.Now()
 	a := RestoreAsk(key, "ace", "mail", fNew, "connection refused", now)
-	if err := a.Ask.Check(now); err != nil {
+	if err := occ.Check(mustAsk(t, a), now); err != nil {
 		t.Errorf("the router refuses the ask: %v", err)
 	}
-	if _, err := delivery.EncodeAssignerAsk(key, a); err != nil {
+	if _, err := EncodeAsk(key, a); err != nil {
 		t.Errorf("the ask cannot be written: %v", err)
 	}
 	if _, err := delivery.ViewAnswerKey(key); err != nil {
 		t.Errorf("the view may not answer it: %v", err)
 	}
 	var ids []string
-	for _, o := range a.Ask.Options {
+	for _, o := range mustAsk(t, a).Options {
 		ids = append(ids, o.ID)
 	}
 	if len(ids) != 2 || ids[0] != OptionRestore || ids[1] != OptionLeaveStopped {
 		t.Errorf("options = %v", ids)
 	}
-	if !strings.Contains(a.Ask.Explanation, "connection refused") || !strings.Contains(a.Ask.Explanation, "ace") {
-		t.Errorf("the ask does not name the node and the check's words: %q", a.Ask.Explanation)
+	if !strings.Contains(mustAsk(t, a).Explanation, "connection refused") || !strings.Contains(mustAsk(t, a).Explanation, "ace") {
+		t.Errorf("the ask does not name the node and the check's words: %q", mustAsk(t, a).Explanation)
 	}
 }
 
 // 1906/D3: the condition for a held fingerprint names the module, the node and the check's words, under the assigner's own
 // name (ADR 0437 clause 9), and is cleared under the same key.
-func TestTheHeldConditionNamesModuleNodeAndWords(t *testing.T) {
+func TestTheAssignersConditions(t *testing.T) {
+	t.Run("the held condition names module, node and words", heldConditionNamesModuleNodeAndWords)
+	t.Run("a lifted hold clears its condition saying why", liftedHoldClearsItsConditionSayingWhy)
+	t.Run("1952/WM6: each said condition is a finding, its clear deletes it, said straight only with no findings bucket", saidConditionsAreFindings)
+}
+
+func heldConditionNamesModuleNodeAndWords(t *testing.T) {
 	c := HeldCondition("mail", fNew, "ace", "connection refused", true, true)
-	if _, err := asks.EncodeCondition(c); err != nil {
+	if _, err := occ.EncodeCondition(c); err != nil {
 		t.Fatalf("the condition is refused: %v", err)
 	}
-	if c.State != asks.StateRaised || c.Subject.ID != "mail" || c.Subject.Machine != "ace" || !strings.Contains(c.Explanation, "connection refused") || !strings.Contains(c.Key, "mail") {
+	if c.State != occ.StateRaised || c.Subject.ID != "mail" || c.Subject.Machine != "ace" || !strings.Contains(c.Explanation, "connection refused") || !strings.Contains(c.Key, "mail") {
 		t.Errorf("condition = %+v", c)
 	}
-	if got := HeldCondition("mail", fNew, "", "", false, false); got.State != asks.StateCleared || got.Key != c.Key {
+	if got := HeldCondition("mail", fNew, "", "", false, false); got.State != occ.StateCleared || got.Key != c.Key {
 		t.Errorf("cleared = %+v", got)
 	}
 }
 
 // 1906/H2: a hold lifted by itself clears the held condition under its key, saying why.
-func TestALiftedHoldClearsItsConditionSayingWhy(t *testing.T) {
+func liftedHoldClearsItsConditionSayingWhy(t *testing.T) {
 	c := LiftedCondition("mail", fNew)
-	if _, err := asks.EncodeCondition(c); err != nil {
+	if _, err := occ.EncodeCondition(c); err != nil {
 		t.Fatalf("the condition is refused: %v", err)
 	}
-	if c.State != asks.StateCleared || c.Key != HeldCondition("mail", fNew, "ace", "x", true, false).Key || !strings.Contains(c.Resolved, "lifted its hold by itself") {
+	if c.State != occ.StateCleared || c.Key != HeldCondition("mail", fNew, "ace", "x", true, false).Key || !strings.Contains(c.Resolved, "lifted its hold by itself") {
 		t.Errorf("condition = %+v", c)
 	}
 }
 
+// 1952/WM6 (ADR 0564 §2, issue 1952 note 16): every condition the assigner says is a finding in its own bucket, under
+// `<scope>.<id>.<kind>`, written at the raise and deleted at the clear, and only as a finding: the keeper is the one
+// source since the controller's end (novox/hq ADR 0590 §3, issue 1126 B8). Said straight to the router only where the
+// findings bucket cannot be written to at all.
+func saidConditionsAreFindings(t *testing.T) {
+	at := time.Date(2026, 10, 29, 21, 0, 0, 0, time.UTC)
+	for _, c := range []struct {
+		raised, cleared oc.Condition
+		key             string
+	}{
+		{HeldCondition("mail", fNew, "ace", "refused", true, true), LiftedCondition("mail", fNew), "module.mail." + strings.TrimPrefix(fNew, delivery.SourcePrefix2) + ".held"},
+		{NodeFailedCondition("ace", "mail", fNew, NodeFailure{Words: "x", Others: []string{"g14"}}, true), NodeFailedCondition("ace", "mail", fNew, NodeFailure{}, false), "module.ace.mail.failed-alone"},
+		{NeitherCondition("ace", "mail", Holding{Rule: 3, Words: "w"}, true), NeitherCondition("ace", "mail", Holding{}, false), "module.ace.mail.neither"},
+		{SeatWaitsCondition([]string{"placement"}), SeatWaitsCondition(nil), "module.mesh-delivery-assigner.seat-states"},
+		{BackupCondition("ace", "mail", fNew, "disk full", true), BackupCondition("ace", "mail", fNew, "", false), "module.ace.mail." + strings.TrimPrefix(fNew, delivery.SourcePrefix2) + ".backup"},
+	} {
+		puts, deletes, said := map[string]health.Finding{}, []string{}, 0
+		f := Findings{Put: func(k string, v []byte) error {
+			got, err := health.DecodeFinding(v)
+			puts[k] = got
+			return err
+		}, Delete: func(k string) error { deletes = append(deletes, k); return nil }, Now: func() time.Time { return at }}
+		say := f.Say(func(oc.Condition) error { said++; return nil })
+		if err := say(c.raised); err != nil {
+			t.Fatalf("%s: %v", c.key, err)
+		}
+		got, ok := puts[c.key]
+		if !ok || got.Severity != health.Severity(c.raised.Severity) || got.Headline != c.raised.Headline || got.Observer != delivery.AssignerModule ||
+			got.Subject.Machine != c.raised.Subject.Machine || said != 0 {
+			t.Fatalf("%s: finding %+v (written %v), said %d", c.key, got, puts, said)
+		}
+		if err := say(c.cleared); err != nil || !slices.Equal(deletes, []string{c.key}) || said != 0 {
+			t.Fatalf("%s: deleted %v, said %d (%v)", c.key, deletes, said, err)
+		}
+		if err := (Findings{}).Say(func(oc.Condition) error { said++; return nil })(c.raised); err != nil || said != 1 {
+			t.Fatalf("%s: with no findings bucket said %d (%v), want straight once", c.key, said, err)
+		}
+	}
+	if _, _, _, err := FindingOf(oc.Condition{Key: "another.x", State: occ.StateRaised}, at); err == nil {
+		t.Error("a condition not the assigner's is a finding")
+	}
+}
+
 // 1906/D4: the record ask and the backup ask are valid asks of the router and of mesh-sdk's layout at their keys, answerable in
 // the view, and name the move and the node.
 func TestTheRecordAndBackupAsksAreValid(t *testing.T) {
@@ -113,24 +181,24 @@ func TestTheRecordAndBackupAsksAreValid(t *testing.T) {
 	dgst := "sha256:" + strings.Repeat("b", 64)
 	b := BackupAsk(bkey, "ace", "mail", fNew, dgst, "no space left", 0, now)
 	for key, a := range map[string]delivery.AssignerAsk{rkey: r, bkey: b} {
-		if err := a.Ask.Check(now); err != nil {
+		if err := occ.Check(mustAsk(t, a), now); err != nil {
 			t.Errorf("%s: the router refuses the ask: %v", key, err)
 		}
-		if _, err := delivery.EncodeAssignerAsk(key, a); err != nil {
+		if _, err := EncodeAsk(key, a); err != nil {
 			t.Errorf("%s: cannot be written: %v", key, err)
 		}
 		if _, err := delivery.ViewAnswerKey(key); err != nil {
 			t.Errorf("%s: the view may not answer it: %v", key, err)
 		}
 	}
-	if !strings.Contains(r.Ask.Explanation, "gone") || r.Ask.Options[0].ID != OptionYes {
-		t.Errorf("the record ask = %+v", r.Ask)
+	if !strings.Contains(mustAsk(t, r).Explanation, "gone") || mustAsk(t, r).Options[0].ID != OptionYes {
+		t.Errorf("the record ask = %+v", mustAsk(t, r))
 	}
-	if !strings.Contains(b.Ask.Explanation, "no space left") || b.Ask.Options[0].ID != delivery.BackupAgain || b.Ask.Options[1].ID != delivery.BackupSkip {
-		t.Errorf("the backup ask = %+v", b.Ask)
+	if !strings.Contains(mustAsk(t, b).Explanation, "no space left") || mustAsk(t, b).Options[0].ID != delivery.BackupAgain || mustAsk(t, b).Options[1].ID != delivery.BackupSkip {
+		t.Errorf("the backup ask = %+v", mustAsk(t, b))
 	}
 	// the id binds the ask to the composition and to its number (review round 1, items 3 and 4)
-	if again := BackupAsk(bkey, "ace", "mail", fNew, dgst, "x", NextBackupAsking(0), now); again.Ask.ID == b.Ask.ID {
+	if again := BackupAsk(bkey, "ace", "mail", fNew, dgst, "x", NextBackupAsking(0), now); mustAsk(t, again).ID == mustAsk(t, b).ID {
 		t.Errorf("asked again under the same id")
 	}
 	if NextBackupAsking(-1) != 0 || NextBackupAsking(0) != 2 || NextBackupAsking(2) != 3 {
@@ -143,7 +211,7 @@ func TestTheRecordAndBackupAsksAreValid(t *testing.T) {
 		t.Errorf("two answers of the same option are one want value")
 	}
 	c := BackupCondition("ace", "mail", fNew, "no space left", true)
-	if _, err := asks.EncodeCondition(c); err != nil {
+	if _, err := occ.EncodeCondition(c); err != nil {
 		t.Errorf("the backup condition is refused: %v", err)
 	}
 	// ADR 0546 clauses 7 and 8: a put's ask is valid at the record ask's key; for the bus its yes approves and binds the act,
@@ -155,32 +223,39 @@ func TestTheRecordAndBackupAsksAreValid(t *testing.T) {
 		if err != nil {
 			t.Fatalf("bus %v: %v", bus, err)
 		}
-		if err := a.Ask.Check(now); err != nil {
+		if err := occ.Check(mustAsk(t, a), now); err != nil {
 			t.Errorf("bus %v: the router refuses the put's ask: %v", bus, err)
 		}
-		if _, err := delivery.EncodeAssignerAsk(rkey, a); err != nil {
+		if _, err := EncodeAsk(rkey, a); err != nil {
 			t.Errorf("bus %v: the put's ask cannot be written: %v", bus, err)
 		}
-		viewed := delivery.ViewAnswerFits(delivery.ViewAnswer{Asking: a.Ask.ID, Option: OptionYes}, a)
-		yes := a.Ask.Options[0]
+		viewed := delivery.ViewAnswerFits(delivery.ViewAnswer{Asking: mustAsk(t, a).ID, Option: OptionYes}, rkey, a)
+		yes := mustAsk(t, a).Options[0]
+		// mesh-sdk gives no refusal by level any more: the teller refuses an option a view cannot answer (its level is not
+		// acknowledge), as it did through the sdk before.
+		if viewed == nil {
+			if o, ok := occ.OptionOf(mustAsk(t, a), OptionYes); ok && o.Level != "" && o.Level != occ.Acknowledge {
+				viewed = fmt.Errorf("only a channel that proves who answered takes the option %s", o.ID)
+			}
+		}
 		switch {
-		case !strings.Contains(a.Ask.Explanation, "the bus's user list"):
-			t.Errorf("bus %v: the put's ask does not say why: %s", bus, a.Ask.Explanation)
-		case bus && (yes.Level != asks.Approve || yes.Binds == "" || viewed == nil || a.Ask.Expires.After(now.Add(asks.ApproveLasts))):
-			t.Errorf("bus: the yes is %+v, the view's answer %v, expiring %s", yes, viewed, a.Ask.Expires)
-		case !bus && (yes.Level != asks.Acknowledge || viewed != nil):
+		case !strings.Contains(mustAsk(t, a).Explanation, "the bus's user list"):
+			t.Errorf("bus %v: the put's ask does not say why: %s", bus, mustAsk(t, a).Explanation)
+		case bus && (yes.Level != occ.Approve || yes.Binds == "" || viewed == nil || expiresAt(t, a).After(now.Add(occ.ApproveLasts))):
+			t.Errorf("bus: the yes is %+v, the view's answer %v, expiring %s", yes, viewed, expiresAt(t, a))
+		case !bus && (yes.Level != occ.Acknowledge || viewed != nil):
 			t.Errorf("a recorded module: the yes is %+v, the view's answer %v", yes, viewed)
 		}
 		later := put
 		later.At = now.Add(time.Minute)
 		b, _ := PutAsk(rkey, "ace", "mail", later, d, bus, now)
-		if b.Ask.ID == a.Ask.ID || b.Asking != PutAsking(later) {
-			t.Errorf("bus %v: a later put's ask is asking %d under id %q, the earlier's %q", bus, b.Asking, b.Ask.ID, a.Ask.ID)
+		if mustAsk(t, b).ID == mustAsk(t, a).ID || b.Asking != PutAsking(later) {
+			t.Errorf("bus %v: a later put's ask is asking %d under id %q, the earlier's %q", bus, b.Asking, mustAsk(t, b).ID, mustAsk(t, a).ID)
 		}
-		if err := yes.Performs(PutAct("ace", "mail", fNew, dgst)); err != nil {
+		if err := occ.Performs(yes, PutAct("ace", "mail", fNew, dgst)); err != nil {
 			t.Errorf("bus %v: the yes does not perform the act it bound: %v", bus, err)
 		}
-		if err := yes.Performs(PutAct("ace", "mail", fNew, dig(fOld))); bus && err == nil {
+		if err := occ.Performs(yes, PutAct("ace", "mail", fNew, dig(fOld))); bus && err == nil {
 			t.Errorf("bus: the yes performs another composition's act")
 		}
 	}
@@ -190,14 +265,29 @@ func TestTheRecordAndBackupAsksAreValid(t *testing.T) {
 // under the assigner's own name keyed by node and module, and is cleared under the same key.
 func TestTheNeitherConditionNamesModuleNodeAndRule(t *testing.T) {
 	c := NeitherCondition("g14", "i3status-rust", Holding{Rule: delivery.RuleProviders, Words: "no provider of x11-display runs healthy on g14 or at its canary"}, true)
-	if _, err := asks.EncodeCondition(c); err != nil {
+	if _, err := occ.EncodeCondition(c); err != nil {
 		t.Fatalf("the condition is refused: %v", err)
 	}
-	if c.State != asks.StateRaised || c.Severity != asks.SeverityUrgent || c.Subject.ID != "i3status-rust" || c.Subject.Machine != "g14" ||
+	if c.State != occ.StateRaised || c.Severity != occ.SeverityUrgent || c.Subject.ID != "i3status-rust" || c.Subject.Machine != "g14" ||
 		!strings.Contains(c.Explanation, "x11-display") || !strings.Contains(c.Explanation, "rule 5") || c.Key != "mesh-delivery-assigner.neither.g14.i3status-rust" {
 		t.Errorf("condition = %+v", c)
 	}
-	if got := NeitherCondition("g14", "i3status-rust", Holding{}, false); got.State != asks.StateCleared || got.Key != c.Key {
+	if got := NeitherCondition("g14", "i3status-rust", Holding{}, false); got.State != occ.StateCleared || got.Key != c.Key {
 		t.Errorf("cleared = %+v", got)
 	}
 }
+
+// mustAsk is the router's ask an asks-state value carries.
+func mustAsk(t *testing.T, a delivery.AssignerAsk) oc.Ask {
+	t.Helper()
+	ask, err := AskOf(a)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return ask
+}
+
+func expiresAt(t *testing.T, a delivery.AssignerAsk) time.Time {
+	t.Helper()
+	return ExpiresAt(mustAsk(t, a))
+}

modules/mesh-delivery-assigner/internal/assign/compose.go

@@ -1,302 +0,0 @@
-// Package assign is the assigner's judgement, as functions over what it read from the bus: the composition check of a
-// change (novox/hq ADR 0446 clauses 1 to 5, ADR 0528 clause 5, issue 1297), the six rules of what each node should
-// run (ADR 0429 §6, ADR 0528 clause 3) and the comparison with what the controller sends (ADR 0528 clause 4). It reads
-// and writes nothing itself: the program hands it what it watched and writes what it answers.
-package assign
-
-import (
-	"fmt"
-	"slices"
-	"sort"
-	"strings"
-	"time"
-
-	"git.novox.be/novox/mesh-sdk/go/catalogue"
-	"git.novox.be/novox/mesh-sdk/go/compose"
-	"git.novox.be/novox/mesh-sdk/go/delivery"
-)
-
-// SDKRepository is the repository of mesh-sdk: a group with a member there changes the composition itself.
-const SDKRepository = "novox/mesh-sdk"
-
-// NotJudged names, in a composition's warnings, the failures of ADR 0446 clause 1 the assigner cannot judge from the
-// bus, because what they need is only in the controller's facts snapshot, which is not on the bus yet (issue 1461;
-// the design limit of R4g, issue 1297): said on every verdict, never passed silently.
-const NotJudged = "not judged until the facts snapshot is on the bus (issue 1461): a consumer left out of a grant, a " +
-	"credential left bound elsewhere, a stored setting the changed definition cannot keep, and a new module the " +
-	"node-engine's validator would refuse"
-
-// Mesh is the mesh as the trunk holds it: every module's manifest by name, the manifests that cannot be read with
-// why, and each node's open assignments.
-type Mesh struct {
-	Manifests  map[string]catalogue.Manifest
-	Unreadable map[string]string
-	Assigned   map[string][]string
-	// Digests is every trunk module's manifest digest in the indexer's manifests bucket, readable or not: what a
-	// composer at another mesh-sdk reads (issue 1622).
-	Digests map[string]string
-	// Input is the rest of the mesh as the nodes compose from it, filled by mesh-sdk's frombus from the catalogue's
-	// placement and the nodes' records (novox/hq ADR 0547 §2, ADR 0549 §3, issue 1126), so the check and the nodes share
-	// one composer's input; nil before any placement is read, when the nodes and their assignments alone are composed.
-	Input *compose.Input
-	// InputUnread says why that input could not be read from the bus, when it could not: the check then composes the
-	// nodes and their assignments alone, and says so in its warnings.
-	InputUnread string
-}
-
-// Change is a group's change as the indexer's candidate holds it: the manifest of every module it moves or adds, those
-// it cannot read and why, the modules it removes, every module defined twice with where, the heads of a mesh-sdk
-// member (empty when none), and how many modules it rebuilds.
-type Change struct {
-	Group, Heads string
-	Manifests    map[string]catalogue.Manifest
-	Unreadable   map[string]string
-	Removed      []string
-	Twice        map[string][]string
-	SDKHead      string
-	Rebuilt      int
-	// Digests is the manifest digest of every module the change moves or adds, readable by the assigner or not, and
-	// Members the head of each member by repository: what a composer at the group's mesh-sdk reads (issues 1622, 1623).
-	Digests map[string]string
-	Members map[string]string
-}
-
-// Touched is the machines a change touches (ADR 0446 clause 3): those running a module the change moves, adds or
-// removes, those running a consumer of a provision such a module provides (before or after), and those running a
-// provider of a provision such a module requires after the change. A module the change adds that is assigned nowhere
-// touches no machine. A change of placement is no change of a repository (ADR 0567 §4): the seat
-// mesh-placement judges it.
-func Touched(m Mesh, c Change) []string {
-	moved := map[string]bool{}
-	for name := range c.Manifests {
-		moved[name] = true
-	}
-	for name := range c.Unreadable {
-		moved[name] = true
-	}
-	for _, name := range c.Removed {
-		moved[name] = true
-	}
-	provided, required := map[string]bool{}, map[string]bool{}
-	for name := range moved {
-		for _, man := range []catalogue.Manifest{m.Manifests[name], c.Manifests[name]} {
-			for _, o := range man.Provides {
-				provided[o.Name] = true
-			}
-		}
-		for _, r := range c.Manifests[name].Requires {
-			required[r] = true
-		}
-	}
-	var out []string
-	for node, modules := range m.Assigned {
-		for _, mod := range modules {
-			man := m.Manifests[mod]
-			if moved[mod] || slices.ContainsFunc(man.Requires, func(r string) bool { return provided[r] }) ||
-				slices.ContainsFunc(man.Provides, func(o catalogue.Offer) bool { return required[o.Name] }) {
-				out = append(out, node)
-				break
-			}
-		}
-	}
-	sort.Strings(out)
-	return out
-}
-
-// input is the composition's input for the mesh's catalogue and assignments: the nodes by name with what is assigned
-// to them, and every seat the assigned modules claim as held there. What the bus does not carry (places on the
-// private network, settings, credentials, licences) is left empty, so a trunk composition and a change's are made
-// with the same gaps and compared (ADR 0446 clause 1: what was already broken is said and fails nothing).
-func input(catalog map[string]catalogue.Manifest, assigned map[string][]string) compose.Input {
-	in := compose.Input{Catalogue: catalog}
-	nodes := make([]string, 0, len(assigned))
-	for n := range assigned {
-		nodes = append(nodes, n)
-	}
-	sort.Strings(nodes)
-	for _, n := range nodes {
-		in.Nodes = append(in.Nodes, compose.Node{Name: n, Assigned: slices.Clone(assigned[n])})
-		for _, mod := range assigned[n] {
-			for _, cl := range catalog[mod].Claims {
-				scope := cl.Scope
-				if seat, ok := catalogue.SeatNamed(cl.Name); ok && scope == "" {
-					scope = seat.Scope
-				}
-				in.Holdings = append(in.Holdings, catalogue.Held{Claim: cl.Name, Scope: scope, Node: n, Module: mod})
-			}
-		}
-	}
-	return in
-}
-
-// Compose is the composition check of change c over the mesh m, composed with the mesh-sdk version sdk: every touched
-// machine resolved as the trunk holds it and as the change leaves it. It fails on a manifest of the change that cannot
-// be read, a module a machine runs that the change removes, a module defined twice, and a machine that resolves on the
-// trunk and not with the change; a machine that does not resolve on either is said and fails nothing. It warns past
-// CompositionRebuildWarning modules rebuilt, says what it does not judge (NotJudged), and for a group with a mesh-sdk
-// member says it composed with its own mesh-sdk, not the member's head (issue 1621). took is how long it took.
-func Compose(m Mesh, c Change, sdk string, took time.Duration) delivery.CompositionVerdict {
-	v := delivery.CompositionVerdict{Group: c.Group, Heads: c.Heads, SDK: sdk, Took: took.Milliseconds()}
-	var fails []string
-	failAt := func(machine, words string) {
-		if v.Machine == "" && machine != "" {
-			v.Machine = machine
-		}
-		fails = append(fails, words)
-	}
-	for _, name := range sortedKeys(c.Unreadable) {
-		failAt("", fmt.Sprintf("the manifest of %s cannot be read: %s", name, c.Unreadable[name]))
-	}
-	for _, name := range sortedKeys(c.Twice) {
-		failAt("", fmt.Sprintf("%s is defined twice, in %s", name, strings.Join(c.Twice[name], " and ")))
-	}
-	machines := Touched(m, c)
-	v.Machines = machines
-	for _, node := range machines {
-		for _, name := range c.Removed {
-			if slices.Contains(m.Assigned[node], name) {
-				failAt(node, fmt.Sprintf("%s runs %s, which the change removes from its source", node, name))
-			}
-		}
-	}
-	trunk := input(m.Manifests, m.Assigned)
-	changed := map[string]catalogue.Manifest{}
-	for name, man := range m.Manifests {
-		changed[name] = man
-	}
-	for name, man := range c.Manifests {
-		changed[name] = man
-	}
-	for _, name := range c.Removed {
-		delete(changed, name)
-	}
-	after := input(changed, m.Assigned)
-	for _, node := range machines {
-		_, before := compose.Resolve(trunk, node)
-		_, now := compose.Resolve(after, node)
-		switch {
-		case now == nil:
-		case before != nil:
-			v.Warnings = append(v.Warnings, fmt.Sprintf("%s does not compose on the trunk either, so the change is not blamed: %v", node, before))
-		default:
-			failAt(node, fmt.Sprintf("%s composes on the trunk and not with the change: %v", node, now))
-		}
-	}
-	if c.SDKHead != "" {
-		v.Warnings = append(v.Warnings, fmt.Sprintf("composed with the assigner's own mesh-sdk %s, not the group's mesh-sdk head %s, "+
-			"and a field the running controller cannot read is not judged (issues 1621, 1622, 1623)", sdk, c.SDKHead))
-	}
-	return finish(v, m, c, machines, fails)
-}
-
-// finish adds what every composition says beside its own judgement (more modules rebuilt than CompositionRebuildWarning,
-// what is not judged, the machines not composed, a change that touches none) and its state from fails.
-func finish(v delivery.CompositionVerdict, m Mesh, c Change, machines []string, fails []string) delivery.CompositionVerdict {
-	if c.Rebuilt > delivery.CompositionRebuildWarning {
-		v.Warnings = append(v.Warnings, fmt.Sprintf("the merge rebuilds %d modules, more than %d", c.Rebuilt, delivery.CompositionRebuildWarning))
-	}
-	v.Warnings = append(v.Warnings, NotJudged)
-	if could := CouldRun(m, c, machines); len(could) > 0 {
-		v.Warnings = append(v.Warnings, "not judged until the facts snapshot is on the bus (issue 1461, ADR 0537 clause 1): "+
-			"the machines that could run a moved or added module and are not assigned it: "+strings.Join(could, ", "))
-	}
-	if grants := GrantsAlone(m, c, machines); len(grants) > 0 {
-		v.Warnings = append(v.Warnings, "not judged until the facts snapshot is on the bus (issue 1461, ADR 0537 clause 1): "+
-			"the machines whose grants alone the change alters: "+strings.Join(grants, ", "))
-	}
-	if len(machines) == 0 {
-		v.Warnings = append(v.Warnings, "the change touches no machine: no module it moves is assigned anywhere")
-	}
-	if len(fails) > 0 {
-		v.State, v.Words = delivery.CompositionFail, strings.Join(fails, "; ")
-		return v
-	}
-	v.State = delivery.CompositionPass
-	return v
-}
-
-// CouldRun is, by name, every machine of the mesh not composed that is not assigned a module the change moves or adds
-// (ADR 0537 clause 1): which of them could run it, the bus does not say (capabilities, settings and places are only in
-// the facts snapshot), so each is named as not judged.
-func CouldRun(m Mesh, c Change, composed []string) []string {
-	var out []string
-	for node, modules := range m.Assigned {
-		if slices.Contains(composed, node) {
-			continue
-		}
-		for name := range c.Manifests {
-			if !slices.Contains(modules, name) {
-				out = append(out, node)
-				break
-			}
-		}
-	}
-	sort.Strings(out)
-	return out
-}
-
-// grantsOf is what of a manifest makes grants: its bus declarations and the provisions it requires and offers.
-func grantsOf(man catalogue.Manifest) string {
-	var offers []string
-	for _, o := range man.Provides {
-		offers = append(offers, o.Name)
-	}
-	return fmt.Sprint(man.Requires, offers, man.Reads, man.State, man.Emits, man.Consumes, man.Invokes, man.Claims, man.Grants)
-}
-
-// GrantsAlone is, by name, every machine not composed whose grants alone the change alters (ADR 0537 clause 1): for a
-// moved module whose grants differ from the trunk's, the machines assigned the bus's holder (whose user list carries
-// every module's bus grants) and those assigned a provider of a provision it requires, before or after.
-func GrantsAlone(m Mesh, c Change, composed []string) []string {
-	provisions := map[string]bool{}
-	altered := false
-	for name, man := range c.Manifests {
-		before, had := m.Manifests[name]
-		if had && grantsOf(before) == grantsOf(man) {
-			continue
-		}
-		altered = true
-		for _, r := range append(slices.Clone(man.Requires), before.Requires...) {
-			provisions[r] = true
-		}
-	}
-	if !altered {
-		return nil
-	}
-	var out []string
-	for node, modules := range m.Assigned {
-		if slices.Contains(composed, node) {
-			continue
-		}
-		for _, mod := range modules {
-			man := m.Manifests[mod]
-			if man.ClaimsSeat("mesh-broker") || slices.ContainsFunc(man.Provides, func(o catalogue.Offer) bool { return provisions[o.Name] }) {
-				out = append(out, node)
-				break
-			}
-		}
-	}
-	sort.Strings(out)
-	return out
-}
-
-// withOverlay is base with every manifest of over laid over it, a copy.
-func withOverlay(base, over map[string]catalogue.Manifest) map[string]catalogue.Manifest {
-	out := make(map[string]catalogue.Manifest, len(base)+len(over))
-	for name, man := range base {
-		out[name] = man
-	}
-	for name, man := range over {
-		out[name] = man
-	}
-	return out
-}
-
-func sortedKeys[V any](m map[string]V) []string {
-	out := make([]string, 0, len(m))
-	for k := range m {
-		out = append(out, k)
-	}
-	sort.Strings(out)
-	return out
-}

modules/mesh-delivery-assigner/internal/assign/compose_test.go

@@ -1,141 +0,0 @@
-package assign
-
-import (
-	"slices"
-	"strings"
-	"testing"
-
-	"git.novox.be/novox/mesh-sdk/go/catalogue"
-	"git.novox.be/novox/mesh-sdk/go/delivery"
-)
-
-func meshOf() Mesh {
-	return Mesh{
-		Manifests: map[string]catalogue.Manifest{
-			"mail":  {Module: "mail", Version: "1", Requires: []string{"database"}},
-			"store": {Module: "store", Version: "1", Provides: []catalogue.Offer{{Name: "database"}}},
-			"web":   {Module: "web", Version: "1"},
-		},
-		Assigned: map[string][]string{"ace": {"mail", "store"}, "g14": {"web"}},
-	}
-}
-
-func hasWarning(v delivery.CompositionVerdict, part string) bool {
-	return slices.ContainsFunc(v.Warnings, func(w string) bool { return strings.Contains(w, part) })
-}
-
-// 1297/AC1 (its unit half): a change touching one module on one machine composes that machine alone, passes, names
-// the machine and the mesh-sdk it composed with, and says what it did not judge.
-func TestAChangeOfOneModuleComposesItsMachine(t *testing.T) {
-	c := Change{Group: "g", Heads: "0123456789ab", Manifests: map[string]catalogue.Manifest{"web": {Module: "web", Version: "2"}}}
-	v := Compose(meshOf(), c, "v0.1.14-x", 0)
-	if v.State != delivery.CompositionPass || !slices.Equal(v.Machines, []string{"g14"}) || v.SDK != "v0.1.14-x" {
-		t.Fatalf("composition = %+v, want a pass on g14 alone", v)
-	}
-	if !hasWarning(v, "issue 1461") {
-		t.Errorf("the verdict does not say what it did not judge: %v", v.Warnings)
-	}
-	if _, err := delivery.EncodeCompositionVerdict(v); err != nil {
-		t.Errorf("the verdict cannot be written: %v", err)
-	}
-}
-
-// 1297/AC2: a change that removes a module a machine runs fails, naming the machine and the module.
-func TestRemovingAModuleAMachineRunsFails(t *testing.T) {
-	c := Change{Group: "g", Heads: "0123456789ab", Removed: []string{"web"}}
-	v := Compose(meshOf(), c, "sdk", 0)
-	if v.State != delivery.CompositionFail || v.Machine != "g14" || !strings.Contains(v.Words, "g14 runs web") {
-		t.Fatalf("composition = %+v, want a fail naming g14 and web", v)
-	}
-}
-
-// 1297/B3c: a machine that composes on the trunk and not with the change fails it, naming the machine and why; the
-// consumer's machine is touched when its provider changes.
-func TestAMachineTheChangeBreaksFails(t *testing.T) {
-	c := Change{Group: "g", Heads: "0123456789ab", Manifests: map[string]catalogue.Manifest{"store": {Module: "store", Version: "2"}}}
-	v := Compose(meshOf(), c, "sdk", 0)
-	if v.State != delivery.CompositionFail || v.Machine != "ace" || !strings.Contains(v.Words, "database") {
-		t.Fatalf("composition = %+v, want a fail on ace naming the provision nothing provides", v)
-	}
-}
-
-// 1297/B3c: what was already broken on the trunk is said and fails nothing.
-func TestWhatWasBrokenBeforeFailsNothing(t *testing.T) {
-	m := meshOf()
-	m.Manifests["store"] = catalogue.Manifest{Module: "store", Version: "1"}
-	c := Change{Group: "g", Heads: "0123456789ab", Manifests: map[string]catalogue.Manifest{"mail": {Module: "mail", Version: "2", Requires: []string{"database"}}}}
-	v := Compose(m, c, "sdk", 0)
-	if v.State != delivery.CompositionPass || !hasWarning(v, "on the trunk either") {
-		t.Fatalf("composition = %+v, want a pass saying ace was already broken", v)
-	}
-}
-
-// 1297/B3c: an unreadable manifest and a module defined twice fail; more than twelve rebuilt modules warn.
-func TestUnreadableTwiceAndWide(t *testing.T) {
-	c := Change{Group: "g", Heads: "0123456789ab", Unreadable: map[string]string{"web": "unknown field \"scope\""}, Rebuilt: 13}
-	v := Compose(meshOf(), c, "sdk", 0)
-	if v.State != delivery.CompositionFail || !strings.Contains(v.Words, "web cannot be read") || !hasWarning(v, "rebuilds 13 modules") {
-		t.Fatalf("composition = %+v", v)
-	}
-	c = Change{Group: "g", Heads: "0123456789ab", Twice: map[string][]string{"web": {"novox/a", "novox/b"}}, Rebuilt: 12}
-	v = Compose(meshOf(), c, "sdk", 0)
-	if v.State != delivery.CompositionFail || !strings.Contains(v.Words, "web is defined twice") || hasWarning(v, "rebuilds") {
-		t.Fatalf("composition = %+v", v)
-	}
-}
-
-// 1622's criterion as R4g delivers it: a group with a mesh-sdk member is composed with the assigner's own mesh-sdk, and
-// the verdict says so, naming the member's head it did not use; a group without one says nothing of it.
-func TestAGroupWithAnSDKMemberSaysWhichSDKComposedIt(t *testing.T) {
-	c := Change{Group: "g", Heads: "0123456789ab", Manifests: map[string]catalogue.Manifest{"web": {Module: "web", Version: "2"}}, SDKHead: "f625d98713e4"}
-	v := Compose(meshOf(), c, "v0.1.14-own", 0)
-	if !hasWarning(v, "not the group's mesh-sdk head f625d98713e4") || !hasWarning(v, "v0.1.14-own") || !hasWarning(v, "1623") {
-		t.Errorf("the verdict does not say it composed with its own mesh-sdk: %v", v.Warnings)
-	}
-	c.SDKHead = ""
-	if v := Compose(meshOf(), c, "v0.1.14-own", 0); hasWarning(v, "mesh-sdk head") {
-		t.Errorf("a group without a mesh-sdk member says it has one: %v", v.Warnings)
-	}
-}
-
-// 1297/B3a: the machines touched are those running a moved module or a consumer of what it provides; an added module
-// assigned nowhere touches none, and the verdict says so.
-func TestTouched(t *testing.T) {
-	m := meshOf()
-	if got := Touched(m, Change{Manifests: map[string]catalogue.Manifest{"store": m.Manifests["store"]}}); !slices.Equal(got, []string{"ace"}) {
-		t.Errorf("touched by store = %v", got)
-	}
-	m.Assigned["g14"] = append(m.Assigned["g14"], "mail")
-	if got := Touched(m, Change{Manifests: map[string]catalogue.Manifest{"store": m.Manifests["store"]}}); !slices.Equal(got, []string{"ace", "g14"}) {
-		t.Errorf("touched by store with a consumer on g14 = %v", got)
-	}
-	c := Change{Group: "g", Heads: "0123456789ab", Manifests: map[string]catalogue.Manifest{"new": {Module: "new", Version: "1"}}}
-	if v := Compose(m, c, "sdk", 0); len(v.Machines) != 0 || !hasWarning(v, "touches no machine") || v.State != delivery.CompositionPass {
-		t.Errorf("an added module assigned nowhere: %+v", v)
-	}
-}
-
-// ADR 0537 clause 1: every verdict names, by machine, those that could run a moved or added module and are not assigned
-// it, and those whose grants alone the change alters (the bus's machine, a provider of what the module requires), as not
-// judged; shanks, providing what web now requires, is composed and so named in neither. A change that alters no grant
-// names none of the second.
-func TestTheMachinesNotJudgedAreNamed(t *testing.T) {
-	m := meshOf()
-	m.Manifests["bus"] = catalogue.Manifest{Module: "bus", Version: "1", Claims: []catalogue.Claim{{Name: "mesh-broker", Scope: "mesh"}}}
-	m.Manifests["db"] = catalogue.Manifest{Module: "db", Version: "1", Provides: []catalogue.Offer{{Name: "cache"}}}
-	m.Assigned["novox"] = []string{"bus"}
-	m.Assigned["shanks"] = []string{"db"}
-	c := Change{Group: "g", Heads: "0123456789ab", Manifests: map[string]catalogue.Manifest{
-		"web": {Module: "web", Version: "2", Reads: []string{"mesh-controller.assignments"}, Requires: []string{"cache"}}}}
-	v := Compose(m, c, "sdk", 0)
-	if !hasWarning(v, "could run a moved or added module and are not assigned it: ace, novox") || !slices.Contains(v.Machines, "shanks") {
-		t.Errorf("the machines that could run web are not named: %v", v.Warnings)
-	}
-	if !hasWarning(v, "whose grants alone the change alters: novox") {
-		t.Errorf("the machines whose grants alone change are not named: %v", v.Warnings)
-	}
-	c.Manifests["web"] = catalogue.Manifest{Module: "web", Version: "3"}
-	if v := Compose(meshOf(), c, "sdk", 0); hasWarning(v, "grants alone") {
-		t.Errorf("a change altering no grant names machines whose grants change: %v", v.Warnings)
-	}
-}

modules/mesh-delivery-assigner/internal/assign/composer.go

@@ -1,253 +0,0 @@
-package assign
-
-import (
-	"encoding/json"
-	"fmt"
-	"slices"
-	"sort"
-	"strings"
-	"time"
-
-	"git.novox.be/novox/mesh-sdk/go/compose"
-	"git.novox.be/novox/mesh-sdk/go/composer"
-	"git.novox.be/novox/mesh-sdk/go/delivery"
-)
-
-// The cases of a group's composition at its mesh-sdk head: the trunk as it is, and the trunk with the change.
-const (
-	CaseTrunk  = "trunk"
-	CaseChange = "change"
-)
-
-// SDKDir is the directory of mesh-sdk's Go module in its repository, where the composer is built at a head; a reader's
-// composer is built at its repository's root, at the mesh-sdk its go.mod pins.
-const SDKDir = "go"
-
-// The modules whose mesh-sdk reads the manifests a plan sends (ADR 0482 clause 5): the controller composes and sends
-// them, the node-engine applies them. Each is judged at its repository.
-var ReaderModules = map[string]string{"mesh-controller": "novox/mesh-controller", "mesh-host": "novox/mesh-host"}
-
-// HeadJob is the compose job of a group with a mesh-sdk member (ADR 0482 clauses 3 and 4, issue 1622): the composer
-// built at the member's head composes the machines the change touches, as the trunk holds them and as the change leaves
-// them, every manifest named by its digest in the indexer's bucket, the seats held from the claims (the assigner's input).
-func HeadJob(m Mesh, c Change) (delivery.ComposeJob, error) {
-	trunk, change := map[string]composer.Manifest{}, map[string]composer.Manifest{}
-	for name, digest := range m.Digests {
-		trunk[name] = composer.Manifest{Digest: digest}
-		change[name] = composer.Manifest{Digest: digest}
-	}
-	for name, digest := range c.Digests {
-		change[name] = composer.Manifest{Digest: digest}
-	}
-	for _, name := range c.Removed {
-		delete(change, name)
-	}
-	in, fromClaims := plainInput(m.Assigned), true
-	if m.Input != nil {
-		// The input the nodes compose from, without its catalogue: the cases carry the manifests (issue 1126).
-		in = *m.Input
-		in.Catalogue = nil
-		fromClaims = len(in.Holdings) == 0
-	}
-	changeCase := composer.Case{Name: CaseChange, Manifests: change}
-	req := composer.Request{V: composer.Version, Input: in, Depth: composer.DepthResolve,
-		HoldingsFromClaims: fromClaims, Machines: Touched(m, c),
-		Cases: []composer.Case{{Name: CaseTrunk, Manifests: trunk}, changeCase}}
-	return job(SDKRepository, c.SDKHead, SDKDir, req, "the mesh-sdk head of "+c.Group)
-}
-
-// ReaderJob is the compose job that reads the manifests a group changes with the mesh-sdk a reader module pins at
-// commit (ADR 0482 clause 5, issue 1623): no machine is composed, every changed manifest is only read.
-func ReaderJob(c Change, module, repository, commit string) (delivery.ComposeJob, error) {
-	changed := map[string]composer.Manifest{}
-	for name, digest := range c.Digests {
-		changed[name] = composer.Manifest{Digest: digest}
-	}
-	req := composer.Request{V: composer.Version, Cases: []composer.Case{{Name: CaseChange, Manifests: changed}}}
-	return job(repository, commit, delivery.RootPath, req, module+" at "+commit)
-}
-
-func job(repository, commit, dir string, req composer.Request, reader string) (delivery.ComposeJob, error) {
-	raw, err := json.Marshal(req)
-	if err != nil {
-		return delivery.ComposeJob{}, err
-	}
-	return delivery.ComposeJob{Fetch: map[string]any{"repository": repository, "commit": commit}, Dir: dir,
-		Package: composer.Package, Request: raw, Reader: reader}, nil
-}
-
-// plainInput is the composition's input without its catalogue: the nodes by name with what is assigned to them (the
-// composer derives the seats held from the claims, as input does).
-func plainInput(assigned map[string][]string) compose.Input {
-	var in compose.Input
-	nodes := make([]string, 0, len(assigned))
-	for n := range assigned {
-		nodes = append(nodes, n)
-	}
-	sort.Strings(nodes)
-	for _, n := range nodes {
-		in.Nodes = append(in.Nodes, compose.Node{Name: n, Assigned: slices.Clone(assigned[n])})
-	}
-	return in
-}
-
-// Ran is one compose ask's end: its step's state and reason, and the composer's verdict when the step passed.
-type Ran struct {
-	State   string
-	Reason  string
-	Verdict *composer.Verdict
-}
-
-// RanOf reads a compose ask's end from its step value; a step that passed with an answer that cannot be read is a
-// failure, named.
-func RanOf(step delivery.Step) Ran {
-	r := Ran{State: step.State, Reason: step.Reason}
-	if step.State != delivery.StepPassed {
-		return r
-	}
-	var a delivery.ComposeAnswer
-	var v composer.Verdict
-	if err := json.Unmarshal(step.Result, &a); err != nil {
-		return Ran{State: delivery.StepFailed, Reason: "the compose step's answer cannot be read: " + err.Error()}
-	}
-	if err := json.Unmarshal(a.Verdict, &v); err != nil || v.V != composer.Version {
-		return Ran{State: delivery.StepFailed, Reason: fmt.Sprintf("the composer's verdict cannot be read (version %d): %v", v.V, err)}
-	}
-	r.Verdict = &v
-	return r
-}
-
-func caseOf(v *composer.Verdict, name string) (composer.CaseVerdict, bool) {
-	if v == nil {
-		return composer.CaseVerdict{}, false
-	}
-	for _, c := range v.Cases {
-		if c.Name == name {
-			return c, true
-		}
-	}
-	return composer.CaseVerdict{}, false
-}
-
-// Reader is one module whose mesh-sdk reads the group's manifests, at the commit judged: the group's member head when
-// the group holds one in its repository, else a build its node runs.
-type Reader struct {
-	Module, Commit string
-	Member         bool
-	Ran            Ran
-}
-
-// FromComposer is the composition check of a group with a mesh-sdk member, judged from the composer built at its head
-// (ADR 0482 clauses 3 to 5, issues 1622 and 1623): the same failures as Compose, read from the composer's two cases, the
-// verdict naming the mesh-sdk the composer was built with; a trunk manifest the head's mesh-sdk refuses fails too (the
-// group would deliver a reader that refuses it); and each reader that refuses a changed manifest the head reads fails
-// it, naming the module and its words, unless the reader's mesh-sdk has no composer to ask (before issue 1621), which is
-// said and judged nothing.
-func FromComposer(m Mesh, c Change, head Ran, readers []Reader, took time.Duration) delivery.CompositionVerdict {
-	v := delivery.CompositionVerdict{Group: c.Group, Heads: c.Heads, SDK: "mesh-sdk " + c.SDKHead, Took: took.Milliseconds()}
-	machines := Touched(m, c)
-	v.Machines = machines
-	var fails []string
-	if head.State != delivery.StepPassed {
-		v.Words = fmt.Sprintf("the composer at mesh-sdk %s did not run: %s %s", c.SDKHead, head.State, head.Reason)
-		v.State = delivery.CompositionFail
-		return v
-	}
-	if head.Verdict.SDK != "" {
-		v.SDK = head.Verdict.SDK
-	}
-	trunk, okT := caseOf(head.Verdict, CaseTrunk)
-	change, okC := caseOf(head.Verdict, CaseChange)
-	if !okT || !okC {
-		v.State, v.Words = delivery.CompositionFail, "the composer's verdict holds no trunk or no change case"
-		return v
-	}
-	failAt := func(machine, words string) {
-		if v.Machine == "" && machine != "" {
-			v.Machine = machine
-		}
-		fails = append(fails, words)
-	}
-	for _, name := range sortedKeys(c.Digests) {
-		if r := change.Manifests[name]; !r.Accepted {
-			failAt("", fmt.Sprintf("the manifest of %s cannot be read by mesh-sdk %s: %s", name, c.SDKHead, r.Refused))
-		}
-	}
-	for _, name := range sortedKeys(trunk.Manifests) {
-		if _, changed := c.Digests[name]; changed || slices.Contains(c.Removed, name) || trunk.Manifests[name].Accepted {
-			continue
-		}
-		if _, before := m.Unreadable[name]; before {
-			continue // already unreadable on the trunk: not the group's doing
-		}
-		failAt("", fmt.Sprintf("mesh-sdk %s refuses the trunk's manifest of %s, which the group does not change: %s", c.SDKHead, name, trunk.Manifests[name].Refused))
-	}
-	for _, name := range sortedKeys(c.Twice) {
-		failAt("", fmt.Sprintf("%s is defined twice, in %s", name, strings.Join(c.Twice[name], " and ")))
-	}
-	for _, node := range machines {
-		for _, name := range c.Removed {
-			if slices.Contains(m.Assigned[node], name) {
-				failAt(node, fmt.Sprintf("%s runs %s, which the change removes from its source", node, name))
-			}
-		}
-		before, now := trunk.Machines[node], change.Machines[node]
-		switch {
-		case now.Composes:
-		case !before.Composes:
-			v.Warnings = append(v.Warnings, fmt.Sprintf("%s does not compose on the trunk either, so the change is not blamed: %s", node, before.Reason))
-		default:
-			failAt(node, fmt.Sprintf("%s composes on the trunk and not with the change: %s", node, now.Reason))
-		}
-	}
-	readerFails, readerWarnings := judgeReaders(c, change, readers)
-	fails = append(fails, readerFails...)
-	v.Warnings = append(v.Warnings, readerWarnings...)
-	if m.InputUnread != "" {
-		v.Warnings = append(v.Warnings, "composed over the nodes and their assignments alone: the input the nodes compose from "+
-			"cannot be read from the bus ("+m.InputUnread+")")
-	}
-	return finish(v, m, c, machines, fails)
-}
-
-// NoComposer says whether a compose step failed because the mesh-sdk it was built at has no composer command (a mesh-sdk
-// from before issue 1621): Go's words for a package its module does not hold.
-func NoComposer(reason string) bool {
-	for _, words := range []string{"cannot find package", "no required module provides package", "is not in std", "cannot find module providing package", "does not contain package"} {
-		if strings.Contains(reason, words) {
-			return true
-		}
-	}
-	return false
-}
-
-func judgeReaders(c Change, head composer.CaseVerdict, readers []Reader) (fails, warnings []string) {
-	for _, r := range readers {
-		at := r.Module + " at " + r.Commit
-		if r.Member {
-			at = r.Module + "'s member head " + r.Commit
-		}
-		if r.Ran.State != delivery.StepPassed {
-			if NoComposer(r.Ran.Reason) {
-				warnings = append(warnings, fmt.Sprintf("not judged whether %s reads the group's manifests: the mesh-sdk it pins has no "+
-					"composer command (before issue 1621)", at))
-				continue
-			}
-			fails = append(fails, fmt.Sprintf("the composer of the mesh-sdk %s pins did not run: %s %s", at, r.Ran.State, r.Ran.Reason))
-			continue
-		}
-		read, ok := caseOf(r.Ran.Verdict, CaseChange)
-		if !ok {
-			fails = append(fails, fmt.Sprintf("the composer of the mesh-sdk %s pins answered no change case", at))
-			continue
-		}
-		for _, name := range sortedKeys(c.Digests) {
-			if !head.Manifests[name].Accepted || read.Manifests[name].Accepted {
-				continue
-			}
-			fails = append(fails, fmt.Sprintf("the manifest of %s uses what %s (mesh-sdk %s) cannot read: %s; the group must move %s onto "+
-				"mesh-sdk %s", name, at, r.Ran.Verdict.SDK, read.Manifests[name].Refused, r.Module, c.SDKHead))
-		}
-	}
-	return fails, warnings
-}

modules/mesh-delivery-assigner/internal/assign/composer_test.go

@@ -1,204 +0,0 @@
-package assign
-
-import (
-	"encoding/json"
-	"slices"
-	"strings"
-	"testing"
-	"time"
-
-	"git.novox.be/novox/mesh-sdk/go/catalogue"
-	"git.novox.be/novox/mesh-sdk/go/compose"
-	"git.novox.be/novox/mesh-sdk/go/composer"
-	"git.novox.be/novox/mesh-sdk/go/delivery"
-)
-
-var testTime = time.Date(2026, 10, 24, 3, 0, 0, 0, time.UTC)
-
-const sdkHead = "1111111111111111111111111111111111111111"
-
-// raws are the manifests of meshOf as their repositories hold them, by digest, as the indexer keeps them; `web2` is web
-// with a field `shares` that the assigner's own mesh-sdk does not read (the shape of issue 1593).
-var raws = map[string]string{
-	"d-mail":  `{"module": "mail", "version": "1", "requires": ["postgres-database"]}`,
-	"d-store": `{"module": "store", "version": "1", "provides": [{"name": "postgres-database"}]}`,
-	"d-web":   `{"module": "web", "version": "1"}`,
-	"d-web2":  `{"module": "web", "version": "2", "shares": ["photos"]}`,
-}
-
-// asTheHeadReads is how mesh-sdk at the group's head reads each manifest: as the assigner's own reads it, but for the
-// field it adds, which it accepts. The head's composer is built and run by the Go build module (ADR 0482 clause 4); here
-// its verdict is made by mesh-sdk's composer.Run over the same request, with `web2` read as the head reads it.
-var asTheHeadReads = map[string]string{"d-web2": `{"module": "web", "version": "2"}`}
-
-func digestedMesh() Mesh {
-	m := meshOf()
-	m.Digests = map[string]string{"mail": "d-mail", "store": "d-store", "web": "d-web"}
-	return m
-}
-
-// webShares is a group of mesh-sdk and mesh-catalog whose catalogue member gives web the field only the SDK head reads:
-// the assigner's own reader refuses it (Unreadable), as the indexer's manifest is read in world.change.
-func webShares(members map[string]string) Change {
-	_, err := catalogue.ParseManifest([]byte(raws["d-web2"]))
-	return Change{Group: "g", Heads: "0123456789ab", SDKHead: sdkHead, Manifests: map[string]catalogue.Manifest{},
-		Unreadable: map[string]string{"web": err.Error()}, Digests: map[string]string{"web": "d-web2"}, Members: members}
-}
-
-// run is the composer's step for a job, as the build module answers it: the request filled from the indexer's digests
-// (with read standing in for how that mesh-sdk reads a digest), run, and its verdict put in a passed step.
-func run(t *testing.T, job delivery.ComposeJob, read map[string]string) Ran {
-	t.Helper()
-	req, err := composer.Decode(job.Request)
-	if err != nil {
-		t.Fatal(err)
-	}
-	if err := composer.Fill(&req, func(d string) ([]byte, error) {
-		if r, ok := read[d]; ok {
-			return []byte(r), nil
-		}
-		return []byte(raws[d]), nil
-	}); err != nil {
-		t.Fatal(err)
-	}
-	v, err := composer.Run(req)
-	if err != nil {
-		t.Fatal(err)
-	}
-	v.SDK = "(devel) " + job.Fetch["commit"].(string)
-	vr, _ := json.Marshal(v)
-	ans, _ := json.Marshal(delivery.ComposeAnswer{Built: true, Key: "composer-0", Verdict: vr})
-	return RanOf(delivery.Step{State: delivery.StepPassed, Result: ans})
-}
-
-// 1622/AC1: a group holding a mesh-sdk pull request is composed by the composer built at the member's head: the job
-// fetches mesh-sdk at that head, builds mesh-sdk's composer command in its Go module, and hands it the trunk and the
-// change by digest, never the manifests' bytes, composing the machines the change touches.
-func TestAGroupWithAnSDKMemberAsksTheComposerAtItsHead(t *testing.T) {
-	c := webShares(nil)
-	job, err := HeadJob(digestedMesh(), c)
-	if err != nil {
-		t.Fatal(err)
-	}
-	if job.Fetch["repository"] != SDKRepository || job.Fetch["commit"] != sdkHead || job.Dir != "go" || job.Package != composer.Package {
-		t.Fatalf("job = %+v", job)
-	}
-	ask := delivery.StepAsk{ID: "mh3k2x9qa1b2c5", Kind: delivery.AskCheck, Language: delivery.AskGo, Asker: "mesh-delivery-assigner",
-		At: testTime, Compose: &job}
-	if _, err := delivery.EncodeStepAsk(ask); err != nil {
-		t.Fatalf("the ask is refused by its layout: %v", err)
-	}
-	req, err := composer.Decode(job.Request)
-	if err != nil {
-		t.Fatal(err)
-	}
-	if len(req.Cases) != 2 || req.Cases[0].Name != CaseTrunk || req.Cases[1].Name != CaseChange {
-		t.Fatalf("cases = %+v", req.Cases)
-	}
-	if req.Cases[0].Manifests["web"].Digest != "d-web" || req.Cases[1].Manifests["web"].Digest != "d-web2" || len(req.Cases[1].Manifests["web"].Raw) != 0 {
-		t.Errorf("the cases do not name web by its trunk and its change digest: %+v", req.Cases)
-	}
-	if !slices.Equal(req.Machines, []string{"g14"}) || req.Depth != composer.DepthResolve || !req.HoldingsFromClaims {
-		t.Errorf("request = machines %v, depth %q, holdings from claims %v", req.Machines, req.Depth, req.HoldingsFromClaims)
-	}
-
-	// 1126 (ADR 0547 §2, ADR 0549 §3): once the catalogue places the nodes, the check composes over the input the nodes
-	// compose from (frombus), its catalogue left to the cases, and the seats held as placement says.
-	m := digestedMesh()
-	m.Input = &compose.Input{Catalogue: map[string]catalogue.Manifest{"web": {Module: "web"}},
-		Nodes:    []compose.Node{{Name: "g14", Assigned: []string{"web"}, Place: compose.Place{Endpoint: "g14.example:51820"}}},
-		Holdings: []catalogue.Held{{Claim: "web-seat", Scope: "mesh", Node: "g14", Module: "web"}}}
-	placedJob, err := HeadJob(m, c)
-	if err != nil {
-		t.Fatal(err)
-	}
-	placed, err := composer.Decode(placedJob.Request)
-	if err != nil {
-		t.Fatal(err)
-	}
-	if placed.Input.Catalogue != nil || len(placed.Input.Nodes) != 1 || placed.Input.Nodes[0].Place.Endpoint != "g14.example:51820" ||
-		len(placed.Input.Holdings) != 1 || placed.HoldingsFromClaims {
-		t.Errorf("the placed check's request = %+v, holdings from claims %v", placed.Input, placed.HoldingsFromClaims)
-	}
-}
-
-// 1622/AC2, AC3: a catalogue member using a field only the SDK head reads passes with the head's composer, and the
-// verdict names the mesh-sdk the composer was built with; with the assigner's own mesh-sdk it fails.
-func TestAFieldTheGroupAddsPassesWithTheHeadsComposer(t *testing.T) {
-	c := webShares(map[string]string{"novox/mesh-controller": "2222222222222222222222222222222222222222"})
-	job, _ := HeadJob(digestedMesh(), c)
-	head := run(t, job, asTheHeadReads)
-	v := FromComposer(digestedMesh(), c, head, nil, 0)
-	if v.State != delivery.CompositionPass || v.SDK != "(devel) "+sdkHead || !slices.Equal(v.Machines, []string{"g14"}) {
-		t.Fatalf("with the head's composer: %+v", v)
-	}
-	if _, err := delivery.EncodeCompositionVerdict(v); err != nil {
-		t.Errorf("the verdict cannot be written: %v", err)
-	}
-	own := Compose(digestedMesh(), c, "v0.1.14-own", 0)
-	if own.State != delivery.CompositionFail || !strings.Contains(own.Words, "shares") {
-		t.Fatalf("with the assigner's own mesh-sdk: %+v, want a fail naming the field", own)
-	}
-}
-
-// 1623/AC1, AC2: the group of mesh-sdk and mesh-catalog adding and using a field, without a controller member, fails
-// naming the field and mesh-controller, whose running build pins an older mesh-sdk; with a controller member pinned to
-// the SDK head (its composer reads what the head reads) it passes.
-func TestAFieldTheRunningControllerCannotReadFailsTheGroup(t *testing.T) {
-	c := webShares(nil)
-	job, _ := HeadJob(digestedMesh(), c)
-	head := run(t, job, asTheHeadReads)
-	running := "3333333333333333333333333333333333333333"
-	rjob, err := ReaderJob(c, "mesh-controller", "novox/mesh-controller", running)
-	if err != nil {
-		t.Fatal(err)
-	}
-	if rjob.Fetch["commit"] != running || rjob.Dir != delivery.RootPath {
-		t.Fatalf("reader job = %+v", rjob)
-	}
-	old := run(t, rjob, nil) // the running controller's mesh-sdk reads web2 as the assigner's own does: refused
-	v := FromComposer(digestedMesh(), c, head, []Reader{{Module: "mesh-controller", Commit: running, Ran: old}}, 0)
-	if v.State != delivery.CompositionFail || !strings.Contains(v.Words, "shares") || !strings.Contains(v.Words, "move mesh-controller onto mesh-sdk "+sdkHead) {
-		t.Fatalf("without a controller member: %+v, want a fail naming the field and mesh-controller", v)
-	}
-	member := "2222222222222222222222222222222222222222"
-	pinned := run(t, rjob, asTheHeadReads)
-	v = FromComposer(digestedMesh(), c, head, []Reader{{Module: "mesh-controller", Commit: member, Member: true, Ran: pinned}}, 0)
-	if v.State != delivery.CompositionPass {
-		t.Fatalf("with a controller member pinned to the head: %+v, want a pass", v)
-	}
-}
-
-// 1623: a reader whose mesh-sdk has no composer command (before issue 1621) is said, not failed; a reader's composer that
-// failed for another cause fails the group, loud.
-func TestAReaderWithNoComposerIsSaidAndAnotherFailureFails(t *testing.T) {
-	c := webShares(nil)
-	job, _ := HeadJob(digestedMesh(), c)
-	head := run(t, job, asTheHeadReads)
-	none := Ran{State: delivery.StepFailed, Reason: "go build: no required module provides package git.novox.be/novox/mesh-sdk/go/cmd/mesh-compose"}
-	v := FromComposer(digestedMesh(), c, head, []Reader{{Module: "mesh-host", Commit: "abc", Ran: none}}, 0)
-	if v.State != delivery.CompositionPass || !hasWarning(v, "mesh-host at abc") || !hasWarning(v, "before issue 1621") {
-		t.Fatalf("a reader with no composer: %+v", v)
-	}
-	broke := Ran{State: delivery.StepFailed, Reason: "the fetch could not reach the forge"}
-	v = FromComposer(digestedMesh(), c, head, []Reader{{Module: "mesh-host", Commit: "abc", Ran: broke}}, 0)
-	if v.State != delivery.CompositionFail || !strings.Contains(v.Words, "could not reach the forge") {
-		t.Fatalf("a reader whose composer failed: %+v", v)
-	}
-}
-
-// 1622: the head's composer that did not run fails the composition naming why, never passes it; a trunk manifest the
-// head's mesh-sdk refuses fails it too, since the group would deliver a reader that refuses it.
-func TestTheHeadsComposerFailingOrRefusingTheTrunkFails(t *testing.T) {
-	c := webShares(nil)
-	v := FromComposer(digestedMesh(), c, Ran{State: delivery.StepRefused, Reason: "the guard refuses it"}, nil, 0)
-	if v.State != delivery.CompositionFail || !strings.Contains(v.Words, "the guard refuses it") || !strings.Contains(v.Words, sdkHead) {
-		t.Fatalf("a head composer that did not run: %+v", v)
-	}
-	job, _ := HeadJob(digestedMesh(), c)
-	strict := map[string]string{"d-web2": asTheHeadReads["d-web2"], "d-mail": `{"module": "mail", "version": "1", "gone": true}`}
-	v = FromComposer(digestedMesh(), c, run(t, job, strict), nil, 0)
-	if v.State != delivery.CompositionFail || !strings.Contains(v.Words, "refuses the trunk's manifest of mail") {
-		t.Fatalf("a head that refuses a trunk manifest: %+v", v)
-	}
-}

modules/mesh-delivery-assigner/internal/assign/findings.go

@@ -0,0 +1,105 @@
+package assign
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+
+	occ "git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient"
+	oc "git.novox.be/novox/mesh-contracts/go/seats/operatorchannel"
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/health"
+)
+
+// The assigner's said conditions become findings (novox/hq ADR 0564 §2, issue 1952 WM6, note 16): every condition it says
+// under its own name (ADR 0437 §9) — a hold and its lift, a node failing alone, a module on neither list, a backup, a pair
+// placed by one source, the seat waiting for its states — is also a finding in its own bucket `findings`, written at its
+// raise and deleted at its clear, which the condition keeper raises and clears. Until the operator's take-over the router
+// hears it straight from the assigner, as before; from the take-over the keeper's condition is the one said, so the
+// assigner no longer says it straight (never both).
+
+// FindingsBucket is the assigner's findings.
+var FindingsBucket = health.FindingsBucket(delivery.AssignerModule)
+
+// FindingOf is a said condition as a finding: its key `<scope>.<id>.<kind>`, from the condition's own key
+// `mesh-delivery-assigner.<kind>.<id…>` (the subject's id when the key names none), its words unchanged. raised is false for
+// a clear, whose key is to be deleted; value is nil then.
+func FindingOf(c oc.Condition, at time.Time) (key string, value []byte, raised bool, err error) {
+	rest, ok := strings.CutPrefix(c.Key, delivery.AssignerModule+".")
+	if !ok || rest == "" {
+		return "", nil, false, fmt.Errorf("the condition %q is not the assigner's", c.Key)
+	}
+	kind, id, _ := strings.Cut(rest, ".")
+	if id == "" {
+		id = c.Subject.ID
+	}
+	scope := c.Subject.Scope
+	if scope == "" {
+		scope = health.ScopeModule
+	}
+	key = health.FindingKey(scope, id, kind)
+	if c.State == occ.StateCleared {
+		return key, nil, false, nil
+	}
+	if c.State != occ.StateRaised {
+		return "", nil, false, fmt.Errorf("the condition %s is neither raised nor cleared", c.Key)
+	}
+	summary := c.Summary
+	if summary == "" {
+		summary = c.Headline
+	}
+	var actions []health.Action
+	for _, a := range c.Actions {
+		actions = append(actions, health.Action{Label: a.Label, Verb: a.Verb, Machine: a.Machine, Arguments: a.Arguments, Level: string(a.Level)})
+	}
+	value, err = health.EncodeFinding(health.Finding{Key: key, Kind: kind, Subject: health.Subject{Scope: scope, ID: id, Machine: c.Subject.Machine},
+		Severity: health.Severity(c.Severity), Summary: summary, Headline: c.Headline, Explanation: c.Explanation, Resolved: c.Resolved,
+		Needs: c.Needs, Actions: actions, Evidence: []health.Evidence{{At: at.UTC(), Said: summary}}, Source: "assigner." + kind,
+		Observer: delivery.AssignerModule, At: at.UTC()})
+	return key, value, true, err
+}
+
+// Findings is where the assigner's findings go: the bucket's put and delete.
+type Findings struct {
+	Put    func(key string, value []byte) error
+	Delete func(key string) error
+	Keys   func() ([]string, error)
+	Now    func() time.Time
+}
+
+// Say is say with each condition written as a finding (or its finding deleted), which the condition keeper carries, the
+// one source since the controller's end (novox/hq ADR 0590 §3); said straight to the router only where there is no
+// findings bucket at all. A finding that cannot be written is the error.
+func (f Findings) Say(say func(oc.Condition) error) func(oc.Condition) error {
+	return func(c oc.Condition) error {
+		var errs []error
+		if f.Put != nil {
+			now := time.Now
+			if f.Now != nil {
+				now = f.Now
+			}
+			key, value, raised, err := FindingOf(c, now())
+			switch {
+			case err != nil:
+				errs = append(errs, err)
+			case raised:
+				if err := f.Put(key, value); err != nil {
+					errs = append(errs, fmt.Errorf("the finding %s cannot be written: %w", key, err))
+				}
+			default:
+				if err := f.Delete(key); err != nil {
+					errs = append(errs, fmt.Errorf("the finding %s cannot be deleted: %w", key, err))
+				}
+			}
+		}
+		if f.Put == nil {
+			if say != nil {
+				if err := say(c); err != nil {
+					errs = append(errs, err)
+				}
+			}
+		}
+		return errors.Join(errs...)
+	}
+}

modules/mesh-delivery-assigner/internal/assign/placement.go

@@ -1,121 +1,23 @@
 package assign
 
 import (
-	"fmt"
-	"sort"
 	"strings"
 
-	"git.novox.be/novox/mesh-sdk/go/asks"
+	occ "git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient"
+	oc "git.novox.be/novox/mesh-contracts/go/seats/operatorchannel"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
 )
 
-// Until ADR 0547's third milestone two sources name which module runs on which node: the controller's assignments and
-// the seat mesh-placement's placement (ADR 0549 §5, ADR 0567 §8). The assigner writes wants only for a pair both name:
-// for a pair one source names alone it writes no want and touches none it wrote before, so nothing moves and nothing is
-// removed on one source's word, and it raises a condition naming the pair until both agree. After an approved proposal
-// the assigner keeps the controller in step itself, calling its assign, unassign, pin and unpin; a call refused or not
-// yet answered leaves the pair differing, and the condition names the call (Pair.Call). Before the first placement key
-// is written the controller's assignments are the one source, as before.
-
-// Pair is a module on a node that one source names and the other does not; Only says which: OnlyAssignments or
-// OnlyPlacement.
-type Pair struct {
-	Node, Module, Only string
-	// Call is what became of the assigner's call of the controller's verb for the pair, in words, when it made one.
-	Call string
-}
-
-// The source that names a pair alone.
-const (
-	OnlyAssignments = "the controller's assignments"
-	OnlyPlacement   = "the seat mesh-placement's placement"
-)
-
-// Placed is, by node, the modules both sources name, in name order, and every pair one names alone, by node then
-// module. With no placement read yet (seeded false) it is the assignments, and no pair differs.
-func Placed(assigned, placed map[string][]string, seeded bool) (map[string][]string, []Pair) {
-	if !seeded {
-		return assigned, nil
-	}
-	set := func(m map[string][]string) map[string]bool {
-		out := map[string]bool{}
-		for node, modules := range m {
-			for _, module := range modules {
-				out[node+"\x00"+module] = true
-			}
-		}
-		return out
-	}
-	inAssigned, inPlaced := set(assigned), set(placed)
-	both := map[string][]string{}
-	var differ []Pair
-	for node, modules := range assigned {
-		for _, module := range modules {
-			if inPlaced[node+"\x00"+module] {
-				both[node] = append(both[node], module)
-			} else {
-				differ = append(differ, Pair{Node: node, Module: module, Only: OnlyAssignments})
-			}
-		}
-	}
-	for node, modules := range placed {
-		for _, module := range modules {
-			if !inAssigned[node+"\x00"+module] {
-				differ = append(differ, Pair{Node: node, Module: module, Only: OnlyPlacement})
-			}
-		}
-	}
-	for _, modules := range both {
-		sort.Strings(modules)
-	}
-	sort.Slice(differ, func(i, j int) bool {
-		if differ[i].Node != differ[j].Node {
-			return differ[i].Node < differ[j].Node
-		}
-		return differ[i].Module < differ[j].Module
-	})
-	return both, differ
-}
-
-// PlacementCondition is the condition of a pair the two sources do not both name: raised while they differ, cleared once
-// both name it or neither does.
-func PlacementCondition(p Pair, raised bool) asks.Condition {
-	key := delivery.AssignerModule + ".placement." + p.Node + "." + p.Module
-	subject := asks.Scope{Scope: "module", ID: p.Module, Machine: p.Node}
-	if !raised {
-		return asks.Condition{Key: key, Subject: subject, State: asks.StateCleared,
-			Resolved: fmt.Sprintf("the controller's assignments and the seat's placement agree on %s on %s.", p.Module, p.Node)}
-	}
-	headline := fmt.Sprintf("%s on %s is placed by one source only", p.Module, p.Node)
-	if n := len([]rune(headline)); n > asks.HeadlineLength {
-		headline = string([]rune(headline)[:asks.HeadlineLength])
-	}
-	var needs string
-	if p.Only == OnlyAssignments {
-		needs = fmt.Sprintf("propose placing %s on %s (mesh-placement.propose), or unassign it at the controller", p.Module, p.Node)
-	} else {
-		needs = fmt.Sprintf("assign %s to %s at the controller, as the approved placement says, or propose taking it off", p.Module, p.Node)
-	}
-	if p.Call != "" {
-		needs += "; the assigner's call: " + p.Call
-	}
-	return asks.Condition{Key: key, Severity: asks.SeverityUrgent, Subject: subject, State: asks.StateRaised,
-		Summary: headline, Headline: headline, Needs: needs,
-		Explanation: fmt.Sprintf("%s%s. %s names %s on %s and the other source does not. Until ADR 0547's third milestone both must "+
-			"name a module on a node (ADR 0549 §5): the assigner writes no want for it there and leaves the one it wrote before, so "+
-			"nothing moves or is removed. This clears once both name it or neither does.", asks.NeedsYou, needs, p.Only, p.Module, p.Node)}
-}
-
 // SeatWaitsCondition is the assigner's word on the seat mesh-placement while a state of the seat is not bound (ADR 0567
 // §1): raised naming each, cleared when none is left.
-func SeatWaitsCondition(unbound []string) asks.Condition {
+func SeatWaitsCondition(unbound []string) oc.Condition {
 	key := delivery.AssignerModule + ".seat-states"
-	subject := asks.Scope{Scope: "module", ID: delivery.AssignerModule}
+	subject := oc.ConditionSubject{Scope: "module", ID: delivery.AssignerModule}
 	if len(unbound) == 0 {
-		return asks.Condition{Key: key, Subject: subject, State: asks.StateCleared, Resolved: "the seat mesh-placement holds all its states."}
+		return oc.Condition{Key: key, Subject: subject, State: occ.StateCleared, Resolved: "the seat mesh-placement holds all its states."}
 	}
 	why := "the seat waits for its states: " + strings.Join(unbound, ", ") + " are not on the bus or not granted yet"
-	return asks.Condition{Key: key, Severity: asks.SeverityWarning, Subject: subject, State: asks.StateRaised,
+	return oc.Condition{Key: key, Severity: occ.SeverityWarning, Subject: subject, State: occ.StateRaised,
 		Summary: "the seat waits for its states", Headline: "the seat waits for its states",
-		Explanation: asks.NothingToDo + " " + why + "; each is bound at the next pass once it is, with no restart."}
+		Explanation: occ.NothingToDo + " " + why + "; each is bound at the next pass once it is, with no restart."}
 }

modules/mesh-delivery-assigner/internal/assign/policy.go

@@ -0,0 +1,135 @@
+package assign
+
+import (
+	"encoding/json"
+	"fmt"
+	"sort"
+	"strings"
+	"time"
+
+	occ "git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient"
+	"git.novox.be/novox/mesh-sdk/go/catalogue"
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/health"
+	"git.novox.be/novox/mesh-sdk/go/provisions"
+)
+
+// A person's upgrade policy is the assigner's (novox/hq ADR 0565 §7, §8, issue 1953 D4, D5): kept in its state `policies`, one
+// key per module, set and taken back through `mesh-wants.upgrade`. Every reader takes one derivation, mesh-sdk's
+// catalogue.Upgrade: a person's choice over the module's word, its irreplaceable data and the default, the bus as any module (ADR 0601 §1).
+
+// PoliciesBucket is the assigner's state `policies`.
+var PoliciesBucket = delivery.AssignerModule + "_" + delivery.AssignerPoliciesState
+
+// DecodePolicies reads the policies state's values by key (the module); a value that cannot be read is left out, named.
+func DecodePolicies(values map[string][]byte) (map[string]catalogue.PersonPolicy, []string) {
+	out := map[string]catalogue.PersonPolicy{}
+	var bad []string
+	for key, raw := range values {
+		var p catalogue.PersonPolicy
+		if err := json.Unmarshal(raw, &p); err != nil || p.V != catalogue.PersonPolicyVersion || p.Check() != nil || p.Module != key {
+			bad = append(bad, key)
+			continue
+		}
+		out[key] = p
+	}
+	sort.Strings(bad)
+	return out, bad
+}
+
+// PolicyOf is a module's policy and where it comes from, with the person's choice for it when there is one.
+func PolicyOf(m catalogue.Manifest, chosen map[string]catalogue.PersonPolicy) (policy, from, why, by string) {
+	var c *catalogue.PersonPolicy
+	if p, ok := chosen[m.Module]; ok {
+		c = &p
+	}
+	return catalogue.Upgrade(m, c)
+}
+
+func contains(list []string, s string) bool {
+	for _, v := range list {
+		if v == s {
+			return true
+		}
+	}
+	return false
+}
+
+// KindProvisionFailed is the assigner's finding of a provision its module's want waits for that failed (ADR 0570 §4).
+const KindProvisionFailed = "provision-failed"
+
+// ProvisionFailedKey is a failed provision's finding's key, `provider.<node>.<consumer>.<provision>[.<local>].provision-failed`.
+func ProvisionFailedKey(key string) string {
+	return health.FindingKey(health.ScopeProvider, key, KindProvisionFailed)
+}
+
+// ProvisionFailedFinding is the finding of a failed provision, naming its consumer, its provider and why.
+func ProvisionFailedFinding(key string, p provisions.Provision, at time.Time) ([]byte, error) {
+	summary := fmt.Sprintf("%s for %s on %s failed at %s on %s: %s, so %s is not moved there until it is provided", p.Provision,
+		p.Consumer.Module, p.Consumer.Node, p.Provider.Module, p.Provider.Node, p.Why, p.Consumer.Module)
+	return health.EncodeFinding(health.Finding{Key: ProvisionFailedKey(key), Kind: KindProvisionFailed,
+		Subject:  health.Subject{Scope: health.ScopeProvider, ID: key, Machine: p.Consumer.Node, Also: also(p.Provider.Node, p.Consumer.Node)},
+		Severity: health.Warning, Summary: summary, Headline: clipHeadline(p.Consumer.Module + " waits for a provision that failed"),
+		Explanation: occ.NothingToDo + " " + summary + ". It clears once the provider provides it.",
+		Resolved:    p.Provision + " for " + p.Consumer.Module + " is provided", Evidence: []health.Evidence{{At: at.UTC(), Said: p.Why}},
+		Source: "assigner." + KindProvisionFailed, Observer: delivery.AssignerModule, At: at.UTC()})
+}
+
+func also(provider, consumer string) []string {
+	if provider == "" || provider == consumer {
+		return nil
+	}
+	return []string{provider}
+}
+
+// KindProvisionMissing is the assigner's finding of a required provision that has had no key for longer than its bound.
+const KindProvisionMissing = "provision-missing"
+
+// ProvisionMissingKey is its key, `provider.<node>.<module>.<provision>.provision-missing`.
+func ProvisionMissingKey(key string) string {
+	return health.FindingKey(health.ScopeProvider, key, KindProvisionMissing)
+}
+
+// ProvisionMissingFinding is the finding of a required provision with no key past bound (key `<node>.<module>.<provision>`).
+func ProvisionMissingFinding(key string, bound time.Duration, at time.Time) ([]byte, error) {
+	parts := strings.SplitN(key, ".", 3)
+	if len(parts) != 3 {
+		return nil, fmt.Errorf("%q is not <node>.<module>.<provision>", key)
+	}
+	node, module, provision := parts[0], parts[1], parts[2]
+	summary := fmt.Sprintf("%s on %s requires %s and mesh-provisioner has composed no key for it in %s, so %s is not moved there: "+
+		"no provider of it may be placed", module, node, provision, bound, module)
+	return health.EncodeFinding(health.Finding{Key: ProvisionMissingKey(key), Kind: KindProvisionMissing,
+		Subject:  health.Subject{Scope: health.ScopeProvider, ID: key, Machine: node},
+		Severity: health.Warning, Summary: summary, Headline: clipHeadline(module + " on " + node + " lacks " + provision),
+		Explanation: occ.NothingToDo + " " + summary + ". It clears once the provision has its key.",
+		Resolved:    provision + " for " + module + " on " + node + " has its key", Evidence: []health.Evidence{{At: at.UTC(), Said: summary}},
+		Source: "assigner." + KindProvisionMissing, Observer: delivery.AssignerModule, At: at.UTC()})
+}
+
+// KindUnplaced is, from the lease write, a node that runs but no placement names (ADR 0571 §6).
+const KindUnplaced = "unplaced"
+
+// UnplacedKey is its finding's key, `machine.<node>.unplaced`.
+func UnplacedKey(node string) string {
+	return health.FindingKey(health.ScopeMachine, node, KindUnplaced)
+}
+
+// UnplacedFinding is the finding of a node no placement names since the lease write.
+func UnplacedFinding(node string, at time.Time) ([]byte, error) {
+	summary := fmt.Sprintf("%s runs, but no placement names it: since the controller handed its lease away nothing composes it, "+
+		"so the assigner writes it no want", node)
+	return health.EncodeFinding(health.Finding{Key: UnplacedKey(node), Kind: KindUnplaced,
+		Subject: health.Subject{Scope: health.ScopeMachine, ID: node, Machine: node}, Severity: health.Warning, Summary: summary,
+		Headline: clipHeadline(node + " has no placement"), Needs: "place it with mesh-placement.propose.",
+		Explanation: occ.NeedsYou + "place it with mesh-placement.propose. " + summary + ".",
+		Resolved:    node + " is placed", Evidence: []health.Evidence{{At: at.UTC(), Said: summary}},
+		Source: "assigner." + KindUnplaced, Observer: delivery.AssignerModule, At: at.UTC()})
+}
+
+func clipHeadline(s string) string {
+	if len([]rune(s)) <= 60 {
+		return s
+	}
+	return string([]rune(s)[:60])
+}

modules/mesh-delivery-assigner/internal/assign/put.go

@@ -4,7 +4,8 @@ import (
 	"fmt"
 	"time"
 
-	"git.novox.be/novox/mesh-sdk/go/asks"
+	occ "git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient"
+	oc "git.novox.be/novox/mesh-contracts/go/seats/operatorchannel"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
 )
 
@@ -68,7 +69,7 @@ func StepPut(w PutWorld) PutNext {
 	}
 	fp := short(p.FP)
 	if !w.Assigned {
-		return say(delivery.PutRefused, "%s is not assigned to %s: a put moves a module where it stands assigned (mesh-controller.assign first)", w.Module, w.Node)
+		return say(delivery.PutRefused, "%s is not assigned to %s: a put moves a module where it stands assigned (propose its placement first)", w.Module, w.Node)
 	}
 	switch w.Build {
 	case delivery.BuildDone:
@@ -210,15 +211,15 @@ func PutAsking(p delivery.Put) int {
 }
 
 // PutAct is the act a bus put's yes binds and that is performed when its want is written.
-func PutAct(node, module, fp, composed string) asks.Act {
-	return asks.Act{"put": "want", "node": node, "module": module, "fp": fp, "composed": composed}
+func PutAct(node, module, fp, composed string) occ.Act {
+	return occ.Act{"put": "want", "node": node, "module": module, "fp": fp, "composed": composed}
 }
 
 // PutAsk is the ask about a put's move (ADR 0546 clauses 7 and 8), under the record ask's key of the composition so the
 // teller relays it and its answer as any record ask's. For the bus its yes is of level approve and binds the act, so only a
 // channel that proves who answered takes it (ADR 0259), never the view.
 func PutAsk(key, node, module string, p delivery.Put, d delivery.ComposedDigest, bus bool, now time.Time) (delivery.AssignerAsk, error) {
-	yes := asks.Option{ID: OptionYes, Label: "Yes, put it", Does: "the node is told to apply " + module + " at " + short(p.FP), Level: asks.Acknowledge}
+	yes := oc.Option{ID: OptionYes, Label: "Yes, put it", Does: "the node is told to apply " + module + " at " + short(p.FP), Level: occ.Acknowledge}
 	what := map[delivery.Judgement]string{
 		delivery.JudgedRecreates: "recreates a container",
 		delivery.JudgedMovesData: "moves the module's data",
@@ -227,26 +228,26 @@ func PutAsk(key, node, module string, p delivery.Put, d delivery.ComposedDigest,
 		delivery.JudgedUnchanged: "changes nothing the node runs",
 	}[d.Judgement]
 	explanation := fmt.Sprintf("Asked to put %s at version %s on %s: %s. The move %s.", module, short(p.FP), node, p.Why, what)
-	expires := now.Add(7 * 24 * time.Hour)
+	expires := occ.FormatTime(now.Add(7 * 24 * time.Hour))
 	if bus {
-		binds, err := asks.ActDigest(PutAct(node, module, p.FP, d.Digest))
+		binds, err := occ.ActDigest(PutAct(node, module, p.FP, d.Digest))
 		if err != nil {
 			return delivery.AssignerAsk{}, err
 		}
-		yes.Level, yes.Binds = asks.Approve, binds
+		yes.Level, yes.Binds = occ.Approve, binds
 		yes.Does = "the bus's streams are snapshotted, then " + node + " is told to apply the bus at " + short(p.FP)
 		explanation += " It is the mesh's bus: every module reconnects while it restarts, and its streams are snapshotted first."
-		expires = now.Add(asks.ApproveLasts)
+		expires = occ.FormatTime(now.Add(occ.ApproveLasts))
 	}
-	return delivery.AssignerAsk{Ask: asks.Ask{
+	return assignerAsk(PutAsking(p), oc.Ask{
 		ID:          delivery.AskingID(key, PutAsking(p)),
 		Headline:    fmt.Sprintf("Put %s on %s?", module, node),
 		Explanation: explanation,
-		Options: []asks.Option{yes,
-			{ID: OptionNo, Label: "No", Does: "the node keeps what it runs, and the put is refused", Level: asks.Acknowledge}},
-		Who:      asks.Operator,
+		Options: []oc.Option{yes,
+			{ID: OptionNo, Label: "No", Does: "the node keeps what it runs, and the put is refused", Level: occ.Acknowledge}},
+		Who:      occ.Operator,
 		Expires:  expires,
 		OnExpiry: "the node keeps what it runs",
 		About:    key,
-	}, Asking: PutAsking(p)}, nil
+	}), nil
 }

modules/mesh-delivery-assigner/internal/assign/seat.go

@@ -1,13 +1,14 @@
 package assign
 
 import (
-	"encoding/json"
 	"fmt"
-	"sort"
+	"maps"
+	"slices"
 	"strings"
 	"time"
 
-	"git.novox.be/novox/mesh-sdk/go/asks"
+	occ "git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient"
+	oc "git.novox.be/novox/mesh-contracts/go/seats/operatorchannel"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
 )
 
@@ -15,34 +16,29 @@ import (
 // `placement`, changed only by a proposal (§2) the nodes it touches answer (§3), judged (§4) and written on the
 // operator's Approve at the revision it was laid over (§5). What here decides; the tools and the passes do.
 
-// Leased says whether the lease write of ADR 0547 has happened, after which the controller's assignments are read no
-// more (§8). Not before L3: until then the holder keeps the controller in step and refuses what its verbs cannot take.
-var Leased = false
-
 // ProposeIn is what a proposal is laid over: its id, who and why, its changes; every node's current placement and the
 // revision of its key; which modules the indexer holds and which nodes have a record; and, for the seed, the export's
 // digest.
 type ProposeIn struct {
-	ID, By, Why  string
-	At           time.Time
-	Changes      []delivery.PlacementProposalChange
-	Current      map[string]delivery.Placement
-	Revisions    map[string]uint64
-	Held         func(module string) bool
-	Recorded     func(node string) bool
-	Seed         bool
-	ExportDigest string
+	ID, By, Why string
+	At          time.Time
+	Changes     []delivery.PlacementProposalChange
+	Current     map[string]delivery.Placement
+	Revisions   map[string]uint64
+	Held        func(module string) bool
+	Recorded    func(node string) bool
+	// Warrant is the enrolment's warrant an add-node carries (ADR 0587 §7); only that change has one.
+	Warrant *delivery.AddNodeWarrant
 }
 
 // Propose lays a proposal over the current keys (§2): the proposal (state answering, each changed node's base revision),
-// the laid placement of every node whose key it changes, and every finding, which refuses it whole: a change the
-// controller's verbs cannot take before the lease write (§8), a change that does not fit its node, and what
+// the laid placement of every node whose key it changes, and every finding, which refuses it whole: a change that does not fit its node, and what
 // CheckPlacements refuses of the result laid over every placement (two modules on one host port, a provider not placed,
 // a seat held once held twice, two nodes with one address, two hubs, a module the indexer does not hold, a node with no
 // record). A key whose value the proposal leaves as it is changes nothing and is not laid.
 func Propose(in ProposeIn) (delivery.PlacementProposal, map[string]*delivery.Placement, []string) {
 	p := delivery.PlacementProposal{ID: in.ID, By: strings.TrimSpace(in.By), Why: strings.TrimSpace(in.Why), At: in.At.UTC(),
-		Changes: in.Changes, Seed: in.Seed, ExportDigest: in.ExportDigest, Base: map[string]uint64{}, State: delivery.ProposalAnswering}
+		Changes: in.Changes, Warrant: in.Warrant, Base: map[string]uint64{}, State: delivery.ProposalAnswering}
 	var findings []string
 	if p.By == "" {
 		findings = append(findings, "the runtime names no caller: a proposal is made by someone")
@@ -54,18 +50,13 @@ func Propose(in ProposeIn) (delivery.PlacementProposal, map[string]*delivery.Pla
 		findings = append(findings, "a proposal changes something: it names no change")
 	}
 	for i, c := range in.Changes {
-		if (c.Op == delivery.OpSeed) != in.Seed {
-			findings = append(findings, fmt.Sprintf("change %d: the seed is adopt's alone, and never mixed with other changes", i+1))
-			continue
-		}
-		if !Leased {
-			if why := c.BeforeLease(); why != "" {
-				findings = append(findings, fmt.Sprintf("change %d: %s", i+1, why))
-			}
+		if c.Op == delivery.OpSeed {
+			findings = append(findings, fmt.Sprintf("change %d: the seed is gone with adopt, the controller's export being gone", i+1))
 		}
 	}
 	laid, lay := delivery.LayChanges(in.Current, in.Changes)
 	findings = append(findings, lay...)
+	findings = append(findings, ControllerRefusals(in.Changes, laid)...)
 	all := map[string]delivery.Placement{}
 	for node, pl := range in.Current {
 		all[node] = pl
@@ -80,6 +71,16 @@ func Propose(in ProposeIn) (delivery.PlacementProposal, map[string]*delivery.Pla
 		out[node] = &pl
 		p.Base[node] = in.Revisions[node]
 	}
+	// A remove-node deletes the key of a joining node that never confirmed (the operator's decision of 2026-11-02 01:05): its
+	// candidate is no placement, and the checks across nodes read the mesh without it. LayChanges said why one cannot go.
+	for _, node := range p.RemovedNodes() {
+		if _, ok := in.Current[node]; !ok {
+			continue
+		}
+		delete(all, node)
+		out[node] = nil
+		p.Base[node] = in.Revisions[node]
+	}
 	if len(findings) == 0 && len(out) == 0 {
 		findings = append(findings, "the changes leave every placement as it is")
 	}
@@ -90,14 +91,58 @@ func Propose(in ProposeIn) (delivery.PlacementProposal, map[string]*delivery.Pla
 	if recorded == nil {
 		recorded = func(string) bool { return false }
 	}
+	// A joining node writes its record only once it holds its account, which the add-node's write gives it: this one change by
+	// this one caller is the exception to a node with no record (ADR 0587 §7, changing ADR 0567 §2).
+	joining := map[string]bool{}
+	for _, c := range in.Changes {
+		if c.Op == delivery.OpAddNode {
+			joining[c.Node] = true
+		}
+	}
+	if len(joining) > 0 {
+		was := recorded
+		recorded = func(node string) bool { return joining[node] || was(node) }
+	}
 	for _, r := range delivery.CheckPlacements(all, held, recorded) {
 		findings = append(findings, r)
 	}
 	return p, out, findings
 }
 
-// Write is one key a warrant writes (§5): the node, its key, the revision it is written at (0: it has none, so it is
-// created) and its value (nil: it is deleted).
+// ControllerModule is the controller's module, which nothing places again (issue 1126).
+const ControllerModule = "mesh-controller"
+
+// ControllerEnded is why a placement of the controller is refused: the parts that acted only once its lease was handed
+// (consumers, the user list, enrolment, dead letters) now act without reading the lease, so a controller placed again
+// would write beside them, silently.
+const ControllerEnded = "the controller ended by its unassignment on 2026-11-02; placing it again would make two writers (issue 1126)"
+
+// ControllerRefusals names every change, and every node as laid, that places the controller: by a place, by a seed's
+// whole placement, or in what the changes lay. None when nothing does.
+func ControllerRefusals(changes []delivery.PlacementProposalChange, laid map[string]delivery.Placement) []string {
+	var out []string
+	nodes := map[string]bool{}
+	for i, c := range changes {
+		places := c.Module == ControllerModule && c.Op != delivery.OpTakeOff
+		if c.Whole != nil && slices.Contains(c.Whole.Assigned(), ControllerModule) {
+			places = true
+		}
+		if places {
+			out = append(out, fmt.Sprintf("change %d places %s on %s: %s", i+1, ControllerModule, c.Node, ControllerEnded))
+			nodes[c.Node] = true
+		}
+	}
+	for _, node := range slices.Sorted(maps.Keys(laid)) {
+		if !nodes[node] && slices.Contains(laid[node].Assigned(), ControllerModule) {
+			out = append(out, fmt.Sprintf("%s would run %s: %s", node, ControllerModule, ControllerEnded))
+		}
+	}
+	return out
+}
+
+// Write is one node a warrant writes (§5): the node, its node key `<node>.node` (the commit of the node's keys,
+// mesh-sdk delivery.PlacementKeys.Writes), the revision of the node's placement it is written at (0: it has none, so
+// it is created) and its value (nil: it is deleted).
 type Write struct {
 	Node, Key string
 	Base      uint64
@@ -108,7 +153,7 @@ type Write struct {
 func Writes(p delivery.PlacementProposal, laid map[string]*delivery.Placement) ([]Write, error) {
 	var out []Write
 	for _, node := range p.Nodes() {
-		key, err := delivery.PlacementKey(node)
+		key, err := delivery.PlacementNodeKey(node)
 		if err != nil {
 			return nil, err
 		}
@@ -117,75 +162,24 @@ func Writes(p delivery.PlacementProposal, laid map[string]*delivery.Placement) (
 	return out, nil
 }
 
-// ControllerCall is one call of the controller's seat verbs the holder makes after writing an approved proposal, until
-// the lease write (§8): assign, unassign, pin or unpin, with its arguments.
-type ControllerCall struct {
-	Verb string
-	Args map[string]any
-	// Node and Module name the pair the call keeps in step (a pin names no module).
-	Node, Module string
-}
+// The kinds of the condition (and finding) of a refused controller call, which the assigner raised until it stopped calling
+// the controller's verbs (ADR 0567 §8, issue 774).
+const (
+	KindControllerCall = "controller-call"
+	KindControllerPin  = "controller-pin"
+)
 
-// Key names the call, as the condition of its pair says it.
-func (c ControllerCall) Key() string {
-	return fmt.Sprintf("mesh-controller.%s %s %s", c.Verb, c.Node, c.Module)
-}
-
-// ControllerCalls is every call that brings the controller's assignments and pins to the placement after: assign for a
-// module placed on a node before not, unassign for one taken off, pin for a pin set or changed, unpin for one removed,
-// each naming the proposal and its warrant in its why. In node order, unassigns before assigns, so a module moved
-// between nodes is first taken off.
-func ControllerCalls(before map[string]delivery.Placement, after map[string]*delivery.Placement, proposal, warrant string) []ControllerCall {
-	why := fmt.Sprintf("placement proposal %s, approved (%s)", proposal, warrant)
-	nodes := make([]string, 0, len(after))
-	for node := range after {
-		nodes = append(nodes, node)
-	}
-	sort.Strings(nodes)
-	var off, on, pins []ControllerCall
-	for _, node := range nodes {
-		was, now := before[node], delivery.Placement{}
-		if a := after[node]; a != nil {
-			now = *a
-		}
-		had, has := map[string]bool{}, map[string]bool{}
-		for _, m := range was.Modules {
-			had[m.Module] = true
-		}
-		for _, m := range now.Modules {
-			has[m.Module] = true
-			if !had[m.Module] {
-				on = append(on, ControllerCall{Verb: "assign", Node: node, Module: m.Module, Args: map[string]any{"node": node, "module": m.Module}})
-			}
-		}
-		for _, m := range was.Modules {
-			if !has[m.Module] {
-				off = append(off, ControllerCall{Verb: "unassign", Node: node, Module: m.Module, Args: map[string]any{"node": node, "module": m.Module}})
-			}
-		}
-		for _, provision := range sortedKeys(now.Pins) {
-			to := now.Pins[provision]
-			if old, ok := was.Pins[provision]; !ok || old != to {
-				pins = append(pins, ControllerCall{Verb: "pin", Node: node, Module: provision,
-					Args: map[string]any{"node": node, "provision": provision, "from": to.Node, "module": to.Module}})
-			}
-		}
-		for _, provision := range sortedKeys(was.Pins) {
-			if _, ok := now.Pins[provision]; !ok {
-				pins = append(pins, ControllerCall{Verb: "unpin", Node: node, Module: provision, Args: map[string]any{"node": node, "provision": provision}})
-			}
-		}
-	}
-	out := append(append(off, on...), pins...)
-	for i := range out {
-		out[i].Args["why"] = why
-	}
-	return out
+// CallClearedCondition clears the condition of a refused controller call a previous process raised, for its pair (node and
+// module, or node and provision for a pin).
+func CallClearedCondition(kind, node, module string) oc.Condition {
+	return oc.Condition{Key: delivery.AssignerModule + "." + kind + "." + node + "." + module,
+		Subject: oc.ConditionSubject{Scope: "module", ID: module, Machine: node}, State: occ.StateCleared,
+		Resolved: "the assigner calls no verb of the controller any more: placement is the one source."}
 }
 
 // PlacementAct is the act an approved proposal's yes binds: writing exactly its changes at its base revisions.
-func PlacementAct(p delivery.PlacementProposal) asks.Act {
-	return asks.Act{"placement": "write", "proposal": p.ID, "changes": delivery.ChangesDigest(p)}
+func PlacementAct(p delivery.PlacementProposal) occ.Act {
+	return occ.Act{"placement": "write", "proposal": p.ID, "changes": delivery.ChangesDigest(p)}
 }
 
 // PlacementAsking is a proposal's asking number: each judging that raises its ask again (again, a key moved) is
@@ -197,83 +191,29 @@ func PlacementAsking(p delivery.PlacementProposal, at time.Time) int {
 // PlacementAsk is the authorising ask about a proposal (§5): an Approve that binds its act, so only a channel that
 // proves who answered takes it, with the brief of the verdict by node (judge.Brief) as its explanation.
 func PlacementAsk(key string, p delivery.PlacementProposal, brief string, asking int, now time.Time) (delivery.AssignerAsk, error) {
-	binds, err := asks.ActDigest(PlacementAct(p))
+	binds, err := occ.ActDigest(PlacementAct(p))
 	if err != nil {
 		return delivery.AssignerAsk{}, err
 	}
 	nodes := p.Nodes()
 	headline := fmt.Sprintf("Change placement on %s?", strings.Join(nodes, ", "))
-	if p.Seed {
-		headline = "Take placement over from the controller?"
-	}
-	if n := len([]rune(headline)); n > asks.HeadlineLength {
+	if n := len([]rune(headline)); n > occ.HeadlineLength {
 		headline = fmt.Sprintf("Change placement on %d machines?", len(nodes))
 	}
-	return delivery.AssignerAsk{Ask: asks.Ask{
+	return assignerAsk(asking, oc.Ask{
 		ID:          delivery.AskingID(key, asking),
 		Headline:    headline,
 		Explanation: brief,
-		Options: []asks.Option{
+		Options: []oc.Option{
 			{ID: OptionYes, Label: "Approve", Does: "the placement of " + strings.Join(nodes, ", ") + " is written as proposed",
-				Level: asks.Approve, Binds: binds},
-			{ID: OptionNo, Label: "Decline", Does: "nothing is written, and the proposal ends", Level: asks.Acknowledge},
+				Level: occ.Approve, Binds: binds},
+			{ID: OptionNo, Label: "Decline", Does: "nothing is written, and the proposal ends", Level: occ.Acknowledge},
 		},
-		Who:      asks.Operator,
-		Expires:  now.Add(asks.ApproveLasts),
+		Who:      occ.Operator,
+		Expires:  occ.FormatTime(now.Add(occ.ApproveLasts)),
 		OnExpiry: "nothing is written, and the proposal ends",
 		About:    key,
-	}, Asking: asking}, nil
-}
-
-// ExportOf reads the controller's answer to placement-export (§7): its verb answers what the command printed, the
-// JSON of every node's placement, in `output` (the controller's verbAnswer; `answer` when it carries it as data). A
-// refused or unreadable answer is an error naming it.
-func ExportOf(raw []byte) (map[string]delivery.Placement, error) {
-	var a struct {
-		Output string          `json:"output"`
-		OK     *bool           `json:"ok"`
-		Answer json.RawMessage `json:"answer"`
-	}
-	if err := json.Unmarshal(raw, &a); err != nil {
-		return nil, fmt.Errorf("the controller's placement-export answered no verb answer: %w", err)
-	}
-	if a.OK != nil && !*a.OK {
-		return nil, fmt.Errorf("the controller's placement-export refused: %s", strings.TrimSpace(a.Output))
-	}
-	var byNode map[string]json.RawMessage
-	if len(a.Answer) > 0 && string(a.Answer) != "null" {
-		if err := json.Unmarshal(a.Answer, &byNode); err != nil {
-			return nil, fmt.Errorf("the controller's placement-export is no placement by node: %w", err)
-		}
-	} else if err := json.NewDecoder(strings.NewReader(a.Output)).Decode(&byNode); err != nil {
-		// The command prints its JSON first; what its standard error said after it is left.
-		return nil, fmt.Errorf("the controller's placement-export printed no placement by node: %w", err)
-	}
-	out := map[string]delivery.Placement{}
-	for node, rawP := range byNode {
-		p, err := delivery.DecodePlacement(rawP)
-		if err != nil {
-			return nil, fmt.Errorf("the controller's placement-export of %s cannot be read: %w", node, err)
-		}
-		if p.Node != node {
-			return nil, fmt.Errorf("the controller's placement-export names %s under %s", p.Node, node)
-		}
-		out[node] = p
-	}
-	if len(out) == 0 {
-		return nil, fmt.Errorf("the controller's placement-export names no node")
-	}
-	return out, nil
-}
-
-// SeedChanges is the seed's changes: every node's placement of the export, whole, in node order.
-func SeedChanges(export map[string]delivery.Placement) []delivery.PlacementProposalChange {
-	var out []delivery.PlacementProposalChange
-	for _, node := range sortedKeys(export) {
-		p := export[node]
-		out = append(out, delivery.PlacementProposalChange{Op: delivery.OpSeed, Node: node, Whole: &p})
-	}
-	return out
+	}), nil
 }
 
 // Rest is what a proposal leaves to write once the keys of written are: its changes of the other nodes, to be laid again

modules/mesh-delivery-assigner/internal/assign/seat_test.go

@@ -7,7 +7,7 @@ import (
 	"testing"
 	"time"
 
-	"git.novox.be/novox/mesh-sdk/go/asks"
+	occ "git.novox.be/novox/mesh-contracts/go/clients/operatorchannelclient"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
 )
 
@@ -37,41 +37,37 @@ func TestThePlacementSeatDecides(t *testing.T) {
 		in   ProposeIn
 		want string
 	}{
-		"a port before the lease": {in(delivery.PlacementProposalChange{Op: delivery.OpPlace, Node: "laptop", Module: "web", Ports: map[string]int{"80": 8080}}), "lease write"},
-		"a holding":               {in(delivery.PlacementProposalChange{Op: delivery.OpHold, Node: "anchor", Module: "store", Claim: "mesh-store", Scope: "mesh"}), "lease write"},
-		"a binding":               {in(delivery.PlacementProposalChange{Op: delivery.OpPlace, Node: "laptop", Module: "web", Bindings: map[string]delivery.Provider{"db": {Node: "anchor", Module: "store"}}}), "lease write"},
-		"a config place":          {in(delivery.PlacementProposalChange{Op: delivery.OpConfig, Node: "anchor", Module: "web", Layer: map[string]any{"places": []any{}}}), "lease write"},
-		"a config access":         {in(delivery.PlacementProposalChange{Op: delivery.OpConfig, Node: "anchor", Module: "web", MeshWide: map[string]any{"accesses": []any{}}}), "lease write"},
-		"a module not held":       {in(delivery.PlacementProposalChange{Op: delivery.OpPlace, Node: "laptop", Module: "ghost"}), "the indexer holds no module ghost"},
-		"a node with no record":   {in(delivery.PlacementProposalChange{Op: delivery.OpPlace, Node: "stranger", Module: "web"}), "stranger is a node with no record"},
-		"nothing changes":         {in(delivery.PlacementProposalChange{Op: delivery.OpPlace, Node: "anchor", Module: "web"}), "leave every placement as it is"},
-		"no why":                  {func() ProposeIn { i := in(move...); i.Why = " "; return i }(), "says why"},
-		"no caller":               {func() ProposeIn { i := in(move...); i.By = ""; return i }(), "names no caller"},
-		"a seed by hand":          {in(delivery.PlacementProposalChange{Op: delivery.OpSeed, Node: "laptop", Whole: &laptop}), "adopt's alone"},
-		"a pin of nobody placed":  {in(delivery.PlacementProposalChange{Op: delivery.OpPin, Node: "laptop", Provision: "db", Provider: &delivery.Provider{Node: "laptop", Module: "store"}}), "not placed there"},
+		"a module not held":     {in(delivery.PlacementProposalChange{Op: delivery.OpPlace, Node: "laptop", Module: "ghost"}), "the indexer holds no module ghost"},
+		"a node with no record": {in(delivery.PlacementProposalChange{Op: delivery.OpPlace, Node: "stranger", Module: "web"}), "stranger is a node with no record"},
+		"nothing changes":       {in(delivery.PlacementProposalChange{Op: delivery.OpPlace, Node: "anchor", Module: "web"}), "leave every placement as it is"},
+		"no why":                {func() ProposeIn { i := in(move...); i.Why = " "; return i }(), "says why"},
+		"no caller":             {func() ProposeIn { i := in(move...); i.By = ""; return i }(), "names no caller"},
+		"a seed by hand":        {in(delivery.PlacementProposalChange{Op: delivery.OpSeed, Node: "laptop", Whole: &laptop}), "gone with adopt"},
+		// 1126: the controller ended by its unassignment; placed again it would be a second writer beside the parts that
+		// act without its lease.
+		"the controller placed again": {in(delivery.PlacementProposalChange{Op: delivery.OpPlace, Node: "laptop", Module: "mesh-controller"}), "ended by its unassignment"},
+		"the controller seeded whole": {in(delivery.PlacementProposalChange{Op: delivery.OpSeed, Node: "anchor", Whole: &delivery.Placement{V: delivery.Version, Node: "anchor",
+			Decided: anchor.Decided, Modules: []delivery.PlacedModule{{Module: "mesh-controller"}}}}), "two writers (issue 1126)"},
+		"a pin of nobody placed": {in(delivery.PlacementProposalChange{Op: delivery.OpPin, Node: "laptop", Provision: "db", Provider: &delivery.Provider{Node: "laptop", Module: "store"}}), "not placed there"},
 	} {
 		if _, _, f := Propose(c.in); !slices.ContainsFunc(f, func(s string) bool { return strings.Contains(s, c.want) }) {
 			t.Errorf("%s: findings %v, want one naming %q", name, f, c.want)
 		}
 	}
 
-	// A module's config values may be proposed before the lease write (§13); once the lease is written every change is
-	// the state's alone, and none waits.
-	if _, _, f := Propose(in(delivery.PlacementProposalChange{Op: delivery.OpConfig, Node: "anchor", Module: "web", Values: map[string]any{"puid": 1}})); len(f) != 0 {
-		t.Errorf("config values before the lease write: %v", f)
-	}
-	Leased = true
+	// Every kind of change is taken: the placement is the one source, and the controller's verbs limit nothing (ADR 0567 §8).
 	for _, c := range []delivery.PlacementProposalChange{
+		{Op: delivery.OpConfig, Node: "anchor", Module: "web", Values: map[string]any{"puid": 1}},
 		{Op: delivery.OpPlace, Node: "laptop", Module: "web", Ports: map[string]int{"80": 8080}, Bindings: map[string]delivery.Provider{"db": {Node: "anchor", Module: "store"}}},
 		{Op: delivery.OpConfig, Node: "anchor", Module: "web", Layer: map[string]any{"places": []any{}}},
+		{Op: delivery.OpConfig, Node: "anchor", Module: "web", MeshWide: map[string]any{"accesses": []any{}}},
 		{Op: delivery.OpDecide, Node: "laptop", Field: "site", Value: json.RawMessage(`"attic"`)},
 		{Op: delivery.OpHold, Node: "anchor", Module: "store", Claim: "node-shell", Scope: "node"},
 	} {
 		if _, _, f := Propose(in(c)); len(f) != 0 {
-			t.Errorf("after the lease write %s is refused: %v", c.Op, f)
+			t.Errorf("%s is refused: %v", c.Op, f)
 		}
 	}
-	Leased = false
 
 	// A key moved while the warrant wrote: what is left to write is the other nodes' changes, to be laid and asked again.
 	if rest, ok := Rest(p, map[string]*delivery.Placement{"anchor": laid["anchor"]}); !ok || len(rest.Changes) != 1 || rest.Changes[0].Node != "laptop" ||
@@ -85,73 +81,23 @@ func TestThePlacementSeatDecides(t *testing.T) {
 	// The seat says it waits while one of its states is not bound, naming it, and clears once all are.
 	for _, unbound := range [][]string{{delivery.PlacementPulsesBucket}, nil} {
 		c := SeatWaitsCondition(unbound)
-		if _, err := asks.EncodeCondition(c); err != nil || (len(unbound) > 0) != (c.State == asks.StateRaised) ||
+		if _, err := occ.EncodeCondition(c); err != nil || (len(unbound) > 0) != (c.State == occ.StateRaised) ||
 			(len(unbound) > 0 && !strings.Contains(c.Explanation, "the seat waits for its states: "+delivery.PlacementPulsesBucket)) {
 			t.Errorf("waiting for %v: %+v, %v", unbound, c, err)
 		}
 	}
 
-	// Issue 1126: the seed places the private network, which no repository holds; it is the mesh's own, and passes.
-	wired := laptop
-	wired.Modules = append(slices.Clone(laptop.Modules), delivery.PlacedModule{Module: "mesh-wireguard"})
-	seed := in(SeedChanges(map[string]delivery.Placement{"laptop": wired})...)
-	seed.Seed, seed.ExportDigest, seed.Current, seed.Revisions = true, "sha256:x", map[string]delivery.Placement{}, map[string]uint64{}
-	seed.Held = func(m string) bool { return m != "mesh-wireguard" } // the indexer holds every module but it
-	if _, _, f := Propose(seed); len(f) != 0 {
-		t.Errorf("a seed placing the private network is refused: %v", f)
-	}
-
 	writes, err := Writes(p, laid)
-	if err != nil || len(writes) != 2 || writes[0].Key != "placement.anchor" || writes[0].Base != 4 || writes[1].Base != 9 {
+	if err != nil || len(writes) != 2 || writes[0].Key != "anchor.node" || writes[0].Base != 4 || writes[1].Base != 9 {
 		t.Fatalf("writes = %+v, %v", writes, err)
 	}
-	pinned := *laid["laptop"]
-	pinned.Pins = map[string]delivery.Provider{"db": {Node: "anchor", Module: "store"}}
-	calls := ControllerCalls(map[string]delivery.Placement{"anchor": anchor, "laptop": laptop},
-		map[string]*delivery.Placement{"anchor": laid["anchor"], "laptop": &pinned}, "p-one", "w1@t")
-	var said []string
-	for _, c := range calls {
-		said = append(said, c.Key())
-		if !strings.Contains(c.Args["why"].(string), "p-one") {
-			t.Errorf("%s does not name the proposal: %v", c.Key(), c.Args)
-		}
-	}
-	if !slices.Equal(said, []string{"mesh-controller.unassign anchor web", "mesh-controller.assign laptop web", "mesh-controller.pin laptop db"}) {
-		t.Errorf("the controller's calls = %v", said)
-	}
-
 	a, err := PlacementAsk("placement.p-one", p, "move web (proposed by operator@laptop)", 7, time.Unix(100, 0))
-	if err != nil || a.Ask.Check(time.Unix(100, 0)) != nil || a.Ask.Options[0].Level != asks.Approve || a.Ask.Options[0].Performs(PlacementAct(p)) != nil {
+	if err != nil || occ.Check(mustAsk(t, a), time.Unix(100, 0)) != nil || mustAsk(t, a).Options[0].Level != occ.Approve || occ.Performs(mustAsk(t, a).Options[0], PlacementAct(p)) != nil {
 		t.Fatalf("the ask = %+v, %v", a, err)
 	}
 	q := p
 	q.Changes = append(slices.Clone(p.Changes), delivery.PlacementProposalChange{Op: delivery.OpUnpin, Node: "laptop", Provision: "x"})
-	if a.Ask.Options[0].Performs(PlacementAct(q)) == nil {
+	if occ.Performs(mustAsk(t, a).Options[0], PlacementAct(q)) == nil {
 		t.Error("the ask's yes binds changes it was not asked about")
 	}
-
-	export, _ := json.Marshal(map[string]any{"anchor": anchor, "laptop": laptop})
-	for name, c := range map[string]struct {
-		raw  string
-		want int
-	}{
-		"in output":  {`{"ok":true,"output":` + quote(string(export)+"\n") + `}`, 2},
-		"as answer":  {`{"ok":true,"output":"","answer":` + string(export) + `}`, 2},
-		"refused":    {`{"ok":false,"output":"no store"}`, 0},
-		"no node":    {`{"ok":true,"output":"{}"}`, 0},
-		"no version": {`{"ok":true,"output":"{\"anchor\":{\"node\":\"anchor\",\"modules\":[]}}"}`, 0},
-	} {
-		got, err := ExportOf([]byte(c.raw))
-		if len(got) != c.want || (c.want == 0) != (err != nil) {
-			t.Errorf("%s: %d nodes, %v", name, len(got), err)
-		}
-	}
-	if seed := SeedChanges(map[string]delivery.Placement{"laptop": laptop, "anchor": anchor}); len(seed) != 2 || seed[0].Node != "anchor" || seed[0].Op != delivery.OpSeed {
-		t.Errorf("the seed's changes = %+v", seed)
-	}
-}
-
-func quote(s string) string {
-	raw, _ := json.Marshal(s)
-	return string(raw)
 }

modules/mesh-delivery-assigner/internal/assign/verbs.go

@@ -0,0 +1,38 @@
+package assign
+
+import (
+	"slices"
+
+	"git.novox.be/novox/mesh-delivery/sdk/graph"
+)
+
+// verbWaiting says why the module's want on node waits for a verb it invokes (novox/hq ADR 0614 §2): the first seat verb or
+// module tool of Invokes (the module graph's verb edges, those it leaves out on a cycle not among them, §3) that no
+// running healthy build serves. Nil Served (nothing read of what runs) waits for none, and a verb a running build serves
+// already adds no wait. It holds under the provisions' rule (RuleProvisions): no reader knows a rule number of its own
+// yet, so the words name the edge (graph.VerbWaitWords, which the delivery view reads).
+func (m Module) verbWaiting(node string) (string, bool) {
+	if m.Served == nil {
+		return "", false
+	}
+	for _, v := range slices.Sorted(slices.Values(m.Invokes)) {
+		if !m.Served(v) {
+			return graph.VerbWaitWords(v, m.Name, node), true
+		}
+	}
+	return "", false
+}
+
+// busStateWaiting says why the module's want on node waits for bus state (ADR 0614 §5): its manifest asks bus state (a
+// bus-state entry, as the module graph reads it) and no build whose manifest offers bus-state runs healthy on a node
+// present. The provision bus-state is answered with no credential of a consumer's own, so ADR 0603 §5 counts the
+// provider's own have and no provisioner key is waited for, handed or not. Nil Offering (nothing read of what runs) waits
+// for none, and neither does a module that offers bus-state itself. It holds under the provisions' rule, its words naming bus state (graph.BusStateWaitWords).
+func (m Module) busStateWaiting(node string) (string, bool) {
+	if len(m.Manifest.BusState) == 0 || m.Offering == nil || m.Offering(graph.BusState) ||
+		slices.Contains(m.Manifest.Offers(), graph.BusState) { // the bus module offering it waits on nobody for it
+
+		return "", false
+	}
+	return graph.BusStateWaitWords(m.Name, node), true
+}

modules/mesh-delivery-assigner/internal/assign/wants.go

@@ -10,6 +10,10 @@ import (
 
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/provisions"
+
+	"git.novox.be/novox/mesh-delivery/sdk/forms"
+	"git.novox.be/novox/mesh-delivery/sdk/graph"
 )
 
 // Module is what the six rules read of one module (ADR 0429 §6, ADR 0528 clause 3): its newest fingerprint F at the
@@ -29,13 +33,40 @@ type Module struct {
 	// 1945, live on 2026-10-25 at 20:04: ace's mesh-build-go was wanted with no account on the bus). Nil: the grant alone.
 	GrantedOn func(node string) bool
 	Manifest  catalogue.Manifest
-	Nodes     []string
-	// Composed answers the controller's composition of the module for a node at a fingerprint (mesh-controller_composed): its
-	// digest and the judgement of the move to it, and whether it exists. Nil: none exists (ADR 0539 §1, §6).
+	// Provisions is the seat mesh-provisioner's provisions this module consumes on a node, by key (ADR 0570 §4): the want
+	// waits until each is provided. Nil: the seat's state is not read (not delivered yet), and nothing waits on it.
+	Provisions func(node string) map[string]provisions.Provision
+	// Answering is the manifests of the modules placed somewhere that provide a provision: what catalogue.Awaited
+	// judges a want's provisions by (issue 774). Nil: none known, and no key is waited for that is not there.
+	Answering func(provision string) []catalogue.Manifest
+	// Offered says whether any module offers a provision by name or by its own name (catalogue.Manifest.Offers) among every
+	// manifest the trunk holds and the modules the mesh provides itself, placed or not. Nil: not known, and no requirement
+	// is waited on for want of an offer.
+	Offered func(provision string) bool
+	// Invokes are the seat verbs and module tools the module graph says the module invokes and keeps as edges to the
+	// modules serving them, those it leaves out on a cycle not among them (ADR 0614 §2, §3): the want waits until each is
+	// served (Served). Nil: no graph node is read, and no want waits on a verb.
+	Invokes []string
+	// Served says whether a build serving a seat verb or module tool runs healthy, counted from its holder's have (ADR 0614
+	// §2, as ADR 0603 §5 counts a provider's). Nil: nothing is read of what runs, and no want waits on a verb.
+	Served func(invoke string) bool
+	// Offering says whether a build whose manifest offers a provision runs healthy on a node present, counted from the
+	// provider's own have (ADR 0603 §5): what a want asking bus state waits for (ADR 0614 §5). Nil: nothing is read of what
+	// runs, and no want waits on bus state.
+	Offering func(provision string) bool
+	// Chosen is a person's choice of the module's upgrade policy (the assigner's `policies`, ADR 0565 §7); nil: none.
+	Chosen *catalogue.PersonPolicy
+	Nodes  []string
+	// Composed answers the composition of the module for a node at a fingerprint: the digest the node's own have names (a
+	// placed node composes its own, ADR 0571 §6), and whether it names one. Nil: none exists (ADR 0539 §1, §6).
 	Composed func(node, fp string) (delivery.ComposedDigest, bool)
 	// Allowed says whether the operator answered yes to the record ask about the move of this module on node to the composition
 	// with this digest (ADR 0539 §14). Nil: none did.
 	Allowed func(node, digest string) bool
+	// Release names the release whose Approve carries the build fp, as mesh-delivery's gate holds it for the release's heads,
+	// read by the build's source revision (ADR 0601 §1): that Approve is the yes to a move of the build alone. False when no
+	// approved release is known to carry it. Nil: none is read.
+	Release func(fp string) (string, bool)
 	// Released is a hold on FP the operator released (ADR 0539 §19): FP is not held again by a health check that failed.
 	Released bool
 	// Restored says whether the operator answered "restore" to the restore ask of this data module on node: it is then set back
@@ -47,6 +78,13 @@ type Module struct {
 	Now time.Time
 	// Puts are the puts of the module, by node (ADR 0546): while one owns a node's want (PutOwns), the rules pass over it.
 	Puts map[string]delivery.Put
+	// Needs are the reader capabilities the manifest at FP needs (the indexer's modules value, catalogue.ManifestNeeds, ADR
+	// 0614 §4): a node's want moves only while that node's engine states each of them. Nil: none.
+	Needs []string
+	// FormNeeds are the reference forms the module's build at FP is written in (`form:<name>`, the builder's build key's
+	// needs, ADR 0618 §1): a node's want is held only while that node's engine reads none of them (ADR 0624 §2). Nil: the
+	// build names none, and holds nothing.
+	FormNeeds []string
 	// Self says whether node composes the module itself: the catalogue's placement names the node (ADR 0547 §2). It is the one
 	// source of a want's Self: every want the rules write or keep is derived from it (selfDerived), so a want written Self while
 	// the node was placed does not outlive the placement (issue 1126). Nil: no node does.
@@ -68,6 +106,9 @@ type Nodes struct {
 	Haves  map[string]map[string]delivery.Have
 	// Providers is, by provision, the modules that provide it, with the nodes each is assigned to.
 	Providers map[string]map[string][]string
+	// Reads is, by node, the reader capabilities its node-engine states in its node record (delivery.NodeRecord.ManifestReads,
+	// ADR 0614 §4). A node with none, or none read, is read as stating the baseline (catalogue.StatedManifestReads).
+	Reads map[string][]string
 }
 
 // healthy says whether a have runs fp healthy.
@@ -89,14 +130,15 @@ func Canary(nodes []string, online map[string]bool) string {
 
 // Holds is whether every rule holds for moving node's want for m to m.FP, and if not, the first rule that does not,
 // with why (ADR 0429 §6). Rule 4, at most `step` others ahead, always holds: the mesh keeps no step, and step 0 is no
-// limit (ADR 0528 clause 3).
+// limit (ADR 0528 clause 3). Rule 5, every provider healthy, holds no want (issue 1960): a module whose provider is down
+// is wanted all the same, and said as not reached (Unreached), since a site runs while the proxy in front of it is
+// down and one module never blocks another.
 func Holds(m Module, node string, n Nodes) (bool, int, string) {
 	return holds(m, node, n, true)
 }
 
-// holds is Holds; with ordering false it leaves out the two rules that order a move among nodes and modules, the canary (3)
-// and the providers (5), and keeps those without which there is nothing to want: the build done, not held, the grant and the
-// composition.
+// holds is Holds; with ordering false it leaves out the canary (3), which orders a move among nodes, and keeps those
+// without which there is nothing to want: the build done, not held, the grant and the composition.
 func holds(m Module, node string, n Nodes, ordering bool) (bool, int, string) {
 	switch {
 	case !m.Built:
@@ -112,11 +154,6 @@ func holds(m Module, node string, n Nodes, ordering bool) (bool, int, string) {
 		case node != canary && !healthy(n.Haves[canary][m.Name], m.FP):
 			return false, delivery.RuleCanary, fmt.Sprintf("the canary %s does not run %s healthy yet", canary, short(m.FP))
 		}
-		for _, provision := range m.Manifest.Requires {
-			if ok, why := providedHealthy(provision, node, n); !ok {
-				return false, delivery.RuleProviders, why
-			}
-		}
 	}
 	if !m.Granted {
 		return false, delivery.RuleGrant, fmt.Sprintf("the controller has not issued the credential of %s for %s", m.Name, short(m.FP))
@@ -125,12 +162,114 @@ func holds(m Module, node string, n Nodes, ordering bool) (bool, int, string) {
 		return false, delivery.RuleGrant, fmt.Sprintf("the controller has not issued the credential of %s on %s for %s", m.Name, node,
 			short(m.FP))
 	}
+	if words, lacking := m.readerLacking(node, n); lacking {
+		return false, delivery.RuleComposed, words
+	}
 	if _, ok := m.composition(node, m.FP); !ok {
-		return false, delivery.RuleComposed, fmt.Sprintf("the controller has not composed %s for %s at %s", m.Name, node, short(m.FP))
+		return false, delivery.RuleComposed, fmt.Sprintf("%s has named no composition of its own for %s at %s yet", node, m.Name, short(m.FP))
+	}
+	if words, waiting := m.provisionWaiting(node); waiting {
+		return false, delivery.RuleProvisions, words
+	}
+	if words, waiting := m.verbWaiting(node); waiting {
+		return false, delivery.RuleProvisions, words
+	}
+	if words, waiting := m.busStateWaiting(node); waiting {
+		return false, delivery.RuleProvisions, words
 	}
 	return true, 0, ""
 }
 
+// readerLacking says why the module's want on node is held for the node's engine (ADR 0614 §4): a reader capability its
+// manifest needs that the engine does not state, read as the baseline when it states none. It is held under rule 7 (the
+// composition), since no rule of its own is numbered in this release, with words naming the capability; it moves once the
+// engine states it. The node-engine's own new build is held only by a word of its own manifest no engine states.
+//
+// A build's reference forms hold the want only when the engine reads none of them (ADR 0624 §2): every engine reads a
+// first form, so a build written in one is never held by its forms; the words name the forms it reads none of.
+func (m Module) readerLacking(node string, n Nodes) (string, bool) {
+	missing := catalogue.MissingManifestReads(m.Needs, n.Reads[node])
+	if len(missing) == 0 && forms.Current.Held(m.FormNeeds, n.Reads[node]) {
+		missing = slices.Clone(m.FormNeeds)
+	}
+	if len(missing) == 0 {
+		return "", false
+	}
+	return graph.ReaderWaitWords(node, missing, m.Name, short(m.FP)), true // the words the delivery view names the edge by
+}
+
+// provisionWaiting says why the module's want on node waits for a provision (ADR 0570 §4): a provision it requires that has
+// no key yet, or the first of its keys that is not provided. Nil Provisions (the seat's state not on the bus) waits for none.
+func (m Module) provisionWaiting(node string) (string, bool) {
+	if m.Provisions == nil {
+		return "", false
+	}
+	if missing := m.MissingProvisions(node); len(missing) > 0 {
+		return fmt.Sprintf("provision %s has no key yet for %s on %s", missing[0], m.Name, node), true
+	}
+	keyed := m.Provisions(node)
+	// Only a provision the newest manifest still requires is waited on (ADR 0603 §9): a key of an older revision's edge,
+	// asked or retiring for the operator's answer (ADR 0570 §5), holds nothing. A requirement catalogue.Awaited leaves out is
+	// not waited on when something offers it (a module's own name, a module the mesh provides itself, a provision the
+	// composition does not key: optional, a toolchain on the module's own machine, a login the controller makes). One that
+	// nothing offers is waited on (ADR 0603 §5: an unknown provider has provided nothing), so a consumer never moves ahead of
+	// a provider whose module the indexer has not yet taken in; it holds loudly, since the watchman raises the hold past its
+	// bound (ADR 0603 §8).
+	needed := m.Manifest.Requires
+	if m.Answering != nil {
+		needed = catalogue.Awaited(m.Manifest, m.Answering)
+		have := map[string]bool{}
+		for _, p := range keyed {
+			have[p.Provision] = true
+		}
+		for _, r := range slices.Sorted(slices.Values(m.Manifest.Requires)) {
+			if have[r] && !m.Manifest.OptionalRequires[r] && !slices.Contains(needed, r) {
+				needed = append(needed, r) // the provisioner keys it from the manifests, whoever is placed yet
+				continue
+			}
+			if m.Offered == nil || m.Manifest.OptionalRequires[r] || len(m.Answering(r)) > 0 || m.Offered(r) || slices.Contains(needed, r) {
+				continue
+			}
+			needed = append(needed, r)
+			if !have[r] {
+				return fmt.Sprintf("no module offers %s yet for %s on %s: an unknown provider has provided nothing, so the want waits for one, and the watchman raises it past its bound", r, m.Name, node), true
+			}
+		}
+	}
+	for _, key := range slices.Sorted(maps.Keys(keyed)) {
+		if p := keyed[key]; p.State != provisions.Provided && slices.Contains(needed, p.Provision) {
+			words := fmt.Sprintf("the provision %s of %s on %s is %s, not provided", key, m.Name, node, p.State)
+			if p.Why != "" {
+				words += ": " + p.Why
+			}
+			return words, true
+		}
+	}
+	return "", false
+}
+
+// MissingProvisions are the provisions a want of the module waits for (catalogue.Awaited, the one rule the plan
+// composition and the seat mesh-provisioner key by, issue 774) that have no key on node yet, sorted; none while the
+// seat's state is not read. A requirement the composition keys nothing for (a toolchain on the module's own machine, a
+// login the controller still makes for a module not handed) is not waited for: on 2026-10-30 every new build of
+// grafana, dnsmasq, mesh-knowledge, mesh-mail and the builders waited here for a key nobody would make.
+func (m Module) MissingProvisions(node string) []string {
+	if m.Provisions == nil || m.Answering == nil {
+		return nil
+	}
+	have := map[string]bool{}
+	for _, p := range m.Provisions(node) {
+		have[p.Provision] = true
+	}
+	var out []string
+	for _, r := range catalogue.Awaited(m.Manifest, m.Answering) {
+		if !have[r] {
+			out = append(out, r)
+		}
+	}
+	return out
+}
+
 // providedHealthy is rule 5 for one provision: some module providing it runs healthy on the node, or, assigned
 // elsewhere only, at its canary. A provision no module provides is not a module's to judge (the mesh or the node
 // offers it) and holds.
@@ -157,6 +296,17 @@ func providedHealthy(provision, node string, n Nodes) (bool, string) {
 	return false, fmt.Sprintf("no provider of %s runs healthy on %s or at its canary", provision, node)
 }
 
+// unreached is why m on node may be wanted and not reached: the first provision it requires that no provider runs
+// healthy on node or at its canary (rule 5, said and never holding a want; issue 1960); empty when all do.
+func unreached(m Module, node string, n Nodes) string {
+	for _, provision := range m.Manifest.Requires {
+		if ok, why := providedHealthy(provision, node, n); !ok {
+			return why
+		}
+	}
+	return ""
+}
+
 // keepsData says whether a module holds data a set-back would lose: an own item of a class that keeps (irreplaceable,
 // valuable or rebuildable; cache and none do not).
 func keepsData(m catalogue.Manifest) bool {
@@ -186,6 +336,9 @@ type Outcome struct {
 	Restore []string
 	// Rules is, by node, the rule holding the node back from m.FP and why.
 	Rules map[string]Holding
+	// Unreached is, by node, why the module may be wanted there and not reached: no provider of a provision it requires runs
+	// healthy (rule 5, issue 1960). It holds no want back; the pass says it.
+	Unreached map[string]string
 	// Neither is, by node, the nodes the module is assigned to that run it (or whose have names it), hold no want for it after this
 	// pass and are not held (a held module is on the held list), with the rule holding the first want back: the node's own composition does not hold a module with a fingerprint of the new form, so such a module is on
 	// neither list and nothing applies it on that node (issue 1945). A module with no fingerprint of the new form goes with the node's
@@ -202,29 +355,18 @@ type RecordNeed struct {
 	Words     string
 }
 
-// Holding is a rule holding a node back, and why. Bus marks the bar on the bus instead of one of the seven rules (Rule is then
-// 0): the bus moves only by the operator's put (ADR 0539 §15, ADR 0546 §8), never by the assigner (issue 1945: nats on novox,
-// running an old-form build, got no want and the pass said nothing).
+// Holding is a rule holding a node back, and why. The bus module is held back by the rules alone, as every module (ADR 0601 §1,
+// §2): no bar of its own.
 type Holding struct {
 	Rule  int
 	Words string
-	Bus   bool
 }
 
-// Reason is the holding in words: the rule and its words, or for the bus bar its words alone.
+// Reason is the holding in words: the rule and its words.
 func (h Holding) Reason() string {
-	if h.Bus {
-		return h.Words
-	}
 	return fmt.Sprintf("rule %d: %s", h.Rule, h.Words)
 }
 
-// BusBarWords say why the assigner writes no want moving the bus on node: it runs prev, the trunk builds fp, and only the
-// operator's put moves it (ADR 0539 §15, ADR 0546 §8). The words reach the operator, so they name no record.
-func BusBarWords(node, prev, fp string) string {
-	return fmt.Sprintf("only your put moves the bus: %s runs %s, the trunk builds %s; put it with assigner_put", node, short(prev), short(fp))
-}
-
 // Wants is the pass of one module m: for each of its nodes, the want by the six rules, starting from the want written
 // before (wants, by node); lastHealthy is, by node, the newest fingerprint other than m.FP the node ran healthy. A failed
 // health check of m.FP on a node holds it: every node wanting m.FP is set back to its last healthy fingerprint, but a
@@ -301,26 +443,33 @@ func Wants(m Module, n Nodes, wants map[string]delivery.Want, lastHealthy map[st
 		}
 		ok, rule, words := Holds(mm, node, n)
 		target := m.FP
-		if have, ran := n.Haves[node][m.Name]; !ok && (!had || before.Removed) && (rule == delivery.RuleCanary || rule == delivery.RuleProviders) && runs(have) {
-			// A node that runs the module and has no want for it has no want the ordering rules could hold it back to: holding its first
-			// want back leaves the module on neither list, since the node's own composition gives up every module with a fingerprint of
-			// the new form (issue 1945: on g14 the bundles of clipmenu, screen-lock and every module requiring x11-display were removed
-			// and never made again, because xorg's health is unknown and screen-lock's canary never ran it healthy). Its first want names
-			// what it runs, never a newer fingerprint, so the canary is never passed over: F when it runs F (by the rules without which
-			// there is nothing to want), or an older fingerprint of the new form whose composition and grant exist. Rules 3 and 5 then
-			// order the move from it as from any want.
-			switch _, composed := m.composition(node, have.FP); {
-			case !ran:
-			case have.FP == m.FP:
-				ok, rule, words = holds(mm, node, n, false)
-			case !strings.HasPrefix(have.FP, delivery.SourcePrefix2):
-				// An old-form build (not src2:) has no composition, so no want can ever name it: its first want names F, and only by every
-				// rule as usual, the canary (3) and the providers (5) included, which here hold it back. Nothing is written and the module
-				// stays on neither list until the canary runs F healthy; then Holds passes and the want names F (issue 1945, a design
-				// limit set by the lead: the canary stays in force and old-form modules leave neither list by themselves).
-			case composed && m.GrantedAt != nil && m.GrantedAt(have.FP):
-				ok, target = true, have.FP
+		if have, ran := n.Haves[node][m.Name]; !ok && (!had || before.Removed) && rule == delivery.RuleCanary {
+			// The canary orders a move, never the first want of a node that does not run the module (issue 1960: de-spiegel,
+			// link2pay and photos on novox were left with no want). A node that runs an older fingerprint of the new form,
+			// composed and granted, gets its first want at what it runs, and rule 3 then orders its move to F as from any want.
+			// A node that runs an old-form build, which no want can name, stays under the canary (issue 1945, a design limit):
+			// its first want names F once the canary runs F healthy. Any other node that runs it (F itself, or an older
+			// fingerprint with no composition or grant) gets F by the rules without which there is nothing to want.
+			older := ran && runs(have) && have.FP != m.FP && strings.HasPrefix(have.FP, delivery.SourcePrefix2)
+			if older {
+				_, composed := m.composition(node, have.FP)
+				older = composed && m.GrantedAt != nil && m.GrantedAt(have.FP)
 			}
+			oldForm := ran && runs(have) && have.FP != m.FP && !strings.HasPrefix(have.FP, delivery.SourcePrefix2)
+			switch {
+			case older:
+				ok, target = true, have.FP
+			case oldForm:
+				// held back by rule 3 as written: on neither list until the canary runs F healthy
+			default:
+				ok, rule, words = holds(mm, node, n, false)
+			}
+		}
+		if why := unreached(m, node, n); why != "" {
+			if out.Unreached == nil {
+				out.Unreached = map[string]string{}
+			}
+			out.Unreached[node] = why
 		}
 		if ok && target == m.FP && len(out.NodeFailed) > 0 && !(had && !before.Removed && before.FP == m.FP) &&
 			n.Haves[node][m.Name].FP != m.FP {
@@ -339,7 +488,8 @@ func Wants(m Module, n Nodes, wants map[string]delivery.Want, lastHealthy map[st
 				next.Newest, next.Rule, next.Words = m.FP, rule, words
 				at.FP = target
 			}
-			if had && !before.Removed && !before.Put && before.FP == target && before.Composed == d.Digest {
+			// A placed node's want names the build alone: it is the same target while the build is.
+			if had && !before.Removed && !before.Put && before.FP == target && (before.Composed == d.Digest || (before.Self && m.selfOn(node))) {
 				next.Backup, next.Words = before.Backup, before.Words // the answer to a failed backup stays while its target stays (ADR 0539 §16)
 			}
 			running, ran := n.Haves[node][m.Name]
@@ -351,14 +501,6 @@ func Wants(m Module, n Nodes, wants map[string]delivery.Want, lastHealthy map[st
 			if need, wait := at.mustAsk(node, asked, hadLive, ran, running.FP, running.Composed == "", d); wait {
 				if need != nil {
 					out.Record = append(out.Record, *need)
-				} else if prev, barred := at.busBar(asked, hadLive, running.FP); barred {
-					// The bus is barred: no want moves it but the operator's put. Said, never silent (issue 1945): its holding is named,
-					// and a node that runs it with no live want has it on neither list, so its condition stays raised.
-					h := Holding{Bus: true, Words: BusBarWords(node, prev, at.FP)}
-					out.Rules[node] = h
-					if !hadLive && running.Phase != delivery.PhaseRemoved && !held {
-						out.Neither[node] = h
-					}
 				}
 				continue
 			}
@@ -461,7 +603,7 @@ func (m Module) selfDerived(node string, before delivery.Want, had bool, next de
 	d, there := m.composition(node, next.FP)
 	if !there || d.Digest == "" {
 		out.Rules[node] = Holding{Rule: delivery.RuleComposed, Words: fmt.Sprintf("%s on %s was composed by the node while it was placed, "+
-			"and the controller has not composed it at %s, so its want stays", m.Name, node, short(next.FP))}
+			"and no composition of its own is named at %s now, so its want stays", m.Name, node, short(next.FP))}
 		return next, false
 	}
 	at := m
@@ -585,10 +727,10 @@ func short(fp string) string {
 	return part[:12]
 }
 
-// mustAsk says whether the move to the composition d on node waits: for the operator's yes (need names the ask) or, for the bus,
-// for the operator's hand (ADR 0539 §14, §15). A module the node never ran (it has no want and no have), a move judged neither, a module that is not of
-// policy record and a want that stays are written as any want; so is a revision of the bus module's composition at the
-// same fingerprint judged neither (a user list only, §7).
+// mustAsk says whether the move to the composition d on node waits for the operator's yes (need names the ask, ADR 0539 §14). A
+// module the node never ran (it has no want and no have), a move judged neither, a module that is not of policy record and a want
+// that stays are written as any want. The bus module is no exception: it moves by the rules (ADR 0601 §1), its node backing up its
+// streams before it applies (§2); the assigner asks no snapshot for it.
 func (m Module) mustAsk(node string, before delivery.Want, had, ran bool, running string, haveNamesNoComposition bool, d delivery.ComposedDigest) (*RecordNeed, bool) {
 	if (!had && !ran) || before.Removed || (before.FP == m.FP && before.Composed == d.Digest) {
 		return nil, false
@@ -600,9 +742,6 @@ func (m Module) mustAsk(node string, before delivery.Want, had, ran bool, runnin
 	if !had && ran && running == m.FP && haveNamesNoComposition && d.Judgement == delivery.JudgedUnchanged {
 		return nil, false
 	}
-	if _, barred := m.busBar(before, had, running); barred {
-		return nil, true // the bus is never moved by the assigner; the operator writes its want (§15)
-	}
 	if !m.recorded(d) || d.Judgement == delivery.JudgedNeither || d.Judgement == delivery.JudgedUnchanged {
 		return nil, false
 	}
@@ -612,19 +751,14 @@ func (m Module) mustAsk(node string, before delivery.Want, had, ran bool, runnin
 	return &RecordNeed{Node: node, Digest: d.Digest, Judgement: d.Judgement, Words: d.Words}, true
 }
 
-// busBar says whether m is the bus and the move would take it off the fingerprint it ran before, prev: its want's, or with no
-// readable want the one its have names (ADR 0539 §15 bars a new one).
-func (m Module) busBar(before delivery.Want, had bool, running string) (prev string, barred bool) {
-	prev = before.FP
-	if !had {
-		prev = running
-	}
-	return prev, catalogue.ProvidesBus(m.Manifest) && prev != m.FP
-}
-
-// recorded says whether the module is of policy record: as the controller holds it beside the composition's digest, the
-// operator's own choice included (ADR 0539 §14); on a composition made by hand, which carries none, as the manifest derives it.
+// recorded says whether the module is of policy record: a person's choice at the assigner over the manifest's word (ADR
+// 0565 §7, catalogue.Upgrade); for a module with none, as the controller holds it beside the composition's digest until the
+// lease write (ADR 0539 §14); on a composition made by hand, which carries none, as the manifest derives it.
 func (m Module) recorded(d delivery.ComposedDigest) bool {
+	if m.Chosen != nil {
+		policy, _, _, _ := catalogue.Upgrade(m.Manifest, m.Chosen)
+		return policy == catalogue.PolicyRecord
+	}
 	if d.Policy != "" {
 		return d.Policy == delivery.PolicyRecord
 	}
@@ -654,8 +788,8 @@ func (m Module) userListRevision(node string, before delivery.Want, had bool, n
 	return w, true
 }
 
-// GrantNamesNode says whether a grant of module names its accounts on node (mesh-sdk's ControllerGrant.NamesNode, which a
+// GrantNamesNode says whether a grant of module names its accounts on node (mesh-sdk's Grant.NamesNode, which a
 // put reads by too).
-func GrantNamesNode(g delivery.ControllerGrant, node, module string) bool {
+func GrantNamesNode(g delivery.Grant, node, module string) bool {
 	return g.NamesNode(node, module)
 }

modules/mesh-delivery-assigner/internal/assign/wants_test.go

@@ -8,6 +8,9 @@ import (
 
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/provisions"
+
+	"git.novox.be/novox/mesh-delivery/sdk/graph"
 )
 
 func fpOf(c byte) string { return delivery.SourcePrefix2 + strings.Repeat(string(c), 64) }
@@ -65,13 +68,16 @@ func TestEachRuleHoldsTheWantBack(t *testing.T) {
 		delivery.RuleCanary: func(_ *Module, n *Nodes) {
 			n.Haves["ace"]["mail"] = delivery.Have{FP: fOld, Phase: delivery.PhaseRunning, Health: delivery.HealthOK}
 		},
-		delivery.RuleProviders: func(_ *Module, n *Nodes) {
-			n.Haves["ace"]["store"] = delivery.Have{FP: fpOf('s'), Phase: delivery.PhaseRunning, Health: delivery.HealthWaits}
-		},
 		delivery.RuleGrant: func(m *Module, _ *Nodes) { m.Granted = false },
 		delivery.RuleComposed: func(m *Module, _ *Nodes) {
 			m.Composed = func(string, string) (delivery.ComposedDigest, bool) { return delivery.ComposedDigest{}, false }
 		},
+		// 1954/D1 (ADR 0570 §4): a provision of the module on that node still asked holds its want.
+		delivery.RuleProvisions: func(m *Module, _ *Nodes) {
+			m.Provisions = func(node string) map[string]provisions.Provision {
+				return map[string]provisions.Provision{node + ".mail.database": {Provision: "database", State: provisions.Asked}, node + ".mail.oidc": {Provision: "oidc", State: provisions.Provided}}
+			}
+		},
 	} {
 		m, n := ready()
 		breakIt(&m, &n)
@@ -85,6 +91,250 @@ func TestEachRuleHoldsTheWantBack(t *testing.T) {
 		if w := out.Wants["g14"]; w.FP != "" && (w.FP != fOld || w.Newest != fNew || w.Rule != rule) {
 			t.Errorf("rule %d broken: g14's want is %+v", rule, w)
 		}
+		if rule == delivery.RuleProvisions && (!strings.Contains(out.Rules["g14"].Words, "g14.mail.database") || !strings.Contains(out.Rules["g14"].Words, "asked")) {
+			t.Errorf("the provision's hold does not name its key and state: %s", out.Rules["g14"].Words)
+		}
+	}
+	// 1954/D1: every provision provided, the want moves; with the seat's state not read, nothing waits on it.
+	for _, all := range []func(string) map[string]provisions.Provision{
+		func(node string) map[string]provisions.Provision {
+			return map[string]provisions.Provision{node + ".mail.database": {Provision: "database", State: provisions.Provided}}
+		}, nil} {
+		m, n := ready()
+		m.Provisions = all
+		if out := Wants(m, n, wantedOld(), nil); out.Wants["g14"].FP != fNew {
+			t.Errorf("provided provisions held g14's want: %+v (%s)", out.Wants["g14"], out.Rules["g14"].Words)
+		}
+	}
+	// ADR 0614 §4: a want is held on a node whose engine does not state a reader capability the manifest needs, under rule 7
+	// with the capability as its words, and moves once the engine states it; an engine stating nothing reads the baseline,
+	// so a manifest of the baseline's words, the node-engine's own new build among them, is not held.
+	hostNeeds, err := catalogue.ManifestNeeds([]byte(`{"module":"mesh-host","version":"1","slug":"host","build":{"artifacts":[` +
+		`{"name":"host-arch","kind":"bundle","language":"go","system":"arch","from":"cmd/mesh-host"}]},"consumes":["restic.backed-up"],` +
+		`"state":[{"name":"health"}],"config":{"x":{"type":"number","minimum":1,"default":50,"runtime":true}},` +
+		`"resources":[{"id":"k","type":"file","path":"/var/lib/k","content":"${config:x}\n"}]}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, c := range []struct {
+		why   string
+		name  string
+		needs []string
+		reads map[string][]string
+		held  bool
+		// forms are the build's reference forms (ADR 0624 §2), and names what the hold's words name.
+		forms []string
+		names string
+	}{
+		{"a word the baseline lacks, on engines stating nothing", "mail", []string{"word:module", "word:tool-runner"}, nil, true, nil, "word:tool-runner"},
+		{"the same, once both engines state it", "mail", []string{"word:module", "word:tool-runner"},
+			map[string][]string{"ace": catalogue.ManifestReads(), "g14": catalogue.ManifestReads()}, false, nil, ""},
+		{"the baseline's words on engines stating nothing", "mail", []string{"word:claims.serves", "seat:mesh-catalog", "form:config"}, nil, false, nil, ""},
+		{"the node-engine's new build, whose contract has more words than its manifest uses", "mesh-host", hostNeeds, nil, false, nil, ""},
+		// ADR 0624 §2, with form:new a form no engine reads unless it states it and artifact-store the first form.
+		{"g14 back stating {old}, a build carrying {old,new}: moves", "mail", nil, map[string][]string{"g14": {"word:module"}}, false,
+			[]string{"form:artifact-store", "form:new"}, ""},
+		{"an engine stating nothing, a build carrying the baseline's form: moves", "mail", nil, nil, false, []string{"form:artifact-store"}, ""},
+		{"a build carrying {new} only: held, naming the form", "mail", nil, map[string][]string{"g14": {"word:module"}}, true,
+			[]string{"form:new"}, "form:new"},
+		{"the same, once g14's engine states it", "mail", nil, map[string][]string{"g14": {"form:new"}}, false, []string{"form:new"}, ""},
+		{"a manifest needing an unstated word, its build in the first form: held, naming the word", "mail", []string{"word:tool-runner"}, nil, true,
+			[]string{"form:artifact-store"}, "word:tool-runner"},
+	} {
+		m, n := ready()
+		m.Name, m.Needs, n.Reads, m.FormNeeds = c.name, c.needs, c.reads, c.forms
+		n.Haves["ace"][c.name], n.Haves["g14"][c.name] = n.Haves["ace"]["mail"], n.Haves["g14"]["mail"]
+		out := Wants(m, n, wantedOld(), nil)
+		if moved := out.Wants["g14"].FP == fNew; moved == c.held {
+			t.Errorf("%s: g14's want %+v, held by %+v", c.why, out.Wants["g14"], out.Rules["g14"])
+		}
+		if r := out.Rules["g14"]; c.held && (r.Rule != delivery.RuleComposed || !strings.Contains(r.Words, c.names) ||
+			!strings.Contains(r.Words, "node-engine of g14")) {
+			t.Errorf("%s: held by %+v, want rule 7 naming the capability", c.why, r)
+		}
+		if w := out.Wants["g14"]; c.held && (w.Rule != delivery.RuleComposed || w.Newest != fNew) {
+			t.Errorf("%s: g14's want %+v, want it kept at what it runs and naming rule 7", c.why, w)
+		}
+	}
+	// ADR 0614 §2, §3: a want waits, under the provisions' rule, until each verb it invokes is served by a running build,
+	// and moves once one is; a verb a running build serves already adds no wait, and an edge the graph leaves out on a cycle
+	// is not among Invokes, so it holds nothing; nothing read of what runs waits for none.
+	for _, c := range []struct {
+		name    string
+		invokes []string
+		served  []string
+		nilRead bool
+		holds   string
+	}{
+		{"a verb no running build serves", []string{"store.store_put", "seat:mesh-catalog.modules"}, []string{"store.store_put"}, false, "seat:mesh-catalog.modules"},
+		{"once a build serving it runs", []string{"seat:mesh-catalog.modules"}, []string{"seat:mesh-catalog.modules"}, false, ""},
+		{"an edge left out on a cycle", nil, nil, false, ""},
+		{"nothing read of what runs", []string{"seat:mesh-catalog.modules"}, nil, true, ""},
+		// ADR 0614 §5: a module asking bus state is held while no build offering bus-state runs, and moves once one does.
+		{"bus state no running build offers", nil, nil, false, graph.BusState},
+		{"bus state a running build offers", nil, []string{graph.BusState}, false, ""},
+		{"bus state its own module offers", nil, nil, false, ""},
+	} {
+		m, n := ready()
+		m.Invokes = c.invokes
+		if !c.nilRead {
+			m.Served = func(v string) bool { return slices.Contains(c.served, v) }
+		}
+		if strings.HasPrefix(c.name, "bus state") {
+			m.Manifest.BusState = []catalogue.BusStateEntry{{Name: "cache", Storage: "key-value"}}
+			m.Offering = func(p string) bool { return slices.Contains(c.served, p) }
+			if c.name == "bus state its own module offers" {
+				m.Manifest.Provides = []catalogue.Offer{{Name: graph.BusState, Scope: catalogue.ScopeMesh}}
+			}
+		}
+		words := graph.VerbWaitWords(c.holds, "mail", "g14")
+		if c.holds == graph.BusState {
+			words = graph.BusStateWaitWords("mail", "g14")
+		}
+		out := Wants(m, n, wantedOld(), nil)
+		if c.holds == "" {
+			if out.Wants["g14"].FP != fNew {
+				t.Errorf("%s: held %+v", c.name, out.Rules["g14"])
+			}
+			continue
+		}
+		if out.Wants["g14"].FP == fNew || out.Rules["g14"].Rule != delivery.RuleProvisions || out.Rules["g14"].Words != words {
+			t.Errorf("%s: want %+v, held by %+v", c.name, out.Wants["g14"], out.Rules["g14"])
+		}
+	}
+	// ADR 0603 §9: the newest source revision governs. The module now at fNew no longer requires the database an older revision
+	// asked for and requires oidc instead; the seat's keys follow the newest manifest, so the older edge is no wait: a provided
+	// oidc moves the want, an asked one holds it and names oidc and never database.
+	for _, c := range []struct {
+		name         string
+		state, older string
+		moves        bool
+	}{{"the replaced edge provided, the older edge retiring", provisions.Provided, provisions.Retiring, true},
+		{"the replaced edge provided, the older edge asked", provisions.Provided, provisions.Asked, true},
+		{"the replaced edge asked, the older edge retiring", provisions.Asked, provisions.Retiring, false}} {
+		m, n := ready()
+		m.Manifest.Requires = []string{"oidc"}
+		m.Provisions = func(node string) map[string]provisions.Provision {
+			return map[string]provisions.Provision{node + ".mail.oidc": {Provision: "oidc", State: c.state},
+				node + ".mail.database": {Provision: "database", State: c.older, Why: "the operator's answer"}}
+		}
+		out := Wants(m, n, wantedOld(), nil)
+		if got := out.Wants["g14"].FP == fNew; got != c.moves || (!c.moves && (!strings.Contains(out.Rules["g14"].Words, "oidc") || strings.Contains(out.Rules["g14"].Words, "database"))) {
+			t.Errorf("%s: want %+v, held by %q", c.name, out.Wants["g14"], out.Rules["g14"].Words)
+		}
+	}
+	// 1954/D1 (the lead, 2026-10-29): a required provision with no key yet holds the want, named; and only one the
+	// composition keys (catalogue.Awaited, issue 774), replaying 2026-10-30: grafana (not handed) waited on ace for
+	// oidc-client, which the controller still makes, and mesh-build-go (handed) for go-toolchain on its own machine.
+	{
+		handed := &catalogue.Handed{Source: "s", Digest: "d", Templates: map[string]string{"c": "c"}}
+		keycloak := catalogue.Manifest{Module: "keycloak", Provides: []catalogue.Offer{{Name: "oidc-client", Scope: catalogue.ScopeMesh}}}
+		proxy := catalogue.Manifest{Module: "route-proxy", Provides: []catalogue.Offer{{Name: "route", Scope: catalogue.ScopeMesh,
+			AnsweredBy: catalogue.AnsweredByHelper}}}
+		store := catalogue.Manifest{Module: "store", Provides: []catalogue.Offer{{Name: "database", Scope: catalogue.ScopeMesh}}}
+		goTools := catalogue.Manifest{Module: "go", Provides: []catalogue.Offer{{Name: "go-toolchain", Scope: catalogue.ScopeNode}}}
+		gitea := catalogue.Manifest{Module: "gitea", Provides: []catalogue.Offer{{Name: "forge-account", Scope: catalogue.ScopeMesh}}}
+		answering := func(p string) []catalogue.Manifest {
+			for _, m := range []catalogue.Manifest{keycloak, proxy, store, goTools, gitea} {
+				if m.Provides[0].Name == p {
+					return []catalogue.Manifest{m}
+				}
+			}
+			return nil
+		}
+		for _, c := range []struct {
+			name     string
+			manifest catalogue.Manifest
+			missing  string // the provision named, "" for none: the want moves
+		}{
+			{"a handed module's database with no key", catalogue.Manifest{Module: "mail", Moved: true, Handed: handed,
+				Requires: []string{"database"}}, "database"},
+			{"a module not handed waits for no login the controller makes (grafana on ace, oidc-client)",
+				catalogue.Manifest{Module: "mail", Requires: []string{"oidc-client"}}, ""},
+			{"a module not handed waits for its route, which the helper answers (grafana's route)",
+				catalogue.Manifest{Module: "mail", Requires: []string{"oidc-client", "route"}}, "route"},
+			{"a handed builder waits for no toolchain on its own machine (mesh-build-go, go-toolchain)",
+				catalogue.Manifest{Module: "mail", Moved: true, Handed: handed, Requires: []string{"go-toolchain"}}, ""},
+			{"and does wait for its forge account", catalogue.Manifest{Module: "mail", Moved: true, Handed: handed,
+				Requires: []string{"go-toolchain", "forge-account"}}, "forge-account"},
+		} {
+			m, n := ready()
+			m.Manifest, m.Answering = c.manifest, answering
+			m.Provisions = func(string) map[string]provisions.Provision { return map[string]provisions.Provision{} }
+			out := Wants(m, n, wantedOld(), nil)
+			if c.missing == "" {
+				if out.Wants["g14"].FP != fNew || len(m.MissingProvisions("g14")) != 0 {
+					t.Errorf("%s: held %+v", c.name, out.Rules["g14"])
+				}
+				continue
+			}
+			if out.Rules["g14"].Rule != delivery.RuleProvisions || !strings.Contains(out.Rules["g14"].Words,
+				"provision "+c.missing+" has no key yet") || len(m.MissingProvisions("g14")) != 1 {
+				t.Errorf("%s: %+v", c.name, out.Rules["g14"])
+			}
+		}
+	}
+	// ADR 0603 §5: a requirement nobody offers is an unknown provider and waits, loudly; one something offers (a module's own
+	// name, a module the mesh provides itself) is left to catalogue.Awaited as before and does not.
+	for _, c := range []struct {
+		name, requires string
+		offered        bool
+	}{{"a module's own name (node-tools)", "node-tools", true}, {"a module the mesh provides itself (mesh-addressing)", "mesh-addressing", true},
+		{"a provision nobody offers", "database", false}} {
+		m, n := ready()
+		m.Manifest.Requires = []string{c.requires}
+		m.Answering = func(string) []catalogue.Manifest { return nil }
+		m.Offered = func(p string) bool { return c.offered && p == c.requires }
+		m.Provisions = func(string) map[string]provisions.Provision { return map[string]provisions.Provision{} }
+		out := Wants(m, n, wantedOld(), nil)
+		if got := out.Wants["g14"].FP == fNew; got != c.offered || (!c.offered && (out.Rules["g14"].Rule != delivery.RuleProvisions ||
+			!strings.Contains(out.Rules["g14"].Words, "no module offers database yet") || !strings.Contains(out.Rules["g14"].Words, "past its bound"))) {
+			t.Errorf("%s: want %+v, held by %+v", c.name, out.Wants["g14"], out.Rules["g14"])
+		}
+	}
+	// 1960: rule 5 holds no want, and no module is left without a first want for a provider down or a node offline; the
+	// provider down is said (Unreached). novox on 2026-10-29: route-proxy down held de-spiegel and link2pay, minio not
+	// healthy held photos, and novox offline left a module with no canary.
+	for _, c := range []struct {
+		name, module, provision, provider string
+		have                              *delivery.Have // what novox runs of the module; nil: a new assignment
+		before                            map[string]delivery.Want
+		online                            bool
+		want                              string
+	}{
+		{"de-spiegel, route-proxy down, old form", "de-spiegel", "route", "route-proxy",
+			&delivery.Have{FP: "build-1", Phase: delivery.PhaseRunning, Health: delivery.HealthUnknown}, nil, true, fNew},
+		{"link2pay, route-proxy down, new assignment", "link2pay", "route", "route-proxy", nil, nil, true, fNew},
+		{"photos, minio not healthy, moving its want", "photos", "s3-bucket", "minio",
+			&delivery.Have{FP: fOld, Phase: delivery.PhaseRunning, Health: delivery.HealthOK},
+			map[string]delivery.Want{"novox": {FP: fOld, Composed: dig(fOld)}}, true, fNew},
+		{"novox offline, no canary, new assignment", "link2pay", "route", "route-proxy", nil, nil, false, fNew},
+		{"novox offline, no canary, moving its want", "photos", "s3-bucket", "minio",
+			&delivery.Have{FP: fOld, Phase: delivery.PhaseRunning, Health: delivery.HealthOK},
+			map[string]delivery.Want{"novox": {FP: fOld, Composed: dig(fOld)}}, false, fOld},
+	} {
+		m := Module{Name: c.module, FP: fNew, Built: true, Granted: true, Composed: composedEverywhere, Nodes: []string{"novox"},
+			Manifest: catalogue.Manifest{Module: c.module, Requires: []string{c.provision}}}
+		n := Nodes{Online: map[string]bool{"novox": c.online}, Haves: map[string]map[string]delivery.Have{"novox": {
+			c.provider: {FP: fpOf('p'), Phase: delivery.PhaseFailed, Health: delivery.HealthFailed}}},
+			Providers: map[string]map[string][]string{c.provision: {c.provider: {"novox"}}}}
+		if c.have != nil {
+			n.Haves["novox"][c.module] = *c.have
+		}
+		out := Wants(m, n, c.before, nil)
+		w, written := out.Wants["novox"]
+		if !written {
+			w = c.before["novox"]
+		}
+		if w.FP != c.want || w.Removed {
+			t.Errorf("%s: novox's want = %+v, want %s", c.name, w, short(c.want))
+		}
+		if _, on := out.Neither["novox"]; on {
+			t.Errorf("%s: on neither list: %+v", c.name, out.Neither)
+		}
+		if c.online && !strings.Contains(out.Unreached["novox"], c.provision) {
+			t.Errorf("%s: the provider down is not said: %q", c.name, out.Unreached["novox"])
+		}
 	}
 
 	// 1126/AC-SW1, AC-SW2, AC-SW3: a want written Self while g14 was placed, kept by a rule after the placement is gone, names
@@ -108,7 +358,7 @@ func TestEachRuleHoldsTheWantBack(t *testing.T) {
 		{name: "rule 5 at F", before: fNew, set: func(m *Module, n *Nodes) {
 			atF(m, n)
 			n.Haves["ace"]["store"] = delivery.Have{FP: fpOf('s'), Phase: delivery.PhaseRunning, Health: delivery.HealthWaits}
-		}, want: delivery.Want{FP: fNew, Composed: dig(fNew)}, rule: delivery.RuleProviders},
+		}, want: delivery.Want{FP: fNew, Composed: dig(fNew)}},
 		{name: "rule 3 at F", before: fNew, set: func(m *Module, n *Nodes) {
 			atF(m, n)
 			n.Haves["ace"]["mail"] = delivery.Have{FP: fOld, Phase: delivery.PhaseRunning, Health: delivery.HealthOK}
@@ -180,7 +430,7 @@ func TestEachRuleHoldsTheWantBack(t *testing.T) {
 	// Rule 6 per node: a grant written for the module's other nodes does not grant a node whose account it does not name
 	// (issue 1945, live on 2026-10-25 at 20:04: ace's mesh-build-go was wanted with no account on the bus).
 	m, n := ready()
-	grant := delivery.ControllerGrant{Accounts: []string{"ace.mail", "ace.mail.send"}}
+	grant := delivery.Grant{Accounts: []string{"ace.mail", "ace.mail.send"}}
 	m.GrantedOn = func(node string) bool { return GrantNamesNode(grant, node, "mail") }
 	out := Wants(m, n, wantedOld(), nil)
 	if w := out.Wants["ace"]; w.FP != fNew {
@@ -199,7 +449,7 @@ func TestEachRuleHoldsTheWantBack(t *testing.T) {
 		{[]string{"g14.mailer"}, "g14", "mail", false},
 		{[]string{"ace.mail"}, "g14", "mail", false},
 	} {
-		if got := GrantNamesNode(delivery.ControllerGrant{Accounts: c.accounts}, c.node, c.module); got != c.named {
+		if got := GrantNamesNode(delivery.Grant{Accounts: c.accounts}, c.node, c.module); got != c.named {
 			t.Errorf("%v names %s of %s: %v, want %v", c.accounts, c.module, c.node, got, c.named)
 		}
 	}
@@ -526,11 +776,13 @@ func TestAMoveJudgedNeitherOrNeverRunOrNotRecordedIsWrittenAtOnce(t *testing.T)
 
 // 1906/D4 (ADR 0539 §7, §15): the bus module's new fingerprint is never written by the assigner, but a revision of its
 // composition at the same fingerprint that only changes the user list (judged neither) is written at once.
-func TestTheBusIsNotMovedButItsUserListRevisionIsWrittenAtOnce(t *testing.T) {
+func TestTheBusMovesByTheRulesAndItsUserListRevisionIsWrittenAtOnce(t *testing.T) {
 	m, n, _ := movingTo(delivery.JudgedNeither)
 	m.Manifest.Provides = []catalogue.Offer{{Name: "mesh-bus"}}
-	if out := Wants(m, n, wantedOld(), nil); out.Wants["ace"].FP == fNew {
-		t.Errorf("the bus moved to a new fingerprint: %+v", out.Wants["ace"])
+	// ADR 0601 §1, §2: the bus module's want is written by the rules, as any module's, and no snapshot is asked for it: its node
+	// backs its streams up before it applies.
+	if out := Wants(m, n, wantedOld(), nil); out.Wants["ace"].FP != fNew || len(out.Record) != 0 || len(out.Neither) != 0 {
+		t.Errorf("the bus did not move by the rules: %+v", out)
 	}
 	running := map[string]delivery.Want{"ace": {FP: fNew, Composed: dig(fOld)}, "g14": {FP: fNew, Composed: dig(fOld)}}
 	out := Wants(m, n, running, nil)
@@ -583,23 +835,6 @@ func TestTheBusIsNotMovedButItsUserListRevisionIsWrittenAtOnce(t *testing.T) {
 		t.Errorf("a held bus did not take its user-list revision as a put: %+v", w)
 	}
 	m.Puts = nil
-	// 1945 (the bus bar made loud): a node that runs the bus at an old-form build and holds no want for it gets none, since only
-	// the operator's put moves the bus, and the pass says so: a holding naming the bar, and the node on neither list so its
-	// condition stays raised. A node with a live want keeps it and is not on neither list.
-	m.Composed = composedEverywhere
-	n.Haves["ace"]["mail"] = delivery.Have{FP: "b-1700000000-oldform", Phase: delivery.PhaseRunning, Health: delivery.HealthOK}
-	out = Wants(m, n, map[string]delivery.Want{"g14": {FP: fOld, Composed: dig(fOld)}}, nil)
-	if w, wrote := out.Wants["ace"]; wrote {
-		t.Errorf("the bus bar wrote ace's want %+v", w)
-	}
-	h, on := out.Neither["ace"]
-	if !on || !h.Bus || out.Rules["ace"] != h || !strings.Contains(h.Words, "only your put moves the bus") || !strings.Contains(h.Words, "ace runs b-1700000000-oldform") ||
-		!strings.Contains(h.Words, "assigner_put") {
-		t.Errorf("the barred bus on ace: neither %+v (%v), rules %+v", h, on, out.Rules["ace"])
-	}
-	if _, on := out.Neither["g14"]; on || out.Wants["g14"].FP == fNew {
-		t.Errorf("g14 has a live want: neither %+v, its want %+v", out.Neither, out.Wants["g14"])
-	}
 	stepsOfAPut(t)
 }
 
@@ -702,6 +937,13 @@ func TestTheBackupAnswerStaysInTheWantWhileItsTargetStays(t *testing.T) {
 	if w, ok := Wants(m, n, running, nil).Wants["ace"]; ok {
 		t.Errorf("the answer was erased: %+v", w)
 	}
+	// A placed node composes its own: its want names the build alone, and the answer stays in it all the same (the digest its
+	// have names is not in the want, so a want kept for its digest would erase the answer at every pass).
+	m.Self = func(string) bool { return true }
+	placed := map[string]delivery.Want{"ace": {FP: fNew, Self: true, Backup: delivery.BackupSkip, Words: BackupAnswerWords("skip", 0)}}
+	if w, ok := Wants(m, n, placed, nil).Wants["ace"]; ok {
+		t.Errorf("the answer in a placed node's want was erased: %+v", w)
+	}
 }
 
 // 1906/D4 (ADR 0539 §19): a hold released by the operator is not held again by a health check that failed before, and the
@@ -761,10 +1003,16 @@ func TestTheRecordPolicyIsTheOneTheControllerHolds(t *testing.T) {
 	if out := Wants(m, n, wanted, nil); len(out.Record) == 0 {
 		t.Errorf("a hand-made composition fell through the manifest's record policy: %+v", out)
 	}
+	// 1953/D4 (ADR 0565 §7): a person's choice at the assigner is over the controller's beside the composition.
+	with(delivery.PolicyRecord, "person")
+	m.Chosen = &catalogue.PersonPolicy{V: catalogue.PersonPolicyVersion, Module: m.Name, Policy: catalogue.PolicyRoll, Why: "w", By: "op"}
+	if out := Wants(m, n, wanted, nil); len(out.Record) != 0 || out.Wants["ace"].FP != fNew {
+		t.Errorf("a person's roll at the assigner was not honoured over the controller's record: %+v", out)
+	}
 }
 
-// Review round 1, item 2 (ADR 0539 §15): a node that runs the bus with no readable want compares the new fingerprint with the one
-// it runs, from its have: the same fingerprint is not a new one (written by the rules), another is barred.
+// A node that runs the bus with no readable want gets its want by the rules, at the fingerprint it runs or at a new one alike: the
+// bus has no bar of its own (ADR 0601 §1).
 func TestTheBusWithNoWantIsComparedWithWhatItRuns(t *testing.T) {
 	m, n, _ := movingTo(delivery.JudgedNeither)
 	m.Manifest.Provides = []catalogue.Offer{{Name: "mesh-bus"}}
@@ -773,8 +1021,8 @@ func TestTheBusWithNoWantIsComparedWithWhatItRuns(t *testing.T) {
 		t.Errorf("the bus runs F with no want and was not given one: %+v %v", w, ok)
 	}
 	n.Haves["ace"]["mail"] = delivery.Have{FP: fOld, Phase: delivery.PhaseRunning, Health: delivery.HealthOK}
-	if w, ok := Wants(m, n, nil, nil).Wants["ace"]; ok {
-		t.Errorf("the bus was moved to a new fingerprint with no want: %+v", w)
+	if w, ok := Wants(m, n, nil, nil).Wants["ace"]; !ok || w.FP != fNew {
+		t.Errorf("the bus running an older fingerprint with no want was not given its want by the rules: %+v %v", w, ok)
 	}
 }
 
@@ -962,10 +1210,12 @@ func x11() (Module, Nodes) {
 func TestANodeRunningAModuleWithNoWantGetsItsFirstWantAtWhatItRuns(t *testing.T) {
 	m, n := x11()
 	out := Wants(m, n, nil, nil)
-	for _, node := range []string{"g14", "shanks"} {
-		if w := out.Wants[node]; w.FP != fOld || w.Composed != dig(fOld) || w.Newest != fNew || w.Rule == 0 {
-			t.Errorf("%s's want = %+v, want its first want at the fingerprint it runs, held back from F", node, w)
-		}
+	// 1960: the providers rule holds no want: the canary g14 gets F, its provider's health unknown said
+	if w := out.Wants["g14"]; w.FP != fNew || out.Unreached["g14"] == "" {
+		t.Errorf("g14's want = %+v (unreached %q), want F, the provider said", w, out.Unreached["g14"])
+	}
+	if w := out.Wants["shanks"]; w.FP != fOld || w.Composed != dig(fOld) || w.Newest != fNew || w.Rule != delivery.RuleCanary {
+		t.Errorf("shanks's want = %+v, want its first want at the fingerprint it runs, held back from F by the canary", w)
 	}
 	if len(out.Neither) != 0 {
 		t.Errorf("left on neither list: %+v", out.Neither)
@@ -1003,11 +1253,22 @@ func TestNoFirstWantWithoutTheCompositionAndGrantOfWhatItRuns(t *testing.T) {
 		m, n := x11()
 		change(&m, &n)
 		out := Wants(m, n, nil, nil)
-		if w, ok := out.Wants["shanks"]; ok {
-			t.Errorf("%s: shanks got a want: %+v", what, w)
+		if what == "an old-form build" {
+			// the canary g14 does not run F healthy: no want, on neither list by rule 3 (issue 1945)
+			if w, ok := out.Wants["shanks"]; ok {
+				t.Errorf("%s: shanks got a want: %+v", what, w)
+			}
+			if h, ok := out.Neither["shanks"]; !ok || h.Rule != delivery.RuleCanary {
+				t.Errorf("%s: shanks on neither list = %+v (named %v), want rule 3", what, h, ok)
+			}
+			continue
 		}
-		if h, ok := out.Neither["shanks"]; !ok || h.Rule == 0 {
-			t.Errorf("%s: shanks on neither list = %+v (named %v)", what, h, ok)
+		// 1960: no want can name what it runs, so its first want names F rather than none: never on neither list
+		if w := out.Wants["shanks"]; w.FP != fNew {
+			t.Errorf("%s: shanks's want = %+v, want F", what, w)
+		}
+		if h, ok := out.Neither["shanks"]; ok {
+			t.Errorf("%s: shanks on neither list = %+v", what, h)
 		}
 	}
 	m, n := x11()
@@ -1016,10 +1277,12 @@ func TestNoFirstWantWithoutTheCompositionAndGrantOfWhatItRuns(t *testing.T) {
 	if len(out.Neither) != 0 {
 		t.Errorf("nodes holding a want named on neither list: %+v", out.Neither)
 	}
-	for node, w := range out.Wants {
-		if w.FP != fOld {
-			t.Errorf("%s's want moved from its want past the ordering rules: %+v", node, w)
-		}
+	// the canary g14 moves to F (its provider's health no rule); shanks waits for it
+	if w := out.Wants["shanks"]; w.FP != "" && w.FP != fOld {
+		t.Errorf("shanks's want moved from its want past the canary: %+v", w)
+	}
+	if w := out.Wants["g14"]; w.FP != fNew {
+		t.Errorf("the canary g14's want = %+v, want F", w)
 	}
 }
 
@@ -1030,11 +1293,12 @@ func TestANewAssignmentWaitingIsNotOnNeitherList(t *testing.T) {
 	m, n := x11()
 	delete(n.Haves["shanks"], "screen-lock")
 	out := Wants(m, n, nil, nil)
-	if w, ok := out.Wants["shanks"]; ok {
-		t.Errorf("a new assignment waiting for the canary got a want: %+v", w)
+	// 1960: the canary orders moves, never a first want: the new assignment is wanted at F
+	if w := out.Wants["shanks"]; w.FP != fNew {
+		t.Errorf("a new assignment while the canary does not run F: %+v, want F", w)
 	}
 	if _, ok := out.Neither["shanks"]; ok {
-		t.Errorf("a new assignment waiting for the canary is named on neither list: %+v", out.Neither)
+		t.Errorf("a new assignment is named on neither list: %+v", out.Neither)
 	}
 	m.Built = false
 	if out := Wants(m, n, nil, nil); len(out.Neither) != 1 || out.Neither["g14"].Rule != delivery.RuleBuildDone {
@@ -1076,7 +1340,7 @@ func TestANewAssignmentWaitingIsNotOnNeitherList(t *testing.T) {
 // 1945/AC21: a node whose have names an old-form build (no fingerprint of the new form, so no composition of it) can never be
 // named in a want at what it runs; its first want names F, under the canary rule as usual and with everything F needs and the
 // providers rule. Given the canary runs F healthy, shanks's first want names F; given it does not yet, shanks gets no want and
-// stays on neither list. The old-form node that is itself the canary gets F once its providers run healthy.
+// stays on neither list; the providers hold no want (issue 1960). The old-form node that is itself the canary gets F once its providers run healthy.
 func TestAnOldFormNodeGetsItsFirstWantAtFOnlyUnderTheCanary(t *testing.T) {
 	oldForm := func(n Nodes, node string) {
 		n.Haves[node]["screen-lock"] = delivery.Have{FP: "build-1792260876956849831", Phase: delivery.PhaseRunning, Health: delivery.HealthUnknown}
@@ -1110,16 +1374,16 @@ func TestAnOldFormNodeGetsItsFirstWantAtFOnlyUnderTheCanary(t *testing.T) {
 	if h, ok := out.Neither["shanks"]; !ok || h.Rule != delivery.RuleCanary {
 		t.Errorf("canary not healthy on F: shanks on neither list = %+v (named %v), want rule 3", h, ok)
 	}
-	// the canary healthy on F but the providers not healthy on shanks: rule 5 still holds it back
+	// 1960: the canary healthy on F but the providers not healthy on shanks: F all the same, the provider down said
 	m, n = x11()
 	oldForm(n, "shanks")
 	n.Haves["g14"]["screen-lock"] = delivery.Have{FP: fNew, Phase: delivery.PhaseRunning, Health: delivery.HealthOK}
 	out = Wants(m, n, nil, nil)
-	if w, ok := out.Wants["shanks"]; ok {
-		t.Errorf("providers not healthy: shanks got a want: %+v", w)
+	if w := out.Wants["shanks"]; w.FP != fNew || out.Unreached["shanks"] == "" {
+		t.Errorf("providers not healthy: shanks's want = %+v (unreached %q), want F, the provider said", w, out.Unreached["shanks"])
 	}
-	if h := out.Neither["shanks"]; h.Rule != delivery.RuleProviders {
-		t.Errorf("providers not healthy: shanks on neither list = %+v, want rule 5", h)
+	if _, on := out.Neither["shanks"]; on {
+		t.Errorf("providers not healthy: shanks on neither list: %+v", out.Neither)
 	}
 	// F not granted: nothing, even with the canary healthy
 	m, n = x11()

modules/mesh-delivery-assigner/internal/judge/judge.go

@@ -0,0 +1,332 @@
+// Package judge is how the seat mesh-placement's holder judges a proposal (novox/hq ADR 0567 §3, §4, as ADR 0593 §8
+// changes them): what it changes on each node by its placement (Intended), every node answering it, and the verdict of
+// their answers (JudgeAnswers). The assigner's own (ADR 0593 §1), moved back from mesh-sdk's compose/judge: the holder
+// composes nothing, since every composition is its node's engine's, and a node answers through the candidates path
+// with what it composed. It holds no bus client and no timer: the holder gives it what it read.
+package judge
+
+import (
+	"encoding/json"
+	"fmt"
+	"reflect"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+
+	nec "git.novox.be/novox/mesh-contracts/go/clients/nodeengineclient"
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// AnswerBound is how long the holder waits for a node's answer after its candidate was written: the time to live of the
+// node's pulse key (delivery.PulseAnswerKey), whose expiry names it as giving no answer, never passed. The same answer
+// bound a check gives a node (ADR 0593 §8, §7: 60 seconds, nec.AnswerBound). A variable so a test on the bus
+// can shorten it.
+var AnswerBound = nec.AnswerBound
+
+// Intended is, by node, the modules whose placed entry the proposal changes there, and the nodes that answer it: every
+// node (ADR 0593 §8, changing ADR 0567 §4's list of the nodes that must answer), sorted. current is the placement as it
+// stands, laid the proposal's placements by node (nil removes the node's key) and nodes every node with a record. A
+// node's set holds the modules the proposal adds, removes or whose placed entry differs on that node; a node with no
+// key now gets an empty set (§7: the seed is answered as the same). What a node's compositions change beyond its own
+// placement it says itself in its answer, marked in the brief as not computed.
+func Intended(current map[string]delivery.Placement, laid map[string]*delivery.Placement, nodes []string) (intended map[string]map[string]bool, must []string) {
+	intended = map[string]map[string]bool{}
+	all := map[string]bool{}
+	for _, n := range nodes {
+		all[n] = true
+	}
+	for n := range laid {
+		all[n] = true
+	}
+	for node := range all {
+		must = append(must, node)
+		set := map[string]bool{}
+		intended[node] = set
+		before, placed := current[node]
+		after, changesKey := laid[node]
+		if !changesKey || !placed {
+			continue // untouched, or new to placement: every answer must be the same
+		}
+		var afterModules []delivery.PlacedModule
+		if after != nil {
+			afterModules = after.Modules
+		}
+		entries := map[string]delivery.PlacedModule{}
+		for _, m := range before.Modules {
+			entries[m.Module] = m
+		}
+		seen := map[string]bool{}
+		for _, m := range afterModules {
+			seen[m.Module] = true
+			if e, ok := entries[m.Module]; !ok || !reflect.DeepEqual(e, m) {
+				set[m.Module] = true
+			}
+		}
+		for name := range entries {
+			if !seen[name] {
+				set[name] = true
+			}
+		}
+	}
+	sort.Strings(must)
+	return intended, must
+}
+
+// JudgeAnswers is the verdict of a proposal's answers (§4). answers is by node its HaveNode.Candidates entry for the
+// proposal (nil when it has none) and revisions by node the revision of its candidate key: an answer counts when it
+// names the proposal and that revision. It fails on a refusal by a node that must answer; a node of Must with no answer
+// that counts is waited for while its pulse key stands, and once it has ended (pulsing false: the bound's expiry, heard
+// on the bus) is named as giving no answer and the proposal decided on the answers it has (ADR 0593 §8).
+// A difference fails nothing: one Intended computed is listed under Intended, one it did not under Unintended, both
+// shown in the ask's brief. The seed alone fails on any difference.
+func JudgeAnswers(p delivery.PlacementProposal, intended map[string]map[string]bool, answers map[string]*delivery.CandidateAnswer,
+	revisions map[string]uint64, online map[string]bool, pulsing map[string]bool, now time.Time) delivery.PlacementVerdict {
+	v := delivery.PlacementVerdict{At: now.UTC(), Intended: map[string][]string{}, Unintended: map[string][]string{}, Carried: map[string][]string{},
+		Answers: map[string]delivery.CandidateAnswer{}}
+	for node, set := range intended {
+		for m := range set {
+			v.Intended[node] = append(v.Intended[node], m)
+		}
+		sort.Strings(v.Intended[node])
+	}
+	must := p.Must
+	if len(must) == 0 {
+		must = p.Nodes()
+	}
+	for _, node := range must {
+		a := answers[node]
+		if a == nil || a.Proposal != p.ID || a.Revision == 0 || a.Revision != revisions[node] {
+			v.Silent = append(v.Silent, node)
+			continue
+		}
+		v.Answers[node] = *a
+		if a.Refused != "" {
+			v.Fails = append(v.Fails, fmt.Sprintf("%s cannot compose the proposal: %s", node, a.Refused))
+			continue
+		}
+		for _, r := range a.Refusals {
+			v.Fails = append(v.Fails, fmt.Sprintf("%s refuses the proposal for %s: %s", node, r.Module, r.Why))
+		}
+		want := intended[node]
+		differs := func(module, words string) {
+			if p.Seed {
+				// The seed carries what its nodes found, each named in the brief for the operator who approves it.
+				v.Carried[node] = append(v.Carried[node], words)
+				return
+			}
+			if !want[module] {
+				v.Unintended[node] = append(v.Unintended[node], module)
+			}
+		}
+		for _, d := range a.Differs {
+			differs(d.Module, differenceWords(d))
+		}
+		for _, d := range a.Added {
+			differs(d.Module, "would run "+d.Module)
+		}
+		for _, m := range a.Removed {
+			differs(m, "would stop running "+m)
+		}
+		sort.Strings(v.Unintended[node])
+	}
+	if len(v.Intended) == 0 {
+		v.Intended = nil
+	}
+	if len(v.Unintended) == 0 {
+		v.Unintended = nil
+	}
+	if len(v.Carried) == 0 {
+		v.Carried = nil
+	}
+	if len(v.Answers) == 0 {
+		v.Answers = nil
+	}
+	var waiting, gone []string
+	for _, node := range v.Silent {
+		named := node
+		if online != nil && !online[node] {
+			named += " (offline)"
+		}
+		if pulsing[node] {
+			waiting = append(waiting, named)
+		} else {
+			gone = append(gone, named)
+		}
+	}
+	if len(waiting) > 0 {
+		v.Notes = append(v.Notes, fmt.Sprintf("waits for the answers of %s, each for %s from its candidate's write",
+			strings.Join(waiting, ", "), AnswerBound))
+	}
+	if len(gone) > 0 {
+		// ADR 0593 §8: decided on the answers it has; that node's own composition judges again when it applies (§9).
+		v.Notes = append(v.Notes, fmt.Sprintf("no answer from %s within %s of its candidate's write: decided on the answers "+
+			"it has, and that node's own composition judges again when it applies", strings.Join(gone, ", "), AnswerBound))
+	}
+	switch {
+	case len(v.Fails) > 0:
+		v.State = delivery.VerdictFail
+	case len(waiting) > 0:
+		v.State = delivery.VerdictWaits
+	default:
+		v.State = delivery.VerdictPass
+	}
+	return v
+}
+
+// Brief is the verdict as the ask's brief shows it, by node (§5): what the proposal changes and what each node answered
+// beside it, marked, and what stays held as the node holds it today, with the proposal's why.
+func Brief(p delivery.PlacementProposal, v delivery.PlacementVerdict) string {
+	var b strings.Builder
+	fmt.Fprintf(&b, "%s (proposed by %s)", p.Why, p.By)
+	nodes := map[string]bool{}
+	for n := range v.Intended {
+		nodes[n] = true
+	}
+	for n := range v.Unintended {
+		nodes[n] = true
+	}
+	for _, n := range p.Nodes() {
+		nodes[n] = true
+	}
+	for n, a := range v.Answers {
+		if len(a.Held) > 0 {
+			nodes[n] = true
+		}
+	}
+	for n := range v.Carried {
+		nodes[n] = true
+	}
+	names := make([]string, 0, len(nodes))
+	for n := range nodes {
+		names = append(names, n)
+	}
+	sort.Strings(names)
+	for _, n := range names {
+		fmt.Fprintf(&b, "; %s:", n)
+		if m := v.Intended[n]; len(m) > 0 {
+			fmt.Fprintf(&b, " changes %s", strings.Join(m, ", "))
+		} else {
+			b.WriteString(" composes the same")
+		}
+		if m := v.Unintended[n]; len(m) > 0 {
+			fmt.Fprintf(&b, "; also differs, not computed: %s", strings.Join(m, ", "))
+		}
+		if m := v.Carried[n]; len(m) > 0 {
+			fmt.Fprintf(&b, "; the seed carries: %s", strings.Join(m, "; "))
+		}
+		if held := v.Answers[n].Held; len(held) > 0 {
+			var names []string
+			for _, h := range held {
+				today := h.Today
+				if today == "" {
+					today = "held"
+				}
+				names = append(names, h.Module+" ("+today+")")
+			}
+			fmt.Fprintf(&b, "; stays as today: %s", strings.Join(names, ", "))
+		}
+	}
+	return b.String()
+}
+
+// differenceWords names one module's difference: the module, the first field that differs in it with its value as it
+// runs and as the seed composes it, each cut to about 60 characters ("(value cut)" where a body shown is cut before the
+// field), and how many fields more; or the resource and why when no body is shown.
+func differenceWords(d delivery.ModuleDiffers) string {
+	for _, b := range d.Bodies {
+		if len(b.Paths) == 0 {
+			continue
+		}
+		path := b.Paths[0]
+		words := fmt.Sprintf("%s: %s %s → %s", d.Module, fieldName(b.Running, b.Composed, path),
+			valueAt(b.Running, path), valueAt(b.Composed, path))
+		if n := len(b.Paths) - 1; n > 0 {
+			words += fmt.Sprintf(" (and %d more fields)", n)
+		}
+		return words
+	}
+	if d.Resource != "" {
+		return fmt.Sprintf("%s: %s (%s)", d.Module, d.Resource, d.Why)
+	}
+	return fmt.Sprintf("%s: %s", d.Module, d.Why)
+}
+
+// shownValue bounds a value named in a brief.
+const shownValue = 60
+
+// walk follows a differing path (delivery.DifferingPaths: keys joined by dots, a key may hold dots, and a JSON value
+// written in a string is read as JSON) through a body, answering the keys it passed and the value at its end.
+func walk(body, path string) (keys []string, value any, ok bool) {
+	var v any
+	if json.Unmarshal([]byte(body), &v) != nil {
+		return nil, nil, false
+	}
+	rest := path
+	for rest != "" {
+		if s, isString := v.(string); isString {
+			var inner any
+			if json.Unmarshal([]byte(s), &inner) != nil {
+				return nil, nil, false
+			}
+			v = inner
+		}
+		switch t := v.(type) {
+		case map[string]any:
+			best := ""
+			for k := range t {
+				if (rest == k || strings.HasPrefix(rest, k+".")) && len(k) > len(best) {
+					best = k
+				}
+			}
+			if best == "" {
+				return nil, nil, false
+			}
+			keys, v, rest = append(keys, best), t[best], strings.TrimPrefix(strings.TrimPrefix(rest, best), ".")
+		case []any:
+			seg, after, _ := strings.Cut(rest, ".")
+			n, err := strconv.Atoi(seg)
+			if err != nil || n < 0 || n >= len(t) {
+				return nil, nil, false
+			}
+			keys, v, rest = append(keys, seg), t[n], after
+		default:
+			return nil, nil, false
+		}
+	}
+	return keys, v, true
+}
+
+// valueAt is the value at path in a shown body, cut to shownValue, or why it is not shown.
+func valueAt(body, path string) string {
+	if body == "" {
+		return "(none)"
+	}
+	_, v, ok := walk(body, path)
+	if !ok {
+		return "(value cut)"
+	}
+	s, isString := v.(string)
+	if !isString {
+		raw, _ := json.Marshal(v)
+		s = string(raw)
+	}
+	if r := []rune(s); len(r) > shownValue {
+		s = string(r[:shownValue-1]) + "…"
+	}
+	return s
+}
+
+// fieldName is the differing field as a person reads it: its parent's name and its own, `PARENT[key]`, from whichever
+// body reaches it; the path's end when neither does.
+func fieldName(running, composed, path string) string {
+	for _, body := range []string{running, composed} {
+		if keys, _, ok := walk(body, path); ok && len(keys) > 0 {
+			if len(keys) == 1 {
+				return keys[0]
+			}
+			return keys[len(keys)-2] + "[" + keys[len(keys)-1] + "]"
+		}
+	}
+	return path
+}

modules/mesh-delivery-assigner/internal/judge/judge_test.go

@@ -0,0 +1,91 @@
+package judge
+
+import (
+	"slices"
+	"strings"
+	"testing"
+	"time"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// ADR 0567 §3, §4 (rows moved from the assigner's check of a pull request's placement, ADR 0559 §5): what a proposal
+// changes by node, and the verdict of the answers: differences shown and failing nothing, a refusal and a silent node
+// failing, a later answer judging again, the seed failing on any difference.
+func TestJudge(t *testing.T) {
+	current := map[string]delivery.Placement{"anchor": {Node: "anchor", Modules: []delivery.PlacedModule{{Module: "mail"}}}, "server": {Node: "server"}}
+	laid := map[string]*delivery.Placement{
+		"anchor": {Node: "anchor", Modules: []delivery.PlacedModule{{Module: "mail", Ports: map[string]int{"25": 2525}}, {Module: "web"}}},
+		"laptop": {Node: "laptop", Modules: []delivery.PlacedModule{{Module: "web"}}}}
+	// ADR 0593 §8: every node answers; what the placement changes is read from the placement alone.
+	got, must := Intended(current, laid, []string{"anchor", "laptop", "server"})
+	if !got["anchor"]["mail"] || !got["anchor"]["web"] || len(got["laptop"]) != 0 || len(got["server"]) != 0 ||
+		!slices.Equal(must, []string{"anchor", "laptop", "server"}) {
+		t.Errorf("intended = %v, must %v: want anchor's mail and web, nothing elsewhere, every node answering", got, must)
+	}
+
+	at := time.Date(2026, 10, 27, 2, 0, 0, 0, time.UTC)
+	p := delivery.PlacementProposal{ID: "p-one", By: "op", Why: "move web", Written: at, Base: map[string]uint64{"anchor": 3, "laptop": 0},
+		Must: []string{"anchor", "laptop"}}
+	revisions := map[string]uint64{"anchor": 7, "laptop": 8}
+	intended := map[string]map[string]bool{"anchor": {"web": true}}
+	same := func(rev uint64) *delivery.CandidateAnswer {
+		return &delivery.CandidateAnswer{Proposal: "p-one", Revision: rev, Verdict: delivery.CandidateSame, Same: []string{"mail"}}
+	}
+	differs := func(rev uint64, module string) *delivery.CandidateAnswer {
+		return &delivery.CandidateAnswer{Proposal: "p-one", Revision: rev, Verdict: delivery.CandidateDiffers,
+			Differs: []delivery.ModuleDiffers{{Module: module, Why: "the port differs"}}}
+	}
+	for _, row := range []struct {
+		name    string
+		seed    bool
+		answers map[string]*delivery.CandidateAnswer
+		pulsing map[string]bool
+		state   string
+		words   string
+		marked  string
+	}{
+		{"all the same", false, map[string]*delivery.CandidateAnswer{"anchor": same(7), "laptop": same(8)}, nil, delivery.VerdictPass, "", ""},
+		{"a module added where intended", false, map[string]*delivery.CandidateAnswer{"anchor": {Proposal: "p-one", Revision: 7, Verdict: delivery.CandidateDiffers,
+			Added: []delivery.ModuleAdded{{Module: "web", Unissued: []string{"its own secret"}}}}, "laptop": same(8)}, nil, delivery.VerdictPass, "", ""},
+		{"a difference not computed passes, marked", false, map[string]*delivery.CandidateAnswer{"anchor": differs(7, "mail"), "laptop": same(8)}, nil, delivery.VerdictPass, "", "mail"},
+		{"the seed carries a difference, named", true, map[string]*delivery.CandidateAnswer{"anchor": same(7), "laptop": {Proposal: "p-one", Revision: 8,
+			Verdict: delivery.CandidateDiffers, Differs: []delivery.ModuleDiffers{{Module: "node-tools", Resource: "node-tools.runtime", Why: "the resource differs",
+				Bodies: []delivery.ResourceBodies{{ID: "node-tools.runtime", Paths: []string{"env.MESH_OWNED_PATHS./etc/resolv.conf", "env.MESH_TOOL_MODULES"},
+					Running:  `{"env":{"MESH_OWNED_PATHS":"{\"/etc/hosts\":\"hostname\",\"/etc/resolv.conf\":\"networkmanager (node-uplink)\"}"}}`,
+					Composed: `{"env":{"MESH_OWNED_PATHS":"{\"/etc/hosts\":\"hostname\",\"/etc/resolv.conf\":\"systemd-resolved (node-resolver)\"}","MESH_TOOL_MODULES":"… (cut at 8192 bytes)`}}}}}}, nil, delivery.VerdictPass, "", ""},
+		{"a refusal", false, map[string]*delivery.CandidateAnswer{"anchor": same(7), "laptop": {Proposal: "p-one", Revision: 8, Verdict: delivery.CandidateRefused,
+			Refusals: []delivery.ModuleRefused{{Module: "web", Why: "no own secret"}}}}, nil, delivery.VerdictFail, "laptop refuses", ""},
+		{"a node not answering, within its bound", false, map[string]*delivery.CandidateAnswer{"anchor": same(7)}, map[string]bool{"laptop": true}, delivery.VerdictWaits, "laptop (offline)", ""},
+		{"an answer of an earlier revision, past its bound, is no answer and decided without it", false, map[string]*delivery.CandidateAnswer{"anchor": same(6), "laptop": same(8)}, nil, delivery.VerdictPass, "no answer from anchor", ""},
+		{"a module held as today passes, shown in the brief", false, map[string]*delivery.CandidateAnswer{"anchor": same(7), "laptop": {Proposal: "p-one", Revision: 8,
+			Verdict: delivery.CandidateSame, Held: []delivery.ModuleRefused{{Module: "spiegel", Why: "a required value is unset"}}}}, nil, delivery.VerdictPass, "", ""},
+		{"its later answer", false, map[string]*delivery.CandidateAnswer{"anchor": same(7), "laptop": same(8)}, nil, delivery.VerdictPass, "", ""},
+	} {
+		q := p
+		q.Seed = row.seed
+		v := JudgeAnswers(q, intended, row.answers, revisions, map[string]bool{"anchor": true}, row.pulsing, at)
+		all := strings.Join(append(append([]string{}, v.Fails...), v.Notes...), "; ")
+		if v.State != row.state || !strings.Contains(all, row.words) {
+			t.Errorf("%s: %s, %q", row.name, v.State, all)
+		}
+		if row.seed && row.state == delivery.VerdictPass && !strings.Contains(Brief(q, v), "the seed carries: node-tools: MESH_OWNED_PATHS[/etc/resolv.conf] networkmanager (node-uplink) → (value cut) (and 1 more fields)") {
+			t.Errorf("%s: the brief does not name it: %s", row.name, Brief(q, v))
+		}
+		if row.seed && row.state == delivery.VerdictPass {
+			whole := row.answers["laptop"].Differs[0]
+			whole.Bodies = []delivery.ResourceBodies{{ID: "r", Paths: []string{"env.MESH_OWNED_PATHS./etc/resolv.conf"},
+				Running:  `{"env":{"MESH_OWNED_PATHS":"{\"/etc/resolv.conf\":\"networkmanager (node-uplink)\"}"}}`,
+				Composed: `{"env":{"MESH_OWNED_PATHS":"{\"/etc/resolv.conf\":\"systemd-resolved (node-resolver)\"}"}}`}}
+			if got := differenceWords(whole); got != "node-tools: MESH_OWNED_PATHS[/etc/resolv.conf] networkmanager (node-uplink) → systemd-resolved (node-resolver)" {
+				t.Errorf("the difference is named %q", got)
+			}
+		}
+		if strings.HasPrefix(row.name, "a module held as today") && !strings.Contains(Brief(q, v), "stays as today: spiegel (held)") {
+			t.Errorf("%s: the brief does not show it: %s", row.name, Brief(q, v))
+		}
+		if row.marked != "" && (!slices.Contains(v.Unintended["anchor"], row.marked) || !strings.Contains(Brief(q, v), "not computed: "+row.marked)) {
+			t.Errorf("%s: the difference is not marked: %+v, %s", row.name, v.Unintended, Brief(q, v))
+		}
+	}
+}

modules/mesh-delivery-assigner/manifest_test.go

@@ -8,6 +8,8 @@ import (
 
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
+
+	"git.novox.be/novox/mesh-sdk/go/views"
 )
 
 func load(t *testing.T) catalogue.Manifest {
@@ -16,9 +18,9 @@ func load(t *testing.T) catalogue.Manifest {
 	if err != nil {
 		t.Fatal(err)
 	}
-	m, err := catalogue.ParseManifest(raw)
+	m, err := catalogue.Decode(raw)
 	if err != nil {
-		t.Fatalf("mesh-sdk's manifest reader refuses the manifest: %v", err)
+		t.Fatalf("mesh-sdk cannot decode the manifest: %v", err)
 	}
 	return m
 }
@@ -33,9 +35,13 @@ func TestManifest(t *testing.T) {
 	}
 	reads := slices.Clone(m.Reads)
 	slices.Sort(reads)
-	want := []string{"mesh-build-go.steps", "mesh-config.resolved", "mesh-controller.assignments", "mesh-controller.builds", "mesh-controller.composed", "mesh-controller.grants",
-		"mesh-delivery-builder.builds", "mesh-delivery-indexer.candidates", "mesh-delivery-indexer.manifests",
-		"mesh-delivery-indexer.modules", "mesh-delivery-teller.answers", "mesh-delivery-watchman.presence", "node-engine.have"}
+	// ADR 0593 §8: it composes nothing, so it reads no candidate, held or resolved value, compose step or build log; it reads
+	// every node's published compositions to compare them, and the gate's source and merges, for the release that carries a build (ADR 0601 §1).
+	// DLV-F2r (ADR 0615 §1, ADR 0631 §1): the indexer's manifests, modules and module graph (whose verb edges a want waits
+	// on, ADR 0614 §2, §3) are read through its first views and views family, none of the indexer's states by reads.
+	want := []string{"mesh-delivery-builder.builds", "mesh-delivery-gate.merges", "mesh-delivery-gate.source",
+		"mesh-delivery-teller.answers", "mesh-delivery-watchman.presence", "mesh-grants.grants", "mesh-host.composed",
+		"mesh-provisioner.provisions", "node-engine.have"}
 	if !reflect.DeepEqual(reads, want) {
 		t.Errorf("reads = %v, want exactly %v", reads, want)
 	}
@@ -43,8 +49,9 @@ func TestManifest(t *testing.T) {
 	for _, s := range m.State {
 		states[s.Name] = s.History
 	}
-	if want := map[string]int{"asks": 5, "compositions": 5, "differences": 64, "puts": 20, "wants": 20,
-		"placement": 64, "proposals": 5, "candidates": 5, "pulses": 0}; !reflect.DeepEqual(states, want) {
+	if want := map[string]int{"asks": 5, "differences": 64, "puts": 20, "wants": 20,
+		"placement": 64, "proposals": 5, "candidates": 5, "pulses": 0, "findings": 5, "policies": 20, "seat-holders": 5, views.MarksState: 1, views.StatusState: 1,
+		"engine-reads": 1}; !reflect.DeepEqual(states, want) {
 		t.Errorf("state = %v, want %v", states, want)
 	}
 	if _, ok := m.OwnSecrets["broker"]; !ok || len(m.OwnSecrets) != 1 {
@@ -53,33 +60,64 @@ func TestManifest(t *testing.T) {
 	if m.SecretsOwner != "mesh-delivery-assigner" {
 		t.Errorf("secrets-owner = %q", m.SecretsOwner)
 	}
-	// 1906/D3: it says its conditions on the operator channel; 1622: it puts its compose asks on the Go build seat, as the
-	// checker puts its checks.
-	if !slices.Equal(m.Uses, []string{"node-build-go", "operator-channel"}) {
-		t.Errorf("uses = %v, want exactly node-build-go and operator-channel", m.Uses)
+	// 1906/D3: it says its conditions on the operator channel; it asks the Go build seat nothing since the composition is
+	// the node-engine's (ADR 0593 §7).
+	if !slices.Equal(m.Uses, []string{"operator-channel"}) {
+		t.Errorf("uses = %v, want exactly operator-channel", m.Uses)
 	}
 	// ADR 0546: it serves its own tools (put, release, puts) from its bundle through the tool runner (the artifact loads the
-	// module), says each put's step as the event put, and calls the controller's warranted and the bus node's backup holder.
-	// ADR 0567 §1, §6-§10: it holds the seat mesh-placement, serving its seven verbs; keeps the seat's events on its stream
-	// placement for 30 days; calls the controller's export, its four verbs that keep its assignments in step and its
-	// hand-act log; and reads mesh-config's resolved values to compose every node a proposal touches.
-	if len(m.Claims) != 1 || m.Claims[0].Name != catalogue.PlacementSeat || m.Claims[0].At() != catalogue.ScopeMesh ||
-		!slices.Equal(m.Claims[0].Serves, []string{"placement", "proposals", "propose", "withdraw", "again", "adopt", "hand-back"}) {
-		t.Errorf("the assigner claims %+v, want mesh-placement with its seven verbs", m.Claims)
+	// module), says each put's step as the event put, and calls the hand-act seat and the bus node's backup holder.
+	// ADR 0567 §1, §6-§10: it holds the seat mesh-placement, serving its five verbs (adopt and hand-back went with the
+	// controller, ADR 0590); keeps the seat's events on its stream placement for 30 days; calls the hand-act log; and reads
+	// mesh-config's resolved values to compose every node a proposal touches.
+	// ADR 0565 §7, §9 (issue 1953 D4): and the seat mesh-wants, serving upgrade and bus.
+	if len(m.Claims) != 2 || m.Claims[0].Name != catalogue.PlacementSeat || m.Claims[0].At() != catalogue.ScopeMesh ||
+		!slices.Equal(m.Claims[0].Serves, []string{"placement", "proposals", "propose", "withdraw", "again"}) ||
+		m.Claims[1].Name != catalogue.WantsSeat || m.Claims[1].At() != catalogue.ScopeMesh || !slices.Equal(m.Claims[1].Serves, []string{"upgrade", "bus"}) {
+		t.Errorf("the assigner claims %+v, want mesh-placement with its five verbs and mesh-wants with its two", m.Claims)
+	}
+	if seat, _ := catalogue.SeatNamed(catalogue.WantsSeat); catalogue.CanHold(m, seat) != nil {
+		t.Errorf("the assigner cannot hold mesh-wants: %v", catalogue.CanHold(m, seat))
 	}
 	if seat, _ := catalogue.SeatNamed(catalogue.PlacementSeat); catalogue.CanHold(m, seat) != nil {
 		t.Errorf("the assigner cannot hold the seat: %v", catalogue.CanHold(m, seat))
 	}
-	if !slices.Equal(m.Tools, []string{"assigner_put", "assigner_release", "assigner_puts"}) {
-		t.Errorf("the assigner serves tools %v, want its three put tools", m.Tools)
+	// ADR 0621 §1: the first-view tools placement, seat-holders and wants and design 25 § 12.2's six read tools, of the
+	// program's bundle, which runs in a runtime of its own on the assigner's account; ADR 0618 §3: and assigner_engine_reads,
+	// which lists and asks again what each node's engine reads.
+	if !slices.Equal(m.Tools, []string{"assigner_put", "assigner_release", "assigner_puts", "placement", "seat-holders", "wants",
+		"assigner_read_placement", "assigner_read_seat_holders", "assigner_read_wants", "assigner_read_findings", "assigner_read_asks", "assigner_read_differences",
+		"assigner_first_views", "assigner_first_view_again", "assigner_engine_reads"}) {
+		t.Errorf("the assigner serves tools %v, want its three put tools, three first views, six read tools and assigner_engine_reads", m.Tools)
 	}
-	if len(m.Streams) != 1 || m.Streams[0].Name != delivery.PlacementStream || m.Streams[0].MaxAgeDays != delivery.PlacementStreamDays ||
+	if m.RunsAs != m.Module || m.SecretsOwner != m.RunsAs {
+		t.Errorf("runs-as = %q: the bundle runs on the assigner's own account (ADR 0621 §1)", m.RunsAs)
+	}
+	// ADR 0621 §2: each first-view tool answers exactly its readers, never the assigner.
+	callers := map[string]string{"placement": "mesh-grants,node-tools,mesh-delivery-indexer", "seat-holders": "node-tools", "wants": "mesh-grants"}
+	env := m.Build.Artifacts[0].Env
+	for tool, list := range callers {
+		if env[views.CallersEnv(tool)] != list || views.ParseCallers(env[views.CallersEnv(tool)]).Allows("n1."+m.Module) {
+			t.Errorf("%s callers = %q, want %q", tool, env[views.CallersEnv(tool)], list)
+		}
+	}
+	// ADR 0619 §2, ADR 0615 §5: its views family beside placement on its old streams section.
+	if len(m.Streams) != 2 || m.Streams[1].Name != "assigner-views" || !slices.Equal(m.Streams[1].Events, []string{views.EventPattern}) ||
+		m.Streams[1].MaxAgeDays != views.StreamDays || m.Streams[1].MaxMiB != views.StreamMiB || m.Streams[1].Retention != "" {
+		t.Errorf("streams = %+v, want placement and assigner-views", m.Streams)
+	}
+	if m.Streams[0].Name != delivery.PlacementStream || m.Streams[0].MaxAgeDays != delivery.PlacementStreamDays ||
 		!slices.Equal(slices.Sorted(slices.Values(m.Streams[0].Events)), slices.Sorted(slices.Values(delivery.PlacementEvents))) {
 		t.Errorf("streams = %+v, want placement carrying the seat's four events for %d days", m.Streams, delivery.PlacementStreamDays)
 	}
-	if want := []string{"seat:mesh-controller.assign", "seat:mesh-controller.hand-act", "seat:mesh-controller.pin",
-		"seat:mesh-controller.placement-export", "seat:mesh-controller.unassign", "seat:mesh-controller.unpin",
-		"seat:mesh-controller.warranted", "seat:node-backup.backed-up", "seat:node-backup.now"}; !slices.Equal(slices.Sorted(slices.Values(m.Invokes)), want) {
+	// ADR 0618 §4: and it hears each node's engine say its reads changed.
+	if !slices.Equal(m.Consumes, []string{"mesh-delivery-indexer.views.graph", "mesh-delivery-indexer.views.manifests", "mesh-delivery-indexer.views.modules", "node-engine.manifest-reads-changed"}) {
+		t.Errorf("consumes = %v, want the indexer's views of graph, manifests and modules and the engines' reads changed", m.Consumes)
+	}
+	if want := []string{"mesh-delivery-indexer.graph", "mesh-delivery-indexer.manifests", "mesh-delivery-indexer.modules",
+		"seat:mesh-hand-acts.hand-act", "seat:mesh-hand-acts.hand-acts", "seat:mesh-hand-acts.warranted", // ADR 0565 §9, §11: the seat alone
+		"seat:node-backup.backed-up", "seat:node-backup.now",
+		"seat:node-engine.manifest-reads"}; !slices.Equal(slices.Sorted(slices.Values(m.Invokes)), want) { // ADR 0618 §3
 		t.Errorf("invokes = %v, want %v", m.Invokes, want)
 	}
 	if !slices.Equal(m.Emits, []string{"put"}) {

modules/mesh-delivery-assigner/module.json

@@ -2,6 +2,7 @@
   "module": "mesh-delivery-assigner",
   "version": "1",
   "slug": "assigner",
+  "runs-as": "mesh-delivery-assigner",
   "claims": [
     {
       "name": "mesh-placement",
@@ -11,41 +12,48 @@
         "proposals",
         "propose",
         "withdraw",
-        "again",
-        "adopt",
-        "hand-back"
+        "again"
+      ]
+    },
+    {
+      "name": "mesh-wants",
+      "scope": "mesh",
+      "serves": [
+        "upgrade",
+        "bus"
       ]
     }
   ],
   "reads": [
-    "mesh-build-go.steps",
-    "mesh-config.resolved",
-    "mesh-controller.assignments",
-    "mesh-controller.builds",
-    "mesh-controller.composed",
-    "mesh-controller.grants",
     "mesh-delivery-builder.builds",
-    "mesh-delivery-indexer.candidates",
-    "mesh-delivery-indexer.manifests",
-    "mesh-delivery-indexer.modules",
+    "mesh-delivery-gate.merges",
+    "mesh-delivery-gate.source",
     "mesh-delivery-teller.answers",
     "mesh-delivery-watchman.presence",
+    "mesh-grants.grants",
+    "mesh-host.composed",
+    "mesh-provisioner.provisions",
     "node-engine.have"
   ],
   "uses": [
-    "node-build-go",
     "operator-channel"
   ],
+  "consumes": [
+    "mesh-delivery-indexer.views.graph",
+    "mesh-delivery-indexer.views.manifests",
+    "mesh-delivery-indexer.views.modules",
+    "node-engine.manifest-reads-changed"
+  ],
   "invokes": [
-    "seat:mesh-controller.assign",
-    "seat:mesh-controller.hand-act",
-    "seat:mesh-controller.pin",
-    "seat:mesh-controller.placement-export",
-    "seat:mesh-controller.unassign",
-    "seat:mesh-controller.unpin",
-    "seat:mesh-controller.warranted",
+    "mesh-delivery-indexer.graph",
+    "mesh-delivery-indexer.manifests",
+    "mesh-delivery-indexer.modules",
+    "seat:mesh-hand-acts.hand-act",
+    "seat:mesh-hand-acts.hand-acts",
+    "seat:mesh-hand-acts.warranted",
     "seat:node-backup.backed-up",
-    "seat:node-backup.now"
+    "seat:node-backup.now",
+    "seat:node-engine.manifest-reads"
   ],
   "emits": [
     "put"
@@ -53,7 +61,19 @@
   "tools": [
     "assigner_put",
     "assigner_release",
-    "assigner_puts"
+    "assigner_puts",
+    "placement",
+    "seat-holders",
+    "wants",
+    "assigner_read_placement",
+    "assigner_read_seat_holders",
+    "assigner_read_wants",
+    "assigner_read_findings",
+    "assigner_read_asks",
+    "assigner_read_differences",
+    "assigner_first_views",
+    "assigner_first_view_again",
+    "assigner_engine_reads"
   ],
   "state": [
     { "name": "placement", "history": 64 },
@@ -61,10 +81,15 @@
     { "name": "candidates", "history": 5 },
     { "name": "pulses", "key-ttl": true },
     { "name": "asks", "history": 5 },
-    { "name": "compositions", "history": 5 },
     { "name": "differences", "history": 64 },
     { "name": "puts", "history": 20 },
-    { "name": "wants", "history": 20 }
+    { "name": "wants", "history": 20 },
+    { "name": "findings", "history": 5 },
+    { "name": "policies", "history": 20 },
+    { "name": "seat-holders", "history": 5 },
+    { "name": "view-marks", "history": 1 },
+    { "name": "first-views", "history": 1 },
+    { "name": "engine-reads", "history": 1 }
   ],
   "streams": [
     {
@@ -76,7 +101,8 @@
         "placement-withdrawn"
       ],
       "max-age-days": 30
-    }
+    },
+    { "name": "assigner-views", "events": ["views.**"], "max-age-days": 7, "max-mib": 256 }
   ],
   "own-secrets": {
     "broker": "${dir:state}/broker"
@@ -126,7 +152,12 @@
         "binary": "mesh-delivery-assigner",
         "loads": [
           "mesh-delivery-assigner"
-        ]
+        ],
+        "env": {
+          "MESH_VIEW_CALLERS_PLACEMENT": "mesh-grants,node-tools,mesh-delivery-indexer",
+          "MESH_VIEW_CALLERS_SEAT_HOLDERS": "node-tools",
+          "MESH_VIEW_CALLERS_WANTS": "mesh-grants"
+        }
       }
     ]
   }

modules/mesh-delivery-builder/buildrun/asks.go

@@ -0,0 +1,316 @@
+package buildrun
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/nats-io/nats.go"
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// **An asker puts an ask on its build seat's stream and waits for its step** (novox/hq ADR 0525 §1, §6; issue 1887 A4,
+// A5). It chooses no node: whichever build node pulls the ask writes `<node>.<ask id>` in its build module's steps state,
+// and the asker reads the first such key that is not running. The builder and the checker share it.
+
+// AskPublisher puts an encoded ask on subject, de-duplicated by its id.
+type AskPublisher interface {
+	PublishAsk(ctx context.Context, subject, id string, data []byte) error
+}
+
+// AskWaiter watches an ask's steps: every value a key `*.<ask id>` of the build module's steps state takes, running or
+// ended, on the channel it answers, until ctx ends. A watch, not a poll.
+type AskWaiter interface {
+	WatchAsk(ctx context.Context, module, askID string) (<-chan delivery.Step, error)
+}
+
+// Asker puts asks and waits for their steps.
+type Asker struct {
+	Publisher AskPublisher
+	Waiter    AskWaiter
+	// Bound is how long a running step (a build node took the ask, its key written running) may stand still, with no new phase,
+	// before the asker stops waiting; a step that keeps moving is waited for up to 3 Bounds from its start (issue 1930); zero waits as long as ctx. An ask waiting in its stream is not bounded: the stream's backlog is no fault
+	// (ADR 0525 §6, §9), and the bound starts again when another node takes the ask.
+	Bound time.Duration
+}
+
+// Put puts a on its stream: the seat's accept subject of its language and kind.
+func (k Asker) Put(ctx context.Context, a delivery.StepAsk) error {
+	raw, err := delivery.EncodeStepAsk(a)
+	if err != nil {
+		return err
+	}
+	subject, err := delivery.AskSubject(a.Language, a.Kind)
+	if err != nil {
+		return err
+	}
+	if err := k.Publisher.PublishAsk(ctx, subject, a.ID, raw); err != nil {
+		return fmt.Errorf("putting the %s ask %s: %w", a.Kind, a.ID, err)
+	}
+	return nil
+}
+
+// Wait waits for the step of an ask already put (a builder that started again takes over its own asks with it, never
+// putting them twice) and answers it when it ended, whatever its state. The bound runs from the step's start on the node
+// that took the ask, read from its running key, so an ask that waits in the stream for a free slot waits as long as ctx.
+func (k Asker) Wait(ctx context.Context, a delivery.StepAsk) (delivery.Step, error) {
+	module, err := delivery.BuildModuleOf(a.Language)
+	if err != nil {
+		return delivery.Step{}, err
+	}
+	watch, cancel := context.WithCancel(ctx)
+	defer cancel()
+	steps, err := k.Waiter.WatchAsk(watch, module, a.ID)
+	if err != nil {
+		return delivery.Step{}, err
+	}
+	var bound, outerCap <-chan time.Time
+	var timer, capTimer *time.Timer
+	defer func() {
+		if timer != nil {
+			timer.Stop()
+		}
+		if capTimer != nil {
+			capTimer.Stop()
+		}
+	}()
+	running, since, phase, phaseAt := "", time.Time{}, "", time.Time{}
+	standStill := func() error {
+		if phase == "" {
+			return fmt.Errorf("the ask %s's step on %s did not end within %s of its start: it stood still, saying no phase", a.ID, running, k.Bound)
+		}
+		return fmt.Errorf("the ask %s's step on %s did not end within %s: it stood still in %q since %s",
+			a.ID, running, k.Bound, phase, phaseAt.UTC().Format(time.RFC3339))
+	}
+	for {
+		select {
+		case <-ctx.Done():
+			return delivery.Step{}, ctx.Err()
+		case <-bound:
+			return delivery.Step{}, standStill()
+		case <-outerCap:
+			return delivery.Step{}, fmt.Errorf("the ask %s's step on %s did not end within %s of its start: it kept moving (last phase %q at %s) but never ended",
+				a.ID, running, 3*k.Bound, phase, phaseAt.UTC().Format(time.RFC3339))
+		case step, ok := <-steps:
+			if !ok {
+				return delivery.Step{}, errors.New("the watch of the ask's step ended")
+			}
+			if seen := stepSeenOf(ctx); seen != nil {
+				seen(step)
+			}
+			if step.State != delivery.StepRunning {
+				return step, nil
+			}
+			if k.Bound <= 0 {
+				continue
+			}
+			newRun := step.Node != running || !step.Started.Equal(since)
+			if !newRun && step.Phase == phase && step.PhaseAt.Equal(phaseAt) {
+				continue
+			}
+			// A node took the ask, or took it again after its run stopped (another node, or the same node's build module
+			// replaced mid-run: a new start), or its step entered a phase. The bound is on standing still: it runs from the
+			// step's last movement (its phase's start, else its start), so a step that keeps moving is waited for, up to
+			// three bounds from its start (issue 1930).
+			running, since, phase, phaseAt = step.Node, step.Started, step.Phase, step.PhaseAt
+			last := step.Started
+			if step.PhaseAt.After(last) {
+				last = step.PhaseAt
+			}
+			left := k.Bound
+			if !last.IsZero() {
+				left = time.Until(last.Add(k.Bound))
+			}
+			if timer != nil {
+				timer.Stop()
+			}
+			timer = time.NewTimer(max(left, 0))
+			bound = timer.C
+			if newRun {
+				if capTimer != nil {
+					capTimer.Stop()
+				}
+				outer := 3 * k.Bound
+				if !step.Started.IsZero() {
+					outer = time.Until(step.Started.Add(3 * k.Bound))
+				}
+				capTimer = time.NewTimer(max(outer, 0))
+				outerCap = capTimer.C
+			}
+		}
+	}
+}
+
+type stepSeenKey struct{}
+
+// WithStepSeen is ctx carrying seen, which Asker.Wait hands every value the ask's step key takes while it waits: the node
+// that took it, each phase it says while running (delivery.Step.Phase), and its end. A try names its asks' progress so
+// (issue 1890). seen runs in the waiting goroutine and must not block.
+func WithStepSeen(ctx context.Context, seen func(delivery.Step)) context.Context {
+	return context.WithValue(ctx, stepSeenKey{}, seen)
+}
+
+func stepSeenOf(ctx context.Context) func(delivery.Step) {
+	seen, _ := ctx.Value(stepSeenKey{}).(func(delivery.Step))
+	return seen
+}
+
+// Ask puts a and waits for its step; a step that did not pass is an error naming its node, its state and its reason.
+func (k Asker) Ask(ctx context.Context, a delivery.StepAsk) (delivery.Step, error) {
+	if err := k.Put(ctx, a); err != nil {
+		return delivery.Step{}, err
+	}
+	return k.Passed(k.Wait(ctx, a))
+}
+
+// Passed is step when it passed, else an error naming where it ended and why.
+func (k Asker) Passed(step delivery.Step, err error) (delivery.Step, error) {
+	if err != nil {
+		return step, err
+	}
+	if step.State != delivery.StepPassed {
+		return step, fmt.Errorf("the ask %s on %s %s: %s", step.ID, step.Node, step.State, step.Reason)
+	}
+	return step, nil
+}
+
+// JetStreamAsks is the bus side of an Asker: a JetStream publish de-duplicated by the ask's id (Nats-Msg-Id), and a watch
+// of `*.<ask id>` in the build module's steps bucket.
+type JetStreamAsks struct {
+	JS jetstream.JetStream
+}
+
+// PublishAsk is AskPublisher's.
+func (s JetStreamAsks) PublishAsk(ctx context.Context, subject, id string, data []byte) error {
+	msg := &nats.Msg{Subject: subject, Data: data, Header: nats.Header{}}
+	msg.Header.Set(jetstream.MsgIDHeader, id)
+	_, err := s.JS.PublishMsg(ctx, msg)
+	return err
+}
+
+// WatchAsk is AskWaiter's: the watch hands over what the keys hold now, so a step that ended before it began is read at
+// once, and every change after.
+func (s JetStreamAsks) WatchAsk(ctx context.Context, module, askID string) (<-chan delivery.Step, error) {
+	pattern, err := delivery.AskStepWatch(askID)
+	if err != nil {
+		return nil, err
+	}
+	kv, err := s.JS.KeyValue(ctx, delivery.StepsBucket(module))
+	if err != nil {
+		return nil, fmt.Errorf("the bucket %s: %w", delivery.StepsBucket(module), err)
+	}
+	w, err := kv.Watch(ctx, pattern)
+	if err != nil {
+		return nil, err
+	}
+	out := make(chan delivery.Step)
+	go func() {
+		defer close(out)
+		defer w.Stop()
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			case e, ok := <-w.Updates():
+				if !ok {
+					return
+				}
+				if e == nil || e.Operation() != jetstream.KeyValuePut {
+					continue
+				}
+				step, err := delivery.DecodeStep(e.Value())
+				if err != nil {
+					continue // not a step (a node's pause key never matches an ask id; anything else is not this ask's)
+				}
+				select {
+				case out <- step:
+				case <-ctx.Done():
+					return
+				}
+			}
+		}
+	}()
+	return out, nil
+}
+
+// FakeAsks is a test double of the bus for an asker's tests: each ask put is kept and, when Answer is set, its step is
+// written at once with what Answer says a build node wrote (running or ended). Write writes a step later. Safe for
+// concurrent use.
+type FakeAsks struct {
+	Answer func(a delivery.StepAsk) delivery.Step
+
+	mu       sync.Mutex
+	asks     []delivery.StepAsk
+	steps    map[string][]delivery.Step
+	watchers map[string][]chan delivery.Step
+}
+
+// PublishAsk is AskPublisher's.
+func (f *FakeAsks) PublishAsk(_ context.Context, _, id string, data []byte) error {
+	a, err := delivery.DecodeStepAsk(data)
+	if err != nil {
+		return err
+	}
+	f.mu.Lock()
+	f.asks = append(f.asks, a)
+	f.mu.Unlock()
+	if f.Answer != nil {
+		f.Write(f.Answer(a))
+	}
+	return nil
+}
+
+// Write writes an ask's step, as a build node does.
+func (f *FakeAsks) Write(step delivery.Step) {
+	f.mu.Lock()
+	if f.steps == nil {
+		f.steps, f.watchers = map[string][]delivery.Step{}, map[string][]chan delivery.Step{}
+	}
+	f.steps[step.ID] = append(f.steps[step.ID], step)
+	ws := append([]chan delivery.Step(nil), f.watchers[step.ID]...)
+	f.mu.Unlock()
+	for _, w := range ws {
+		w <- step
+	}
+}
+
+// End is Write: kept for the tests that end a step.
+func (f *FakeAsks) End(step delivery.Step) { f.Write(step) }
+
+// WatchAsk is AskWaiter's: what was written so far, then every write.
+func (f *FakeAsks) WatchAsk(ctx context.Context, _ string, askID string) (<-chan delivery.Step, error) {
+	out := make(chan delivery.Step, 64)
+	f.mu.Lock()
+	if f.steps == nil {
+		f.steps, f.watchers = map[string][]delivery.Step{}, map[string][]chan delivery.Step{}
+	}
+	for _, s := range f.steps[askID] {
+		out <- s
+	}
+	f.watchers[askID] = append(f.watchers[askID], out)
+	f.mu.Unlock()
+	go func() {
+		<-ctx.Done()
+		f.mu.Lock()
+		ws := f.watchers[askID]
+		for i, w := range ws {
+			if w == out {
+				f.watchers[askID] = append(ws[:i], ws[i+1:]...)
+				break
+			}
+		}
+		f.mu.Unlock()
+	}()
+	return out, nil
+}
+
+// Asks are the asks put so far.
+func (f *FakeAsks) Asks() []delivery.StepAsk {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	return append([]delivery.StepAsk(nil), f.asks...)
+}

modules/mesh-delivery-builder/buildrun/asks_integration_test.go

@@ -0,0 +1,61 @@
+//go:build integration
+
+package buildrun
+
+import (
+	"context"
+	"encoding/json"
+	"testing"
+	"time"
+
+	"github.com/nats-io/nats.go"
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/testbus"
+)
+
+// 1887/A4a, 1887/AC3 on the real bus: an ask put twice under one id is one message, and the asker reads the step a node
+// wrote under `<node>.<ask id>`.
+func TestAnAskIsPutOnceAndItsStepIsRead(t *testing.T) {
+	nc, err := nats.Connect(testbus.URL(t))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer nc.Close()
+	js, _ := jetstream.New(nc)
+	ctx := context.Background()
+	if _, err := js.CreateStream(ctx, jetstream.StreamConfig{Name: "SEAT_NODE_BUILD_GO", Subjects: []string{"mesh.seat.node-build-go.accept.>"},
+		Retention: jetstream.WorkQueuePolicy}); err != nil {
+		t.Fatal(err)
+	}
+	kv, err := js.CreateKeyValue(ctx, jetstream.KeyValueConfig{Bucket: delivery.StepsBucket("mesh-build-go")})
+	if err != nil {
+		t.Fatal(err)
+	}
+	bus := JetStreamAsks{JS: js}
+	k := Asker{Publisher: bus, Waiter: bus, Bound: 5 * time.Second}
+	a := goAsk("mvl0frv18d1960")
+	for i := 0; i < 2; i++ {
+		if err := k.Put(ctx, a); err != nil {
+			t.Fatal(err)
+		}
+	}
+	s, _ := js.Stream(ctx, "SEAT_NODE_BUILD_GO")
+	if info, _ := s.Info(ctx); info.State.Msgs != 1 {
+		t.Fatalf("%d messages for one ask put twice", info.State.Msgs)
+	}
+	go func() {
+		time.Sleep(100 * time.Millisecond)
+		key, _ := delivery.AskStepKey("ace", a.ID)
+		running, _ := delivery.EncodeStep(delivery.Step{ID: a.ID, Tool: "delivery ask", Node: "ace", State: delivery.StepRunning, Started: time.Now()})
+		_, _ = kv.Put(ctx, key, running)
+		passed, _ := delivery.EncodeStep(delivery.Step{ID: a.ID, Tool: "delivery ask", Node: "ace", State: delivery.StepPassed, Started: time.Now(),
+			Result: json.RawMessage(`{"artifacts":[]}`)})
+		_, _ = kv.Put(ctx, key, passed)
+	}()
+	step, err := k.Passed(k.Wait(ctx, a))
+	if err != nil || step.Node != "ace" {
+		t.Fatalf("step %+v, %v", step, err)
+	}
+}

modules/mesh-delivery-builder/buildrun/asks_test.go

@@ -0,0 +1,234 @@
+package buildrun
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/health"
+)
+
+func goAsk(id string) delivery.StepAsk {
+	return delivery.StepAsk{ID: id, Kind: delivery.AskDelivery, Language: delivery.AskGo, Asker: "mesh-delivery-builder", At: time.Now(),
+		Build: &delivery.BuildJob{Module: "m", Path: ".", Fetch: map[string]any{"repository": "novox/x", "commit": strings.Repeat("a", 40)},
+			Artifacts: []delivery.AskArtifact{{Artifact: "program"}}}}
+}
+
+// 1887/A4a: an asker puts the ask once and answers the step a build node wrote for it, naming the node; one that did not
+// pass is an error naming the node and why; a wait of an ask already put puts nothing.
+func TestAnAskerPutsOnceAndReadsTheStep(t *testing.T) {
+	f := &FakeAsks{Answer: func(a delivery.StepAsk) delivery.Step {
+		return delivery.Step{ID: a.ID, Node: "ace", State: delivery.StepPassed, Result: []byte(`{"artifacts":[]}`)}
+	}}
+	k := Asker{Publisher: f, Waiter: f}
+	var seen []delivery.Step // issue 1890: a waiter that asks to see each value of the step sees it
+	step, err := k.Ask(WithStepSeen(context.Background(), func(s delivery.Step) { seen = append(seen, s) }), goAsk("mvl0frv18d1957"))
+	if err != nil || step.Node != "ace" || len(f.Asks()) != 1 || len(seen) != 1 || seen[0].Node != "ace" {
+		t.Fatalf("step %+v, %v, asks %d, seen %+v", step, err, len(f.Asks()), seen)
+	}
+	f.Answer = func(a delivery.StepAsk) delivery.Step {
+		return delivery.Step{ID: a.ID, Node: "shanks", State: delivery.StepRefused, Reason: "go 1.27 installed"}
+	}
+	if _, err := k.Ask(context.Background(), goAsk("mvl0frv18d1958")); err == nil || !strings.Contains(err.Error(), "shanks refused: go 1.27 installed") {
+		t.Fatalf("a refused step: %v", err)
+	}
+	// review round 2 item 1: an ask that waits in its stream for a free slot is not bounded; once a node writes its step
+	// running, the step is bounded from its start, and the error names the node.
+	g := &FakeAsks{}
+	k = Asker{Publisher: g, Waiter: g, Bound: 20 * time.Millisecond}
+	waiting, cancel := context.WithTimeout(context.Background(), 100*time.Millisecond)
+	defer cancel()
+	if _, err := k.Wait(waiting, goAsk("mvl0frv18d1959")); err != context.DeadlineExceeded {
+		t.Fatalf("an ask no node took: %v, want it still waiting when ctx ended", err)
+	}
+	g.Write(delivery.Step{ID: "mvl0frv18d1961", Node: "ace", State: delivery.StepRunning, Started: time.Now()})
+	if _, err := k.Wait(context.Background(), goAsk("mvl0frv18d1961")); err == nil || !strings.Contains(err.Error(), "on ace did not end within") {
+		t.Fatalf("a step that never ends: %v", err)
+	}
+	if len(g.Asks()) != 0 {
+		t.Fatal("a wait put an ask")
+	}
+	// Issue 1930: the bound is on a step that stands still, not on its age. A step past one bound from its start that entered a
+	// new phase inside the bound is waited for until it ends; one that stood a whole bound in a phase fails at once, naming
+	// the phase; one three bounds from its start ends, said as kept moving. The steps' own times stand for the clock, so the
+	// bound is an hour no loaded machine reaches and no case waits on a pause (the check of 2026-11-02 22:35 tripped one
+	// of 60 ms).
+	k = Asker{Publisher: g, Waiter: g, Bound: time.Hour}
+	now := time.Now()
+	g.Write(delivery.Step{ID: "mvl0frv18d1980", Node: "ace", State: delivery.StepRunning, Started: now.Add(-90 * time.Minute), Phase: "pb", PhaseAt: now})
+	g.Write(delivery.Step{ID: "mvl0frv18d1980", Node: "ace", State: delivery.StepPassed})
+	if step, err := k.Wait(context.Background(), goAsk("mvl0frv18d1980")); err != nil || step.State != delivery.StepPassed {
+		t.Fatalf("a step that kept moving past its bound: %+v, %v", step, err)
+	}
+	g.Write(delivery.Step{ID: "mvl0frv18d1981", Node: "ace", State: delivery.StepRunning, Started: now.Add(-time.Hour), Phase: "integration: tests", PhaseAt: now.Add(-time.Hour)})
+	if _, err := k.Wait(context.Background(), goAsk("mvl0frv18d1981")); err == nil || !strings.Contains(err.Error(), `stood still in "integration: tests"`) {
+		t.Fatalf("a step that stood still in a phase: %v", err)
+	}
+	g.Write(delivery.Step{ID: "mvl0frv18d1982", Node: "ace", State: delivery.StepRunning, Started: now.Add(-3 * time.Hour), Phase: "qz", PhaseAt: now})
+	if _, err := k.Wait(context.Background(), goAsk("mvl0frv18d1982")); err == nil || !strings.Contains(err.Error(), "kept moving") {
+		t.Fatalf("a step that never stops moving: %v", err)
+	}
+	// Issue 734: an ask the build seat gave up on (DEAD_LETTERS keeps its copy with the ask's id) ends its wait as failed
+	// with the words, though a node had taken it; under NotTakenBound one no node takes ends at the bound; a step written
+	// first is answered as the node wrote it.
+	dead := &DeadLetters{}
+	lw := LostAskWaiter{Inner: g, Dead: dead}
+	k = Asker{Publisher: g, Waiter: lw, Bound: time.Minute}
+	g.Write(delivery.Step{ID: "mvl0frv18d1970", Node: "ace", State: delivery.StepRunning, Started: time.Now()})
+	given, ok := GivenUpOf(map[string][]string{"Mesh-Dead-Msg-Id": {"mvl0frv18d1970"}, "Mesh-Dead-Deliveries": {"5"},
+		"Mesh-Dead-Stream": {"SEAT_NODE_BUILD_GO"}, "Mesh-Dead-Gave-Up": {"2026-10-26T12:26:40Z"}})
+	if !ok {
+		t.Fatal("a dead letter's headers were not read")
+	}
+	go dead.Heard(given)
+	step, err = k.Wait(context.Background(), goAsk("mvl0frv18d1970"))
+	if err != nil || step.State != delivery.StepFailed || !IsLost(step) ||
+		!strings.Contains(step.Reason, LostWords+" after 5 deliveries at 2026-10-26T12:26:40Z") {
+		t.Fatalf("a given-up ask: %+v, %v", step, err)
+	}
+	if _, err := k.Passed(step, nil); err == nil || !strings.Contains(err.Error(), "on "+LostNode+" failed: "+LostWords) {
+		t.Fatalf("a given-up ask's error: %v", err)
+	}
+	step, err = k.Wait(NotTakenBound(context.Background(), 20*time.Millisecond), goAsk("mvl0frv18d1971"))
+	if err != nil || !IsNotTaken(step) || IsLost(step) {
+		t.Fatalf("an ask no node took: %+v, %v", step, err)
+	}
+	g.Write(delivery.Step{ID: "mvl0frv18d1972", Node: "g14", State: delivery.StepPassed})
+	if step, err = k.Wait(NotTakenBound(context.Background(), time.Minute), goAsk("mvl0frv18d1972")); err != nil || step.Node != "g14" {
+		t.Fatalf("a step written: %+v, %v", step, err)
+	}
+	// Review round 1 of issue 734: a hearing the bus refuses at start is deaf and says so, never holds the start up, and
+	// tries again on the next ask waited for; heard, it says so and hands the given-up asks on.
+	fol := &refusingFollower{refuse: 1}
+	var mu sync.Mutex
+	var told []Hearing
+	hearing := NewDeadLetterHearing(context.Background(), fol, []string{delivery.AskGo}, dead, nil,
+		func(h Hearing) { mu.Lock(); told = append(told, h); mu.Unlock() })
+	hearing.Wait()
+	if why := hearing.Deaf(); !strings.Contains(why, "SEAT_NODE_BUILD_GO: permissions violation") {
+		t.Fatalf("a refused hearing says %q", why)
+	}
+	k = Asker{Publisher: g, Waiter: LostAskWaiter{Inner: g, Dead: dead, Hearing: hearing}, Bound: time.Minute}
+	g.Write(delivery.Step{ID: "mvl0frv18d1973", Node: "g14", State: delivery.StepPassed})
+	if _, err := k.Wait(context.Background(), goAsk("mvl0frv18d1973")); err != nil {
+		t.Fatal(err)
+	}
+	hearing.Wait()
+	mu.Lock()
+	if hearing.Deaf() != "" || len(told) != 2 || told[0].Heard || !told[1].Heard || fol.calls() != 2 {
+		t.Fatalf("after an ask: deaf %q, told %+v, followed %d times", hearing.Deaf(), told, fol.calls())
+	}
+	mu.Unlock()
+	fol.heard(GivenUp{AskID: "mvl0frv18d1974", Deliveries: 5})
+	step, err = k.Wait(context.Background(), goAsk("mvl0frv18d1974"))
+	if err != nil || !IsLost(step) {
+		t.Fatalf("an ask heard given up after the hearing came back: %+v, %v", step, err)
+	}
+	// The lost check of 2026-10-28: a step whose own watch went deaf is read at the next nudge (a step of its build module
+	// ended) and answered; a nudge of another build module reads nothing; a watch that closes is opened again.
+	d := &FakeAsks{}
+	heard := &HeardEnds{Inner: deafWatch{}, Read: d}
+	k = Asker{Publisher: d, Waiter: heard, Bound: time.Minute}
+	d.Write(delivery.Step{ID: "mvl0frv18d1980", Node: "shanks", State: delivery.StepPassed})
+	got := make(chan delivery.Step, 1)
+	go func() { s, _ := k.Wait(context.Background(), goAsk("mvl0frv18d1980")); got <- s }()
+	for heard.Waiting() == 0 {
+		time.Sleep(time.Millisecond)
+	}
+	heard.Nudge(NodeBuildModule)
+	select {
+	case s := <-got:
+		t.Fatalf("a nudge of another build module answered %+v", s)
+	case <-time.After(20 * time.Millisecond):
+	}
+	heard.Nudge(GoBuildModule)
+	if s := <-got; s.State != delivery.StepPassed || s.Node != "shanks" {
+		t.Fatalf("a step its watch never handed over: %+v", s)
+	}
+	closing := &HeardEnds{Inner: &closingWatch{inner: d}, Read: d}
+	if s, err := (Asker{Publisher: d, Waiter: closing}).Wait(context.Background(), goAsk("mvl0frv18d1980")); err != nil || s.State != delivery.StepPassed {
+		t.Fatalf("a watch that closed once: %+v, %v", s, err)
+	}
+	for _, row := range []struct {
+		h    *Hearing
+		want string
+	}{{nil, health.StateUnhealthy}, {&told[0], health.StateUnhealthy}, {&told[1], health.StateHealthy}} {
+		var raw []byte
+		if row.h != nil {
+			raw, _ = json.Marshal(row.h)
+		}
+		if a := HearingHealth(raw); a.State != row.want || a.Why == "" {
+			t.Errorf("health of %+v = %+v, want %s", row.h, a, row.want)
+		}
+	}
+}
+
+// Review (issue 734 path): an ask taken again by the same node (its build module replaced mid-run) is bounded from the
+// new run's start, not the first run's. The steps' own times stand for the clock: the first run started now, the second a
+// whole bound ago, so the wait ends at once on the second run's bound where the first run's would wait an hour; no case
+// waits on a pause a loaded machine can outlast (the check of 2026-11-02 22:35 tripped one of 60 ms). The context's
+// bound is reached only by a wait that kept the first run's start.
+func TestARedeliveryToTheSameNodeRestartsTheBound(t *testing.T) {
+	f := &FakeAsks{}
+	k := Asker{Publisher: f, Waiter: f, Bound: time.Hour}
+	const id = "mvl0frv18d1962"
+	now := time.Now()
+	f.Write(delivery.Step{ID: id, Node: "ace", State: delivery.StepRunning, Started: now})
+	f.Write(delivery.Step{ID: id, Node: "ace", State: delivery.StepRunning, Started: now.Add(-time.Hour)})
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+	if _, err := k.Wait(ctx, goAsk(id)); err == nil || !strings.Contains(err.Error(), "on ace did not end within 1h0m0s of its start") {
+		t.Fatalf("a redelivered run a bound old: %v, want its own bound to end the wait", err)
+	}
+}
+
+// refusingFollower refuses the first `refuse` follows, as the bus does before the asker's grant is composed.
+type refusingFollower struct {
+	mu     sync.Mutex
+	refuse int
+	n      int
+	hand   func(GivenUp)
+}
+
+func (f *refusingFollower) Follow(_ context.Context, _ string, _ time.Time, heard func(GivenUp)) (func(), error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.n++
+	if f.n <= f.refuse {
+		return nil, errors.New("permissions violation")
+	}
+	f.hand = heard
+	return func() {}, nil
+}
+
+func (f *refusingFollower) calls() int { f.mu.Lock(); defer f.mu.Unlock(); return f.n }
+
+func (f *refusingFollower) heard(g GivenUp) { f.mu.Lock(); h := f.hand; f.mu.Unlock(); h(g) }
+
+// deafWatch is a watch of an ask's step that stays open and hears nothing.
+type deafWatch struct{}
+
+func (deafWatch) WatchAsk(context.Context, string, string) (<-chan delivery.Step, error) {
+	return make(chan delivery.Step), nil
+}
+
+// closingWatch closes its first watch at once, and hands the later ones to inner.
+type closingWatch struct {
+	inner  AskWaiter
+	closed bool
+}
+
+func (c *closingWatch) WatchAsk(ctx context.Context, module, askID string) (<-chan delivery.Step, error) {
+	if !c.closed {
+		c.closed = true
+		ch := make(chan delivery.Step)
+		close(ch)
+		return ch, nil
+	}
+	return c.inner.WatchAsk(ctx, module, askID)
+}

modules/mesh-delivery-builder/buildrun/choose.go

@@ -0,0 +1,88 @@
+package buildrun
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// ChooseNodes picks up to want build nodes for a language (ADR 0478 clause 3): the nodes whose toolchains key reports the
+// version the nodes agree on, the ones with room under their build capacity first (places), then the fewest lanes the
+// part has running or chosen there, a tie broken by the node's name. A place is reserved on each node chosen, in the
+// same step as the choice, so builds choosing at once do not choose the same full node while another has room; the
+// caller takes the place (Places.Acquire) or gives it up (Places.Cancel). A node at its capacity is still chosen when
+// the others are too (fewer than want have room): its lane waits for a place. A node qualifies only when qualifies is true
+// of it (online and its build module healthy; nil means every node does). It answers the toolchain all the reporting nodes
+// agree on, qualifying or not, as the indexer computes it. When nothing is reported, or the nodes report different
+// versions (so the indexer agreed none), it fails naming the language and why; when no reporting node qualifies it fails
+// naming the nodes. A node whose build module refuses on its toolchain refuses the step, and the build fails naming it.
+func ChooseNodes(language string, entries []delivery.NodeToolchain, places *Places, qualifies func(node string) bool, want int) ([]string, delivery.Toolchain2, error) {
+	tc, none := delivery.AgreedToolchain(entries)
+	if none != "" {
+		return nil, delivery.Toolchain2{}, fmt.Errorf("no %s build node qualifies: %s", language, none)
+	}
+	nodes, err := choose(language, entries, places, qualifies, want)
+	return nodes, tc, err
+}
+
+// ChooseAnyNodes is ChooseNodes for artifacts that need no toolchain, such as an archive (ADR 0478 clause 1): the
+// build module's nodes agree on nothing, so any node of the build module that qualifies is chosen, by capacity and load only.
+func ChooseAnyNodes(language string, entries []delivery.NodeToolchain, places *Places, qualifies func(node string) bool, want int) ([]string, error) {
+	return choose(language, entries, places, qualifies, want)
+}
+
+func choose(language string, entries []delivery.NodeToolchain, places *Places, qualifies func(node string) bool, want int) ([]string, error) {
+	if places == nil {
+		places = &Places{}
+	}
+	nodes := make([]string, 0, len(entries))
+	var reporting []string
+	seen := map[string]bool{}
+	for _, e := range entries {
+		if seen[e.Node] {
+			continue
+		}
+		seen[e.Node] = true
+		reporting = append(reporting, e.Node)
+		if places.CapacityOf(e.Node) > 0 && (qualifies == nil || qualifies(e.Node)) { // a capacity of 0 keeps the part off a node
+			nodes = append(nodes, e.Node)
+		}
+	}
+	if len(nodes) == 0 {
+		sort.Strings(reporting)
+		return nil, fmt.Errorf("no %s build node qualifies: %s report the toolchain, and none is online with a healthy build module and a build capacity", language, strings.Join(reporting, ", "))
+	}
+	return places.choose(nodes, want), nil
+}
+
+// DigestsDifferPrefix opens the error of a build whose nodes built an artifact to different digests (ADR 0478 clause 4):
+// such a key is not built again as a new revision, since the same source on the same toolchains gave two answers and
+// building again settles nothing; it waits for another fingerprint.
+const DigestsDifferPrefix = "digests differ:"
+
+// Agree is the one digest every node built an artifact to (ADR 0478 clause 4), or an error naming each node and its
+// digest when they differ. One node's digest agrees with itself.
+func Agree(artifact string, byNode map[string]string) (string, error) {
+	nodes := make([]string, 0, len(byNode))
+	for n := range byNode {
+		nodes = append(nodes, n)
+	}
+	sort.Strings(nodes)
+	var first string
+	for i, n := range nodes {
+		if i == 0 {
+			first = byNode[n]
+			continue
+		}
+		if byNode[n] != first {
+			msg := fmt.Sprintf("%s the nodes built %s to different digests:", DigestsDifferPrefix, artifact)
+			for _, n := range nodes {
+				msg += fmt.Sprintf(" %s %s;", n, byNode[n])
+			}
+			return "", fmt.Errorf("%s", msg[:len(msg)-1])
+		}
+	}
+	return first, nil
+}

modules/mesh-delivery-builder/buildrun/choose_test.go

@@ -0,0 +1,109 @@
+package buildrun
+
+import (
+	"strings"
+	"testing"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+const digest = "sha256:2222222222222222222222222222222222222222222222222222222222222222"
+
+func hex64(c byte) string { return strings.Repeat(string(c), 64) }
+
+func tcs(language, version string, nodes ...string) []delivery.NodeToolchain {
+	var out []delivery.NodeToolchain
+	for _, n := range nodes {
+		out = append(out, delivery.NodeToolchain{Node: n, Toolchain: delivery.Toolchain{Language: language, Version: version, Recipe: "1"}})
+	}
+	return out
+}
+
+func chooseTakesTheAgreedNodesWithFewestRunningStepsTiesByName(t *testing.T) { // 1607/AC4, ADR 0478 clause 3
+	entries := tcs("go", "go1.27.1", "novox", "ace", "g14", "shanks")
+	nodes, tc, err := ChooseNodes("go", entries, placesRunning(map[string]int{"novox": 3, "ace": 1, "g14": 1, "shanks": 0}), nil, 2)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(nodes) != 2 || nodes[0] != "shanks" || nodes[1] != "ace" {
+		t.Errorf("nodes = %v, want [shanks ace]: fewest steps first, a tie by name", nodes)
+	}
+	if tc.Version != "go1.27.1" || tc.Recipe != "1" || tc.Language != "go" {
+		t.Errorf("toolchain = %+v", tc)
+	}
+}
+
+func chooseWithOneNodeAnswersOneNode(t *testing.T) { // 1607/AC4
+	nodes, _, err := ChooseNodes("go", tcs("go", "go1.27.1", "novox"), nil, nil, 2)
+	if err != nil || len(nodes) != 1 || nodes[0] != "novox" {
+		t.Errorf("nodes = %v, err %v, want [novox]", nodes, err)
+	}
+}
+
+func chooseFailsNamingTheLanguageAndTheVersionsWhenNoNodeQualifies(t *testing.T) { // 1607/AC4
+	_, _, err := ChooseNodes("typescript", nil, nil, nil, 2)
+	if err == nil || !strings.Contains(err.Error(), "typescript") || !strings.Contains(err.Error(), delivery.ToolchainNoReport) {
+		t.Errorf("no report: error = %v, want it to name typescript and %q", err, delivery.ToolchainNoReport)
+	}
+	entries := append(tcs("go", "go1.27.1", "novox"), tcs("go", "go1.26.0", "ace")...)
+	_, _, err = ChooseNodes("go", entries, nil, nil, 2)
+	if err == nil || !strings.Contains(err.Error(), "go1.27.1") || !strings.Contains(err.Error(), "go1.26.0") || !strings.Contains(err.Error(), "go") {
+		t.Errorf("disagreeing nodes: error = %v, want both versions named", err)
+	}
+}
+
+func agreeNeedsEqualDigestsAndNamesBothNodesWhenTheyDiffer(t *testing.T) { // 1607/AC4, ADR 0478 clause 4
+	d, err := Agree("tool", map[string]string{"ace": digest, "novox": digest})
+	if err != nil || d != digest {
+		t.Errorf("Agree = %q, %v, want %q", d, err, digest)
+	}
+	_, err = Agree("tool", map[string]string{"ace": digest, "novox": "sha256:" + hex64('9')})
+	if err == nil || !strings.Contains(err.Error(), "ace") || !strings.Contains(err.Error(), "novox") || !strings.Contains(err.Error(), digest) || !strings.Contains(err.Error(), hex64('9')) || !strings.Contains(err.Error(), "tool") {
+		t.Errorf("differing digests: error = %v, want the artifact, both nodes and both digests", err)
+	}
+	if d, err := Agree("tool", map[string]string{"ace": digest}); err != nil || d != digest {
+		t.Errorf("one node: %q, %v", d, err)
+	}
+}
+
+func chooseSkipsNodesThatAreNotOnlineAndFailsNamingThemWhenNoneIs(t *testing.T) { // 1607 review 3, ADR 0478 clause 3
+	entries := tcs("go", "go1.27.1", "ace", "g14", "novox")
+	online := func(n string) bool { return n != "g14" } // a sleeping laptop
+	nodes, tc, err := ChooseNodes("go", entries, placesRunning(map[string]int{"novox": 5}), online, 2)
+	if err != nil || len(nodes) != 2 || nodes[0] != "ace" || nodes[1] != "novox" || tc.Version != "go1.27.1" {
+		t.Errorf("nodes = %v, toolchain %+v, err %v, want [ace novox] with g14 left out although it runs nothing", nodes, tc, err)
+	}
+	_, tc, err = ChooseNodes("go", entries, nil, func(string) bool { return false }, 2)
+	if err == nil || !strings.Contains(err.Error(), "online") || !strings.Contains(err.Error(), "g14") || !strings.Contains(err.Error(), "go") {
+		t.Errorf("none online: error = %v, want it to name the nodes that report and that none is online", err)
+	}
+	if tc.Version != "go1.27.1" {
+		t.Errorf("none online: the agreed toolchain %+v is still answered", tc)
+	}
+}
+
+// placesRunning is Places with these steps counted as running, for a test of the choice.
+func placesRunning(running map[string]int) *Places {
+	return &Places{running: running, changed: make(chan struct{})}
+}
+
+func choosePrefersNodesBelowTheirCapacity(t *testing.T) { // round 3
+	entries := tcs("go", "go1.27.1", "ace", "novox", "shanks")
+	// shanks has capacity 3 with 2 running: room; ace has the default 1 with 1 running: none; novox has none running.
+	p := placesRunning(map[string]int{"shanks": 2, "ace": 1})
+	p.Capacity = map[string]int{"shanks": 3}
+	nodes, _, err := ChooseNodes("go", entries, p, nil, 2)
+	if err != nil || len(nodes) != 2 || nodes[0] != "novox" || nodes[1] != "shanks" {
+		t.Errorf("nodes = %v, err %v, want [novox shanks]: the nodes with room, ace at capacity left out", nodes, err)
+	}
+}
+
+// The choice of the nodes a step runs on and the agreement of their answers, one table of cases (the test budget).
+func TestChoosingTheNodesOfAStep(t *testing.T) {
+	t.Run("choose takes the agreed nodes with fewest running steps ties by name", chooseTakesTheAgreedNodesWithFewestRunningStepsTiesByName)
+	t.Run("choose with one node answers one node", chooseWithOneNodeAnswersOneNode)
+	t.Run("choose fails naming the language and the versions when no node qualifies", chooseFailsNamingTheLanguageAndTheVersionsWhenNoNodeQualifies)
+	t.Run("agree needs equal digests and names both nodes when they differ", agreeNeedsEqualDigestsAndNamesBothNodesWhenTheyDiffer)
+	t.Run("choose skips nodes that are not online and fails naming them when none is", chooseSkipsNodesThatAreNotOnlineAndFailsNamingThemWhenNoneIs)
+	t.Run("choose prefers nodes below their capacity", choosePrefersNodesBelowTheirCapacity)
+}

modules/mesh-delivery-builder/buildrun/doc.go

@@ -0,0 +1,5 @@
+// Package buildrun holds the parts every module that runs steps on the build modules shares: the caller, the steps
+// watch and the runner of a long step (ADR 0469), the sets of presence, toolchains and healthy build modules, the
+// places a node offers by capacity, and the choice of build nodes (ADR 0478). The builder and the checker of the
+// delivery use them; they moved here from the builder's own package so neither keeps a copy (issue 1671, ADR 0484).
+package buildrun

modules/mesh-delivery-builder/buildrun/go.mod

@@ -0,0 +1,23 @@
+module git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun
+
+go 1.26.0
+
+require (
+	git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261104174359-05b3e2e1b94f
+	github.com/nats-io/nats.go v1.54.0
+)
+
+require (
+	git.novox.be/novox/mesh-contracts/go v0.0.0-20261104174344-ae5266e77639 // indirect
+	github.com/antithesishq/antithesis-sdk-go v0.8.0-default-no-op // indirect
+	github.com/google/go-tpm v0.9.8 // indirect
+	github.com/klauspost/compress v1.20.1 // indirect
+	github.com/minio/highwayhash v1.0.4 // indirect
+	github.com/nats-io/jwt/v2 v2.8.2 // indirect
+	github.com/nats-io/nats-server/v2 v2.11.17 // indirect
+	github.com/nats-io/nkeys v0.4.16 // indirect
+	github.com/nats-io/nuid v1.0.1 // indirect
+	golang.org/x/crypto v0.57.0 // indirect
+	golang.org/x/sys v0.48.0 // indirect
+	golang.org/x/time v0.16.0 // indirect
+)

modules/mesh-delivery-builder/buildrun/go.sum

@@ -0,0 +1,29 @@
+git.novox.be/novox/mesh-contracts/go v0.0.0-20261104174344-ae5266e77639 h1:Zt7CfWt2S2W/fVgWNyW2u2+xwz051LXvGxVTNIyfhdM=
+git.novox.be/novox/mesh-contracts/go v0.0.0-20261104174344-ae5266e77639/go.mod h1:0dD1XEJBJ0G5UYDQxSZI84nuujb6m3tOpJl4C8rQVvg=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261104174359-05b3e2e1b94f h1:jDsfDMd48MXY9Zershc3eRxnhmx2sSpUfQkLq5jAIds=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261104174359-05b3e2e1b94f/go.mod h1:08OomDXdwVN8/87nyDtv5R3rH/6LoP8SFFXz30bTYCM=
+github.com/antithesishq/antithesis-sdk-go v0.8.0-default-no-op h1:1BOWQJweNyvZMlpAHXGLiZQn9S+QXGcz3xh94lC0w6E=
+github.com/antithesishq/antithesis-sdk-go v0.8.0-default-no-op/go.mod h1:FQyySiasQQM8735Ddel3MRojmy4dA1IqCeyJ5jmPMbI=
+github.com/google/go-tpm v0.9.8 h1:slArAR9Ft+1ybZu0lBwpSmpwhRXaa85hWtMinMyRAWo=
+github.com/google/go-tpm v0.9.8/go.mod h1:h9jEsEECg7gtLis0upRBQU+GhYVH6jMjrFxI8u6bVUY=
+github.com/klauspost/compress v1.20.1 h1:T7kKElXUMXrUJ2E9QhQhxFtcK5rPyLdsGZvdbLMPdiQ=
+github.com/klauspost/compress v1.20.1/go.mod h1:LUdAzn7YLVvxLpc7y3V1m40wESHTgc1422pwwBSKYuI=
+github.com/minio/highwayhash v1.0.4 h1:asJizugGgchQod2ja9NJlGOWq4s7KsAWr5XUc9Clgl4=
+github.com/minio/highwayhash v1.0.4/go.mod h1:GGYsuwP/fPD6Y9hMiXuapVvlIUEhFhMTh0rxU3ik1LQ=
+github.com/nats-io/jwt/v2 v2.8.2 h1:XXRgB60MSTnqsRwejQurVDs/hcv2dkt+86GjI+I/bMc=
+github.com/nats-io/jwt/v2 v2.8.2/go.mod h1:Ag/56sq9OblL4JgdYufDd16Egb17Kr/8WwwuO/forVc=
+github.com/nats-io/nats-server/v2 v2.11.17 h1:GKEghcFK6A+aFx11Yf1LjgLC3txAwvyhnYzhBIQZA8I=
+github.com/nats-io/nats-server/v2 v2.11.17/go.mod h1:B1sFVz4StNosQ903ak4N1G01Fl/9f8e06mXpFIE2K24=
+github.com/nats-io/nats.go v1.54.0 h1:vsXoOxjHp/GmPUN+EcI7uOf/uB+iAP+kEsAFNQN0yzA=
+github.com/nats-io/nats.go v1.54.0/go.mod h1:y+DZoD1oBOYfZTU681eTUiUjI0vbqYGixNVFHcjHJ0k=
+github.com/nats-io/nkeys v0.4.16 h1:rd5oAuLOb8mnAycB0xleuEBNS1pVVnN0fv/FF34Eypg=
+github.com/nats-io/nkeys v0.4.16/go.mod h1:llLgWoI0o4z/Q57q2R1kHfmocyhGV6VG/U18Glg1Afs=
+github.com/nats-io/nuid v1.0.1 h1:5iA8DT8V7q8WK2EScv2padNa/rTESc1KdnPw4TC2paw=
+github.com/nats-io/nuid v1.0.1/go.mod h1:19wcPz3Ph3q0Jbyiqsd0kePYG7A95tJPxeL+1OSON2c=
+golang.org/x/crypto v0.57.0 h1:3ZVCjf8Ggz7zneR/EHRVx68Ctf+2pmIMP2UFhh9cC6M=
+golang.org/x/crypto v0.57.0/go.mod h1:Fdz0i5U6CoizGwLda9DttjSk6qlZo25zYNtR+ycvuZA=
+golang.org/x/sys v0.21.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/sys v0.48.0 h1:bbX/i/6MgT9BVLM9RT1thmxL04yeTAhbEz4SyadbXoo=
+golang.org/x/sys v0.48.0/go.mod h1:hNLxWAXmnKAxqDtdwIYC4bM9oQPEecfsnNMuSxOs3og=
+golang.org/x/time v0.16.0 h1:vMb6ptszcQMkcwiRTAuNNU50gom6++Q/6gY2hDM6VDE=
+golang.org/x/time v0.16.0/go.mod h1:rVKOqvZeKvrDKTQiAHJ7wmwP0RzleSphoEA9RcdLA0s=

modules/mesh-delivery-builder/buildrun/have.go

@@ -0,0 +1,56 @@
+package buildrun
+
+import (
+	"sync"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// HaveSet holds what each node's node-engine says of each module on it (node-engine_have, key `<node>.<module>`): the
+// builder reads it to know whether a node's build module is running and healthy, since a build module whose installed
+// toolchain is not the one its recipe builds with is unhealthy (mesh-build-go build_go_health) and its steps would
+// refuse (ADR 0478 clause 3). A module the node-engine has written no key of is not healthy. Safe for use from the watch
+// and from a build at once.
+type HaveSet struct {
+	mu      sync.Mutex
+	healthy map[string]bool // by `<node>.<module>`
+}
+
+// Put takes a change of the have bucket in and answers whether a module's healthy state changed. A node's own key
+// (`<node>.node`) and a value that is not a have are left out.
+func (s *HaveSet) Put(key string, value []byte, deleted bool) bool {
+	node, module, isNode, err := delivery.ParseHaveKey(key)
+	if err != nil || isNode {
+		return false
+	}
+	ok := false
+	if !deleted {
+		h, err := delivery.DecodeHave(value)
+		if err != nil {
+			return false
+		}
+		ok = h.Phase == delivery.PhaseRunning && h.Health == delivery.HealthOK
+	}
+	k := node + "." + module
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if s.healthy[k] == ok {
+		return false
+	}
+	if s.healthy == nil {
+		s.healthy = map[string]bool{}
+	}
+	if ok {
+		s.healthy[k] = true
+	} else {
+		delete(s.healthy, k)
+	}
+	return true
+}
+
+// Healthy is whether the module on the node was last seen running and healthy.
+func (s *HaveSet) Healthy(node, module string) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.healthy[node+"."+module]
+}

modules/mesh-delivery-builder/buildrun/heardends.go

@@ -0,0 +1,236 @@
+package buildrun
+
+import (
+	"context"
+	"fmt"
+	"sync"
+
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// **A step's end is never only its own watch's to hear** (the lost check of 2026-10-28: mesh-catalog #553's verdict
+// stayed running after its step mvsgthyjed5786 had passed on shanks at 19:09:31Z; the watch of that one key, opened at
+// 18:46:05Z, heard neither the step's start nor its end and never closed, while a watch opened at 18:58:48Z heard its own
+// step end). HeardEnds stands between the asker (Asker) and the watch of each ask's step key: when it is
+// nudged, every ask it waits on reads its step keys now (a read, not the watch) and hands what it reads to its wait, so a
+// step that ended is judged even when its own watch went deaf. A watch that closes under a wait is opened again, at most
+// reopenTries times. It is nudged on an event (Nudge): any step of the same build module ending (one watch of each steps
+// state, HearEnds), a reconnect to the bus, and whatever else the asker hears (the checker: checker_ask_again).
+// It holds no timer. Every asker of the build seats waits through it (the checker and the builder, HearEnds).
+
+// StepReader reads, now, every step a build module's steps state holds for an ask: its keys `*.<ask id>`.
+type StepReader interface {
+	AskSteps(ctx context.Context, module, askID string) ([]delivery.Step, error)
+}
+
+// reopenTries is how often a wait opens its ask's watch again after it closed, before the wait ends failed.
+const reopenTries = 3
+
+// HeardEnds is an AskWaiter over Inner that also reads an ask's steps when nudged. Safe for concurrent use.
+type HeardEnds struct {
+	Inner AskWaiter
+	Read  StepReader
+	Logf  func(format string, args ...any)
+
+	mu      sync.Mutex
+	waiting map[string]*waitedAsk // by ask id
+}
+
+type waitedAsk struct {
+	module string
+	nudge  chan struct{}
+}
+
+func (h *HeardEnds) logf(format string, args ...any) {
+	if h.Logf != nil {
+		h.Logf(format, args...)
+	}
+}
+
+// WatchAsk is AskWaiter's: what Inner's watch hands, and, at each nudge, what the ask's keys hold now.
+func (h *HeardEnds) WatchAsk(ctx context.Context, module, askID string) (<-chan delivery.Step, error) {
+	in, err := h.Inner.WatchAsk(ctx, module, askID)
+	if err != nil {
+		return nil, err
+	}
+	w := &waitedAsk{module: module, nudge: make(chan struct{}, 1)}
+	h.mu.Lock()
+	if h.waiting == nil {
+		h.waiting = map[string]*waitedAsk{}
+	}
+	h.waiting[askID] = w
+	h.mu.Unlock()
+	out := make(chan delivery.Step)
+	go func() {
+		defer close(out)
+		defer func() {
+			h.mu.Lock()
+			if h.waiting[askID] == w {
+				delete(h.waiting, askID)
+			}
+			h.mu.Unlock()
+		}()
+		send := func(s delivery.Step) bool {
+			select {
+			case out <- s:
+				return true
+			case <-ctx.Done():
+				return false
+			}
+		}
+		reopened := 0
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			case s, ok := <-in:
+				if !ok {
+					if ctx.Err() != nil || reopened >= reopenTries {
+						h.logf("the watch of the ask %s's step on %s closed %d times; its wait ends", askID, module, reopened+1)
+						return
+					}
+					reopened++
+					if in, err = h.Inner.WatchAsk(ctx, module, askID); err != nil {
+						h.logf("the watch of the ask %s's step on %s closed and cannot be opened again, so its wait ends: %v", askID, module, err)
+						return
+					}
+					h.logf("the watch of the ask %s's step on %s closed; opened again (%d of %d)", askID, module, reopened, reopenTries)
+					continue
+				}
+				if !send(s) {
+					return
+				}
+			case <-w.nudge:
+				if h.Read == nil {
+					continue
+				}
+				steps, err := h.Read.AskSteps(ctx, module, askID)
+				if err != nil {
+					h.logf("the steps of the ask %s on %s cannot be read: %v", askID, module, err)
+					continue
+				}
+				for _, s := range steps {
+					if s.State != delivery.StepRunning {
+						h.logf("the ask %s's step on %s ended %s, read at a nudge: its watch had not handed it over", askID, s.Node, s.State)
+					}
+					if !send(s) {
+						return
+					}
+				}
+			}
+		}
+	}()
+	return out, nil
+}
+
+// Nudge has every ask waited on of module read its steps now; module "" nudges every ask.
+func (h *HeardEnds) Nudge(module string) {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	for _, w := range h.waiting {
+		if module == "" || w.module == module {
+			select {
+			case w.nudge <- struct{}{}:
+			default: // a nudge is pending already
+			}
+		}
+	}
+}
+
+// Waiting is how many asks are waited on now.
+func (h *HeardEnds) Waiting() int {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	return len(h.waiting)
+}
+
+// AskSteps is StepReader's: the keys `*.<ask id>` of the build module's steps state, read now.
+func (s JetStreamAsks) AskSteps(ctx context.Context, module, askID string) ([]delivery.Step, error) {
+	pattern, err := delivery.AskStepWatch(askID)
+	if err != nil {
+		return nil, err
+	}
+	kv, err := s.JS.KeyValue(ctx, delivery.StepsBucket(module))
+	if err != nil {
+		return nil, fmt.Errorf("the bucket %s: %w", delivery.StepsBucket(module), err)
+	}
+	lister, err := kv.ListKeysFiltered(ctx, pattern)
+	if err != nil {
+		return nil, err
+	}
+	var out []delivery.Step
+	for key := range lister.Keys() {
+		e, err := kv.Get(ctx, key)
+		if err != nil {
+			continue // deleted between the list and the read
+		}
+		if step, err := delivery.DecodeStep(e.Value()); err == nil {
+			out = append(out, step)
+		}
+	}
+	return out, nil
+}
+
+// HearEnds is the HeardEnds every asker of the build seats waits through: over inner (the asks' own watches, or a
+// LostAskWaiter's inner), reading with asks, and nudged at each step end of each of modules (one watch of each steps state,
+// updates only; one that closes is opened again, and said and left after reopenTries closes in a row that heard nothing). The asker nudges it at a reconnect too (Nudge("")).
+func HearEnds(ctx context.Context, asks JetStreamAsks, inner AskWaiter, modules []string, logf func(string, ...any)) *HeardEnds {
+	if logf == nil {
+		logf = func(string, ...any) {}
+	}
+	h := &HeardEnds{Inner: inner, Read: asks, Logf: logf}
+	for _, module := range modules {
+		kv, err := asks.JS.KeyValue(ctx, delivery.StepsBucket(module))
+		if err != nil {
+			logf("the steps of %s cannot be read (%v): an ask whose own watch goes deaf is read only at a reconnect", module, err)
+			continue
+		}
+		go h.follow(ctx, kv, module)
+	}
+	return h
+}
+
+func (h *HeardEnds) follow(ctx context.Context, kv jetstream.KeyValue, module string) {
+	silent := 0 // closes in a row having heard nothing
+	for ctx.Err() == nil {
+		w, err := kv.WatchAll(ctx, jetstream.UpdatesOnly())
+		if err != nil {
+			h.logf("the steps of %s cannot be watched, so an ask whose own watch goes deaf is read only at a reconnect: %v", module, err)
+			return
+		}
+		heard := false
+		for e := range w.Updates() {
+			if e == nil || e.Operation() != jetstream.KeyValuePut {
+				continue
+			}
+			heard = true
+			if step, err := delivery.DecodeStep(e.Value()); err == nil && step.State != delivery.StepRunning {
+				h.Nudge(module)
+			}
+		}
+		_ = w.Stop()
+		if ctx.Err() != nil {
+			return
+		}
+		h.Nudge(module) // a step may have ended while the watch was closing
+		if heard {
+			silent = 0
+		} else if silent++; silent >= reopenTries {
+			h.logf("the watch of the steps of %s closed %d times in a row having heard nothing, so it is left: an ask whose own watch goes deaf is read only at a reconnect", module, silent)
+			return
+		}
+		h.logf("the watch of the steps of %s closed; opened again", module)
+	}
+}
+
+// AskSteps is StepReader's: the last step written for the ask, if any.
+func (f *FakeAsks) AskSteps(_ context.Context, _ string, askID string) ([]delivery.Step, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if s := f.steps[askID]; len(s) > 0 {
+		return []delivery.Step{s[len(s)-1]}, nil
+	}
+	return nil, nil
+}

modules/mesh-delivery-builder/buildrun/lostask.go

@@ -0,0 +1,503 @@
+package buildrun
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/health"
+	"git.novox.be/novox/mesh-sdk/go/process"
+)
+
+// **An ask the build seat gave up on ends its step** (novox/hq issue 734). A build seat's worker offers an ask
+// delivery.AskMaxDeliver times; one handed out that often without an answer (a bus reload that drops every hand-out, a node
+// that dies taking it each time) is given up by the server, and the controller keeps a copy of it in DEAD_LETTERS under
+// mesh.events.dead.<seat stream>.<worker>, with the ask's message id (its ask id), how often it was handed out and when it
+// was given up. No build node writes a step for it, so an asker that waits for the step waits for ever: a try stays
+// running and holds a try place, a check's verdict stays running and its pull request waits.
+//
+// An asker of the build seats (the checker, the builder) hears those copies (DeadLetterHearing: an ordered consumer on
+// DEAD_LETTERS filtered to the build seats' streams, granted to a user of a seat pulled by kind, buscompose
+// DeadLetterReads) into DeadLetters, and LostAskWaiter ends the waiting step at once as failed on the node LostNode, its
+// reason saying LostWords; the asker decides what follows (the checker ends a try as error and asks a check again, the
+// builder asks its part of a build again).
+//
+// Belt and braces, where the asker says so in the context (NotTakenBound; the checker's tries): an ask no build node took
+// within a bound ends the same way, saying NotTakenWords. An ask waits in the stream as long as the backlog is otherwise
+// (ADR 0525 §9): a backlog is no fault.
+
+// LostNode is the node a step ended for a lost ask names: no build node wrote it.
+const LostNode = "bus"
+
+// The words of a step ended for its ask.
+const (
+	LostWords     = "its ask was given up by the build seat"
+	NotTakenWords = "no build node took its ask"
+)
+
+// The headers the controller keeps a given-up message's copy with in DEAD_LETTERS (mesh-controller internal/link
+// deadletters.go): the original message id (an ask's is its ask id), how often it was handed out, when it was given up.
+const (
+	DeadHeaderMsgID      = "Mesh-Dead-Msg-Id"
+	DeadHeaderDeliveries = "Mesh-Dead-Deliveries"
+	DeadHeaderGaveUp     = "Mesh-Dead-Gave-Up"
+	DeadHeaderStream     = "Mesh-Dead-Stream"
+)
+
+// DeadLettersStream is the stream the controller keeps given-up messages in, and DeadLetterFilter the subjects of one seat
+// stream's copies there (buscompose DeadLetterSubject).
+const DeadLettersStream = "DEAD_LETTERS"
+
+// DeadLetterFilter is the subjects DEAD_LETTERS keeps a seat stream's given-up messages under.
+func DeadLetterFilter(stream string) string { return "mesh.events.dead." + stream + ".>" }
+
+// SeatStream is the stream of a build seat's language (buscompose seatStreamName of node-build-<language>).
+func SeatStream(language string) string { return "SEAT_NODE_BUILD_" + strings.ToUpper(language) }
+
+// GivenUp is one ask a build seat gave up on, as DEAD_LETTERS keeps it.
+type GivenUp struct {
+	AskID      string
+	Stream     string
+	Deliveries int
+	At         time.Time
+}
+
+// GivenUpOf reads a DEAD_LETTERS copy's headers; false when it names no message id.
+func GivenUpOf(header map[string][]string) (GivenUp, bool) {
+	get := func(k string) string {
+		if v := header[k]; len(v) > 0 {
+			return strings.TrimSpace(v[0])
+		}
+		return ""
+	}
+	g := GivenUp{AskID: get(DeadHeaderMsgID), Stream: get(DeadHeaderStream)}
+	if g.AskID == "" {
+		return GivenUp{}, false
+	}
+	g.Deliveries, _ = strconv.Atoi(get(DeadHeaderDeliveries))
+	g.At, _ = time.Parse(time.RFC3339Nano, get(DeadHeaderGaveUp))
+	return g, true
+}
+
+// Words are what a step ended for the given-up ask says.
+func (g GivenUp) Words() string {
+	at := "at an unknown time"
+	if !g.At.IsZero() {
+		at = "at " + g.At.UTC().Format(time.RFC3339)
+	}
+	return fmt.Sprintf("%s after %d deliveries %s (kept in %s); ask again", LostWords, g.Deliveries, at, DeadLettersStream)
+}
+
+// keptGivenUp is how many given-up asks DeadLetters remembers for a waiter that starts after the copy was heard.
+const keptGivenUp = 1024
+
+// DeadLetters holds the given-up asks heard, and hands each to the waiter of its ask. Safe for concurrent use.
+type DeadLetters struct {
+	mu       sync.Mutex
+	heard    map[string]GivenUp
+	order    []string
+	watchers map[string][]chan GivenUp
+}
+
+// Heard takes one given-up ask in.
+func (d *DeadLetters) Heard(g GivenUp) {
+	d.mu.Lock()
+	if d.heard == nil {
+		d.heard, d.watchers = map[string]GivenUp{}, map[string][]chan GivenUp{}
+	}
+	if _, ok := d.heard[g.AskID]; !ok {
+		d.order = append(d.order, g.AskID)
+		if len(d.order) > keptGivenUp {
+			delete(d.heard, d.order[0])
+			d.order = d.order[1:]
+		}
+	}
+	d.heard[g.AskID] = g
+	ws := d.watchers[g.AskID]
+	delete(d.watchers, g.AskID)
+	d.mu.Unlock()
+	for _, w := range ws {
+		w <- g // buffered, one each
+	}
+}
+
+// watch answers a channel that gets the ask's given-up copy once (at once when it was heard already), and its cancel.
+func (d *DeadLetters) watch(askID string) (<-chan GivenUp, func()) {
+	ch := make(chan GivenUp, 1)
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	if d.heard == nil {
+		d.heard, d.watchers = map[string]GivenUp{}, map[string][]chan GivenUp{}
+	}
+	if g, ok := d.heard[askID]; ok {
+		ch <- g
+		return ch, func() {}
+	}
+	d.watchers[askID] = append(d.watchers[askID], ch)
+	return ch, func() {
+		d.mu.Lock()
+		defer d.mu.Unlock()
+		ws := d.watchers[askID]
+		for i, w := range ws {
+			if w == ch {
+				d.watchers[askID] = append(ws[:i], ws[i+1:]...)
+				break
+			}
+		}
+		if len(d.watchers[askID]) == 0 {
+			delete(d.watchers, askID)
+		}
+	}
+}
+
+type notTakenKey struct{}
+
+// NotTakenBound says, in ctx, that an ask no build node took within bound ends its step (a try's, never a check's).
+func NotTakenBound(ctx context.Context, bound time.Duration) context.Context {
+	return context.WithValue(ctx, notTakenKey{}, bound)
+}
+
+func notTakenBoundOf(ctx context.Context) time.Duration {
+	d, _ := ctx.Value(notTakenKey{}).(time.Duration)
+	return d
+}
+
+// LostAskWaiter is an AskWaiter that ends an ask's step when the build seat gave the ask up (DeadLetters), or, under
+// NotTakenBound, when no build node took it within the bound: it hands the asker a failed step whose reason says why, on
+// the node "bus". Every step the build module writes is handed on as it is.
+type LostAskWaiter struct {
+	Inner AskWaiter
+	Dead  *DeadLetters
+	// Hearing, when set, is asked to hear DEAD_LETTERS again each time an ask is waited for while it cannot: an ask put is
+	// the event that makes hearing matter.
+	Hearing interface {
+		Deaf() string
+		Again()
+	}
+	Now func() time.Time
+}
+
+func (w LostAskWaiter) now() time.Time {
+	if w.Now != nil {
+		return w.Now()
+	}
+	return time.Now()
+}
+
+// WatchAsk is AskWaiter's.
+func (w LostAskWaiter) WatchAsk(ctx context.Context, module, askID string) (<-chan delivery.Step, error) {
+	if w.Hearing != nil && w.Hearing.Deaf() != "" {
+		w.Hearing.Again()
+	}
+	inner, err := w.Inner.WatchAsk(ctx, module, askID)
+	if err != nil {
+		return nil, err
+	}
+	var dead <-chan GivenUp
+	cancel := func() {}
+	if w.Dead != nil {
+		dead, cancel = w.Dead.watch(askID)
+	}
+	// The not-taken bound is a context's (ADR 0437 §8: no timer), ended when a node takes the ask.
+	var notTaken <-chan struct{}
+	bound := notTakenBoundOf(ctx)
+	stopBound := func() {}
+	if bound > 0 {
+		var nt context.Context
+		nt, stopBound = context.WithTimeout(context.Background(), bound)
+		notTaken = nt.Done()
+	}
+	out := make(chan delivery.Step)
+	go func() {
+		defer close(out)
+		defer cancel()
+		defer func() { stopBound() }()
+		send := func(s delivery.Step) bool {
+			select {
+			case out <- s:
+				return true
+			case <-ctx.Done():
+				return false
+			}
+		}
+		ended := func(reason string) delivery.Step {
+			at := w.now().UTC()
+			return delivery.Step{ID: askID, Node: LostNode, State: delivery.StepFailed, Reason: reason, Ended: at}
+		}
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			case s, ok := <-inner:
+				if !ok {
+					return
+				}
+				if notTaken != nil {
+					stopBound() // a node took it: its step is bounded by the asker from its start
+					notTaken = nil
+				}
+				if !send(s) {
+					return
+				}
+			case g := <-dead:
+				dead = nil
+				send(ended(g.Words()))
+				return
+			case <-notTaken:
+				send(ended(fmt.Sprintf("%s within %s of its put; it was lost or waits behind a backlog; ask again", NotTakenWords, bound)))
+				return
+			}
+		}
+	}()
+	return out, nil
+}
+
+// IsLost says whether a step was ended by LostAskWaiter because the build seat gave its ask up (LostWords).
+func IsLost(s delivery.Step) bool { return s.Node == LostNode && strings.Contains(s.Reason, LostWords) }
+
+// IsNotTaken says whether a step was ended by LostAskWaiter because no build node took its ask within the bound.
+func IsNotTaken(s delivery.Step) bool {
+	return s.Node == LostNode && strings.Contains(s.Reason, NotTakenWords)
+}
+
+// **The asker hears DEAD_LETTERS, tries again when it cannot, and says whether it hears** (issue 734). The read is
+// granted with the asker's seat traffic (buscompose DeadLetterReads); an asker started before its grant was composed is
+// refused, and an asker that only tried once would stay deaf until it starts again, silently. DeadLetterHearing tries in
+// the background, never holding the start up, and again on an event (Again): the asker's reconnect to the bus, and every
+// ask waited for while it is deaf (LostAskWaiter.Hearing); no timer. Each change of whether it hears is said (Said), so
+// the module's health tool says it: a deaf asker is not healthy.
+
+// Hearing is what a DeadLetterHearing says: whether it hears every build seat stream it follows, and why not.
+type Hearing struct {
+	Heard   bool      `json:"heard"`
+	Streams []string  `json:"streams"`
+	Why     string    `json:"why,omitempty"`
+	At      time.Time `json:"at"`
+}
+
+// HearingKey is the key a module keeps its Hearing under, in its own state (the checker's and the builder's hearing).
+const HearingKey = "dead-letters"
+
+// DeadLetterFollower starts following one seat stream's copies in DEAD_LETTERS from since, handing each given-up ask to
+// heard; it answers the stop, or why it cannot.
+type DeadLetterFollower interface {
+	Follow(ctx context.Context, stream string, since time.Time, heard func(GivenUp)) (func(), error)
+}
+
+// JetStreamDeadLetters is the bus side of a DeadLetterFollower: an ordered consumer on DEAD_LETTERS filtered to the
+// stream's copies, which resumes where it was after a reconnect and, reset before it heard any, starts at since again.
+type JetStreamDeadLetters struct{ JS jetstream.JetStream }
+
+// Follow is DeadLetterFollower's.
+func (j JetStreamDeadLetters) Follow(ctx context.Context, stream string, since time.Time, heard func(GivenUp)) (func(), error) {
+	cons, err := j.JS.OrderedConsumer(ctx, DeadLettersStream, jetstream.OrderedConsumerConfig{
+		FilterSubjects: []string{DeadLetterFilter(stream)}, DeliverPolicy: jetstream.DeliverByStartTimePolicy, OptStartTime: &since})
+	if err != nil {
+		return nil, err
+	}
+	cc, err := cons.Consume(func(m jetstream.Msg) {
+		if g, ok := GivenUpOf(m.Headers()); ok {
+			heard(g)
+		}
+	})
+	if err != nil {
+		return nil, err
+	}
+	return cc.Stop, nil
+}
+
+// DeadLetterHearing follows the build seats' given-up asks into Dead. Make it with NewDeadLetterHearing.
+type DeadLetterHearing struct {
+	follower DeadLetterFollower
+	streams  []string
+	dead     *DeadLetters
+	logf     func(string, ...any)
+	said     func(Hearing)
+	ctx      context.Context
+	since    time.Time
+
+	mu     sync.Mutex
+	stops  map[string]func()
+	why    map[string]string
+	trying bool
+	again  bool
+	told   *Hearing
+	wg     sync.WaitGroup
+}
+
+// NewDeadLetterHearing starts hearing the given-up asks of each language's build seat stream, in the background. said
+// is told each change of whether it hears (nil tells nothing); ctx ends it.
+func NewDeadLetterHearing(ctx context.Context, follower DeadLetterFollower, languages []string, dead *DeadLetters,
+	logf func(string, ...any), said func(Hearing)) *DeadLetterHearing {
+	h := &DeadLetterHearing{follower: follower, dead: dead, logf: logf, said: said, ctx: ctx, since: time.Now(),
+		stops: map[string]func(){}, why: map[string]string{}}
+	for _, l := range languages {
+		s := SeatStream(l)
+		h.streams = append(h.streams, s)
+		h.why[s] = "not tried yet"
+	}
+	if h.logf == nil {
+		h.logf = func(string, ...any) {}
+	}
+	h.Again()
+	return h
+}
+
+// Deaf says why a stream is not heard, or "" when every one is.
+func (h *DeadLetterHearing) Deaf() string {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	return h.deafLocked()
+}
+
+func (h *DeadLetterHearing) deafLocked() string {
+	var out []string
+	for _, s := range h.streams {
+		if why, deaf := h.why[s]; deaf {
+			out = append(out, s+": "+why)
+		}
+	}
+	if len(out) == 0 {
+		return ""
+	}
+	return DeadLettersStream + " is not heard, so an ask a build seat gives up on is waited for until its bound: " +
+		strings.Join(out, "; ")
+}
+
+// Again tries, in the background, every stream not heard yet; a call while it tries makes it try once more after.
+func (h *DeadLetterHearing) Again() {
+	h.mu.Lock()
+	if h.trying {
+		h.again = true
+		h.mu.Unlock()
+		return
+	}
+	h.trying = true
+	h.mu.Unlock()
+	h.wg.Add(1)
+	go func() {
+		defer h.wg.Done()
+		for {
+			h.try()
+			h.mu.Lock()
+			if !h.again || h.ctx.Err() != nil {
+				h.trying = false
+				h.mu.Unlock()
+				return
+			}
+			h.again = false
+			h.mu.Unlock()
+		}
+	}()
+}
+
+// Wait returns when no try runs.
+func (h *DeadLetterHearing) Wait() { h.wg.Wait() }
+
+// Stop ends every stream's following.
+func (h *DeadLetterHearing) Stop() {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	for s, stop := range h.stops {
+		stop()
+		delete(h.stops, s)
+	}
+}
+
+func (h *DeadLetterHearing) try() {
+	for _, s := range h.streams {
+		h.mu.Lock()
+		_, deaf := h.why[s]
+		h.mu.Unlock()
+		if !deaf || h.ctx.Err() != nil {
+			continue
+		}
+		stream := s
+		stop, err := h.follower.Follow(h.ctx, stream, h.since, func(g GivenUp) {
+			h.logf("the ask %s on %s was given up after %d deliveries at %s: the wait for its step ends", g.AskID, g.Stream,
+				g.Deliveries, g.At.Format(time.RFC3339))
+			h.dead.Heard(g)
+		})
+		h.mu.Lock()
+		if err != nil {
+			h.why[stream] = err.Error()
+			h.logf("the asks %s gives up on are not heard (%s of %s); tried again at the next reconnect or ask: %v",
+				stream, DeadLetterFilter(stream), DeadLettersStream, err)
+		} else {
+			delete(h.why, stream)
+			h.stops[stream] = stop
+			h.logf("the asks %s gives up on are heard from %s", stream, DeadLettersStream)
+		}
+		h.mu.Unlock()
+	}
+	h.tell()
+}
+
+// tell says the hearing when it changed.
+func (h *DeadLetterHearing) tell() {
+	h.mu.Lock()
+	why := h.deafLocked()
+	now := Hearing{Heard: why == "", Streams: append([]string(nil), h.streams...), Why: why, At: time.Now().UTC()}
+	same := h.told != nil && h.told.Heard == now.Heard && h.told.Why == now.Why
+	if !same {
+		h.told = &now
+	}
+	h.mu.Unlock()
+	if !same && h.said != nil {
+		h.said(now)
+	}
+}
+
+// HearingState is the name of the state an asker keeps its Hearing in (`<module>_hearing`, key HearingKey), which its
+// health tool reads.
+const HearingState = "hearing"
+
+// HearingKeeper is where a Hearing is kept: a jetstream.KeyValue, or a process.AwaitedBucket for a state that may not be
+// on the bus at the part's start (issue 1790), which keeps the latest until it appears and answers process.ErrNotYet.
+type HearingKeeper interface {
+	Put(ctx context.Context, key string, value []byte) (uint64, error)
+}
+
+// SayHearing is a DeadLetterHearing's said that keeps each Hearing in kv under HearingKey; nil kv keeps nothing and
+// says so once. A write kv keeps for later (process.ErrNotYet) is not an error: the awaited bucket said it waits.
+func SayHearing(ctx context.Context, kv HearingKeeper, logf func(string, ...any)) func(Hearing) {
+	if kv == nil {
+		if logf != nil {
+			logf("whether %s is heard is not kept: the state %s is not there, so the health tool cannot say it", DeadLettersStream, HearingState)
+		}
+		return nil
+	}
+	return func(h Hearing) {
+		data, err := json.Marshal(h)
+		if err == nil {
+			_, err = kv.Put(ctx, HearingKey, data)
+		}
+		if err != nil && !errors.Is(err, process.ErrNotYet) && logf != nil {
+			logf("whether %s is heard could not be kept: %v", DeadLettersStream, err)
+		}
+	}
+}
+
+// HearingHealth is the health answer of an asker's kept Hearing (raw, empty when none is kept): healthy while it hears
+// DEAD_LETTERS, unhealthy saying why while it does not or has not said.
+func HearingHealth(raw []byte) health.Answer {
+	if len(raw) == 0 {
+		return health.Unhealthy("it has not said whether it hears " + DeadLettersStream + " (issue 734): it is starting, or its state " + HearingState + " is not there")
+	}
+	var h Hearing
+	if err := json.Unmarshal(raw, &h); err != nil {
+		return health.Unhealthy("what it keeps of hearing " + DeadLettersStream + " is not a hearing: " + err.Error())
+	}
+	if !h.Heard {
+		return health.Unhealthy(h.Why + " (since " + h.At.Format(time.RFC3339) + "; tried again at its next reconnect or ask)")
+	}
+	return health.Healthy("it hears " + DeadLettersStream + " for " + strings.Join(h.Streams, ", "))
+}

modules/mesh-delivery-builder/buildrun/modules.go

@@ -0,0 +1,7 @@
+package buildrun
+
+// The build modules the mesh runs, by the language each builds (ADR 0469).
+const (
+	GoBuildModule   = "mesh-build-go"
+	NodeBuildModule = "mesh-build-node"
+)

modules/mesh-delivery-builder/buildrun/places.go

@@ -0,0 +1,145 @@
+package buildrun
+
+import (
+	"context"
+	"fmt"
+	"sort"
+	"sync"
+)
+
+// DefaultCapacity is the build capacity of a node that has no setting: one build step at a time.
+const DefaultCapacity = 1
+
+// Places counts the build steps a part runs on each node and holds a lane back while its node is at its
+// capacity (the operator's decision of 2026-10-21; ADR 0478 clause 3). A lane is the fetch and the builds of one build
+// module on one node, run one step at a time, so a lane holds one place while it runs. A node is chosen for a lane by
+// reserving a place on it at the moment of the choice (ChooseNodes), so that builds choosing at once see each other's
+// choices and none waits on a full node while another has room. A lane waits for its place by watching the ends of the
+// other lanes, not by a timer: ending a lane wakes the waiting ones.
+type Places struct {
+	// Capacity is the number of steps at once by node; a node not in it has DefaultCapacity.
+	Capacity map[string]int
+
+	mu       sync.Mutex
+	running  map[string]int // lanes holding a place
+	reserved map[string]int // lanes chosen for the node that do not hold a place yet
+	changed  chan struct{}  // closed, and replaced, each time a lane ends
+}
+
+// CapacityOf is how many steps the part runs on the node at once: DefaultCapacity for a node the setting does not
+// name, and 0 for one it names so, where the part never builds.
+func (p *Places) CapacityOf(node string) int {
+	if n, ok := p.Capacity[node]; ok && n >= 0 {
+		return n
+	}
+	return DefaultCapacity
+}
+
+// Running is the steps in flight now, by node.
+func (p *Places) Running() map[string]int {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	out := make(map[string]int, len(p.running))
+	for n, c := range p.running {
+		if c > 0 {
+			out[n] = c
+		}
+	}
+	return out
+}
+
+// Reserved is the lanes chosen for a node that hold no place yet, by node.
+func (p *Places) Reserved() map[string]int {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	out := make(map[string]int, len(p.reserved))
+	for n, c := range p.reserved {
+		if c > 0 {
+			out[n] = c
+		}
+	}
+	return out
+}
+
+func (p *Places) init() {
+	if p.running == nil {
+		p.running = map[string]int{}
+	}
+	if p.reserved == nil {
+		p.reserved = map[string]int{}
+	}
+	if p.changed == nil {
+		p.changed = make(chan struct{})
+	}
+}
+
+// Acquire takes a place on the node, waiting while the node is at its capacity, and answers the function that gives it
+// back. A place reserved for the node by a choice is the one taken. It returns an error when ctx ends first, and then
+// gives up the reservation too.
+func (p *Places) Acquire(ctx context.Context, node string) (release func(), err error) {
+	for {
+		p.mu.Lock()
+		p.init()
+		if p.running[node] < p.CapacityOf(node) {
+			p.running[node]++
+			if p.reserved[node] > 0 {
+				p.reserved[node]--
+			}
+			p.mu.Unlock()
+			var once sync.Once
+			return func() {
+				once.Do(func() {
+					p.mu.Lock()
+					p.running[node]--
+					close(p.changed)
+					p.changed = make(chan struct{})
+					p.mu.Unlock()
+				})
+			}, nil
+		}
+		wait := p.changed
+		p.mu.Unlock()
+		select {
+		case <-wait:
+		case <-ctx.Done():
+			p.Cancel(node)
+			return nil, fmt.Errorf("waiting for a place on %s: %w", node, ctx.Err())
+		}
+	}
+}
+
+// Cancel gives up a place reserved for the node that will not be taken.
+func (p *Places) Cancel(node string) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	p.init()
+	if p.reserved[node] > 0 {
+		p.reserved[node]--
+	}
+}
+
+// choose orders the nodes (those with room first, counting the lanes running and the lanes reserved, then the fewest of
+// them, then by name), keeps the first want and reserves a place on each, all at once.
+func (p *Places) choose(nodes []string, want int) []string {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	p.init()
+	load := func(n string) int { return p.running[n] + p.reserved[n] }
+	sort.SliceStable(nodes, func(i, j int) bool {
+		ri, rj := load(nodes[i]) < p.CapacityOf(nodes[i]), load(nodes[j]) < p.CapacityOf(nodes[j])
+		if ri != rj {
+			return ri
+		}
+		if load(nodes[i]) != load(nodes[j]) {
+			return load(nodes[i]) < load(nodes[j])
+		}
+		return nodes[i] < nodes[j]
+	})
+	if len(nodes) > want {
+		nodes = nodes[:want]
+	}
+	for _, n := range nodes {
+		p.reserved[n]++
+	}
+	return nodes
+}

modules/mesh-delivery-builder/buildrun/places_test.go

@@ -0,0 +1,104 @@
+package buildrun
+
+import (
+	"context"
+	"strings"
+	"testing"
+	"time"
+)
+
+func acquireAsync(p *Places, node string) chan func() {
+	got := make(chan func(), 1)
+	go func() {
+		release, err := p.Acquire(context.Background(), node)
+		if err != nil {
+			close(got)
+			return
+		}
+		got <- release
+	}()
+	return got
+}
+
+func TestThreeStepsOnANodeOfCapacityTwoRunTwoAtOnceAndTheThirdStartsWhenOneEnds(t *testing.T) { // round 3
+	p := &Places{Capacity: map[string]int{"ace": 2}}
+	a, b := acquireAsync(p, "ace"), acquireAsync(p, "ace")
+	ra, rb := <-a, <-b
+	third := acquireAsync(p, "ace")
+	select {
+	case <-third:
+		t.Fatal("a third step started on a node of capacity 2 with two running")
+	case <-time.After(10 * time.Millisecond):
+	}
+	if p.Running()["ace"] != 2 {
+		t.Errorf("running = %v, want 2 on ace", p.Running())
+	}
+	ra()
+	select {
+	case r := <-third:
+		r()
+	case <-time.After(2 * time.Second):
+		t.Fatal("the third step did not start when one ended")
+	}
+	rb()
+}
+
+func TestANodeWithNoSettingRunsOneStepAtATime(t *testing.T) { // round 3
+	p := &Places{Capacity: map[string]int{"shanks": 3}}
+	first := <-acquireAsync(p, "g14")
+	second := acquireAsync(p, "g14")
+	select {
+	case <-second:
+		t.Fatal("two steps on a node without a setting")
+	case <-time.After(10 * time.Millisecond):
+	}
+	first()
+	r := <-second
+	r()
+	if p.CapacityOf("g14") != 1 || p.CapacityOf("shanks") != 3 {
+		t.Errorf("capacities = %d, %d", p.CapacityOf("g14"), p.CapacityOf("shanks"))
+	}
+}
+
+func TestAWaitingStepStopsWhenItsContextEnds(t *testing.T) { // round 3
+	p := &Places{}
+	r := <-acquireAsync(p, "ace")
+	defer r()
+	ctx, cancel := context.WithCancel(context.Background())
+	done := make(chan error, 1)
+	go func() { _, err := p.Acquire(ctx, "ace"); done <- err }()
+	cancel()
+	select {
+	case err := <-done:
+		if err == nil {
+			t.Error("Acquire returned no error for a cancelled wait")
+		}
+	case <-time.After(2 * time.Second):
+		t.Fatal("a cancelled wait did not return")
+	}
+}
+
+// The operator's decision of 2026-10-21 13:40: the builder builds on shanks and ace only; a capacity of 0 keeps it off a node.
+func TestACapacityOfZeroKeepsThePartOffTheNodeAndANodeNotNamedKeepsOne(t *testing.T) { // issue 1661
+	p := &Places{Capacity: map[string]int{"shanks": 3, "ace": 2, "g14": 0, "novox": 0}}
+	if p.CapacityOf("g14") != 0 || p.CapacityOf("novox") != 0 || p.CapacityOf("ace") != 2 || p.CapacityOf("other") != DefaultCapacity {
+		t.Errorf("capacities = %d %d %d %d, want 0 0 2 and the default for a node not named", p.CapacityOf("g14"), p.CapacityOf("novox"), p.CapacityOf("ace"), p.CapacityOf("other"))
+	}
+	entries := tcs("go", "go1.27.1", "ace", "g14", "novox", "shanks", "other")
+	for i := 0; i < 6; i++ {
+		nodes, _, err := ChooseNodes("go", entries, p, nil, 2)
+		if err != nil {
+			t.Fatal(err)
+		}
+		for _, n := range nodes {
+			if n == "g14" || n == "novox" {
+				t.Fatalf("choice %d: %v includes a node of capacity 0", i, nodes)
+			}
+		}
+	}
+	// Only nodes of capacity 0 report: nothing qualifies, and the build says why.
+	_, _, err := ChooseNodes("go", tcs("go", "go1.27.1", "g14", "novox"), p, nil, 2)
+	if err == nil || !strings.Contains(err.Error(), "capacity") {
+		t.Errorf("only capacity-0 nodes: error = %v, want it to name the capacity", err)
+	}
+}

modules/mesh-delivery-builder/buildrun/presence.go

@@ -0,0 +1,53 @@
+package buildrun
+
+import (
+	"sync"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// PresenceSet holds which nodes are online, as the watchman writes it (mesh-delivery-watchman_presence, key `<node>`, the
+// node-engine's connection): a node asleep or off the bus is offline and its build module cannot answer. A node the
+// watchman has no key of is not online. Safe for use from the watch and from a build at once.
+type PresenceSet struct {
+	mu     sync.Mutex
+	online map[string]bool
+}
+
+// Put takes a change of the presence bucket in and answers whether a node's online state changed. A part's key and a
+// value that is not a presence are left out.
+func (s *PresenceSet) Put(key string, value []byte, deleted bool) bool {
+	node, part, _, err := delivery.ParsePresenceKey(key)
+	if err != nil || part != "" {
+		return false
+	}
+	on := false
+	if !deleted {
+		p, err := delivery.DecodePresence(value)
+		if err != nil {
+			return false
+		}
+		on = p.Online
+	}
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if s.online[node] == on {
+		return false
+	}
+	if s.online == nil {
+		s.online = map[string]bool{}
+	}
+	if on {
+		s.online[node] = true
+	} else {
+		delete(s.online, node)
+	}
+	return true
+}
+
+// Online is whether the watchman last saw the node online.
+func (s *PresenceSet) Online(node string) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.online[node]
+}

modules/mesh-delivery-builder/buildrun/presence_test.go

@@ -0,0 +1,43 @@
+package buildrun
+
+import (
+	"testing"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+func presenceValue(t *testing.T, online bool) []byte {
+	t.Helper()
+	b, err := delivery.EncodePresence(delivery.Presence{Online: online})
+	if err != nil {
+		t.Fatal(err)
+	}
+	return b
+}
+
+func TestPresenceSetKnowsOnlyNodesTheWatchmanSawOnline(t *testing.T) { // 1607 review 3
+	var s PresenceSet
+	if s.Online("ace") {
+		t.Error("a node the watchman never wrote is online")
+	}
+	if !s.Put("ace", presenceValue(t, true), false) || !s.Online("ace") {
+		t.Error("ace online was not taken in")
+	}
+	if s.Put("ace", presenceValue(t, true), false) {
+		t.Error("the same presence again counted as a change")
+	}
+	if !s.Put("ace", presenceValue(t, false), false) || s.Online("ace") {
+		t.Error("ace going offline was not taken in")
+	}
+	s.Put("g14", presenceValue(t, true), false)
+	if !s.Put("g14", nil, true) || s.Online("g14") {
+		t.Error("a deleted key is still online")
+	}
+	// A part's instance (part.<part>.<instance>) is not a node.
+	if s.Put("part.mesh-delivery-builder.novox", presenceValue(t, true), false) || s.Online("part") {
+		t.Error("a part's key was taken for a node")
+	}
+	if s.Put("novox", []byte("junk"), false) {
+		t.Error("junk counted")
+	}
+}

modules/mesh-delivery-builder/buildrun/standing.go

@@ -0,0 +1,248 @@
+package buildrun
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"maps"
+	"slices"
+	"sort"
+	"sync"
+	"time"
+
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/process"
+)
+
+// A build module writes <node>.<language> of its toolchains state on every node it runs on, and nothing deletes the key
+// when the module leaves a node: no part writes another module's state, and the module is gone. A report of a node the
+// build module no longer runs on is therefore no builder's (issue 1940: mesh-build-node taken off ace on 2026-10-23 left
+// ace.typescript at v26.12.0, and every Node fingerprint said "builders disagree").
+//
+// ToolchainGate stands between the toolchains buckets and what takes their entries in (the indexer's PutToolchain, a
+// ToolchainSet): an entry is passed on only while the placement (the seat mesh-placement's state `placement`, held by
+// the assigner, delivery.PlacementBucket, read by delivery.Placed; ADR 0567, ADR 0549 §3) places its build module on
+// its node, and only once it was written since that placement; it is passed on as deleted otherwise, said once, and
+// passed on when its node writes it again. A report written before the placement is one an earlier run of the module
+// left (issue 1940, 2026-10-25 20:56: mesh-build-node put on ace again brought ace.typescript v26.12.0 of 2026-10-23
+// back into the agreement before the module ran there). Until the placement is settled, and while no node's placement
+// is held (before the assigner's adopt writes the first one, or where the state cannot be read), every entry is passed
+// on. Builders that run and report different versions still disagree: that refusal is the guard of novox/hq ADR 0465,
+// and it stays.
+//
+// This replaces the copies of the gate the indexer, the builder and the checker each kept over the controller's
+// assignments (issue 1940's subtask, issue 774: those go with the controller's lease, ADR 0549 §6).
+type ToolchainGate struct {
+	mu      sync.Mutex
+	modules map[string]bool                                           // the build modules whose toolchains pass the gate
+	forward func(module, key string, value []byte, deleted bool) bool // answers whether it changed what it holds
+	logf    func(format string, a ...any)
+	placed  *delivery.Placed
+	known   bool                         // the placement is settled
+	raw     map[string]map[string][]byte // module -> toolchains key -> value, as the bucket holds it
+	left    map[string]string            // <module>/<key> -> why it was said left out, so each reason is said once
+	// OnPlaced is told, outside the gate's lock, once the placement's history is read and after each revision of it
+	// FollowPlacement hears from then on (the counted nodes, Nodes, may have changed). Nil tells nobody.
+	OnPlaced func()
+}
+
+// NewToolchainGate is a gate over the toolchains of modules, passing what stands on to forward and saying with logf what
+// it leaves out.
+func NewToolchainGate(modules []string, forward func(module, key string, value []byte, deleted bool) bool, logf func(string, ...any)) *ToolchainGate {
+	g := &ToolchainGate{modules: map[string]bool{}, forward: forward, logf: logf, placed: delivery.NewPlaced(),
+		raw: map[string]map[string][]byte{}, left: map[string]string{}}
+	for _, m := range modules {
+		g.modules[m] = true
+	}
+	return g
+}
+
+// Toolchain takes one change of a build module's toolchains bucket in and answers whether what it passed on changed.
+func (g *ToolchainGate) Toolchain(module, key string, value []byte, deleted bool) bool {
+	g.mu.Lock()
+	defer g.mu.Unlock()
+	if g.raw[module] == nil {
+		g.raw[module] = map[string][]byte{}
+	}
+	if deleted {
+		delete(g.raw[module], key)
+	} else {
+		g.raw[module][key] = value
+	}
+	return g.pass(module, key)
+}
+
+// Placement takes one revision of the seat mesh-placement's placement in (at is when the bus wrote it) and answers whether what it
+// passed on changed. A value that does not read is said, and places nothing on its node.
+func (g *ToolchainGate) Placement(key string, value []byte, deleted bool, at time.Time) bool {
+	g.mu.Lock()
+	defer g.mu.Unlock()
+	was := g.placed.Seeded()
+	node, changed, err := g.placed.Put(key, value, deleted, at)
+	if err != nil {
+		g.logf("%s: %v (issue 1940)", delivery.PlacementBucket, err)
+	}
+	if !g.known {
+		return false
+	}
+	if was != g.placed.Seeded() {
+		// The first placement came, or the last went: every report's standing changed.
+		return g.all()
+	}
+	return g.again(node, changed)
+}
+
+// Nodes are the nodes the placement places any module on, sorted: the nodes the mesh counts (a node leaves the count
+// when the placement no longer names it; ADR 0624 §1). None until the placement is read.
+func (g *ToolchainGate) Nodes() []string {
+	var out []string
+	for node, modules := range g.placed.ByNode() {
+		if len(modules) > 0 {
+			out = append(out, node)
+		}
+	}
+	sort.Strings(out)
+	return out
+}
+
+// Settled says the placement's history is read: from now on only the reports of placed nodes pass, once a node's
+// placement is held. It answers whether what it passed on changed.
+func (g *ToolchainGate) Settled() bool {
+	g.mu.Lock()
+	defer g.mu.Unlock()
+	g.known = true
+	return g.all()
+}
+
+// all passes on every report again. The caller holds mu.
+func (g *ToolchainGate) all() bool {
+	changed := false
+	for _, module := range slices.Sorted(maps.Keys(g.raw)) {
+		for _, k := range slices.Sorted(maps.Keys(g.raw[module])) {
+			changed = g.pass(module, k) || changed
+		}
+	}
+	return changed
+}
+
+// again passes on every report of node by a build module among modules. The caller holds mu.
+func (g *ToolchainGate) again(node string, modules []string) bool {
+	changed := false
+	for _, module := range modules {
+		if !g.modules[module] {
+			continue
+		}
+		for _, k := range slices.Sorted(maps.Keys(g.raw[module])) {
+			if n, _, err := delivery.ParseToolchainKey(k); err == nil && n == node {
+				changed = g.pass(module, k) || changed
+			}
+		}
+	}
+	return changed
+}
+
+// pass hands one key on as it stands: its value when its node is placed and wrote it since (or the placement is not
+// known), deleted otherwise. The caller holds mu.
+func (g *ToolchainGate) pass(module, key string) bool {
+	value, held := g.raw[module][key]
+	if !held {
+		return g.forward(module, key, nil, true)
+	}
+	node, _, err := delivery.ParseToolchainKey(key)
+	why := ""
+	if err == nil && g.known && g.placed.Seeded() {
+		why = g.leftOut(module, node, value)
+	}
+	if why == "" {
+		delete(g.left, module+"/"+key)
+		return g.forward(module, key, value, false)
+	}
+	if g.left[module+"/"+key] != why {
+		g.left[module+"/"+key] = why
+		g.logf("%s.%s is left out of the agreed toolchain: %s (issue 1940)", delivery.ToolchainsBucket(module), key, why)
+	}
+	return g.forward(module, key, nil, true)
+}
+
+// leftOut is why a node's report is no builder's, or empty when it counts: the catalogue does not place the module on its
+// node, or the report was written before it did. A value that is no toolchain is passed on for its reader to refuse.
+// The caller holds mu.
+func (g *ToolchainGate) leftOut(module, node string, value []byte) string {
+	since, placed := g.placed.Since(node, module)
+	if !placed {
+		return fmt.Sprintf("the catalogue does not place %s on %s, so it is no builder", module, node)
+	}
+	tc, err := delivery.DecodeToolchain(value)
+	if err == nil && tc.At.Before(since) {
+		return fmt.Sprintf("it was written at %s, before %s was placed on %s at %s: it counts once %s writes it again",
+			tc.At.UTC().Format(time.RFC3339), module, node, since.UTC().Format(time.RFC3339), node)
+	}
+	return ""
+}
+
+// FollowPlacement reads the seat mesh-placement's placement with its history into gate, says it settled, and follows it; changed
+// is told whenever what the gate passes on changed. Where the state cannot be read or watched (not there, or this part
+// may not read it) it says so and the gate passes every report on: not fatal, since an indexer, builder or checker that
+// stops for it stops every delivery (issue 1945). An error of the watch after that ends on the channel.
+func FollowPlacement(ctx context.Context, js process.BucketOpener, gate *ToolchainGate, changed func(context.Context), logf func(string, ...any)) (<-chan error, error) {
+	errs := make(chan error, 1)
+	kv, err := js.KeyValue(ctx, delivery.PlacementBucket)
+	if err != nil {
+		logf("the state %s cannot be read, so every node's toolchain report counts, a build node's the catalogue does not place too (issue 1940): %v", delivery.PlacementBucket, err)
+		return errs, nil
+	}
+	w, err := kv.WatchAll(ctx, jetstream.IncludeHistory())
+	if err != nil {
+		logf("the state %s cannot be watched, so every node's toolchain report counts, a build node's the catalogue does not place too (issue 1940): %v", delivery.PlacementBucket, err)
+		return errs, nil
+	}
+	put := func(e jetstream.KeyValueEntry) bool {
+		return gate.Placement(e.Key(), e.Value(), e.Operation() != jetstream.KeyValuePut, e.Created())
+	}
+	for settled := false; !settled; {
+		select {
+		case <-ctx.Done():
+			_ = w.Stop()
+			return errs, ctx.Err()
+		case e, ok := <-w.Updates():
+			if !ok {
+				return errs, errors.New("the watch of " + delivery.PlacementBucket + " ended before it settled")
+			}
+			if e == nil {
+				settled = true
+				continue
+			}
+			put(e)
+		}
+	}
+	if gate.Settled() {
+		changed(ctx)
+	}
+	if gate.OnPlaced != nil {
+		gate.OnPlaced()
+	}
+	go func() {
+		defer func() { _ = w.Stop() }()
+		for {
+			select {
+			case <-ctx.Done():
+				errs <- ctx.Err()
+				return
+			case e, ok := <-w.Updates():
+				if !ok {
+					errs <- errors.New("the watch of " + delivery.PlacementBucket + " ended")
+					return
+				}
+				if e != nil && put(e) {
+					changed(ctx)
+				}
+				if e != nil && gate.OnPlaced != nil {
+					gate.OnPlaced()
+				}
+			}
+		}
+	}()
+	return errs, nil
+}

modules/mesh-delivery-builder/buildrun/standing_test.go

@@ -0,0 +1,263 @@
+package buildrun
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"fmt"
+	"log"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+func gateReport(t *testing.T, node, version string, at time.Time) (string, []byte) {
+	t.Helper()
+	key, err := delivery.ToolchainKey(node, "typescript")
+	if err != nil {
+		t.Fatal(err)
+	}
+	value, err := delivery.EncodeToolchain(delivery.Toolchain{Language: "typescript", Version: version, Recipe: "f59571cf4be75adf", At: at})
+	if err != nil {
+		t.Fatal(err)
+	}
+	return key, value
+}
+
+// placing is a value of the state `placement` placing modules on node.
+func placing(t *testing.T, node string, modules ...string) (string, []byte) {
+	t.Helper()
+	p := delivery.Placement{Node: node}
+	for _, m := range modules {
+		p.Modules = append(p.Modules, delivery.PlacedModule{Module: m})
+	}
+	values, err := delivery.PlacementValues(p)
+	if err != nil {
+		t.Fatal(err)
+	}
+	key, _ := delivery.PlacementNodeKey(node)
+	return key, values[key]
+}
+
+// placingLegacy is placing in the form before, `placement.<node>` (research 072 row 37).
+func placingLegacy(t *testing.T, node string, modules ...string) (string, []byte) {
+	t.Helper()
+	p := delivery.Placement{Node: node}
+	for _, m := range modules {
+		p.Modules = append(p.Modules, delivery.PlacedModule{Module: m})
+	}
+	key, _ := delivery.LegacyPlacementKey(node)
+	value, err := delivery.EncodePlacement(p)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return key, value
+}
+
+func agreedOf(set *ToolchainSet) (string, string) {
+	tc, none := delivery.AgreedToolchain(set.Entries("typescript"))
+	return tc.Version, none
+}
+
+// Issue 1940, the gate over the catalogue's placement (issue 774, ADR 0549 §3): a build node's report counts only while
+// the placement places its build module on its node, and only once written since; before the placement is settled, and
+// while no node's placement is held, every report counts. The live cases: mesh-build-node taken off ace left
+// ace.typescript at v26.12.0 against v26.12.1 on the three others; put on ace again, its report of 2026-10-23 06:29 came
+// back before the module ran there.
+func TestToolchainGate(t *testing.T) {
+	old := time.Date(2026, 10, 23, 6, 29, 18, 0, time.UTC)     // ace's report from its earlier run
+	placed := time.Date(2026, 10, 25, 19, 56, 45, 0, time.UTC) // mesh-build-node placed on ace again
+	three := []string{"g14", "novox", "shanks"}
+	start := func(t *testing.T, seeded bool) (*ToolchainGate, *ToolchainSet, *[]string) {
+		set := &ToolchainSet{}
+		said := &[]string{}
+		gate := NewToolchainGate([]string{GoBuildModule, NodeBuildModule}, set.Put, func(f string, a ...any) { *said = append(*said, fmt.Sprintf(f, a...)) })
+		for _, node := range three {
+			if seeded {
+				key, value := placing(t, node, NodeBuildModule)
+				gate.Placement(key, value, false, old.Add(-time.Hour))
+			}
+			key, value := gateReport(t, node, "v26.12.1", placed.Add(time.Minute))
+			gate.Toolchain(NodeBuildModule, key, value, false)
+		}
+		return gate, set, said
+	}
+
+	t.Run("not placed on ace: its report is no builder's", func(t *testing.T) {
+		gate, set, said := start(t, true)
+		key, value := gateReport(t, "ace", "v26.12.0", old)
+		gate.Toolchain(NodeBuildModule, key, value, false)
+		if a := delivery.ToolchainAgreement(set.Entries("typescript")); len(a.SittingOut) != 1 || a.SittingOut[0].Node != "ace" { // ADR 0584: the majority is agreed, ace's report counts as the one that sits out
+			t.Fatalf("before the placement is settled every report counts; got %+v", a)
+		}
+		k, v := placing(t, "ace", GoBuildModule) // another build module on ace: no matter
+		gate.Placement(k, v, false, old)
+		if !gate.Settled() {
+			t.Fatal("settling left ace's report out, so what was passed on changed")
+		}
+		if v, none := agreedOf(set); v != "v26.12.1" || none != "" {
+			t.Fatalf("the placed nodes agree on v26.12.1; got %q, %q", v, none)
+		}
+		if len(*said) != 1 || !strings.Contains((*said)[0], "does not place mesh-build-node on ace") {
+			t.Fatalf("ace's report is said left out once; said %q", *said)
+		}
+		if gate.Toolchain(NodeBuildModule, key, value, false) {
+			t.Fatal("a report of a node not placed changed what was passed on")
+		}
+		// Placed on ace with a report written since: it counts, and the builders really disagree.
+		k, v = placing(t, "ace", GoBuildModule, NodeBuildModule)
+		gate.Placement(k, v, false, old.Add(-time.Minute))
+		if a := delivery.ToolchainAgreement(set.Entries("typescript")); a.Toolchain.Version != "v26.12.1" || len(a.SittingOut) != 1 || a.SittingOut[0].Version != "v26.12.0" {
+			t.Fatalf("builders that run different versions: the majority is agreed and ace sits out; got %+v", a)
+		}
+		// Taken off ace again (its key deleted): its report goes again.
+		if !gate.Placement(k, nil, true, placed) {
+			t.Fatal("taking ace's placement away passed nothing on")
+		}
+		if v, none := agreedOf(set); v != "v26.12.1" || none != "" {
+			t.Fatalf("got %q, %q", v, none)
+		}
+		// A report deleted from the bucket goes whether its node is placed or not.
+		key, _ = gateReport(t, "g14", "v26.12.1", placed)
+		if !gate.Toolchain(NodeBuildModule, key, nil, true) || len(set.Entries("typescript")) != 2 {
+			t.Fatalf("deleting g14's report: %d entries left, want novox and shanks", len(set.Entries("typescript")))
+		}
+	})
+
+	for _, c := range []struct {
+		name   string
+		at     time.Time // when ace wrote its report
+		counts bool
+	}{
+		{"a report left before the placement", old, false},
+		{"a report written since the placement", placed.Add(30 * time.Second), true},
+	} {
+		t.Run(c.name, func(t *testing.T) {
+			gate, set, said := start(t, true)
+			k, v := placing(t, "ace") // ace's key, first heard placing nothing
+			gate.Placement(k, v, false, old.Add(-time.Hour))
+			gate.Settled()
+			k, v = placing(t, "ace", NodeBuildModule)
+			if gate.Placement(k, v, false, placed) {
+				t.Fatal("a placement with no report passed something on")
+			}
+			key, value := gateReport(t, "ace", "v26.12.0", c.at)
+			if got := gate.Toolchain(NodeBuildModule, key, value, false); got != c.counts {
+				t.Fatalf("ace's report passed on: %v, want %v", got, c.counts)
+			}
+			// ace's placement written again with another module beside: its standing does not move, nothing is said again.
+			k, v = placing(t, "ace", GoBuildModule, NodeBuildModule)
+			if gate.Placement(k, v, false, placed.Add(time.Minute)) {
+				t.Fatal("the same placement of mesh-build-node changed what was passed on")
+			}
+			if c.counts {
+				return
+			}
+			if v, none := agreedOf(set); v != "v26.12.1" || none != "" {
+				t.Fatalf("ace's left report is no builder's; got %q, %q", v, none)
+			}
+			if len(*said) != 1 || !strings.Contains((*said)[0], "before mesh-build-node was placed on ace at 2026-10-25T19:56:45Z") {
+				t.Fatalf("said %q, want once why ace's report is left out", *said)
+			}
+			key, value = gateReport(t, "ace", "v26.12.1", placed.Add(time.Minute))
+			if !gate.Toolchain(NodeBuildModule, key, value, false) || len(set.Entries("typescript")) != 4 {
+				t.Fatal("ace's new report was not passed on")
+			}
+		})
+	}
+
+	t.Run("no placement held: every report counts", func(t *testing.T) {
+		gate, set, _ := start(t, false)
+		key, value := gateReport(t, "ace", "v26.12.0", old)
+		gate.Toolchain(NodeBuildModule, key, value, false)
+		gate.Settled()
+		if n := len(set.Entries("typescript")); n != 4 {
+			t.Fatalf("before the first placement file every report counts; got %d", n)
+		}
+		k, v := placing(t, "g14", NodeBuildModule)
+		if !gate.Placement(k, v, false, old.Add(-time.Hour)) || len(set.Entries("typescript")) != 1 {
+			t.Fatalf("the first placement leaves every node it does not place out; got %d", len(set.Entries("typescript")))
+		}
+		if !gate.Placement(k, nil, true, placed) || len(set.Entries("typescript")) != 4 {
+			t.Fatal("the last placement gone: every report counts again")
+		}
+	})
+
+	t.Run("the history: a module in the first revision heard of a key stands since before it", func(t *testing.T) {
+		p := delivery.NewPlaced()
+		// ace in the form before, then converted: its module stands since before, the legacy key read no more.
+		k, v := placingLegacy(t, "ace", NodeBuildModule)
+		p.Put(k, v, false, old)
+		k, v = placing(t, "ace", NodeBuildModule)
+		if _, changed, err := p.Put(k, v, false, placed); len(changed) != 0 || err != nil {
+			t.Errorf("the conversion of ace's key changed %v, %v", changed, err)
+		}
+		if _, changed, _ := p.Put("ace."+NodeBuildModule, []byte("{}"), false, placed); len(changed) != 0 {
+			t.Errorf("a module key says which modules stand: %v", changed)
+		}
+		if k, v := placingLegacy(t, "ace"); true {
+			if _, changed, _ := p.Put(k, v, false, placed); len(changed) != 0 {
+				t.Errorf("the legacy key is read after the node key: %v", changed)
+			}
+		}
+		k2, v2 := placing(t, "g14")
+		p.Put(k2, v2, false, old)
+		k2, v2 = placing(t, "g14", NodeBuildModule)
+		if _, changed, _ := p.Put(k2, v2, false, placed); strings.Join(changed, ",") != NodeBuildModule {
+			t.Errorf("a module placed says changed %v", changed)
+		}
+		if _, _, err := p.Put("placement.novox", []byte("not json"), false, old); err == nil {
+			t.Error("a value that does not read was not said")
+		}
+		if s, ok := p.Since("ace", NodeBuildModule); !ok || !s.IsZero() {
+			t.Errorf("ace's module stands since %v, %v; want the zero time", s, ok)
+		}
+		if s, ok := p.Since("g14", NodeBuildModule); !ok || !s.Equal(placed) {
+			t.Errorf("g14's module stands since %v, %v; want the revision that placed it", s, ok)
+		}
+		if got := p.PlacedNodes(NodeBuildModule); strings.Join(got, ",") != "ace,g14" || len(p.ByNode()) != 2 || !p.Seeded() {
+			t.Errorf("PlacedNodes = %v, ByNode = %v", got, p.ByNode())
+		}
+	})
+
+	t.Run("a placement the bus refuses is said, and the part goes on", func(t *testing.T) {
+		var logs bytes.Buffer
+		logger := log.New(&logs, "", 0)
+		refused := errors.New("nats: permissions violation for publish to $JS.API.CONSUMER.CREATE.KV_mesh-delivery-assigner_placement")
+		gate, _, _ := start(t, false)
+		for _, bus := range []refusingBus{{err: refused}, {refuseOpen: true, err: refused}} {
+			if _, err := FollowPlacement(context.Background(), bus, gate, func(context.Context) {}, logger.Printf); err != nil {
+				t.Errorf("a refused placement stopped the start: %v", err)
+			}
+		}
+		if !strings.Contains(logs.String(), "cannot be watched") || !strings.Contains(logs.String(), "cannot be read") {
+			t.Errorf("the refusals were not said: %q", logs.String())
+		}
+	})
+}
+
+// refusingBus is a bus that refuses: every open (refuseOpen), or every watch of a bucket it opens, with err.
+type refusingBus struct {
+	refuseOpen bool
+	err        error
+}
+
+func (r refusingBus) KeyValue(context.Context, string) (jetstream.KeyValue, error) {
+	if r.refuseOpen {
+		return nil, r.err
+	}
+	return refusedWatch{err: r.err}, nil
+}
+
+type refusedWatch struct {
+	jetstream.KeyValue
+	err error
+}
+
+func (r refusedWatch) WatchAll(context.Context, ...jetstream.WatchOpt) (jetstream.KeyWatcher, error) {
+	return nil, r.err
+}

modules/mesh-delivery-builder/buildrun/steps.go

@@ -0,0 +1,67 @@
+package buildrun
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"time"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// Caller calls a tool of a module on one named machine (mesh-sdk process.Conn.CallOn; ADR 0469 clause 3).
+type Caller interface {
+	CallOn(node, key string, body any) (json.RawMessage, error)
+}
+
+// Steps waits for the end of a build module's long step: the value of its key `<node>.<id>` in the module's steps state
+// (ADR 0469 clause 2) once its state is not running. It is a watch of that key, not a poll; it returns when the step
+// ends or ctx does.
+type Steps interface {
+	Wait(ctx context.Context, module, key string) (delivery.Step, error)
+}
+
+// Runner runs a build module's long steps: the call answers at once with the step's key, and the result is read from that
+// key when the step ends (ADR 0469 clause 2).
+type Runner struct {
+	Caller Caller
+	Steps  Steps
+	// Bound is how long a step may run before the builder stops waiting for it.
+	Bound time.Duration
+}
+
+// Run calls tool of the build module on node with args, waits for the step's end and answers its result. A step that
+// failed or was refused is an error naming the node, the state and the reason.
+func (r Runner) Run(ctx context.Context, module, node, tool string, args map[string]any) (json.RawMessage, error) {
+	raw, err := r.Caller.CallOn(node, module+"."+tool, args)
+	if err != nil {
+		return nil, fmt.Errorf("%s on %s: %w", tool, node, err)
+	}
+	var answer struct {
+		Step  string `json:"step"`
+		Key   string `json:"key"`
+		State string `json:"state"`
+	}
+	if err := json.Unmarshal(raw, &answer); err != nil {
+		return nil, fmt.Errorf("%s on %s answered what is not a step: %w", tool, node, err)
+	}
+	if answer.Key == "" {
+		return nil, fmt.Errorf("%s on %s answered no step key: %s", tool, node, raw)
+	}
+	if n, _, err := delivery.ParseStepKey(answer.Key); err != nil || n != node {
+		return nil, fmt.Errorf("%s on %s answered the step key %q, which is not a key of that node", tool, node, answer.Key)
+	}
+	wait, cancel := context.WithTimeoutCause(ctx, r.Bound, fmt.Errorf("the step %s did not end within %s", answer.Key, r.Bound))
+	defer cancel()
+	step, err := r.Steps.Wait(wait, module, answer.Key)
+	if err != nil {
+		if cause := context.Cause(wait); cause != nil && ctx.Err() == nil {
+			err = cause
+		}
+		return nil, fmt.Errorf("%s on %s: %w", tool, node, err)
+	}
+	if step.State != delivery.StepPassed {
+		return nil, fmt.Errorf("%s on %s: the step %s %s: %s", tool, node, answer.Key, step.State, step.Reason)
+	}
+	return step.Result, nil
+}

modules/mesh-delivery-builder/buildrun/steps_test.go

@@ -0,0 +1,125 @@
+package buildrun
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+type call struct {
+	node, key string
+	body      any
+}
+
+// fakeCaller answers a long tool as the build modules do: at once, with the step and its key.
+type fakeCaller struct {
+	calls  []call
+	answer string
+	err    error
+}
+
+func (f *fakeCaller) CallOn(node, key string, body any) (json.RawMessage, error) {
+	f.calls = append(f.calls, call{node, key, body})
+	if f.err != nil {
+		return nil, f.err
+	}
+	return json.RawMessage(f.answer), nil
+}
+
+// fakeSteps holds the steps values by `<module>/<key>`; Wait on a key it does not hold blocks until the context ends.
+type fakeSteps struct {
+	mu    sync.Mutex
+	steps map[string]delivery.Step
+	// during, when set, is called as a wait starts and the function it answers as the wait ends.
+	during func(key string) func()
+}
+
+func (f *fakeSteps) Wait(ctx context.Context, module, key string) (delivery.Step, error) {
+	f.mu.Lock()
+	s, ok := f.steps[module+"/"+key]
+	during := f.during
+	f.mu.Unlock()
+	if ok {
+		if during != nil {
+			defer during(key)()
+		}
+		return s, nil
+	}
+	<-ctx.Done()
+	return delivery.Step{}, context.Cause(ctx)
+}
+
+func stepAt(node, id, state, reason string, result string) delivery.Step {
+	s := delivery.Step{ID: id, Tool: "build_go_fetch", Node: node, State: state, Reason: reason}
+	if result != "" {
+		s.Result = json.RawMessage(result)
+	}
+	return s
+}
+
+func runCallsTheToolOnTheNodeAndReadsTheStepsKey(t *testing.T) { // 1607/AC5
+	caller := &fakeCaller{answer: `{"step":"abc1","key":"ace.abc1","state":"running"}`}
+	steps := &fakeSteps{steps: map[string]delivery.Step{"mesh-build-go/ace.abc1": stepAt("ace", "abc1", delivery.StepPassed, "", `{"workspace":"w1","commit":"c"}`)}}
+	res, err := Runner{Caller: caller, Steps: steps, Bound: time.Second}.Run(context.Background(), "mesh-build-go", "ace", "build_go_fetch", map[string]any{"repository": "novox/r", "commit": "c"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(caller.calls) != 1 || caller.calls[0].node != "ace" || caller.calls[0].key != "mesh-build-go.build_go_fetch" {
+		t.Errorf("calls = %+v, want one on ace for mesh-build-go.build_go_fetch", caller.calls)
+	}
+	var fr struct{ Workspace string }
+	if err := json.Unmarshal(res, &fr); err != nil || fr.Workspace != "w1" {
+		t.Errorf("result = %s (%v), want the step's result", res, err)
+	}
+}
+
+func runFailsOnAFailedOrRefusedStepNamingItsReason(t *testing.T) { // 1607/AC5
+	for _, state := range []string{delivery.StepFailed, delivery.StepRefused} {
+		caller := &fakeCaller{answer: `{"step":"abc1","key":"ace.abc1","state":"running"}`}
+		steps := &fakeSteps{steps: map[string]delivery.Step{"mesh-build-go/ace.abc1": stepAt("ace", "abc1", state, "go is go1.26.0, the recipe builds with go1.27.1", "")}}
+		_, err := Runner{Caller: caller, Steps: steps, Bound: time.Second}.Run(context.Background(), "mesh-build-go", "ace", "build_go_build", nil)
+		if err == nil || !strings.Contains(err.Error(), "go1.27.1") || !strings.Contains(err.Error(), state) || !strings.Contains(err.Error(), "ace") {
+			t.Errorf("%s: error = %v, want the node, the state and the reason", state, err)
+		}
+	}
+}
+
+func runStopsWaitingAtTheBound(t *testing.T) { // 1607/AC5
+	caller := &fakeCaller{answer: `{"step":"abc1","key":"ace.abc1","state":"running"}`}
+	_, err := Runner{Caller: caller, Steps: &fakeSteps{}, Bound: 20 * time.Millisecond}.Run(context.Background(), "mesh-build-go", "ace", "build_go_build", nil)
+	if err == nil || !strings.Contains(err.Error(), "ace.abc1") || !strings.Contains(err.Error(), "did not end") {
+		t.Errorf("error = %v, want the step key and that it did not end within its bound", err)
+	}
+}
+
+func runRefusesAnAnswerWithNoKeyAndAKeyOfAnotherNode(t *testing.T) { // 1607/AC5
+	for _, answer := range []string{`{"state":"running"}`, `{"step":"abc1","key":"novox.abc1","state":"running"}`, `not json`} {
+		_, err := Runner{Caller: &fakeCaller{answer: answer}, Steps: &fakeSteps{}, Bound: time.Second}.Run(context.Background(), "mesh-build-go", "ace", "build_go_fetch", nil)
+		if err == nil {
+			t.Errorf("answer %s: no error", answer)
+		}
+	}
+}
+
+func runReturnsTheCallsOwnError(t *testing.T) { // 1607/AC5
+	boom := errors.New("no responders")
+	_, err := Runner{Caller: &fakeCaller{err: boom}, Steps: &fakeSteps{}, Bound: time.Second}.Run(context.Background(), "mesh-build-go", "ace", "build_go_fetch", nil)
+	if !errors.Is(err, boom) || !strings.Contains(err.Error(), "ace") {
+		t.Errorf("error = %v, want the call's error naming the node", err)
+	}
+}
+
+// A step run on its node and read from its steps key, one table of cases (the test budget).
+func TestRunningAStepOnANode(t *testing.T) {
+	t.Run("run calls the tool on the node and reads the steps key", runCallsTheToolOnTheNodeAndReadsTheStepsKey)
+	t.Run("run fails on a failed or refused step naming its reason", runFailsOnAFailedOrRefusedStepNamingItsReason)
+	t.Run("run stops waiting at the bound", runStopsWaitingAtTheBound)
+	t.Run("run refuses an answer with no key and a key of another node", runRefusesAnAnswerWithNoKeyAndAKeyOfAnotherNode)
+	t.Run("run returns the calls own error", runReturnsTheCallsOwnError)
+}

modules/mesh-delivery-builder/buildrun/toolchains.go

@@ -0,0 +1,64 @@
+package buildrun
+
+import (
+	"sync"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// LanguageOf is the language each build module's toolchains state holds (the indexer's ToolchainModules, reversed).
+var LanguageOf = map[string]string{GoBuildModule: "go", NodeBuildModule: "typescript"}
+
+// ToolchainSet holds what the build modules' toolchains buckets hold: each node's entry of a language, as the watches
+// put them in. Safe for use from the watches and from a build at once.
+type ToolchainSet struct {
+	mu sync.Mutex
+	by map[string]map[string]delivery.Toolchain // language -> node -> entry
+}
+
+// Put takes a change of a build module's toolchains bucket in: a put of a node's entry (key <node>.<language>) or its
+// delete. It answers whether the language's entries changed (a node's version or recipe, or a node appearing or going).
+// A key or a value that is not an entry of the module's language is left out.
+func (s *ToolchainSet) Put(module, key string, value []byte, deleted bool) bool {
+	language, ok := LanguageOf[module]
+	if !ok {
+		return false
+	}
+	node, keyLanguage, err := delivery.ParseToolchainKey(key)
+	if err != nil || keyLanguage != language {
+		return false
+	}
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if deleted {
+		if _, had := s.by[language][node]; !had {
+			return false
+		}
+		delete(s.by[language], node)
+		return true
+	}
+	tc, err := delivery.DecodeToolchain(value)
+	if err != nil || tc.Language != language {
+		return false
+	}
+	if s.by == nil {
+		s.by = map[string]map[string]delivery.Toolchain{}
+	}
+	if s.by[language] == nil {
+		s.by[language] = map[string]delivery.Toolchain{}
+	}
+	cur, had := s.by[language][node]
+	s.by[language][node] = tc
+	return !had || cur.Version != tc.Version || cur.Recipe != tc.Recipe
+}
+
+// Entries are the nodes' entries of a language, in no particular order.
+func (s *ToolchainSet) Entries(language string) []delivery.NodeToolchain {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	var out []delivery.NodeToolchain
+	for node, tc := range s.by[language] {
+		out = append(out, delivery.NodeToolchain{Node: node, Toolchain: tc})
+	}
+	return out
+}

modules/mesh-delivery-builder/buildrun/toolchains_test.go

@@ -0,0 +1,49 @@
+package buildrun
+
+import (
+	"testing"
+	"time"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+func tcValue(t *testing.T, language, version string) []byte {
+	t.Helper()
+	b, err := delivery.EncodeToolchain(delivery.Toolchain{Language: language, Version: version, Recipe: "1", At: time.Now()})
+	if err != nil {
+		t.Fatal(err)
+	}
+	return b
+}
+
+func TestToolchainSetKeepsEachNodesEntryByLanguageAndSaysWhenOneChanged(t *testing.T) { // 1607/AC6
+	var s ToolchainSet
+	if !s.Put(GoBuildModule, "novox.go", tcValue(t, "go", "go1.27.1"), false) {
+		t.Error("a first entry did not count as a change")
+	}
+	if s.Put(GoBuildModule, "novox.go", tcValue(t, "go", "go1.27.1"), false) {
+		t.Error("the same entry again counted as a change")
+	}
+	s.Put(GoBuildModule, "ace.go", tcValue(t, "go", "go1.27.1"), false)
+	s.Put(NodeBuildModule, "ace.typescript", tcValue(t, "typescript", "tsc5"), false)
+	if got := s.Entries("go"); len(got) != 2 {
+		t.Errorf("go entries = %+v, want two", got)
+	}
+	if got := s.Entries("typescript"); len(got) != 1 || got[0].Node != "ace" || got[0].Version != "tsc5" {
+		t.Errorf("typescript entries = %+v", got)
+	}
+	if !s.Put(GoBuildModule, "ace.go", nil, true) || len(s.Entries("go")) != 1 {
+		t.Error("a delete did not remove the node's entry")
+	}
+	// What is not a toolchain of the module's language is left out.
+	s = ToolchainSet{}
+	if s.Put(GoBuildModule, "novox.typescript", tcValue(t, "typescript", "x"), false) {
+		t.Error("a typescript toolchain in the go build module's bucket counted")
+	}
+	if s.Put(GoBuildModule, "novox.go", []byte("not json"), false) || s.Put("other-module", "novox.go", tcValue(t, "go", "x"), false) {
+		t.Error("garbage or an unknown module counted")
+	}
+	if len(s.Entries("go")) != 0 {
+		t.Error("an entry was kept")
+	}
+}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder-tools/main.go

@@ -14,21 +14,119 @@ import (
 	"sync"
 	"time"
 
+	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun"
 	stdio "git.novox.be/novox/mesh-sdk/go"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
+	"git.novox.be/novox/mesh-sdk/go/handacts"
+	"git.novox.be/novox/mesh-sdk/go/views"
+
+	"git.novox.be/novox/mesh-delivery/sdk/enginereads"
 
 	"mesh-delivery-builder/internal/build"
+	"mesh-delivery-builder/internal/versions"
 )
 
+// EngineReadsTool lists, asks again and drops what each counted node's engine reads, as the builder keeps it.
+const EngineReadsTool = "builder_engine_reads"
+
 // queueAsker writes a queues value and waits for the builder's answer to it.
 type queueAsker func(key string, value []byte) (json.RawMessage, error)
 
 // Tools are the builder's tools: stuck reads, askAgain writes the reasks value, queue writes a queues value and waits for
 // the builder's read, buildAgain writes a reasks value of mode build and waits for the builder's answer.
-func Tools(r build.StuckReader, askAgain func(key string, value []byte) error, queue, buildAgain queueAsker, now func() time.Time) []stdio.Tool {
+// tags writes a tag-asks value and waits for the builder's answer; ta reads tag-asks.
+func Tools(r build.StuckReader, askAgain func(key string, value []byte) error, queue, buildAgain queueAsker, since build.LogSince, now func() time.Time, vs versions.Reader,
+	tags queueAsker, ta, fw, of versions.Reader) []stdio.Tool {
 	str := func(args map[string]any, k string) string { s, _ := args[k].(string); return strings.TrimSpace(s) }
+	// handAct writes a reasks value of a versions hand act and answers the builder's answer, or its refusal as an error.
+	handAct := func(key string, value []byte, err error) (any, error) {
+		if err != nil {
+			return nil, err
+		}
+		raw, err := buildAgain(key, value)
+		if err != nil {
+			return nil, err
+		}
+		a, err := build.DecodeReAsk(raw)
+		if err != nil {
+			return nil, err
+		}
+		if a.Refused {
+			return nil, errors.New(a.Answer)
+		}
+		return map[string]any{"key": key, "name": a.Name, "do": a.Do, "version": a.Version, "answer": a.Answer}, nil
+	}
+	tagAct := func(key string, value []byte, err error) (any, error) {
+		if err != nil {
+			return nil, err
+		}
+		raw, err := tags(key, value)
+		if err != nil {
+			return nil, err
+		}
+		return versions.DecodeTagAsk(raw)
+	}
+	nameFP := map[string]any{"type": "object", "required": []string{"name", "fp", "why"}, "properties": map[string]any{
+		"name": map[string]any{"type": "string", "description": "the numbered name, <module>/<artifact>, as builder_versions lists it"},
+		"fp":   map[string]any{"type": "string", "description": "the fingerprint, src2:<hex>"},
+		"why":  map[string]any{"type": "string", "description": "why, in plain words"}}}
+	branch := func(head bool) map[string]any {
+		req := []string{"repository", "branch", "why"}
+		props := map[string]any{
+			"repository": map[string]any{"type": "string", "description": "<owner>/<name>"},
+			"branch":     map[string]any{"type": "string", "description": "the branch; its cleaned name is the tag"},
+			"why":        map[string]any{"type": "string", "description": "why, in plain words"}}
+		if head {
+			req = append(req, "head")
+			props["head"] = map[string]any{"type": "string", "description": "the commit the tagged version is built from"}
+		}
+		return map[string]any{"type": "object", "required": req, "properties": props}
+	}
 	return []stdio.Tool{
+		{Name: versions.PublishAgainTool, Description: versions.PublishAgainDescription, Input: nameFP,
+			Run: func(args map[string]any) (any, error) {
+				return handAct(build.NewPublishAgain(str(args, "name"), str(args, "fp"), str(args, "why"), stdio.CallerOf(args), now()))
+			}},
+		{Name: versions.FloorAgainTool, Description: versions.FloorAgainDescription,
+			Input: map[string]any{"type": "object", "required": []string{"name", "why"}, "properties": map[string]any{
+				"name": map[string]any{"type": "string", "description": "the numbered name, <module>/<artifact>"},
+				"why":  map[string]any{"type": "string", "description": "why, in plain words"}}},
+			Run: func(args map[string]any) (any, error) {
+				return handAct(build.NewFloorAgain(str(args, "name"), str(args, "why"), stdio.CallerOf(args), now()))
+			}},
+		{Name: versions.TagTool, Description: versions.TagDescription, Input: branch(true),
+			Run: func(args map[string]any) (any, error) {
+				return tagAct(versions.NewTagAsk(str(args, "repository"), str(args, "branch"), str(args, "head"), str(args, "why"), stdio.CallerOf(args), now()))
+			}},
+		{Name: versions.UntagTool, Description: versions.UntagDescription, Input: branch(false),
+			Run: func(args map[string]any) (any, error) {
+				return tagAct(versions.NewUntag(str(args, "repository"), str(args, "branch"), str(args, "why"), stdio.CallerOf(args), now()))
+			}},
+		{Name: versions.TagAsksTool, Description: versions.TagAsksDescription,
+			Input: map[string]any{"type": "object", "properties": map[string]any{
+				"repository": map[string]any{"type": "string", "description": "only this repository's asks, <owner>/<name>"}}},
+			Run: func(args map[string]any) (any, error) { return versions.AnswerTagAsks(ta, str(args, "repository")) }},
+		{Name: versions.OldFormTool, Description: versions.OldFormDescription,
+			Input: map[string]any{"type": "object", "properties": map[string]any{
+				"drop": map[string]any{"type": "string", "description": "a retired node to drop from the count by hand"},
+				"why":  map[string]any{"type": "string", "description": "with drop: why, in plain words"}}},
+			Run: func(args map[string]any) (any, error) {
+				if node := str(args, "drop"); node != "" {
+					return handAct(build.NewOldFormDrop(node, str(args, "why"), stdio.CallerOf(args), now()))
+				}
+				return versions.AnswerOldForm(of)
+			}},
+		{Name: versions.FloorWaitsTool, Description: versions.FloorWaitsDescription,
+			Input: map[string]any{"type": "object", "properties": map[string]any{}},
+			Run:   func(map[string]any) (any, error) { return versions.AnswerFloorWaits(fw) }},
+		{Name: versions.VersionsTool, Description: versions.VersionsDescription,
+			Input: map[string]any{"type": "object", "required": []string{"name"}, "properties": map[string]any{
+				"name":    map[string]any{"type": "string", "description": "the package, image, bundle or archive name"},
+				"version": map[string]any{"type": "string", "description": "one version, to ask whether it is recorded"},
+				"digest":  map[string]any{"type": "string", "description": "with version: the digest the holder received"}}},
+			Run: func(args map[string]any) (any, error) {
+				return versions.AnswerVersions(context.Background(), vs, str(args, "name"), str(args, "version"), str(args, "digest"))
+			}},
 		{Name: build.StuckTool,
 			Description: "Every build key that waits (building or queued), oldest first: its module, fingerprint, step words and since when, and each ask it " +
 				"waits on by language with its id, when it was put, its asking (1 for the first; the builder asks an ask again when it can no longer be " +
@@ -94,6 +192,48 @@ func Tools(r build.StuckReader, askAgain func(key string, value []byte) error, q
 				return map[string]any{"key": key, "revision": r.Revision, "asks": r.Asks, "answer": r.Answer,
 					"next": build.StuckTool + " shows the key and its asks while they wait"}, nil
 			}},
+		{Name: delivery.BuildsSinceTool,
+			Description: "Every build that ended since a time, oldest first, from the builder's log build-log (kept 30 days): per build its module, " +
+				"fingerprint, source revision, repository, directory, commit and ref, the build node, when it ended, its outcome (done, failed or " +
+				"queued), the manifest built, the bases it was built against and each artifact made with its digest and reference. more says the " +
+				"log held more than one answer carries: ask again from the last build's time. What the operator's command nox builds reads. Read-only.",
+			Input: map[string]any{"type": "object", "required": []string{"since"}, "properties": map[string]any{
+				"since": map[string]any{"type": "string", "description": "RFC 3339 time; the builds that ended at or after it"}}},
+			Run: func(args map[string]any) (any, error) {
+				at, err := time.Parse(time.RFC3339Nano, str(args, "since"))
+				if err != nil {
+					return nil, fmt.Errorf("since %q is not an RFC 3339 time: %w", str(args, "since"), err)
+				}
+				return build.BuildsSince(since, at)
+			}},
+		{Name: build.AnnounceAgainTool,
+			Description: "Announce a done build again (take in again, compose again): the builder writes the done key of module and fingerprint " +
+				"again, unchanged, as a new revision of the same key (its content, artifacts and manifest stay identical), so the controller's " +
+				"take-in hears it and composes the module and writes its grant again. Use it when a done build was taken in but its composition " +
+				"or grant is gone and every want is refused for it. Answers the new revision. Refuses a key that is not done: " + build.BuildAgainTool +
+				" builds a failed key again, " + build.AskAgainTool + " asks a waiting key's asks again.",
+			Input: map[string]any{"type": "object", "required": []string{"module", "fp", "why"}, "properties": map[string]any{
+				"module": map[string]any{"type": "string", "description": "the module's name"},
+				"fp":     map[string]any{"type": "string", "description": "its new-form fingerprint, src2:<hex>"},
+				"why":    map[string]any{"type": "string", "description": "why it is announced again, in plain words"}}},
+			Run: func(args map[string]any) (any, error) {
+				key, value, err := build.NewAnnounceAgain(str(args, "module"), str(args, "fp"), str(args, "why"), stdio.CallerOf(args), now())
+				if err != nil {
+					return nil, err
+				}
+				raw, err := buildAgain(key, value)
+				if err != nil {
+					return nil, err
+				}
+				r, err := build.DecodeReAsk(raw)
+				if err != nil {
+					return nil, err
+				}
+				if r.Refused || r.Revision == 0 {
+					return nil, errors.New(r.Answer)
+				}
+				return map[string]any{"key": key, "revision": r.Revision, "answer": r.Answer}, nil
+			}},
 		{Name: build.SeatQueueTool,
 			Description: "What waits on a build seat's stream (SEAT_NODE_BUILD_<LANGUAGE>), as the builder reads it: the stream's message count and " +
 				"sequences, and per kind (delivery, check, recheck) its messages oldest first, at most limit each, with sequence, ask id, when asked " +
@@ -222,7 +362,65 @@ func main() {
 		a, err := build.DecodeReAsk(v)
 		return err == nil && !a.Answered.IsZero()
 	})
-	if err := stdio.Serve("", Tools(r, put, askQueue(stdio.State(build.QueuesState), 25*time.Second), buildAgain, time.Now)); err != nil {
+	vs := stdio.State(versions.State)
+	vr := versions.Reader{Keys: vs.Keys, Get: func(key string) (json.RawMessage, bool, error) {
+		e, err := vs.Get(key)
+		if err != nil || e == nil {
+			return nil, false, err
+		}
+		return e.Value, true, nil
+	}}
+	ts := stdio.State(versions.TagAsksState)
+	tags := askKept(ts, versions.TagAsksState, versions.TagAsksBucket, "the ask", 25*time.Second, func(v []byte) bool {
+		a, err := versions.DecodeTagAsk(v)
+		return err == nil && !a.Answered.IsZero()
+	})
+	tr := versions.Reader{Keys: ts.Keys, Get: func(key string) (json.RawMessage, bool, error) {
+		e, err := ts.Get(key)
+		if err != nil || e == nil {
+			return nil, false, err
+		}
+		return e.Value, true, nil
+	}}
+	fs := stdio.State(versions.FloorWaitsState)
+	fr := versions.Reader{Keys: fs.Keys, Get: func(key string) (json.RawMessage, bool, error) {
+		e, err := fs.Get(key)
+		if err != nil || e == nil {
+			return nil, false, err
+		}
+		return e.Value, true, nil
+	}}
+	ofs := stdio.State(versions.OldFormState)
+	ofr := versions.Reader{Keys: ofs.Keys, Get: func(key string) (json.RawMessage, bool, error) {
+		e, err := ofs.Get(key)
+		if err != nil || e == nil {
+			return nil, false, err
+		}
+		return e.Value, true, nil
+	}}
+	bs := stdio.State(versions.BoundsState)
+	br := versions.Reader{Keys: bs.Keys, Get: func(key string) (json.RawMessage, bool, error) {
+		e, err := bs.Get(key)
+		if err != nil || e == nil {
+			return nil, false, err
+		}
+		return e.Value, true, nil
+	}}
+	tools := Tools(r, put, askQueue(stdio.State(build.QueuesState), 25*time.Second), buildAgain, stdio.Log(delivery.BuilderLog).Since, time.Now, vr, tags, tr, fr, ofr)
+	// The builder's expiring keys (state bounds): what each bounds and when it ends.
+	tools = append(tools, stdio.Tool{Name: versions.BoundsTool, Description: versions.BoundsDescription,
+		Input: map[string]any{"type": "object", "properties": map[string]any{}},
+		Run: func(map[string]any) (any, error) {
+			rows, err := versions.AnswerBounds(br, time.Now())
+			return map[string]any{"bounds": rows}, err
+		}})
+	// What each counted node's engine reads, as the builder keeps it (ADR 0618 §2, ADR 0624 §1): listed, one node asked
+	// again, or one node's key dropped.
+	tools = append(tools, enginereads.Tool(EngineReadsTool, "the builder", enginereads.KeptState(stdio.State("engine-reads")), true, time.Now))
+	// builder_first_views and builder_first_view_again: where the builder's first views of the indexer's and the assigner's
+	// states stand, and asking one again by hand (ADR 0615, DLV-M1).
+	tools = append(tools, views.StatusTools(delivery.BuilderModule, "builder_first_views", "builder_first_view_again", stdio.State(views.StatusState), handacts.Recorder{Ask: stdio.Ask}, time.Now)...)
+	if err := stdio.Serve("", tools); err != nil {
 		fmt.Fprintf(os.Stderr, "[mesh-delivery-builder-tools] %v\n", err)
 		os.Exit(1)
 	}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/branchend.go

@@ -0,0 +1,174 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"strings"
+	"time"
+
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/health"
+
+	"mesh-delivery-builder/internal/build"
+	"mesh-delivery-builder/internal/versions"
+)
+
+// forgeStream is the forge bridge's stream `forge` as the bus names it, where the builder's durable consumer hears a
+// branch's end (design 51 *Tagged versions*).
+const forgeStream = "FORGE"
+
+// forgeBranchDeleted is the forge bridge's kind for a branch's end (delivery.ForgeBranchDeleted in the group's mesh-sdk).
+const forgeBranchDeleted = "branch-deleted"
+
+// checkerAsksStream is the checker's family `asks` as the bus names it, and tagWantedSubject its event tag-wanted
+// (design 51 *Tagged versions*, DLV-C3): on the checker's own stream, so its subject is mesh.stream.<module>.event.*.
+const (
+	checkerAsksStream = "ASKS"
+	tagWantedSubject  = "mesh.stream." + delivery.CheckerModule + ".event.tag-wanted"
+)
+
+// forgeEnd is the part of a forge message the builder reads.
+type forgeEnd struct {
+	Kind       string `json:"kind"`
+	Repository string `json:"repository"`
+	Branch     string `json:"branch"`
+	Action     string `json:"action"`
+}
+
+// ended says whether the message ends a branch: merged, a pull closed, or branch-deleted.
+func (f forgeEnd) ended() bool {
+	switch f.Kind {
+	case delivery.ForgeMerged, forgeBranchDeleted:
+		return f.Branch != ""
+	case delivery.ForgePull:
+		return f.Action == delivery.PullClosed && f.Branch != ""
+	}
+	return false
+}
+
+// branchEnds hears the forge bridge's stream: every message wakes a floor whose bridge_tags was silent, and a branch's
+// end removes its tagged versions, acknowledged only once all are removed.
+type branchEnds struct {
+	acts     versions.Acts
+	findings *findings
+	tagAsks  func() jetstream.KeyValue
+	wake     func(ctx context.Context)
+	logf     func(string, ...any)
+	now      func() time.Time
+}
+
+func (h *branchEnds) heard(ctx context.Context, m jetstream.Msg) {
+	if h.wake != nil {
+		h.wake(ctx)
+	}
+	var f forgeEnd
+	if err := json.Unmarshal(m.Data(), &f); err != nil || !f.ended() {
+		h.ack(m)
+		return
+	}
+	end, err := h.acts.BranchEnded(ctx, f.Repository, f.Branch)
+	if err != nil {
+		h.logf("the end of %s %s: the versions cannot be read, heard again: %v", f.Repository, f.Branch, err)
+		h.again(m)
+		return
+	}
+	id := f.Repository + "/" + f.Branch
+	if end.Done {
+		h.findings.clear(ctx, versions.RemovalNotDone, health.ScopeModule, id)
+		if kv := h.tagAsks(); kv != nil {
+			if err := kv.Delete(ctx, versions.TagAskKey(f.Repository, f.Branch)); err != nil && !errors.Is(err, jetstream.ErrKeyNotFound) {
+				h.logf("the tag ask of %s %s stays in %s: %v", f.Repository, f.Branch, versions.TagAsksState, err)
+			}
+		}
+		h.ack(m)
+		return
+	}
+	since := h.now()
+	if md, err := m.Metadata(); err == nil {
+		since = md.Timestamp
+	}
+	if h.now().Sub(since) >= versions.RemovalFindingAfter {
+		h.findings.raise(ctx, finding{kind: versions.RemovalNotDone, scope: health.ScopeModule, id: id,
+			summary:     end.Finding(f.Repository, f.Branch, since),
+			headline:    "A branch's tagged versions are not removed",
+			explanation: "The branch ended, and the registry seats did not say removed for every version tagged for it within 15 minutes.",
+			resolved:    "Every seat said removed.",
+			needs:       "Look at the seats named: " + strings.Join(end.Seats(), ", ")})
+	}
+	h.logf("the end of %s %s: remove asked of %d tagged versions, heard again in a minute", f.Repository, f.Branch, len(end.Left))
+	h.again(m)
+}
+
+func (h *branchEnds) ack(m jetstream.Msg) {
+	if err := m.Ack(); err != nil {
+		h.logf("acknowledging %s: %v", m.Subject(), err)
+	}
+}
+
+// again leaves the message for the bus to give again in a minute: the retry is the bus's redelivery, not a timer here.
+func (h *branchEnds) again(m jetstream.Msg) {
+	if err := m.NakWithDelay(versions.RemoveAgainAfter); err != nil {
+		h.logf("leaving %s for the bus to give again: %v", m.Subject(), err)
+	}
+}
+
+// tagWanted takes the checker's tag-wanted in: written to tag-asks as builder_tag writes it, answered by its watch.
+func tagWanted(ctx context.Context, kv jetstream.KeyValue, m jetstream.Msg, by string, now time.Time, logf func(string, ...any)) {
+	if m.Subject() != tagWantedSubject {
+		_ = m.Ack() // the family's other events (the verdicts) are not the builder's
+		return
+	}
+	var t versions.TagWanted
+	err := json.Unmarshal(m.Data(), &t)
+	var key string
+	var value []byte
+	if err == nil {
+		key, value, err = versions.TagWantedAsk(t, by, now)
+	}
+	if err != nil {
+		logf("%s holds what is no tag-wanted, left: %v", m.Subject(), err)
+		_ = m.Ack()
+		return
+	}
+	if kv == nil {
+		logf("tag-wanted of %s %s is heard again: %s is not on the bus yet", t.Repository, t.Branch, versions.TagAsksState)
+		_ = m.NakWithDelay(versions.RemoveAgainAfter)
+		return
+	}
+	if _, err := kv.Put(ctx, key, value); err != nil {
+		logf("tag-wanted of %s %s is heard again: %v", t.Repository, t.Branch, err)
+		_ = m.Nak()
+		return
+	}
+	_ = m.Ack()
+}
+
+// tagsVia is build.Builder.Tags over the state tag-asks: the asks of the repository, read when a check's build is
+// looked at; none while the state is not bound.
+func tagsVia(kv func() jetstream.KeyValue, logf func(string, ...any)) build.TagOf {
+	return func(ctx context.Context, repository, head string) (string, bool) {
+		store := kv()
+		if store == nil {
+			return "", false
+		}
+		lister, err := store.ListKeysFiltered(ctx, versions.EscapeToken(repository)+".>")
+		if err != nil {
+			logf("the tag asks of %s cannot be read, so its check builds no tagged version: %v", repository, err)
+			return "", false
+		}
+		var asks []versions.TagAsk
+		for key := range lister.Keys() {
+			e, err := store.Get(ctx, key)
+			if err != nil {
+				continue
+			}
+			if t, err := versions.DecodeTagAsk(e.Value()); err == nil {
+				asks = append(asks, t)
+			}
+		}
+		return versions.TagFor(asks, repository, head)
+	}
+}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/bus.go

@@ -123,5 +123,6 @@ func (m manifestReader) Manifest(ctx context.Context, digest string) (catalogue.
 	if err != nil {
 		return catalogue.Manifest{}, err
 	}
-	return catalogue.ParseManifestForInputs([]byte(kept.JSON))
+	// Decoded, never judged (novox/hq ADR 0578 §3): what a build needs of it is read, a field it does not know set aside.
+	return catalogue.Decode([]byte(kept.JSON))
 }

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/findings.go

@@ -0,0 +1,174 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"time"
+
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/health"
+	"git.novox.be/novox/mesh-sdk/go/process"
+
+	"git.novox.be/novox/mesh-delivery/sdk/heard"
+
+	"mesh-delivery-builder/internal/versions"
+)
+
+// findingsBucket is the builder's findings (novox/hq ADR 0564 §2): what it sees wrong now, written at its raise and
+// deleted at its clear, which the condition keeper raises and clears.
+var findingsBucket = health.FindingsBucket(delivery.BuilderModule)
+
+// findings writes the builder's findings into its state, once bound; until then each is said in the log only.
+type findings struct {
+	kv   *process.AwaitedBucket
+	logf func(string, ...any)
+	now  func() time.Time
+	// store stands in for kv in a test.
+	store findingStore
+}
+
+// findingStore is the part of the findings bucket written.
+type findingStore interface {
+	Get(ctx context.Context, key string) (jetstream.KeyValueEntry, error)
+	Put(ctx context.Context, key string, value []byte) (uint64, error)
+	Delete(ctx context.Context, key string, opts ...jetstream.KVDeleteOpt) error
+}
+
+// finding is one of the builder's findings: its kind, what it is about, and its words.
+type finding struct {
+	kind, scope, id                                 string
+	summary, headline, explanation, resolved, needs string
+	severity                                        health.Severity
+}
+
+func (f *findings) bucket() findingStore {
+	switch {
+	case f == nil:
+		return nil
+	case f.store != nil:
+		return f.store
+	case f.kv == nil:
+		return nil
+	}
+	if kv := f.kv.KV(); kv != nil {
+		return kv
+	}
+	return nil
+}
+
+// BuildFailed is the finding of a failed trunk build (DLV-B7, design 25), about its module.
+const BuildFailed = "build-failed"
+
+// buildEnded raises the module's build-failed for a trunk build that failed and clears it at a later done one; a
+// candidate's build (its ref named) is the check's to say.
+func (f *findings) buildEnded(ctx context.Context, e delivery.BuildLogEntry) {
+	if e.Event != delivery.BuildEndedEvent || e.Ref != "" {
+		return
+	}
+	switch e.Outcome {
+	case delivery.BuildFailed:
+		f.raise(ctx, finding{kind: BuildFailed, scope: health.ScopeModule, id: e.Module,
+			summary:     "the trunk build of " + e.Module + " at " + e.FP + " (commit " + e.Commit + ") failed",
+			headline:    "A module's trunk build failed",
+			explanation: "The builder built " + e.Module + " from the trunk and the build failed, so its new version is not delivered.",
+			resolved:    "A later trunk build of " + e.Module + " is done.",
+			needs:       "builder_builds_since shows the build; builder_build_again builds it again."})
+	case delivery.BuildDone:
+		f.clear(ctx, BuildFailed, health.ScopeModule, e.Module)
+	}
+}
+
+// raise writes fd; it is written again only when its words changed, so the keeper's condition moves only then.
+func (f *findings) raise(ctx context.Context, fd finding) {
+	key := health.FindingKey(fd.scope, fd.id, fd.kind)
+	kv := f.bucket()
+	if kv == nil {
+		f.logf("finding %s (not written, %s is not on the bus yet): %s", key, findingsBucket, fd.summary)
+		return
+	}
+	if e, err := kv.Get(ctx, key); err == nil {
+		if old, err := health.DecodeFinding(e.Value()); err == nil && old.Summary == fd.summary {
+			return
+		}
+	}
+	at := f.now().UTC()
+	sev := fd.severity
+	if sev == "" {
+		sev = health.Warning
+	}
+	value, err := health.EncodeFinding(health.Finding{Key: key, Kind: fd.kind, Subject: health.Subject{Scope: fd.scope, ID: fd.id},
+		Severity: sev, Summary: fd.summary, Headline: fd.headline, Explanation: fd.explanation, Resolved: fd.resolved, Needs: fd.needs,
+		Evidence: []health.Evidence{{At: at, Said: fd.summary}}, Source: "builder." + fd.kind, Observer: delivery.BuilderModule, At: at})
+	if err == nil {
+		_, err = kv.Put(ctx, key, value)
+	}
+	if err != nil {
+		f.logf("the finding %s cannot be written: %v", key, err)
+	}
+}
+
+// clear deletes the finding of kind about scope and id; one not there is nothing to clear.
+func (f *findings) clear(ctx context.Context, kind, scope, id string) {
+	kv := f.bucket()
+	if kv == nil {
+		return
+	}
+	key := health.FindingKey(scope, id, kind)
+	if _, err := kv.Get(ctx, key); errors.Is(err, jetstream.ErrKeyNotFound) {
+		return
+	}
+	if err := kv.Delete(ctx, key); err != nil && !errors.Is(err, jetstream.ErrKeyNotFound) {
+		f.logf("the finding %s cannot be cleared: %v", key, err)
+	}
+}
+
+// notHeard is the writer of the builder's finding of a family it does not hear (heard.Writer, ADR 0615 §5): written into
+// its findings once bound, said in the log until then.
+func (f *findings) notHeard(ctx context.Context) heard.Writer {
+	on := func(do func(findingStore)) {
+		switch {
+		case f.store != nil:
+			do(f.store)
+		case f.kv != nil:
+			f.kv.Ready(func(kv jetstream.KeyValue) { do(kv) })
+		}
+	}
+	return heard.Writer{Observer: delivery.BuilderModule, Logf: f.logf, Now: f.now,
+		Put: func(key string, value []byte) error {
+			on(func(kv findingStore) {
+				if _, err := kv.Put(ctx, key, value); err != nil {
+					f.logf("the finding %s cannot be written: %v", key, err)
+				}
+			})
+			return nil
+		},
+		Delete: func(key string) error {
+			on(func(kv findingStore) {
+				if _, err := kv.Get(ctx, key); err != nil {
+					return // none stands
+				}
+				if err := kv.Delete(ctx, key); err != nil {
+					f.logf("the finding %s cannot be cleared: %v", key, err)
+				}
+			})
+			return nil
+		}}
+}
+
+// floorSaid is the floor finding (design 51 *Health and conditions*: a floor source silent): raised for a name waiting on
+// its floor, about that name, cleared once all three sources answered.
+func (f *findings) floorSaid(ctx context.Context) func(versions.FloorWait, bool) {
+	return func(w versions.FloorWait, raised bool) {
+		if !raised {
+			f.clear(ctx, versions.FloorSilent, health.ScopeModule, w.Name)
+			return
+		}
+		f.raise(ctx, finding{kind: versions.FloorSilent, scope: health.ScopeModule, id: w.Name, summary: w.Finding(),
+			headline:    "A version's floor is not known",
+			explanation: "The builder numbers a name only once its registry seat, the forge bridge's tags and the indexer's requirements all answered; one of them did not.",
+			resolved:    "All three answered.",
+			needs:       "builder_floor_waits names the silent source; builder_floor_again asks again by hand."})
+	}
+}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/gone_integration_test.go

@@ -12,6 +12,7 @@ import (
 	"github.com/nats-io/nats.go"
 	"github.com/nats-io/nats.go/jetstream"
 
+	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
 )
 
@@ -19,7 +20,7 @@ import (
 // (novox/hq issue 1937): on 2026-10-24 the store's 03:30 collection deleted the bare blobs of three done keys the
 // controller had never taken in, and the builder kept them done.
 
-// heldVerb answers the controller seat's verb held on the bus, as the serving controller does: {result: {output, ok,
+// heldVerb answers the seat mesh-artifact-sweep's verb held on the bus, as its holder does: {result: {output, ok,
 // answer}}; a reference is gone while gone says so.
 type heldVerb struct {
 	mu    sync.Mutex
@@ -29,7 +30,7 @@ type heldVerb struct {
 
 func (h *heldVerb) serve(t *testing.T, b *bed) {
 	t.Helper()
-	sub, err := b.js.Conn().Subscribe("mesh.seat.mesh-controller.call.held.>", func(m *nats.Msg) {
+	sub, err := b.js.Conn().Subscribe("mesh.seat."+catalogue.ArtifactSweepSeat+".call.held.>", func(m *nats.Msg) {
 		var args struct {
 			References []string `json:"references"`
 		}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/integration_test.go

@@ -9,9 +9,10 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io"
+	"maps"
 	"os"
 	"path/filepath"
+	"slices"
 	"strings"
 	"sync"
 	"sync/atomic"
@@ -22,11 +23,20 @@ import (
 	"github.com/nats-io/nats.go"
 	"github.com/nats-io/nats.go/jetstream"
 
+	// The build runner the build modules pull and run asks with: mesh-build-go's own package (novox/hq ADR 0593 §1),
+	// another repository's, by its published version, so the builder is tested against the real pulling code.
+	runner "git.novox.be/novox/mesh-catalog/modules/mesh-build-go/buildstep"
+	"git.novox.be/novox/mesh-contracts/go/seats/gopackageregistry"
+	"git.novox.be/novox/mesh-contracts/go/seats/ociartifactregistry"
 	"git.novox.be/novox/mesh-sdk/go/buildstep"
+	"git.novox.be/novox/mesh-sdk/go/buscompose"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/health"
 	"git.novox.be/novox/mesh-sdk/go/process"
+	"git.novox.be/novox/mesh-sdk/go/views/viewstest"
 
 	"mesh-delivery-builder/internal/build"
+	"mesh-delivery-builder/internal/versions"
 )
 
 // busConf is the shape of the composed accounts file (mesh-controller internal/broker): one account with JetStream, the
@@ -52,7 +62,7 @@ const (
 )
 
 // fakeBuildModules are the build modules on the nodes as the real ones run since R4g (ADR 0525; issue 1887 A4): each pulls
-// its build seat's asks on its nodes (buildstep.Puller over the seat's workers) and runs an ask's job with step bodies that
+// its build seat's asks on its nodes (runner.Puller over the seat's workers) and runs an ask's job with step bodies that
 // answer as the real tools do, ending the step on <node>.<ask id> of its steps bucket.
 type fakeBuildModules struct {
 	js        jetstream.JetStream
@@ -67,14 +77,17 @@ type fakeBuildModules struct {
 	// closed, while set, keeps every node's capacity at 0: no ask is pulled until open is called (a test of the asks
 	// waiting in their streams).
 	closed  atomic.Bool
-	pullers []*buildstep.Puller
+	pullers []*runner.Puller
+	// hang, while it holds a channel, keeps every build step running until the channel is closed: a step that never ends,
+	// so the builder's step bound runs out (design 51's round-2 case).
+	hang atomic.Pointer[chan struct{}]
 }
 
 // open lets the nodes pull again and wakes their pullers.
 func (f *fakeBuildModules) open() {
 	f.closed.Store(false)
 	f.mu.Lock()
-	ps := append([]*buildstep.Puller(nil), f.pullers...)
+	ps := append([]*runner.Puller(nil), f.pullers...)
 	f.mu.Unlock()
 	for _, p := range ps {
 		p.Wake()
@@ -106,6 +119,12 @@ func (f *fakeBuildModules) step(module, name string, args map[string]any) (any,
 		f.builds = append(f.builds, args)
 	}
 	f.mu.Unlock()
+	if h := f.hang.Load(); h != nil && name == "build" {
+		select {
+		case <-*h:
+		case <-f.ctx.Done():
+		}
+	}
 	switch {
 	case name == "fetch":
 		merge := ""
@@ -138,26 +157,26 @@ func (f *fakeBuildModules) serve(t *testing.T, module string, nodes ...string) {
 		t.Fatal(err)
 	}
 	language := strings.TrimPrefix(module, "mesh-build-")
-	if err := buildstep.DeclareAskWorkers(f.ctx, f.js, language, 30*time.Second); err != nil {
+	if err := runner.DeclareAskWorkers(f.ctx, f.js, language, 30*time.Second); err != nil {
 		t.Fatal(err)
 	}
 	put := func(key string, value any) (uint64, error) {
 		raw, _ := value.(json.RawMessage)
 		return kv.Put(f.ctx, key, raw)
 	}
-	call := func(name string) buildstep.StepFunc {
+	call := func(name string) runner.StepFunc {
 		return func(ctx context.Context, args map[string]any) (any, error) { return f.step(module, name, args) }
 	}
-	steps := buildstep.AskSteps{Fetch: call("fetch"), Build: call("build"), Copy: call("copy")}
+	steps := runner.AskSteps{Fetch: call("fetch"), Build: call("build"), Copy: call("copy")}
 	for _, node := range nodes {
-		p := &buildstep.Puller{Source: &buildstep.JetStreamAsks{JS: f.js, Language: language}, Language: language, Node: node, Put: put,
+		p := &runner.Puller{Source: &runner.JetStreamAsks{JS: f.js, Language: language}, Language: language, Node: node, Put: put,
 			Capacity: func() int {
 				if f.closed.Load() {
 					return 0
 				}
 				return 2
 			}, PullWait: 200 * time.Millisecond,
-			Run: func(ctx context.Context, a delivery.StepAsk) (any, error) { return buildstep.RunAsk(ctx, steps, a) }}
+			Run: func(ctx context.Context, a delivery.StepAsk) (any, error) { return runner.RunAsk(ctx, steps, a) }}
 		f.mu.Lock()
 		f.pullers = append(f.pullers, p)
 		f.mu.Unlock()
@@ -191,7 +210,11 @@ type bed struct {
 	builds     jetstream.KeyValue
 	tools      map[string]jetstream.KeyValue
 	instances  jetstream.KeyValue
-	stop       func() // stops the builder started last
+	tagAsks    jetstream.KeyValue
+	tagBounds  jetstream.KeyValue
+	packages   jetstream.KeyValue // the indexer's packages, served by its read tool and views family
+	out        *saidLog           // the builder's process log, every instance's
+	stop       func()             // stops the builder started last
 	fake       *fakeBuildModules
 	srvURL     string
 	dir        string
@@ -266,8 +289,29 @@ func startBedWith(t *testing.T, closed bool) *bed {
 	b.candidates = mk(delivery.CandidatesBucket, delivery.CandidatesHistory)
 	b.source = mk(delivery.SourceBucket, delivery.SourceHistory)
 	mk(delivery.ManifestsBucket, delivery.ManifestsHistory)
+	// The indexer and the assigner as the owners of the states the builder follows: their read tools and views families
+	// (ADR 0615, DLV-M1); n1 and n2 each have their durable consumer.
+	readers := []string{"n1_" + delivery.BuilderModule, "n2_" + delivery.BuilderModule}
+	for _, st := range []string{modulesState, manifestsState, candidatesState} {
+		viewstest.Serve(t, ctx, js, ctl, delivery.IndexerModule, st, delivery.IndexerModule+".indexer_read_"+st, indexerViews, readers...)
+	}
+	b.packages = viewstest.Serve(t, ctx, js, ctl, delivery.IndexerModule, delivery.PackagesState, delivery.IndexerModule+".indexer_read_packages", indexerViews, readers...)
+	viewstest.Serve(t, ctx, js, ctl, delivery.AssignerModule, delivery.PlacementState, delivery.AssignerModule+".assigner_read_placement", assignerViews, readers...)
 	b.builds = mk(delivery.BuilderBuildsBucket, delivery.BuilderBuildsHistory)
 	b.instances = mk(instancesBucket, 1)
+	// The tag asks and their bounds (design 51 *Tagged versions*): the bounds declared key-ttl, so an ended bound leaves the
+	// bus's marker a watch hears.
+	b.tagAsks = mk(versions.TagAsksBucket, 1)
+	if b.tagBounds, err = js.CreateKeyValue(ctx, jetstream.KeyValueConfig{Bucket: versions.TagAskBoundsBucket, History: 1, LimitMarkerTTL: time.Minute}); err != nil {
+		t.Fatal(err)
+	}
+	b.out = &saidLog{}
+	// The builder's module log, as the runtime raises it (ADR 0297): its stream on the log's subjects.
+	logStream := buscompose.LogStreamName(delivery.BuilderModule, delivery.BuilderLog)
+	if _, err := js.CreateStream(ctx, jetstream.StreamConfig{Name: logStream, Subjects: []string{buscompose.LogSubject(delivery.BuilderModule, delivery.BuilderLog) + ".>"},
+		AllowDirect: true}); err != nil {
+		t.Fatal(err)
+	}
 	b.fake = &fakeBuildModules{js: js, ctx: ctx, calls: map[string]int{}}
 	b.fake.closed.Store(closed)
 	b.fake.serve(t, "mesh-build-go", "n1", "n2")
@@ -280,6 +324,29 @@ func startBedWith(t *testing.T, closed bool) *bed {
 	return b
 }
 
+// logged is every entry of module's key in the builder's log, read through process.Conn.ReadLog on the controller's user.
+func (b *bed) logged(t *testing.T, module string) []delivery.BuildLogEntry {
+	t.Helper()
+	conn, err := process.Connect(process.Account{URL: b.srvURL, Module: "mesh-delivery-view", User: "ctl", Password: "pw"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer conn.Close()
+	entries, err := conn.ReadLog(delivery.BuilderModule, delivery.BuilderLog).Since(time.Unix(0, 0), module)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var out []delivery.BuildLogEntry
+	for _, le := range entries {
+		e, err := delivery.DecodeBuildLogEntry(le.Value)
+		if err != nil {
+			t.Fatal(err)
+		}
+		out = append(out, e)
+	}
+	return out
+}
+
 // report writes a node's toolchains key of a build module and says so on the module's stream, as the module does.
 func (b *bed) report(t *testing.T, module, node, language, version, recipe string) {
 	t.Helper()
@@ -298,15 +365,24 @@ func (b *bed) report(t *testing.T, module, node, language, version, recipe strin
 
 // module writes modules.<name> as the indexer does for a module with a new-form fingerprint, and its manifest by digest.
 func (b *bed) module(t *testing.T, name, fixture, path string) string {
-	return b.moduleWith(t, name, fixture, path, map[string]delivery.ToolchainUsed{"go": {Version: "go1.27.1", Recipe: "1"}, "typescript": {Version: "tsc5", Recipe: "1"}})
+	return b.moduleWith(t, name, fixture, path, bothToolchains)
 }
 
+// bothToolchains are the toolchains the bed's nodes report, as a module's fingerprint names them.
+var bothToolchains = map[string]delivery.ToolchainUsed{"go": {Version: "go1.27.1", Recipe: "1"}, "typescript": {Version: "tsc5", Recipe: "1"}}
+
 // moduleWith is module with the toolchains its fingerprint was computed with.
 func (b *bed) moduleWith(t *testing.T, name, fixture, path string, toolchains map[string]delivery.ToolchainUsed) string {
 	return b.moduleCommit(t, name, fixture, path, toolchains, commit)
 }
 
 func (b *bed) moduleCommit(t *testing.T, name, fixture, path string, toolchains map[string]delivery.ToolchainUsed, at string) string {
+	t.Helper()
+	return b.moduleFP(t, name, fixture, path, toolchains, at, fp, 0)
+}
+
+// moduleFP is moduleCommit with the new-form fingerprint fp2 and the source revision src of its merge (0: none).
+func (b *bed) moduleFP(t *testing.T, name, fixture, path string, toolchains map[string]delivery.ToolchainUsed, at, fp2 string, src uint64) string {
 	t.Helper()
 	raw, err := os.ReadFile(filepath.Join("testdata", fixture))
 	if err != nil {
@@ -324,8 +400,8 @@ func (b *bed) moduleCommit(t *testing.T, name, fixture, path string, toolchains
 	if _, err := manifests.Put(b.ctx, digest, mv); err != nil {
 		t.Fatal(err)
 	}
-	data, err := delivery.EncodeModule(delivery.Module{Repository: "novox/mesh-catalog", Commit: at, FP: "src1:" + strings.Repeat("f", 64), FP2: fp,
-		Manifest: digest, Path: path, Toolchains: toolchains})
+	data, err := delivery.EncodeModule(delivery.Module{Repository: "novox/mesh-catalog", Commit: at, FP: "src1:" + strings.Repeat("f", 64), FP2: fp2,
+		Manifest: digest, Path: path, Toolchains: toolchains, Src: src})
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -356,16 +432,58 @@ func (b *bed) start(t *testing.T, node string, env map[string]string) {
 	}
 	runCtx, stop := context.WithCancel(b.ctx)
 	done := make(chan error, 1)
-	go func() { done <- run(runCtx, func(k string) string { return e[k] }, io.Discard) }()
+	go func() { done <- run(runCtx, func(k string) string { return e[k] }, b.out) }()
 	var once sync.Once
 	b.stop = func() { once.Do(func() { stop(); <-done }) }
 	t.Cleanup(b.stop)
 }
 
+// saidLog is the builder's process log as its instances write it.
+type saidLog struct {
+	mu  sync.Mutex
+	buf strings.Builder
+}
+
+func (l *saidLog) Write(p []byte) (int, error) {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	return l.buf.Write(p)
+}
+
+// awaitSaid reads the process log until it holds want, within 20 s, and answers the line.
+func (b *bed) awaitSaid(t *testing.T, want string) string {
+	t.Helper()
+	deadline := time.Now().Add(20 * time.Second)
+	for {
+		b.out.mu.Lock()
+		all := b.out.buf.String()
+		b.out.mu.Unlock()
+		for _, line := range strings.Split(all, "\n") {
+			if strings.Contains(line, want) {
+				return line
+			}
+		}
+		if time.Now().After(deadline) {
+			t.Fatalf("the builder never said %q; it said:\n%s", want, all)
+		}
+		select {
+		case <-b.ctx.Done():
+			t.Fatal(b.ctx.Err())
+		case <-time.After(50 * time.Millisecond):
+		}
+	}
+}
+
 // await reads the build key until pred holds of it, within 20 s.
 func (b *bed) await(t *testing.T, module string, pred func(delivery.BuilderBuild) bool) delivery.BuilderBuild {
 	t.Helper()
-	key, err := delivery.BuilderBuildKey(module, fp)
+	return b.awaitFP(t, module, fp, pred)
+}
+
+// awaitFP is await of the build key of fingerprint at.
+func (b *bed) awaitFP(t *testing.T, module, at string, pred func(delivery.BuilderBuild) bool) delivery.BuilderBuild {
+	t.Helper()
+	key, err := delivery.BuilderBuildKey(module, at)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -392,9 +510,31 @@ func isState(state string) func(delivery.BuilderBuild) bool {
 // the digests of both bundles, both build modules' toolchains, after a fetch and a build on one node (ADR 0478 clause 4).
 func TestBuilderMakesADoneKeyWithTheDigests(t *testing.T) { // 1607/AC7
 	b := startBed(t)
-	digest := b.module(t, "netcheck", "catalogue-a67f0196-netcheck.module.json", "modules/netcheck")
-	b.start(t, "n1", nil)
+	// DLV-B10 (design 51, round 2): the builder's versions, findings and the floor's three sources are on the bus; the seat
+	// answers 0.1.4, so netcheck's bundles are numbered from 0.1.5. Two merges close together, the first replaced before
+	// its claim: the second is numbered at once, and the first never.
+	reg := b.registry(t, "n1", "0.1.4")
+	const netcheck = "catalogue-a67f0196-netcheck.module.json"
+	first := "src2:" + strings.Repeat("1", 64)
+	b.moduleFP(t, "netcheck", netcheck, "modules/netcheck", bothToolchains, commit, first, 1)
+	digest := b.moduleFP(t, "netcheck", netcheck, "modules/netcheck", bothToolchains, commit, fp, 2)
+	// DLV-B6: a tag ask kept and never numbered (no check builds its head) is narrated once its bound ends on the bus, with
+	// what it waits on, and its bound is written again; no timer runs in the builder.
+	key, ask, err := versions.NewTagAsk("novox/mesh-sdk", "feat/x", "abc", "a group member's check", "me@shanks", time.Now())
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err := b.tagAsks.Put(b.ctx, key, ask); err != nil {
+		t.Fatal(err)
+	}
+	b.start(t, "n1", map[string]string{"MESH_BUILDER_TAG_ASK_BOUND": "1s", "MESH_BUILDER_STEP_BOUND": "1s"})
 	v := b.await(t, "netcheck", isState(delivery.BuildDone))
+	for _, a := range []string{"tools-go", "tools-typescript"} {
+		es := reg.of(t, "netcheck/"+a)
+		if len(es) != 1 || es[0].Version != "0.1.5" || es[0].Fingerprint != fp || es[0].State != versions.Numbered || es[0].Digest != digestOf(a) {
+			t.Errorf("versions of netcheck/%s = %+v, want the second merge numbered 0.1.5 at once with its digest, the first never", a, es)
+		}
+	}
 	if v.By != "n1.mesh-delivery-builder" || v.Manifest != digest || len(v.Artifacts) != 2 {
 		t.Fatalf("build = %+v", v)
 	}
@@ -406,39 +546,193 @@ func TestBuilderMakesADoneKeyWithTheDigests(t *testing.T) { // 1607/AC7
 	if v.Toolchains["go"].Version != "go1.27.1" || v.Toolchains["typescript"].Version != "tsc5" {
 		t.Errorf("toolchains = %+v", v.Toolchains)
 	}
+	// ADR 0618 §1: the done key names the reference forms it is written in.
+	if len(v.Needs) != 1 || v.Needs[0] != "form:artifact-store" {
+		t.Errorf("needs = %v, want the first form", v.Needs)
+	}
+	// 1955/L7 (ADR 0571 §1): the build's start and end are in the module log build-log under the module's key, read as a
+	// reader with the log's read reads them, the end naming the manifest and what was made.
+	// DLV-B10: between them the build log holds the build's narrations (build.said), each version numbered, and why.
+	var ended []delivery.BuildLogEntry
+	for _, e := range b.logged(t, "netcheck") {
+		if e.Event != delivery.BuildSaidEvent {
+			ended = append(ended, e)
+		} else if e.Why != versions.SaidNumbered || !strings.Contains(e.Line, "numbered 0.1.5") || e.FP != fp {
+			t.Errorf("said = %+v, want netcheck's versions numbered", e)
+		}
+	}
+	if len(ended) != 2 || ended[0].Event != delivery.BuildStartedEvent || ended[1].Event != delivery.BuildEndedEvent ||
+		ended[1].Manifest != digest || len(ended[1].Made) != 2 || ended[1].Node != "n1" {
+		t.Errorf("logged = %+v, want the start and the end of netcheck's build", ended)
+	}
 	for tool, want := range map[string]int{"mesh-build-go.build_go_fetch": 1, "mesh-build-go.build_go_build": 1, "mesh-build-node.build_node_fetch": 1, "mesh-build-node.build_node_build": 1} {
 		if got := b.fake.count(tool); got != want {
 			t.Errorf("%s called %d times, want %d (on one node, ADR 0478 clause 4)", tool, got, want)
 		}
 	}
+	said := b.awaitSaid(t, "the tag ask of novox/mesh-sdk feat/x at abc (feat-x) is not answered after")
+	if !strings.Contains(said, "the check's build of abc is not claimed yet") {
+		t.Errorf("the narration = %q, want what the ask waits on", said)
+	}
+	// And in the build log, under the builder's own key (the ruling of 13:17: build.said).
+	if !slices.ContainsFunc(b.logged(t, delivery.BuilderModule), func(e delivery.BuildLogEntry) bool {
+		return e.Event == delivery.BuildSaidEvent && e.Why == versions.SaidUnanswered && e.FP == key && e.Commit == "abc" &&
+			strings.Contains(e.Line, "the check's build of abc is not claimed yet")
+	}) {
+		t.Errorf("the build log of %s = %+v, want the unanswered tag ask said", delivery.BuilderModule, b.logged(t, delivery.BuilderModule))
+	}
+	if e, err := b.tagAsks.Get(b.ctx, key); err != nil {
+		t.Fatal(err)
+	} else if a, _ := versions.DecodeTagAsk(e.Value()); a.Answered.IsZero() || !a.Unanswered() {
+		t.Errorf("the tag ask = %+v, want kept and answered, no version yet", a)
+	}
+	for deadline := time.Now().Add(10 * time.Second); ; time.Sleep(50 * time.Millisecond) {
+		if _, err := b.tagBounds.Get(b.ctx, key); err == nil {
+			break
+		} else if time.Now().After(deadline) {
+			t.Fatalf("the bound is not written again after its narration: %v", err)
+		}
+	}
+	// Design 32, ADR 0615 §1: a package's name the indexer writes later reaches the builder by its packages' views family
+	// (never their bucket), and looks at the module again; the done bundles are kept, not numbered twice.
+	if _, err := b.packages.Put(b.ctx, "netcheck.0.1", []byte(`{"v":1,"name":"netcheck","package":"netcheck/lib","series":"0.1"}`)); err != nil {
+		t.Fatal(err)
+	}
+	b.awaitSaid(t, "names a package of netcheck")
+	if got := reg.numberedOf("netcheck/tools-go"); len(got) != 1 || got[0] != "0.1.5" {
+		t.Errorf("version.numbered of netcheck/tools-go = %v, want 0.1.5 once", got)
+	}
+	// DLV-B10: builder_publish_again after a published takes a new number, and says it numbered.
+	for _, a := range []string{"tools-go", "tools-typescript"} {
+		reg.published(t, "netcheck/"+a, "0.1.5", digestOf(a))
+	}
+	reg.awaitOf(t, "netcheck/tools-go", func(es []versions.Entry) bool { return len(es) == 1 && es[0].State == versions.Published })
+	key, again, err := build.NewPublishAgain("netcheck/tools-go", fp, "the holder lost it", "me@shanks", time.Now())
+	if err != nil {
+		t.Fatal(err)
+	}
+	if a := reg.answered(t, key, again); a.Refused || a.Do != versions.AgainRenumber || a.Version != "0.1.6" {
+		t.Errorf("builder_publish_again = %+v, want a new number, 0.1.6", a)
+	}
+	// Running-testing note (review round 1): two claims never get one number on the bus's own compare-and-set, as
+	// the builder's state versions keeps them: eight claims of one name at once, eight versions.
+	store := versions.Versions{Store: awaitedVersions{process.AwaitBucket(b.ctx, b.js, nil, versions.Bucket, "", t.Logf)}}
+	numbers := make(chan string, 8)
+	var claims sync.WaitGroup
+	for i := range 8 {
+		claims.Go(func() {
+			d, _, err := store.Number(b.ctx, versions.Claim{Name: "netcheck/race", Kind: versions.KindBundle, Fingerprint: fmt.Sprintf("f%d", i)})
+			if err != nil {
+				t.Error(err)
+			}
+			numbers <- d.Version
+		})
+	}
+	claims.Wait()
+	close(numbers)
+	got := map[string]bool{}
+	for v := range numbers {
+		got[v] = true
+	}
+	if len(got) != 8 {
+		t.Errorf("eight claims of one name at once were numbered %v, want eight versions", slices.Sorted(maps.Keys(got)))
+	}
+	if got := reg.numberedOf("netcheck/tools-go"); len(got) != 2 || got[1] != "0.1.6" {
+		t.Errorf("version.numbered of netcheck/tools-go = %v, want 0.1.6 said after 0.1.5", got)
+	}
+	// DLV-B10: a build module's bound running out fails the trunk build, which is the builder's finding build-failed; the
+	// fingerprint built again keeps its number, said with why, and its done build clears the finding.
+	release := make(chan struct{})
+	b.fake.hang.Store(&release)
+	third := "src2:" + strings.Repeat("4", 64)
+	b.moduleFP(t, "netcheck", netcheck, "modules/netcheck", bothToolchains, commit, third, 3)
+	if f := b.awaitFP(t, "netcheck", third, isState(delivery.BuildFailed)); !strings.Contains(f.Error, "did not end within") {
+		t.Errorf("the failed build = %+v, want its bound run out", f)
+	}
+	failed := health.FindingKey(health.ScopeModule, "netcheck", BuildFailed)
+	reg.awaitFinding(t, failed, true)
+	b.fake.hang.Store(nil)
+	close(release)
+	b.moduleFP(t, "netcheck", netcheck, "modules/netcheck", bothToolchains, commit, third, 3) // the indexer writes it again
+	b.awaitFP(t, "netcheck", third, isState(delivery.BuildDone))
+	b.awaitSaid(t, "kept: fingerprint "+third+" is numbered under it")
+	if !slices.ContainsFunc(b.logged(t, "netcheck"), func(e delivery.BuildLogEntry) bool {
+		return e.Event == delivery.BuildSaidEvent && e.Why == versions.SaidKept && e.FP == third && strings.Contains(e.Line, "kept: fingerprint "+third)
+	}) {
+		t.Errorf("the build log of netcheck says no version kept at %s", third)
+	}
+	reg.awaitFinding(t, failed, false)
+	// DLV-B4: the seats' refused and removed, heard on the builder's durable consumer, move a numbered version: a retention
+	// removal turns the entry removed with its reason, a refusal refused with the holder's reason and the bytes it refused.
+	reg.outcome(t, ociartifactregistry.SubjectRemoved, versions.Outcome{Name: "netcheck/tools-typescript", Version: "0.1.5", Kind: "bundle", Holder: "distribution", Reason: "retention"})
+	reg.outcome(t, ociartifactregistry.SubjectRefused, versions.Outcome{Name: "netcheck/tools-go", Version: "0.1.6", Digest: digestOf("other"), Kind: "bundle", Holder: "distribution", Reason: "the cap"})
+	reg.awaitOf(t, "netcheck/tools-typescript", func(es []versions.Entry) bool {
+		return slices.ContainsFunc(es, func(e versions.Entry) bool {
+			return e.Version == "0.1.5" && e.State == versions.Removed && e.Reason == "retention"
+		})
+	})
+	reg.awaitOf(t, "netcheck/tools-go", func(es []versions.Entry) bool {
+		return slices.ContainsFunc(es, func(e versions.Entry) bool {
+			return e.Version == "0.1.6" && e.State == versions.Refused && e.Reason == "the cap" && e.RefusedDigest == digestOf("other")
+		})
+	})
+	// DLV-B6: a branch's end (the forge bridge's merged) asks the seat to remove each version tagged for it, the reason
+	// tag-gone, and the seat's removed turns it removed.
+	tagged := versions.Entry{Name: "mesh-sdk/go", Kind: versions.KindPackage, Series: "0.1", Version: "0.1.15-feat-x.1", Tag: "feat-x", Module: "mesh-sdk",
+		Fingerprint: "src2:" + strings.Repeat("5", 64), Repository: "novox/mesh-sdk", Seat: gopackageregistry.Seat, State: versions.Published, At: time.Now().UTC()}
+	raw, _ := json.Marshal(tagged)
+	if _, err := reg.versions.Put(b.ctx, versions.Key(tagged.Name, tagged.Version), raw); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := b.js.Publish(b.ctx, process.ModuleStreamSubject(delivery.ForgeBridgeModule, "forge"),
+		[]byte(`{"kind":"`+delivery.ForgeMerged+`","repository":"novox/mesh-sdk","branch":"feat/x"}`)); err != nil {
+		t.Fatal(err)
+	}
+	for deadline := time.Now().Add(20 * time.Second); ; time.Sleep(50 * time.Millisecond) {
+		reg.mu.Lock()
+		asked := slices.ContainsFunc(reg.removes, func(a map[string]any) bool {
+			return a["name"] == tagged.Name && a["version"] == tagged.Version && a["reason"] == "tag-gone"
+		})
+		reg.mu.Unlock()
+		if asked {
+			break
+		}
+		if time.Now().After(deadline) {
+			t.Fatalf("the seat's remove of %s@%s was not asked at the branch's end: %v", tagged.Name, tagged.Version, reg.removes)
+		}
+	}
+	reg.outcome(t, gopackageregistry.SubjectRemoved, versions.Outcome{Name: tagged.Name, Version: tagged.Version, Kind: versions.KindPackage, Holder: "gitea", Reason: "tag-gone"})
+	reg.awaitOf(t, tagged.Name, func(es []versions.Entry) bool { return len(es) == 1 && es[0].State == versions.Removed })
 }
 
-// TestTwoBuilderInstancesStartingTogetherEndWithOneDoneKey: two builders on two nodes start together on one module key of an
-// archive only (no toolchain named, as the indexer writes it); the second takes over the key the first holds building
-// (ADR 0478 clause 6), and the key ends done, written once.
-func TestTwoBuilderInstancesStartingTogetherEndWithOneDoneKey(t *testing.T) { // 1607/AC7
-	b := startBed(t)
-	b.archive(t, "ca-trust", "modules/ca-trust", commit)
-	b.start(t, "n1", nil)
-	b.start(t, "n2", nil)
-	v := b.await(t, "ca-trust", isState(delivery.BuildDone))
-	if len(v.Artifacts) != 1 || v.Artifacts[0].Kind != "archive" || v.Artifacts[0].Digest != digestOf("files") {
-		t.Fatalf("build = %+v, want the archive's digest", v)
-	}
-	if n := b.fake.count("mesh-build-go.build_go_build"); n < 1 { // each instance that built, on one node
-		t.Errorf("build_go_build was called %d times, want one for each instance that built", n)
-	}
-}
-
-// TestAnArchiveOnlyModuleNamingNoToolchainIsBuilt: the indexer gives an archive no language, so modules.ca-trust has no
-// toolchains; the builder builds it on the build module's nodes all the same (review round 4).
-func TestAnArchiveOnlyModuleNamingNoToolchainIsBuilt(t *testing.T) {
-	b := startBed(t)
-	b.archive(t, "ca-trust", "modules/ca-trust", commit)
-	b.start(t, "n1", nil)
-	v := b.await(t, "ca-trust", isState(delivery.BuildDone))
-	if len(v.Toolchains) != 0 || len(v.Artifacts) != 1 || strings.HasPrefix(v.Step, "one node (") {
-		t.Errorf("build = %+v, want done naming no toolchain", v)
+// TestAnArchiveOnlyModuleAndARootModuleAreBuilt: the indexer gives an archive no language, so modules.ca-trust has no
+// toolchains; the builder builds it on the build module's nodes all the same (review round 4). A module whose path is "."
+// is given to the build tools as it is (1615/AC4). Two builders on two nodes start together on the archive's key: the
+// second takes over the key the first holds building (ADR 0478 clause 6), and the key ends done, written once (1607/AC7).
+// One table: three tests were merged, to pay for the enrolment's and to bring mesh-delivery's count down (DLV-B8).
+func TestAnArchiveOnlyModuleAndARootModuleAreBuilt(t *testing.T) {
+	for _, c := range []struct {
+		name, path string
+		two        bool
+	}{{"no toolchain", "modules/ca-trust", false}, {"root", delivery.RootPath, false}, {"two instances together", "modules/ca-trust", true}} {
+		t.Run(c.name, func(t *testing.T) {
+			b := startBed(t)
+			b.archive(t, "ca-trust", c.path, commit)
+			b.start(t, "n1", nil)
+			if c.two {
+				b.start(t, "n2", nil)
+			}
+			v := b.await(t, "ca-trust", isState(delivery.BuildDone))
+			if c.name == "no toolchain" && (len(v.Toolchains) != 0 || len(v.Artifacts) != 1 || strings.HasPrefix(v.Step, "one node (")) {
+				t.Errorf("build = %+v, want done naming no toolchain", v)
+			}
+			if c.two && (len(v.Artifacts) != 1 || v.Artifacts[0].Kind != "archive" || v.Artifacts[0].Digest != digestOf("files")) {
+				t.Errorf("build = %+v, want the archive's digest", v)
+			}
+			if n := b.fake.count("mesh-build-go.build_go_build"); c.two && n < 1 { // each instance that built, on one node
+				t.Errorf("build_go_build was called %d times, want one for each instance that built", n)
+			}
+		})
 	}
 }
 
@@ -493,14 +787,6 @@ func TestAToolchainChangeDoesNotBuildTheOldFingerprint(t *testing.T) { // 1615/A
 	}
 }
 
-// TestARootModuleIsBuilt: a module whose path is "." is given to the build tools as it is.
-func TestARootModuleIsBuilt(t *testing.T) { // 1615/AC4
-	b := startBed(t)
-	b.archive(t, "ca-trust", delivery.RootPath, commit)
-	b.start(t, "n1", nil)
-	b.await(t, "ca-trust", isState(delivery.BuildDone))
-}
-
 func mustKey(t *testing.T, module string) string {
 	k, err := delivery.BuilderBuildKey(module, fp)
 	if err != nil {
@@ -754,7 +1040,12 @@ func TestTheBuilderAsksTheBuildSeatsAndCallsNoNode(t *testing.T) {
 	}
 	defer sub.Close()
 	var calls atomic.Int64
-	s, err := sub.Subscribe("mesh.mod.*.call.>", func(*nats.Msg) { calls.Add(1) })
+	// A build module's tool, never the owners' read tools the builder's first views ask (DLV-M1).
+	s, err := sub.Subscribe("mesh.mod.*.call.>", func(m *nats.Msg) {
+		if strings.HasPrefix(m.Subject, "mesh.mod.mesh-build-") {
+			calls.Add(1)
+		}
+	})
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -873,3 +1164,184 @@ func TestARestartedBuilderPutsNoSecondAsk(t *testing.T) {
 		t.Errorf("done = %+v", done)
 	}
 }
+
+// registry is the part of the bed design 51's builder cases need: the builder's states versions, findings, floor-waits and
+// reasks, EVENTS with the seat oci-artifact-registry's outcomes and the builder's durable consumer of it, the builder's
+// own events kept, and the floor's three sources served on the bus as their holders answer through the tool runner
+// ({result}): the seat's versions, the forge bridge's bridge_tags and the indexer's indexer_requirements.
+type registry struct {
+	b                          *bed
+	versions, findings, reasks jetstream.KeyValue
+	mu                         sync.Mutex
+	numbered                   []delivery.VersionNumbered
+	removes                    []map[string]any
+}
+
+func (b *bed) registry(t *testing.T, node string, seatVersions ...string) *registry {
+	t.Helper()
+	r := &registry{b: b}
+	mk := func(name string) jetstream.KeyValue {
+		kv, err := b.js.CreateKeyValue(b.ctx, jetstream.KeyValueConfig{Bucket: name, History: 1})
+		if err != nil {
+			t.Fatal(err)
+		}
+		return kv
+	}
+	r.versions, r.findings, r.reasks = mk(versions.Bucket), mk(findingsBucket), mk(build.ReAsksBucket)
+	mk(versions.FloorWaitsBucket)
+	// EVENTS with two seats' outcomes, and the forge bridge's stream (a branch's end): each with the builder's durable consumer.
+	for stream, subjects := range map[string][]string{
+		eventsStream: {delivery.ArtifactsGoneSubject, ociartifactregistry.SubjectPublished, ociartifactregistry.SubjectRefused, ociartifactregistry.SubjectRemoved,
+			gopackageregistry.SubjectPublished, gopackageregistry.SubjectRefused, gopackageregistry.SubjectRemoved},
+		forgeStream: {process.ModuleStreamSubject(delivery.ForgeBridgeModule, ">")},
+	} {
+		if _, err := b.js.CreateStream(b.ctx, jetstream.StreamConfig{Name: stream, Subjects: subjects}); err != nil {
+			t.Fatal(err)
+		}
+		if _, err := b.js.CreateOrUpdateConsumer(b.ctx, stream, jetstream.ConsumerConfig{Durable: node + "_" + delivery.BuilderModule,
+			AckPolicy: jetstream.AckExplicitPolicy}); err != nil {
+			t.Fatal(err)
+		}
+	}
+	// The Go seat's remove, as its holder answers it; each call is kept.
+	rm, err := b.js.Conn().Subscribe("mesh.seat."+gopackageregistry.Seat+".call.remove.>", func(m *nats.Msg) {
+		var args map[string]any
+		_ = json.Unmarshal(m.Data, &args)
+		r.mu.Lock()
+		r.removes = append(r.removes, args)
+		r.mu.Unlock()
+		_ = m.Respond([]byte(`{"result":{},"node":"ctl"}`))
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { _ = rm.Unsubscribe() })
+	own := "mesh.mod." + delivery.BuilderModule + ".event.>"
+	if _, err := b.js.CreateStream(b.ctx, jetstream.StreamConfig{Name: "BUILDER_EVENTS", Subjects: []string{own}}); err != nil {
+		t.Fatal(err)
+	}
+	nc := b.js.Conn()
+	// As a build module hears it: on the contract's subject, read by the contract's decoder (BG2's late publish).
+	sub, err := nc.Subscribe(delivery.VersionNumberedSubject, func(m *nats.Msg) {
+		if nb, err := delivery.DecodeVersionNumbered(m.Data); err == nil {
+			r.mu.Lock()
+			r.numbered = append(r.numbered, nb)
+			r.mu.Unlock()
+		}
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { _ = sub.Unsubscribe() })
+	var listed []map[string]string
+	for _, v := range seatVersions {
+		listed = append(listed, map[string]string{"version": v})
+	}
+	for subject, answer := range map[string]any{
+		"mesh.seat." + ociartifactregistry.Seat + ".call.versions.>":          map[string]any{"versions": listed},
+		"mesh.mod.mesh-delivery-forge-bridge.call.bridge_tags.>":              map[string]any{"tags": []string{}},
+		"mesh.mod." + delivery.IndexerModule + ".call.indexer_requirements.>": map[string]any{"requirements": []string{}},
+	} {
+		reply, _ := json.Marshal(map[string]any{"result": answer, "node": "ctl"})
+		s, err := nc.Subscribe(subject, func(m *nats.Msg) { _ = m.Respond(reply) })
+		if err != nil {
+			t.Fatal(err)
+		}
+		t.Cleanup(func() { _ = s.Unsubscribe() })
+	}
+	return r
+}
+
+// of is every entry versions holds of name.
+func (r *registry) of(t *testing.T, name string) []versions.Entry {
+	t.Helper()
+	l, err := r.versions.ListKeysFiltered(r.b.ctx, versions.NameFilter(name))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer func() { _ = l.Stop() }()
+	var out []versions.Entry
+	for k := range l.Keys() {
+		e, err := r.versions.Get(r.b.ctx, k)
+		if err != nil {
+			t.Fatal(err)
+		}
+		var v versions.Entry
+		if err := json.Unmarshal(e.Value(), &v); err != nil {
+			t.Fatal(err)
+		}
+		out = append(out, v)
+	}
+	return out
+}
+
+// awaitOf reads name's entries until pred holds of them, within 20 s.
+func (r *registry) awaitOf(t *testing.T, name string, pred func([]versions.Entry) bool) []versions.Entry {
+	t.Helper()
+	var es []versions.Entry
+	for deadline := time.Now().Add(20 * time.Second); time.Now().Before(deadline); time.Sleep(50 * time.Millisecond) {
+		if es = r.of(t, name); pred(es) {
+			return es
+		}
+	}
+	t.Fatalf("versions of %s = %+v within 20 s", name, es)
+	return es
+}
+
+// published says the artifact seat's published for name@version, as its holder does.
+func (r *registry) published(t *testing.T, name, version, digest string) {
+	t.Helper()
+	r.outcome(t, ociartifactregistry.SubjectPublished, versions.Outcome{Name: name, Version: version, Digest: digest, Kind: "bundle", Holder: "distribution"})
+}
+
+// outcome says a seat's outcome on subject, as its holder does.
+func (r *registry) outcome(t *testing.T, subject string, o versions.Outcome) {
+	t.Helper()
+	data, _ := json.Marshal(o)
+	msg := nats.NewMsg(subject)
+	msg.Header.Set("x-event-id", subject+"-"+o.Name+"-"+o.Version)
+	msg.Data = data
+	if _, err := r.b.js.PublishMsg(r.b.ctx, msg); err != nil {
+		t.Fatal(err)
+	}
+}
+
+// answered writes a reasks value and reads it until the builder answered it, within 20 s.
+func (r *registry) answered(t *testing.T, key string, value []byte) build.ReAsk {
+	t.Helper()
+	if _, err := r.reasks.Put(r.b.ctx, key, value); err != nil {
+		t.Fatal(err)
+	}
+	var a build.ReAsk
+	for deadline := time.Now().Add(20 * time.Second); time.Now().Before(deadline); time.Sleep(50 * time.Millisecond) {
+		if e, err := r.reasks.Get(r.b.ctx, key); err == nil && json.Unmarshal(e.Value(), &a) == nil && !a.Answered.IsZero() {
+			return a
+		}
+	}
+	t.Fatalf("reasks.%s = %+v, not answered within 20 s", key, a)
+	return a
+}
+
+// awaitFinding reads the builder's finding key until it is there (raised) or gone, within 20 s.
+func (r *registry) awaitFinding(t *testing.T, key string, raised bool) {
+	t.Helper()
+	for deadline := time.Now().Add(20 * time.Second); time.Now().Before(deadline); time.Sleep(50 * time.Millisecond) {
+		if _, err := r.findings.Get(r.b.ctx, key); (err == nil) == raised {
+			return
+		}
+	}
+	t.Fatalf("the finding %s raised = %v within 20 s, want %v", key, !raised, raised)
+}
+
+// numberedOf are the version.numbered the builder said for name, in order.
+func (r *registry) numberedOf(name string) []string {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	var out []string
+	for _, nb := range r.numbered {
+		if nb.Name == name {
+			out = append(out, nb.Version)
+		}
+	}
+	return out
+}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/main.go

@@ -5,6 +5,7 @@
 package main
 
 import (
+	"cmp"
 	"context"
 	"fmt"
 	"io"
@@ -18,15 +19,18 @@ import (
 	"syscall"
 	"time"
 
-	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
+	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun"
+	"git.novox.be/novox/mesh-delivery/sdk/forms"
 
 	"github.com/nats-io/nats.go"
 	"github.com/nats-io/nats.go/jetstream"
 
 	"git.novox.be/novox/mesh-sdk/go/delivery"
 	"git.novox.be/novox/mesh-sdk/go/process"
+	"git.novox.be/novox/mesh-sdk/go/views"
 
 	"mesh-delivery-builder/internal/build"
+	"mesh-delivery-builder/internal/versions"
 )
 
 const (
@@ -61,22 +65,53 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 	if err != nil {
 		return err
 	}
-	modules, err := process.EssentialBucket(ctx, js, "builder", delivery.ModulesBucket, "know any fingerprint to build")
+	// The indexer's modules, manifests, candidates and packages and the assigner's placement are their owners' states, read by the
+	// first view of their read tools and then their views families, never their buckets (ADR 0615 §1, DLV-M1). An owner that
+	// is down never holds the start: each is read on a goroutine once its first view is answered, and until then the
+	// unanswered first view is the builder's finding.
+	calls, err := process.Connect(cred, nats.Name(cred.Node+"."+cred.Module+".calls"), nats.RetryOnFailedConnect(true))
 	if err != nil {
 		return err
 	}
-	manifests, err := process.EssentialBucket(ctx, js, "builder", delivery.ManifestsBucket, "read what a module builds")
+	defer calls.Close()
+	reader := &views.ProcessReader{Module: delivery.BuilderModule, Call: calls.Call, Logf: logger.Printf}
+	findingsKV := process.AwaitBucket(ctx, js, conn, findingsBucket, "the builder's findings, a first view unanswered past its bound among them, are said in its log only", logger.Printf)
+	reader.Findings = findingsKV.KV
+	modules, err := reader.Follow(delivery.IndexerModule, modulesState, delivery.IndexerModule+".indexer_read_modules", indexerViews)
+	if err != nil {
+		return err
+	}
+	manifests, err := reader.Follow(delivery.IndexerModule, manifestsState, delivery.IndexerModule+".indexer_read_manifests", indexerViews)
+	if err != nil {
+		return err
+	}
+	// The candidates' fingerprints are built too (issue 1684).
+	candidates, err := reader.Follow(delivery.IndexerModule, candidatesState, delivery.IndexerModule+".indexer_read_candidates", indexerViews)
+	if err != nil {
+		return err
+	}
+	// The indexer's packages, whose names a package is numbered under (design 32).
+	packages, err := reader.Follow(delivery.IndexerModule, delivery.PackagesState, delivery.IndexerModule+".indexer_read_packages", indexerViews)
+	if err != nil {
+		return err
+	}
+	placement, err := reader.Follow(delivery.AssignerModule, delivery.PlacementState, delivery.AssignerModule+".assigner_read_placement", assignerViews)
 	if err != nil {
 		return err
 	}
-	// The candidates' fingerprints are built too (issue 1684): a builder that cannot read them builds the trunk's.
-	candidates := process.OptionalBucket(ctx, js, delivery.CandidatesBucket, "no candidate's fingerprint is built until the builder starts again; the trunk's are", logger.Printf)
 	bound := defaultStepBound
 	if v := strings.TrimSpace(getenv("MESH_BUILDER_STEP_BOUND")); v != "" {
 		if bound, err = time.ParseDuration(v); err != nil {
 			return fmt.Errorf("MESH_BUILDER_STEP_BOUND: %w", err)
 		}
 	}
+	// An unanswered tag ask is narrated every TagAskBound (design 51: five minutes); a test gives a shorter one.
+	tagAskBound := versions.TagAskBound
+	if v := strings.TrimSpace(getenv("MESH_BUILDER_TAG_ASK_BOUND")); v != "" {
+		if tagAskBound, err = time.ParseDuration(v); err != nil {
+			return fmt.Errorf("MESH_BUILDER_TAG_ASK_BOUND: %w", err)
+		}
+	}
 	tools := &buildrun.ToolchainSet{}
 	// Each build module's part of a build is an ask on its build seat's stream, pulled by a build node with a free slot
 	// (novox/hq ADR 0525): the builder chooses no node, so it reads neither presence nor have and holds no capacity.
@@ -103,12 +138,31 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 	heard := buildrun.HearEnds(ctx, asks, asks, buildModules, logger.Printf)
 	conn.SetReconnectHandler(func(*nats.Conn) { hearing.Again(); heard.Nudge("") })
 	// The builder asks the controller, as its own account, whether the artifact store still holds a done key's blobs
-	// (the seat verb held, novox/hq issue 1937) before it leaves the key done.
-	calls, err := process.Connect(cred, nats.Name(cred.Node+"."+cred.Module+".calls"), nats.RetryOnFailedConnect(true))
-	if err != nil {
-		return err
-	}
-	defer calls.Close()
+	// (the seat verb held, novox/hq issue 1937) before it leaves the key done, on its calls connection.
+	// The builder numbers each trunk build at its claim (novox/hq design 51 *The versions*): its state versions, bound once
+	// the bus holds it; the floor's three sources asked as its own account; each new number said as version.numbered.
+	versionsKV := process.AwaitBucket(ctx, js, conn, versions.Bucket, "no trunk build is numbered: each is built unnumbered and published by its digest", logger.Printf)
+	found := &findings{kv: findingsKV, logf: logger.Printf, now: time.Now}
+	floorWaits := &versions.FloorWaits{Logf: logger.Printf, Said: found.floorSaid(context.WithoutCancel(ctx))}
+	// The names waiting on their floor are kept in the state floor-waits (DLV-B4): a restarted builder takes them in, so
+	// their silent sources' events still wake them; until the state is bound they are kept here only.
+	process.AwaitBucket(ctx, js, conn, versions.FloorWaitsBucket, "the names waiting on their floor are kept in memory only, and builder_floor_waits shows none", logger.Printf).
+		Ready(func(kv jetstream.KeyValue) {
+			floorWaits.Keep(kvKeeper{ctx: ctx, kv: kv}, heldFloorWaits(ctx, kv, logger.Printf))
+		})
+	// A package is numbered under its name in its ecosystem, read from the indexer's packages state (design 32).
+	numberer := &versions.Numberer{Versions: versions.Versions{Store: awaitedVersions{versionsKV}}, Floor: floorVia(calls.Call), Waits: floorWaits,
+		Names: versions.NamesIn(indexerPackages{packages}),
+		Said: func(nb delivery.VersionNumbered) {
+			if err := emitNumbered(context.WithoutCancel(ctx), js, cred, nb); err != nil {
+				logger.Printf("%v", err)
+			}
+		}}
+	// A publish that ends badly is a finding (design 51 *Health and conditions*): a holder's refused, a version no holder
+	// answered within its bound (a key of the state bounds with its own time to live), a seat's outcome that does not read.
+	pubBoundsKV := process.AwaitBucket(ctx, js, conn, versions.BoundsBucket, "a publish no holder answers, and a node holding the old form seven days, are not raised", logger.Printf)
+	pubs := &publishes{bounds: pubBoundsKV.KV, versions: numberer.Versions, findings: found, bound: versions.PublishBound, logf: logger.Printf}
+	numberer.Publishing = pubs.arm
 	b := &build.Builder{
 		Claimer: build.Claimer{Store: kvStore{builds}, By: cred.Node + "." + cred.Module},
 		Asks:    buildrun.Asker{Publisher: asks, Waiter: buildrun.LostAskWaiter{Inner: heard, Dead: dead, Hearing: hearing}, Bound: bound},
@@ -120,15 +174,55 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 		Manifests:  manifestReader{manifests},
 		Logf:       logger.Printf,
 		Stored:     storedVia(calls.Call),
+		Node:       cred.Node,
 	}
+	tagAsksKV := process.AwaitBucket(ctx, js, conn, versions.TagAsksBucket, "builder_tag and builder_untag are not answered", logger.Printf)
+	// A check's build of a head a kept tag ask names numbers its packages tagged (design 51 *Tagged versions*), and the ask
+	// is marked numbered with its versions.
+	b.Tags = tagsVia(tagAsksKV.KV, logger.Printf)
+	b.Numbers = build.VersionNumbers{N: numberer, TagNumbered: tagNumbered(tagAsksKV.KV, logger.Printf, time.Now)}
+	// An ask not answered within five minutes is narrated with what it waits on: its bound's end on the bus says when.
+	boundsKV := process.AwaitBucket(ctx, js, conn, versions.TagAskBoundsBucket, "an unanswered tag ask is not narrated", logger.Printf)
+	bounds := &tagBounds{asks: tagAsksKV.KV, bounds: boundsKV.KV, bound: tagAskBound, waits: floorWaits.Waiting, logf: logger.Printf, now: time.Now,
+		log: func(e delivery.BuildLogEntry) { b.Log(e) }}
+	// A state bound later numbers the builds looked at without it.
+	versionsKV.Ready(func(jetstream.KeyValue) { b.Reconsider(ctx) })
+	// The versions' hand acts (builder_publish_again, builder_floor_again) come through reasks, as builder_build_again.
+	acts := versions.Acts{Numberer: numberer, Done: doneVia(b), Reconsider: b.Reconsider, Remove: removeVia(calls.Call),
+		BuildAgain: func(ctx context.Context, module, fp, why, by string) (string, bool) {
+			r := b.BuildAgain(ctx, module, fp, why, by, buildAgainBound)
+			if r.Refused != "" {
+				return r.Refused, true
+			}
+			if r.Failed != "" {
+				return "built again, and it failed before its asks were put: " + r.Failed, false
+			}
+			return fmt.Sprintf("built again as revision %d", r.Revision), false
+		}}
 	// A candidate's preview is merged onto the trunk head the indexer previewed it onto: source.main at the candidate's base
 	// revision (the gate's source state). The source's revisions are watched with their history (a direct get of one revision
 	// is not what a read grants): a revision heard after the candidate that names it builds that candidate then. Where it
 	// cannot be read the trunk's keys are built and the candidates wait (issue 1945).
-	errs := make(chan error, 6)
-	trunks := &trunkSource{ctx: ctx, js: js, heads: &sourceHeads{}, moved: b.TrunkMoved, errs: errs, logf: logger.Printf}
+	errs := make(chan error, 10)
+	trunks := &trunkSource{ctx: ctx, js: js, heads: &sourceHeads{}, moved: func(ctx context.Context) {
+		// A source revision heard is the forge's merge: it wakes a floor whose bridge_tags was silent (design 51 *The floor*).
+		(&floorWake{b: b, waits: floorWaits, logf: logger.Printf}).wake(ctx, versions.WakeForge, "", "")
+		b.TrunkMoved(ctx)
+	}, errs: errs, logf: logger.Printf}
 	trunks.start()
 	b.Trunk = trunks.head
+	// The builder's log (ADR 0571 §1): each build's start and end in its module log `build-log`, read by the view, the
+	// indexer and the assigner through their reads, and by the operator's command nox builds through the tool builder_builds_since.
+	b.Log = func(e delivery.BuildLogEntry) {
+		if e.Node == "" { // a narration of no one build (a tag ask, the old form's window) is this instance's
+			e.Node = cred.Node
+		}
+		if err := appendLog(context.WithoutCancel(ctx), js, cred, e); err != nil {
+			logger.Printf("%v", err)
+		}
+		// A failed trunk build is the builder's finding build-failed, cleared by a later done one (DLV-B7).
+		found.buildEnded(context.WithoutCancel(ctx), e)
+	}
 	b.Said = func(e build.AskedAgain) {
 		if err := emitAskedAgain(context.WithoutCancel(ctx), js, cred, e); err != nil {
 			logger.Printf("%v", err)
@@ -153,46 +247,223 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 	}
 	// The toolchains first, so a build that starts from the first modules value finds the nodes.
 	watch := newToolchainWatch(ctx, js, tools, b.NodesChanged, logger)
-	// Only the toolchain reports of nodes the build module is assigned to count (issue 1940): the controller's
-	// assignments are settled first, so the toolchains settle through the gate already knowing them.
-	gate := newToolchainGate([]string{buildrun.GoBuildModule, buildrun.NodeBuildModule}, tools.Put, logger.Printf)
+	// Only the toolchain reports of nodes the catalogue places the build module on count (issue 1940, ADR 0549 §3): the
+	// placement is settled first, so the toolchains settle through the gate already knowing it.
+	gate := buildrun.NewToolchainGate([]string{buildrun.GoBuildModule, buildrun.NodeBuildModule}, tools.Put, logger.Printf)
 	watch.put = gate.Toolchain
-	assignErrs, err := watchAssignments(ctx, js, gate, b.NodesChanged, logger)
-	if err != nil {
-		return err
+	// What each counted node's engine reads (ADR 0618 §2, ADR 0624 §1): asked through the node-engine seat's verb as the
+	// builder's own account, for every node the placement names, and kept in the state engine-reads once it is bound.
+	reads := newEngineReads(calls.CallOn, gate, logger.Printf)
+	// The old reference form's window over them (DLV-B9), kept in the state old-form once it is bound; builder_old_form
+	// reads it and drops a retired node by hand.
+	reads.ctx = context.WithoutCancel(ctx)
+	reads.window = &oldForm{forms: forms.Current, findings: found, logf: logger.Printf, now: time.Now, log: func(e delivery.BuildLogEntry) { b.Log(e) },
+		bounds: pubBoundsKV.KV,
+		said: func(body versions.OldFormClosedBody) {
+			if err := emitEvent(context.WithoutCancel(ctx), js, cred, versions.OldFormClosedEvent, "old-form-closed-"+body.At.Format(time.RFC3339Nano), body); err != nil {
+				logger.Printf("saying %s: %v", versions.OldFormClosedEvent, err)
+			}
+		}}
+	acts.DropOldForm = func(ctx context.Context, node, by, why string, at time.Time) (string, error) {
+		answer, err := reads.window.drop(ctx, node, by, why, at)
+		if err == nil {
+			reads.stepWindow()
+		}
+		return answer, err
 	}
+	process.AwaitBucket(ctx, js, conn, versions.OldFormBucket, "the old form's window is kept in memory only, and builder_old_form shows none", logger.Printf).
+		Ready(func(kv jetstream.KeyValue) {
+			reads.window.bind(context.WithoutCancel(ctx), kv)
+			reads.stepWindow()
+		})
+	gate.OnPlaced = reads.placed
+	b.Forms = reads.built
+	// Until the placement's first view is answered the gate passes every report on, as before the placement is settled.
+	placementErrs := make(chan error, 1)
+	go func() {
+		select {
+		case <-ctx.Done():
+			return
+		case <-placement.Follower().Ready():
+		}
+		pe, err := buildrun.FollowPlacement(ctx, reader, gate, b.NodesChanged, logger.Printf)
+		if err != nil {
+			placementErrs <- err
+			return
+		}
+		placementErrs <- <-pe
+	}()
 	if err := watch.start(); err != nil {
 		return err
 	}
 	// A build module says each time it wrote its toolchains key: its stream, and the builder's durable consumer on it, are
 	// made by the controller. Where the stream is not there yet the builder says so and is started again with the build
 	// module.
-	for _, module := range []string{buildrun.GoBuildModule, buildrun.NodeBuildModule} {
-		stream := toolchainStreams[module]
-		cons, err := cred.EventConsumer(ctx, js, stream)
-		if err != nil {
-			logger.Printf("the consumer %s_%s on %s does not exist yet, so %s's reports are not heard until the builder starts again: %v", cred.Node, cred.Module, stream, module, err)
-			continue
-		}
-		cc, err := process.HearEvents(cons, func(m jetstream.Msg) { watch.Reported(m) }, logger.Printf)
-		if err != nil {
-			return err
-		}
-		defer cc.Stop()
+	// Each consumer that is not there yet is the finding family-not-heard naming its stream until it binds at a later
+	// start (heard.Writer; ADR 0615 §5); one there that cannot be heard stops the builder, as before.
+	notHeard := found.notHeard(ctx)
+	var stopped error
+	hear := func(stream, consequence string, each func(jetstream.Msg)) {
+		_ = notHeard.Bind(stream, consequence, func() error {
+			cons, err := cred.EventConsumer(ctx, js, stream)
+			if err != nil {
+				return fmt.Errorf("the consumer %s_%s on %s does not exist yet: %w", cred.Node, cred.Module, stream, err)
+			}
+			cc, err := process.HearEvents(cons, each, logger.Printf)
+			if err != nil {
+				stopped = cmp.Or(stopped, err)
+				return err
+			}
+			go func() { <-ctx.Done(); cc.Stop() }()
+			return nil
+		})
 	}
-	// The controller says artifacts-gone when its take-in found a key's blob gone (issue 1937): the builder's durable
-	// consumer on EVENTS, made by the controller from the manifest's consumes. Where it is not there yet the builder says
+	for _, module := range []string{buildrun.GoBuildModule, buildrun.NodeBuildModule} {
+		hear(toolchainStreams[module], module+"'s toolchain reports are not heard until the builder starts again", func(m jetstream.Msg) { watch.Reported(m) })
+	}
+	// The seat mesh-artifact-sweep says artifacts-gone when it found a key's blob gone (issue 1937, ADR 0571 §2): the
+	// builder's durable consumer on EVENTS, made by the grants part from the manifest's consumes. Where it is not there yet the builder says
 	// so; it still asks held at its start and at every module value.
-	switch cons, err := cred.EventConsumer(ctx, js, eventsStream); {
-	case err != nil:
-		logger.Printf("the consumer %s_%s on %s does not exist yet, so %s is not heard until the builder starts again: %v",
-			cred.Node, cred.Module, eventsStream, delivery.ArtifactsGoneEvent, err)
-	default:
-		cc, err := process.HearEvents(cons, func(m jetstream.Msg) { heardGone(ctx, b, m, logger.Printf) }, logger.Printf)
-		if err != nil {
-			return err
+	// The same consumer carries what wakes a floor (design 51 *The floor*): the indexer's manifest-accepted and the
+	// condition keeper's condition-cleared.
+	floor := floorWake{b: b, waits: floorWaits, logf: logger.Printf}
+	// And the four registry seats' published, refused and removed (DLV-B4), which move a numbered version.
+	seats := seatHearer{n: numberer, b: b, logf: logger.Printf, pub: pubs}
+	hear(eventsStream, delivery.ArtifactsGoneEvent+", what wakes a floor, the registry seats' words and manifest-reads-changed are not heard until the builder starts again", func(m jetstream.Msg) {
+		if reads.heard(m, logger.Printf) || floor.heard(ctx, m) || seats.heard(ctx, m) { // reads: the node-engine seat's manifest-reads-changed (ADR 0618 §4)
+			return
+		}
+		heardGone(ctx, b, m, logger.Printf)
+	})
+	if stopped != nil {
+		return stopped
+	}
+	reader.Start(ctx, js, cred, process.AwaitBucket(ctx, js, conn, firstViewsBucket, "builder_first_views reads nothing and builder_first_view_again is not heard", logger.Printf))
+	// The modules, once their first views and the manifests' are answered: what a module builds is read from the manifests.
+	go func() { errs <- buildFromModules(ctx, b, modules, manifests, candidates) }()
+	// A package's name heard in the indexer's packages looks at its module again, so a done build is numbered then.
+	go func() { errs <- followPackages(ctx, packages, b, logger.Printf) }()
+	// A person asks a key's build again with builder_ask_again, which writes the reasks state (issue 1945): watched, as
+	// every other input. The builder asks again by itself without it.
+	// A state not on the bus yet at this start is watched once it appears (issue 1790).
+	process.AwaitBucket(ctx, js, conn, build.ReAsksBucket, "builder_ask_again is not heard; an ask that can no longer be answered is still asked again by itself", logger.Printf).Ready(func(kv jetstream.KeyValue) {
+		eachReAsk := func(e jetstream.KeyValueEntry) { reAsked(ctx, b, acts, kv, e, logger.Printf) }
+		if rw, err := settle(ctx, kv, eachReAsk); err != nil {
+			process.NotWatched(logger.Printf, build.ReAsksBucket, err, "builder_ask_again is not heard until the builder starts again")
+		} else {
+			go func() { errs <- follow(ctx, rw, eachReAsk) }()
+		}
+	})
+	// A tag ask or a branch's removal by hand (builder_tag, builder_untag) is written to tag-asks and answered there
+	// (design 51 *Tagged versions*); the checker's tag-wanted and the branch's end join it on their consumers (DLV-B6).
+	tagAsksKV.Ready(func(kv jetstream.KeyValue) {
+		each := func(e jetstream.KeyValueEntry) {
+			tagAsked(ctx, acts, kv, e, logger.Printf)
+			if !opOf(e) {
+				bounds.disarm(ctx, e.Key())
+			} else if t, err := versions.DecodeTagAsk(e.Value()); err == nil {
+				bounds.asked(ctx, e.Key(), t)
+			}
+		}
+		if tw, err := settle(ctx, kv, each); err != nil {
+			process.NotWatched(logger.Printf, versions.TagAsksBucket, err, "builder_tag and builder_untag are not answered until the builder starts again")
+		} else {
+			go func() { errs <- follow(ctx, tw, each) }()
+		}
+	})
+	pubBoundsKV.Ready(func(kv jetstream.KeyValue) {
+		each := func(e jetstream.KeyValueEntry) {
+			if versions.IsOldFormBound(e.Key()) {
+				if e.Operation() == jetstream.KeyValuePurge {
+					reads.stepWindow() // a node's seven days ended: the step raises old-form-held now
+				}
+				return
+			}
+			pubs.ended(ctx, e)
+		}
+		watchBounds(ctx, kv, each, found.notHeard(ctx), errs, logger.Printf)
+	})
+	boundsKV.Ready(func(kv jetstream.KeyValue) {
+		each := func(e jetstream.KeyValueEntry) { bounds.ended(ctx, e) }
+		if bw, err := settle(ctx, kv, each); err != nil {
+			process.NotWatched(logger.Printf, versions.TagAskBoundsBucket, err, "an unanswered tag ask is not narrated until the builder starts again")
+		} else {
+			go func() { errs <- follow(ctx, bw, each) }()
+		}
+	})
+	// A person reads a build seat's stream with builder_seat_queue, which writes the queues state (issue 1945 note 62): the
+	// builder alone may read the stream, so it answers there.
+	process.AwaitBucket(ctx, js, conn, build.QueuesBucket, "builder_seat_queue is not answered", logger.Printf).Ready(func(kv jetstream.KeyValue) {
+		eachRead := func(e jetstream.KeyValueEntry) { queueRead(ctx, heldOnTheBus{js}, kv, e, logger.Printf) }
+		if qw, err := settle(ctx, kv, eachRead); err != nil {
+			process.NotWatched(logger.Printf, build.QueuesBucket, err, "builder_seat_queue is not answered until the builder starts again")
+		} else {
+			go func() { errs <- follow(ctx, qw, eachRead) }()
+		}
+	})
+	// A branch's end removes its tagged versions (design 51 *Tagged versions*, DLV-B6): the forge bridge's merged, a pull's
+	// closed or branch-deleted on the builder's durable consumer of its stream; each forge message also wakes a floor whose
+	// bridge_tags was silent. The checker's tag-wanted is kept in tag-asks. A consumer not there yet is said.
+	ends := &branchEnds{acts: acts, findings: found, tagAsks: tagAsksKV.KV, logf: logger.Printf, now: time.Now,
+		wake: func(ctx context.Context) {
+			(&floorWake{b: b, waits: floorWaits, logf: logger.Printf}).wake(ctx, versions.WakeForge, "", "")
+		}}
+	for _, c := range []struct {
+		stream, what string
+		hear         func(jetstream.Msg)
+	}{
+		{forgeStream, "a branch's end", func(m jetstream.Msg) { ends.heard(ctx, m) }},
+		{checkerAsksStream, "the checker's tag-wanted", func(m jetstream.Msg) {
+			tagWanted(ctx, tagAsksKV.KV(), m, delivery.CheckerModule, time.Now(), logger.Printf)
+		}},
+	} {
+		hear(c.stream, c.what+" is not heard until the builder starts again", c.hear)
+	}
+	if stopped != nil {
+		return stopped
+	}
+	// The state engine-reads, new with ADR 0618 (issue 1790's kind): until it is on the bus each statement is kept in memory
+	// only, and builder_engine_reads answers nothing.
+	process.AwaitBucket(ctx, js, conn, engineReadsBucket, "what each node's engine reads is kept in memory only", logger.Printf).Ready(func(kv jetstream.KeyValue) {
+		reads.bind(ctx, kv, errs, logger.Printf)
+	})
+	logger.Printf("started on %s", cred.Node)
+	select {
+	case <-ctx.Done():
+		b.Wait()
+		return nil
+	case err := <-errs:
+		return err
+	case err := <-placementErrs:
+		return err
+	case err := <-watch.errs:
+		return err
+	}
+}
+
+// The builder's own state of its first views (views.StatusState); its findings (findingsBucket) are where the condition
+// keeper raises a first view unanswered past its bound (ADR 0615 §6).
+var firstViewsBucket = delivery.BuilderModule + "_" + views.StatusState
+
+// The indexer's states the builder follows (delivery.ModulesBucket, ManifestsBucket, CandidatesBucket), and the owners'
+// views families as their manifests' `streams` name them.
+const (
+	indexerViews    = "indexer-views"
+	assignerViews   = "assigner-views"
+	modulesState    = "modules"
+	manifestsState  = "manifests"
+	candidatesState = "candidates"
+)
+
+// buildFromModules builds from the indexer's modules and candidates once the first views of the modules, the manifests and
+// the candidates are answered (never at the start: an indexer that is down holds no other part of it), and follows them.
+func buildFromModules(ctx context.Context, b *build.Builder, modules, manifests, candidates *views.Picture) error {
+	for _, p := range []*views.Picture{modules, manifests, candidates} {
+		select {
+		case <-ctx.Done():
+			return nil
+		case <-p.Follower().Ready():
 		}
-		defer cc.Stop()
 	}
 	each := func(e jetstream.KeyValueEntry) {
 		if opOf(e) {
@@ -217,48 +488,12 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 			b.ForgetCandidate(e.Key())
 		}
 	}
-	if candidates != nil {
-		cw, err := settle(ctx, candidates, eachCandidate)
-		if err != nil {
-			process.NotWatched(logger.Printf, delivery.CandidatesBucket, err, "no candidate's fingerprint is built until the builder starts again")
-		} else {
-			go func() { errs <- follow(ctx, cw, eachCandidate) }()
-		}
-	}
-	// A person asks a key's build again with builder_ask_again, which writes the reasks state (issue 1945): watched, as
-	// every other input. The builder asks again by itself without it.
-	// A state not on the bus yet at this start is watched once it appears (issue 1790).
-	process.AwaitBucket(ctx, js, conn, build.ReAsksBucket, "builder_ask_again is not heard; an ask that can no longer be answered is still asked again by itself", logger.Printf).Ready(func(kv jetstream.KeyValue) {
-		eachReAsk := func(e jetstream.KeyValueEntry) { reAsked(ctx, b, kv, e, logger.Printf) }
-		if rw, err := settle(ctx, kv, eachReAsk); err != nil {
-			process.NotWatched(logger.Printf, build.ReAsksBucket, err, "builder_ask_again is not heard until the builder starts again")
-		} else {
-			go func() { errs <- follow(ctx, rw, eachReAsk) }()
-		}
-	})
-	// A person reads a build seat's stream with builder_seat_queue, which writes the queues state (issue 1945 note 62): the
-	// builder alone may read the stream, so it answers there.
-	process.AwaitBucket(ctx, js, conn, build.QueuesBucket, "builder_seat_queue is not answered", logger.Printf).Ready(func(kv jetstream.KeyValue) {
-		eachRead := func(e jetstream.KeyValueEntry) { queueRead(ctx, heldOnTheBus{js}, kv, e, logger.Printf) }
-		if qw, err := settle(ctx, kv, eachRead); err != nil {
-			process.NotWatched(logger.Printf, build.QueuesBucket, err, "builder_seat_queue is not answered until the builder starts again")
-		} else {
-			go func() { errs <- follow(ctx, qw, eachRead) }()
-		}
-	})
-	logger.Printf("started on %s", cred.Node)
-	go func() { errs <- follow(ctx, w, each) }()
-	select {
-	case <-ctx.Done():
-		b.Wait()
-		return nil
-	case err := <-errs:
-		return err
-	case err := <-assignErrs:
-		return err
-	case err := <-watch.errs:
+	cw, err := settle(ctx, candidates, eachCandidate)
+	if err != nil {
 		return err
 	}
+	go func() { _ = follow(ctx, cw, eachCandidate) }()
+	return follow(ctx, w, each)
 }
 
 // sourceHeads are the trunk heads of each revision of the gate's source.main the watch delivered, the newest

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/oldform.go

@@ -0,0 +1,187 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"slices"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/health"
+
+	"git.novox.be/novox/mesh-delivery/sdk/forms"
+
+	"mesh-delivery-builder/internal/versions"
+)
+
+// oldForm keeps the old reference form's window (design 51 *Every build keeps the old reference form*, DLV-B9) in the
+// state old-form: stepped on every change of what the counted nodes state, of the placement, on a hand drop and at each
+// build key written, never on a timer. A node holding it seven days is the finding old-form-held; its close is said once
+// as version.old-form-closed and in the builder's log.
+type oldForm struct {
+	forms    forms.ArtifactForms
+	findings *findings
+	// said emits version.old-form-closed.
+	said func(versions.OldFormClosedBody)
+	// log writes the close into the builder's build log (build.said); nil writes none.
+	log  func(delivery.BuildLogEntry)
+	logf func(string, ...any)
+	now  func() time.Time
+
+	// bounds is the builder's state bounds: each node holding the window has a key there whose time to live ends at its
+	// seven days, so old-form-held is raised then, not at the next change (review round 1); nil keeps none.
+	bounds func() jetstream.KeyValue
+
+	mu sync.Mutex
+	w  versions.OldFormWindow
+	kv jetstream.KeyValue
+	// overdue are the nodes the finding is raised for now.
+	overdue []string
+}
+
+// bind takes the kept window in, so a restarted builder keeps each node's since and the nodes dropped by hand, and keeps
+// every later step in kv.
+func (o *oldForm) bind(ctx context.Context, kv jetstream.KeyValue) {
+	e, err := kv.Get(ctx, versions.OldFormKey)
+	o.mu.Lock()
+	defer o.mu.Unlock()
+	switch {
+	case errors.Is(err, jetstream.ErrKeyNotFound):
+	case err != nil:
+		o.logf("%s.%s cannot be read, so the window starts again: %v", versions.OldFormState, versions.OldFormKey, err)
+	default:
+		w, err := versions.DecodeOldFormWindow(e.Value())
+		if err != nil {
+			o.logf("%v; the window starts again", err)
+			break
+		}
+		// Taken in under what was stepped before the state was bound: the kept since and drops are the older truth.
+		for n, s := range o.w.Since {
+			if _, ok := w.Since[n]; !ok && w.Open && slices.Contains(w.Holding, n) {
+				w.Since[n] = s
+			}
+		}
+		for _, d := range o.w.Dropped {
+			w, _ = w.Drop(d.Node, d.By, d.Why, d.At)
+		}
+		o.w = w
+	}
+	o.kv = kv
+	o.keep(ctx)
+}
+
+// dropped is the nodes dropped by hand.
+func (o *oldForm) dropped() map[string]bool {
+	o.mu.Lock()
+	defer o.mu.Unlock()
+	return o.w.DroppedSet()
+}
+
+// step moves the window to what counted states.
+// named is every node the read named (the placement's nodes before any is dropped), counted the statements of those
+// still counted: a read naming no node judges nothing (delivery.StepWindow), so it never closes the window.
+func (o *oldForm) step(ctx context.Context, named []string, counted map[string][]string) {
+	o.mu.Lock()
+	defer o.mu.Unlock()
+	before := o.w
+	next, closed, overdue := o.w.Step(named, versions.Holding(o.forms, counted, o.w.DroppedSet()), o.now())
+	o.w = next
+	if !slices.Equal(before.Holding, next.Holding) || before.Open != next.Open || closed {
+		o.keep(ctx)
+	}
+	for _, n := range o.overdue {
+		if !slices.Contains(overdue, n) {
+			o.findings.clear(ctx, versions.OldFormHeld, health.ScopeMachine, n)
+		}
+	}
+	for _, n := range overdue {
+		o.findings.raise(ctx, finding{kind: versions.OldFormHeld, scope: health.ScopeMachine, id: n,
+			summary: fmt.Sprintf("the node-engine of %s has read only an older reference form since %s, so every build key still carries it",
+				n, next.Since[n].Format(time.RFC3339)),
+			headline:    "A node holds the old reference form",
+			explanation: "The builder writes an older reference form into every build key while a counted node's engine reads none of the newest (ADR 0624 §1); this node has held it seven days.",
+			resolved:    "The node's engine states the newest form, the node leaves the placement, or it is dropped as retired.",
+			needs:       "builder_old_form shows the window; a retired node is dropped there by hand; builder_engine_reads asks the node again."})
+	}
+	o.overdue = overdue
+	o.keepBounds(ctx, before, next, overdue)
+	if closed {
+		body := next.Closing()
+		line := fmt.Sprintf("the old reference form's window closed at %s: no counted node-engine reads only an older form (last held by %s; dropped by hand: %d); new build keys leave it out",
+			body.At.Format(time.RFC3339), strings.Join(body.LastHolding, ", "), len(body.Dropped))
+		o.logf("%s", line)
+		// In the build log too (design 51 *The node-engine's own build*), under the builder's own key, the window's key
+		// standing for the fingerprint: the close is no one build's.
+		if o.log != nil {
+			o.log(delivery.BuildLogEntry{Event: delivery.BuildSaidEvent, Module: delivery.BuilderModule, FP: versions.OldFormKey,
+				At: body.At.UTC(), Line: line, Why: versions.SaidOldFormClosed})
+		}
+		if o.said != nil {
+			o.said(body)
+		}
+	}
+}
+
+// keepBounds writes a bound for each node holding the window and not yet overdue, ending at its seven days, and deletes
+// the bound of each node that no longer holds it. A standing bound keeps its time (a Create). Called with mu held.
+func (o *oldForm) keepBounds(ctx context.Context, before, next versions.OldFormWindow, overdue []string) {
+	if o.bounds == nil {
+		return
+	}
+	kv := o.bounds()
+	if kv == nil {
+		return
+	}
+	for _, n := range before.Holding {
+		if !slices.Contains(next.Holding, n) {
+			if err := kv.Delete(ctx, versions.OldFormBoundKey(n)); err != nil && !errors.Is(err, jetstream.ErrKeyNotFound) {
+				o.logf("the old form's bound of %s is not deleted: %v", n, err)
+			}
+		}
+	}
+	for _, n := range next.Holding {
+		left := next.Since[n].Add(versions.FindingAfter).Sub(o.now())
+		if slices.Contains(overdue, n) || left <= 0 {
+			continue
+		}
+		if left < time.Second {
+			left = time.Second // the bus's least time to live
+		}
+		if _, err := kv.Create(ctx, versions.OldFormBoundKey(n), versions.EncodeBound("the seven days "+n+" holds the old form's window", o.now().Add(left)), jetstream.KeyTTL(left)); err != nil && !errors.Is(err, jetstream.ErrKeyExists) {
+			o.logf("the old form's bound of %s is not written, so its seven days are seen at the next change only: %v", n, err)
+		}
+	}
+}
+
+// drop is builder_old_form's drop: the node leaves the count, the window is stepped by the caller.
+func (o *oldForm) drop(ctx context.Context, node, by, why string, at time.Time) (string, error) {
+	o.mu.Lock()
+	defer o.mu.Unlock()
+	w, err := o.w.Drop(node, by, why, at)
+	if err != nil {
+		return "", err
+	}
+	o.w = w
+	o.keep(ctx)
+	return node + " dropped from the old form's count by hand; the window is stepped now", nil
+}
+
+// keep writes the window, once the state is bound; until then it is kept here only. Called with mu held.
+func (o *oldForm) keep(ctx context.Context) {
+	if o.kv == nil {
+		return
+	}
+	raw, err := json.Marshal(o.w)
+	if err == nil {
+		_, err = o.kv.Put(ctx, versions.OldFormKey, raw)
+	}
+	if err != nil {
+		o.logf("%s.%s cannot be written: %v", versions.OldFormState, versions.OldFormKey, err)
+	}
+}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/publishbounds.go

@@ -0,0 +1,129 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"time"
+
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-sdk/go/health"
+	"git.novox.be/novox/mesh-sdk/go/process"
+
+	"git.novox.be/novox/mesh-delivery/sdk/heard"
+
+	"mesh-delivery-builder/internal/versions"
+)
+
+// publishes raises and clears the builder's findings of a publish that ended badly (versions/publish.go): a holder's
+// refused, a version unanswered past its bound, kept as a key of the state bounds with its own time to live, and a seat's
+// outcome that does not read.
+type publishes struct {
+	bounds   func() jetstream.KeyValue
+	versions versions.Versions
+	findings *findings
+	bound    time.Duration
+	logf     func(string, ...any)
+}
+
+// arm writes the version's bound when none stands, so a standing bound keeps its time. A bound that cannot be written
+// would never end, so the version is publish-unanswered at once (review round 2): the finding says why.
+func (p *publishes) arm(ctx context.Context, e versions.Entry) {
+	kv := p.bounds()
+	var err error
+	if kv == nil {
+		err = fmt.Errorf("%s is not on the bus yet", versions.BoundsBucket)
+	} else if _, err = kv.Create(ctx, versions.PublishBoundKey(e.Name, e.Version), versions.EncodeBound("the publish of "+e.Name+"@"+e.Version+" to "+e.Seat, time.Now().Add(p.bound)), jetstream.KeyTTL(p.bound)); errors.Is(err, jetstream.ErrKeyExists) {
+		err = nil
+	}
+	if err == nil {
+		return
+	}
+	p.logf("the publish bound of %s@%s is not written, so it is raised unanswered now: %v", e.Name, e.Version, err)
+	p.unanswered(ctx, e, fmt.Sprintf("its bound could not be written (%v), so the builder cannot wait on the holder's word", err))
+}
+
+// unanswered raises publish-unanswered about e's name, saying why.
+func (p *publishes) unanswered(ctx context.Context, v versions.Entry, why string) {
+	p.findings.raise(ctx, finding{kind: versions.PublishUnanswered, scope: health.ScopeModule, id: v.Name,
+		summary:     fmt.Sprintf("%s said neither published nor refused of %s@%s: %s", v.Seat, v.Name, v.Version, why),
+		headline:    "A registry seat did not answer a publish",
+		explanation: "The builder built and numbered " + v.Name + " " + v.Version + " and asked " + v.Seat + " to publish it; no word of its holder is known, so the build says done while the version may not be in the registry.",
+		resolved:    "That version is published, or a later version of " + v.Name + " is.",
+		needs:       "a look at the holder of " + v.Seat + " (its health and log); builder_publish_again asks the publish again."})
+}
+
+// heard is told each holder's word the numberer took in: published clears the name's findings, refused raises
+// publish-refused with the holder's reason, and either ends the version's bound.
+func (p *publishes) heard(ctx context.Context, seat, event string, o versions.Outcome) {
+	if o.Version != "" {
+		if kv := p.bounds(); kv != nil {
+			if err := kv.Delete(ctx, versions.PublishBoundKey(o.Name, o.Version)); err != nil && !errors.Is(err, jetstream.ErrKeyNotFound) {
+				p.logf("the publish bound of %s@%s is not ended: %v", o.Name, o.Version, err)
+			}
+		}
+	}
+	switch event {
+	case versions.HeardPublished:
+		p.findings.clear(ctx, versions.PublishRefused, health.ScopeModule, o.Name)
+		p.findings.clear(ctx, versions.PublishUnanswered, health.ScopeModule, o.Name)
+	case versions.HeardRefused:
+		reason := o.Reason
+		if reason == "" {
+			reason = "it gave no reason"
+		}
+		p.findings.raise(ctx, finding{kind: versions.PublishRefused, scope: health.ScopeModule, id: o.Name,
+			summary:     fmt.Sprintf("%s refused to publish %s@%s (digest %s): %s", seat, o.Name, o.Version, o.Digest, reason),
+			headline:    "A registry seat refused a publish",
+			explanation: "The builder built and numbered " + o.Name + " " + o.Version + ", and the holder of " + seat + " refused to store it, so that version is not in the registry.",
+			resolved:    "That version is published, or a later version of " + o.Name + " is.",
+			needs:       "builder_versions shows the version and why; builder_publish_again publishes it again once the cause is mended."})
+	}
+}
+
+// unread raises seat-outcome-unread about seat: what it said on subject is no outcome. read clears it.
+func (p *publishes) unread(ctx context.Context, seat, subject string, why error) {
+	p.findings.raise(ctx, finding{kind: versions.SeatOutcomeUnread, scope: health.ScopeModule, id: seat,
+		summary:     fmt.Sprintf("%s said on %s what is no outcome of a publish: %v", seat, subject, why),
+		headline:    "A registry seat said what the builder cannot read",
+		explanation: "The builder hears each registry seat's published, refused and removed to move a numbered version; this one does not read, so the version it was about does not move.",
+		resolved:    "The next outcome of " + seat + " reads.",
+		needs:       "a look at the seat's holder: the outcome's body is its contract's (mesh-contracts)."})
+}
+
+func (p *publishes) read(ctx context.Context, seat string) {
+	p.findings.clear(ctx, versions.SeatOutcomeUnread, health.ScopeModule, seat)
+}
+
+// ended is told each change of the state bounds: a bound whose time ended (the bus's marker) on a version still numbered
+// raises publish-unanswered.
+func (p *publishes) ended(ctx context.Context, e jetstream.KeyValueEntry) {
+	key, ok := versions.PublishBoundOf(e.Key())
+	if e.Operation() != jetstream.KeyValuePurge || !ok {
+		return
+	}
+	raw, _, found, err := p.versions.Store.Get(ctx, key)
+	if err != nil || !found {
+		return
+	}
+	v, err := versions.Decode(raw)
+	if err != nil || v.State != versions.Numbered {
+		return
+	}
+	p.unanswered(ctx, v, fmt.Sprintf("nothing within %s of its build", p.bound))
+}
+
+// watchBounds watches the state bounds, handing each change to each: a watch that cannot start loses every bound's end,
+// so it is the finding family-not-heard naming the state until a later start watches it (review round 2).
+func watchBounds(ctx context.Context, kv jetstream.KeyValue, each func(jetstream.KeyValueEntry), w heard.Writer, errs chan<- error, logf func(string, ...any)) {
+	const consequence = "a publish no holder answers, and a node holding the old form seven days, are not raised until the builder starts again"
+	pw, err := settle(ctx, kv, each)
+	if err != nil {
+		process.NotWatched(logf, versions.BoundsBucket, err, consequence)
+		w.NotHeard(versions.BoundsState, consequence, err)
+		return
+	}
+	w.Heard(versions.BoundsState)
+	go func() { errs <- follow(ctx, pw, each) }()
+}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/reads.go

@@ -0,0 +1,151 @@
+package main
+
+import (
+	"context"
+	"slices"
+	"sync"
+
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/process"
+
+	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun"
+	"git.novox.be/novox/mesh-delivery/sdk/enginereads"
+)
+
+// EngineReadsState is the builder's state of what each counted node's engine states it reads (novox/hq ADR 0618 §2, ADR
+// 0624 §1): one key `<node>`, written from the node-engine seat's verb manifest-reads at the builder's start, on the
+// seat's event manifest-reads-changed for that node, and when a person asks again (builder_engine_reads); a node that
+// is away keeps its last statement, and its key is removed when the placement no longer names the node. A counted node
+// with no key reads as stating the baseline: its first forms. No node's record is read in its place.
+const EngineReadsState = "engine-reads"
+
+// engineReadsBucket is that state's bucket.
+const engineReadsBucket = delivery.BuilderModule + "_" + EngineReadsState
+
+// engineReads keeps the statements and the counted nodes for the builder's forms (build.Builder.Forms).
+type engineReads struct {
+	keeper  *enginereads.Keeper
+	gate    *buildrun.ToolchainGate
+	mu      sync.Mutex
+	counted []string
+	// window is the old reference form's window over these statements (DLV-B9); nil keeps none.
+	window *oldForm
+	ctx    context.Context
+}
+
+// newEngineReads asks through call (process.Conn.CallOn) and keeps each answer in the state once it is bound.
+func newEngineReads(call enginereads.Caller, gate *buildrun.ToolchainGate, logf func(string, ...any)) *engineReads {
+	r := &engineReads{gate: gate, keeper: &enginereads.Keeper{Call: call, Logf: logf}}
+	r.keeper.Changed = r.stepWindow
+	return r
+}
+
+// stepWindow moves the old form's window to what the counted nodes state now (design 51 *Every build keeps the old
+// reference form*): on a statement's change, the placement's and a hand drop, and at each build key written.
+func (r *engineReads) stepWindow() {
+	if r.window == nil {
+		return
+	}
+	ctx := r.ctx
+	if ctx == nil {
+		ctx = context.Background()
+	}
+	_, counted := r.forms()
+	r.window.step(ctx, r.named(), counted)
+}
+
+// named are the nodes the placement names, none dropped: what the window's step judges a read by.
+func (r *engineReads) named() []string {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	return slices.Clone(r.counted)
+}
+
+// bind keeps the statements in kv and hears it: every node's last statement at the start, a person's ask again and drop
+// later. Bound once the state is on the bus (process.AwaitBucket).
+func (r *engineReads) bind(ctx context.Context, kv jetstream.KeyValue, errs chan<- error, logf func(string, ...any)) {
+	r.keeper.Put = func(node string, v []byte) error { _, err := kv.Put(ctx, node, v); return err }
+	r.keeper.Delete = func(node string) error { return kv.Delete(ctx, node) }
+	each := func(e jetstream.KeyValueEntry) {
+		r.keeper.Heard(e.Key(), e.Value(), e.Operation() != jetstream.KeyValuePut)
+	}
+	w, err := settle(ctx, kv, each)
+	if err != nil {
+		process.NotWatched(logf, engineReadsBucket, err, "builder_engine_reads is not answered until the builder starts again")
+		return
+	}
+	go func() { errs <- follow(ctx, w, each) }()
+	// Every counted node asked again, so what was asked before the state was bound is kept in it too.
+	r.mu.Lock()
+	nodes := slices.Clone(r.counted)
+	r.mu.Unlock()
+	for _, node := range nodes {
+		r.keeper.AskNode(node, "the state engine-reads is bound")
+	}
+}
+
+// placed takes the placement in: a node it names newly is asked, one it no longer names is forgotten, key and all. The
+// first call asks every counted node (the builder's start).
+func (r *engineReads) placed() {
+	nodes := r.gate.Nodes()
+	r.mu.Lock()
+	before, first := r.counted, r.counted == nil
+	r.counted = nodes
+	r.mu.Unlock()
+	for _, node := range nodes {
+		if first || !slices.Contains(before, node) {
+			r.keeper.AskNode(node, "counted: the placement names it")
+		}
+	}
+	for _, node := range before {
+		if !slices.Contains(nodes, node) {
+			r.keeper.Forget(node)
+		}
+	}
+	r.stepWindow()
+}
+
+// heard takes an event of the builder's consumer on EVENTS: manifest-reads-changed asks its node again, and answers true.
+func (r *engineReads) heard(m jetstream.Msg, logf func(string, ...any)) bool {
+	node, ours, err := enginereads.NodeOf(m.Subject(), m.Data())
+	if !ours {
+		return false
+	}
+	if ackErr := m.Ack(); ackErr != nil {
+		logf("acknowledging %s: %v", m.Subject(), ackErr)
+	}
+	if err != nil {
+		logf("%s holds what is not %s, and %s is asked again all the same: %v", m.Subject(), enginereads.Event, node, err)
+	}
+	r.keeper.AskNode(node, enginereads.Event)
+	return true
+}
+
+// forms is the counted nodes' statements, and those of the nodes whose engine answered; a retired node dropped by hand
+// (builder_old_form) counts no more.
+func (r *engineReads) forms() (present, counted map[string][]string) {
+	r.mu.Lock()
+	nodes := slices.Clone(r.counted)
+	r.mu.Unlock()
+	if r.window != nil {
+		dropped := r.window.dropped()
+		nodes = slices.DeleteFunc(nodes, func(n string) bool { return dropped[n] })
+	}
+	return r.keeper.Present(nodes), r.keeper.Reads(nodes)
+}
+
+// built is build.Builder.Forms: forms, and the window stepped with them, so a node's seven days are seen at the next
+// build key at the latest.
+func (r *engineReads) built() (present, counted map[string][]string) {
+	present, counted = r.forms()
+	if r.window != nil {
+		ctx := r.ctx
+		if ctx == nil {
+			ctx = context.Background()
+		}
+		r.window.step(ctx, r.named(), counted)
+	}
+	return present, counted
+}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/reasks.go

@@ -8,17 +8,21 @@ import (
 	"strings"
 	"time"
 
+	"git.novox.be/novox/mesh-sdk/go/buscompose"
+	"git.novox.be/novox/mesh-sdk/go/delivery"
 	"git.novox.be/novox/mesh-sdk/go/process"
 	"github.com/nats-io/nats.go"
 	"github.com/nats-io/nats.go/jetstream"
 
 	"mesh-delivery-builder/internal/build"
+	"mesh-delivery-builder/internal/versions"
 )
 
 // askAgainer is the part of the builder a reasks value asks through.
 type askAgainer interface {
 	AskAgain(key, why string) []string
 	BuildAgain(ctx context.Context, module, fp, why, by string, bound time.Duration) build.BuildAgainResult
+	AnnounceAgain(ctx context.Context, module, fp, why, by string) build.BuildAgainResult
 }
 
 // buildAgainBound is how long the builder waits for the claim and the asks of a key built again by hand; the tool waits
@@ -28,7 +32,7 @@ const buildAgainBound = 15 * time.Second
 // reAsked answers one value of the reasks state (the tool builder_ask_again, issue 1945): a value not yet answered asks the
 // key's waiting lanes again and is written back, by compare-and-set at its revision, with what the builder did. A value
 // answered already (this builder's own write) or deleted is left.
-func reAsked(ctx context.Context, b askAgainer, kv jetstream.KeyValue, e jetstream.KeyValueEntry, logf func(string, ...any)) {
+func reAsked(ctx context.Context, b askAgainer, acts versions.Acts, kv jetstream.KeyValue, e jetstream.KeyValueEntry, logf func(string, ...any)) {
 	if e.Operation() != jetstream.KeyValuePut {
 		return
 	}
@@ -45,6 +49,15 @@ func reAsked(ctx context.Context, b askAgainer, kv jetstream.KeyValue, e jetstre
 		go builtAgain(ctx, b, kv, e, r, logf)
 		return
 	}
+	if r.Mode == build.ModeAnnounce {
+		announcedAgain(ctx, b, kv, e, r, logf)
+		return
+	}
+	if r.Mode == build.ModePublishAgain || r.Mode == build.ModeFloorAgain || r.Mode == build.ModeOldFormDrop {
+		// A version's hand act (design 51 *Tools of the builder*) may build again, so it is answered beside the watch.
+		go versionActed(ctx, acts, kv, e, r, logf)
+		return
+	}
 	asked := b.AskAgain(e.Key(), r.Why)
 	if len(asked) == 0 {
 		r.Answer = "no ask of this key waits in this builder now (it is not building, or its build has not reached its ask yet): nothing was asked; builder_stuck shows where it stands"
@@ -65,21 +78,7 @@ func reAsked(ctx context.Context, b askAgainer, kv jetstream.KeyValue, e jetstre
 // emitAskedAgain says the builder's event build.asked-again (issue 1945): mesh.mod.<module>.event.build.asked-again,
 // with the SDK's envelope headers and the new ask's id as the bus's dedup id.
 func emitAskedAgain(ctx context.Context, js jetstream.JetStream, cred process.Account, e build.AskedAgain) error {
-	data, err := json.Marshal(e)
-	if err != nil {
-		return err
-	}
-	msg := nats.NewMsg(cred.EventSubject(build.AskedAgainEvent))
-	id := "asked-again-" + e.New
-	msg.Header.Set("x-event-id", id)
-	msg.Header.Set("x-source", cred.Module)
-	msg.Header.Set("x-node", cred.Node)
-	msg.Header.Set("x-time", time.Now().UTC().Format(time.RFC3339Nano))
-	msg.Header.Set("content-type", "application/json")
-	msg.Data = data
-	pub, cancel := context.WithTimeout(ctx, 10*time.Second)
-	defer cancel()
-	if _, err := js.PublishMsg(pub, msg, jetstream.WithMsgID(id)); err != nil {
+	if err := emitEvent(ctx, js, cred, build.AskedAgainEvent, "asked-again-"+e.New, e); err != nil {
 		return fmt.Errorf("saying %s for %s: %w", build.AskedAgainEvent, e.Key, err)
 	}
 	return nil
@@ -114,3 +113,75 @@ func builtAgain(ctx context.Context, b askAgainer, kv jetstream.KeyValue, e jets
 		logf("%s.%s: the answer could not be written: %v", build.ReAsksState, e.Key(), err)
 	}
 }
+
+// announcedAgain answers a reasks value of mode announce (the tool builder_announce_again): the done key is written again
+// unchanged, and the value is written back with the new revision, or why nothing was done.
+func announcedAgain(ctx context.Context, b askAgainer, kv jetstream.KeyValue, e jetstream.KeyValueEntry, r build.ReAsk, logf func(string, ...any)) {
+	res := b.AnnounceAgain(ctx, r.Module, r.FP, r.Why, r.By)
+	if res.Refused != "" {
+		r.Answer, r.Refused = res.Refused, true
+	} else {
+		r.Revision, r.Answer = res.Revision, fmt.Sprintf("announced again: the done key is written again, unchanged, as revision %d", res.Revision)
+	}
+	r.Answered = time.Now().UTC()
+	data, err := json.Marshal(r)
+	if err != nil {
+		return
+	}
+	if _, err := kv.Update(ctx, e.Key(), data, e.Revision()); err != nil && !errors.Is(err, jetstream.ErrKeyExists) && !errors.Is(err, jetstream.ErrKeyRevisionMismatch) {
+		logf("%s.%s: the answer could not be written: %v", build.ReAsksState, e.Key(), err)
+	}
+}
+
+// appendLog appends one entry to the builder's module log `build-log` (ADR 0297, ADR 0571 §1) under the module's key
+// (delivery.BuildLogKey), on the log's own subject: a module's program appends to the logs it keeps on its own credential.
+// The id makes a repeated append of one entry one entry.
+func appendLog(ctx context.Context, js jetstream.JetStream, cred process.Account, e delivery.BuildLogEntry) error {
+	data, err := delivery.EncodeBuildLogEntry(e)
+	if err != nil {
+		return err
+	}
+	key, err := delivery.BuildLogKey(e.Module)
+	if err != nil {
+		return err
+	}
+	msg := nats.NewMsg(buscompose.LogSubject(cred.Module, delivery.BuilderLog) + "." + key)
+	msg.Data = data
+	id := e.Event + "." + e.Module + "." + e.FP + "." + e.At.Format(time.RFC3339Nano)
+	pub, cancel := context.WithTimeout(ctx, 10*time.Second)
+	defer cancel()
+	if _, err := js.PublishMsg(pub, msg, jetstream.WithMsgID(id)); err != nil {
+		return fmt.Errorf("logging %s of %s at %s: %w", e.Event, e.Module, e.FP, err)
+	}
+	return nil
+}
+
+// versionActed answers a reasks value of builder_publish_again, builder_floor_again or builder_old_form's drop, a hand act said in the log.
+func versionActed(ctx context.Context, acts versions.Acts, kv jetstream.KeyValue, e jetstream.KeyValueEntry, r build.ReAsk, logf func(string, ...any)) {
+	var err error
+	if r.Mode == build.ModePublishAgain {
+		var ag versions.Again
+		ag, r.Answer, err = acts.PublishAgain(ctx, r.Name, r.FP, r.Why, r.By, r.At)
+		r.Do, r.Version = ag.Do, ag.Entry.Version
+	} else if r.Mode == build.ModeOldFormDrop {
+		if acts.DropOldForm == nil {
+			err = errors.New("this builder keeps no old-form window")
+		} else {
+			r.Answer, err = acts.DropOldForm(ctx, r.Name, r.By, r.Why, r.At)
+		}
+	} else {
+		r.Answer, err = acts.FloorAgain(ctx, r.Name)
+	}
+	if err != nil {
+		r.Answer, r.Refused = err.Error(), true
+	}
+	r.Answered = time.Now().UTC()
+	logf("%s: %s of %s by %s (%s): %s", e.Key(), r.Mode, r.Name, r.By, r.Why, r.Answer)
+	data, err := json.Marshal(r)
+	if err != nil {
+		return
+	}
+	if _, err := kv.Update(ctx, e.Key(), data, e.Revision()); err != nil && !errors.Is(err, jetstream.ErrKeyExists) && !errors.Is(err, jetstream.ErrKeyRevisionMismatch) {
+		logf("%s.%s: the answer could not be written: %v", build.ReAsksState, e.Key(), err)
+	}
+}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/refused_test.go

@@ -0,0 +1,528 @@
+package main
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"log"
+	"maps"
+	"slices"
+	"strings"
+	"testing"
+	"time"
+
+	"git.novox.be/novox/mesh-sdk/go/health"
+
+	"git.novox.be/novox/mesh-delivery/sdk/heard"
+	"git.novox.be/novox/mesh-sdk/go/process"
+
+	"github.com/nats-io/nats.go"
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-contracts/go/seats/nodeengine"
+	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun"
+	"git.novox.be/novox/mesh-delivery/sdk/enginereads"
+	"git.novox.be/novox/mesh-delivery/sdk/forms"
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+
+	"mesh-delivery-builder/internal/build"
+	"mesh-delivery-builder/internal/versions"
+)
+
+// 1945 (a part exits at start for a bucket it works without): a bus that refuses every toolchains bucket leaves the
+// watch unstarted and the part running, said; a refused bucket it cannot work without is an error naming the bucket and
+// its grant. The gate over the seat's placement, and its refusal, are mesh-sdk's (buildrun.ToolchainGate,
+// issue 774).
+func TestARefusedBucketIsSaidAndThePartGoesOn(t *testing.T) {
+	t.Run("a floor's wake is heard on the events consumer (design 51 The floor)", aFloorsWakeIsHeard)
+	t.Run("a failed trunk build is a finding until a later done one (DLV-B7)", aFailedTrunkBuildIsAFinding)
+	t.Run("a branch's end is acknowledged once its tagged versions are removed (design 51 Tagged versions)", aBranchsEndIsHeard)
+	set := &buildrun.ToolchainSet{}
+	var logs bytes.Buffer
+	logger := log.New(&logs, "", 0)
+	refused := refusingBus{err: errors.New("nats: permissions violation for publish to $JS.API.CONSUMER.CREATE.KV_mesh-build-node_toolchains")}
+	if err := newToolchainWatch(context.Background(), refusingBus{refuseOpen: true, err: refused.err}, set, func(context.Context) {}, logger).start(); err != nil {
+		t.Errorf("a refused toolchains bucket stopped the start: %v", err)
+	}
+	if !strings.Contains(logs.String(), "cannot be read") {
+		t.Errorf("the refusals were not said: %q", logs.String())
+	}
+	if _, err := process.EssentialBucket(context.Background(), refusingBus{refuseOpen: true, err: refused.err}, "builder", "mesh-delivery-indexer_modules", "work"); err == nil ||
+		!strings.Contains(err.Error(), "grant of mesh-delivery-indexer_modules") {
+		t.Errorf("a refused bucket the part needs: %v, want an error naming its grant", err)
+	}
+	// The gate's source (the previews' trunk heads): refused at start, the builder goes on, and a candidate asking a trunk
+	// head is told why and opens it again then.
+	src := &trunkSource{ctx: context.Background(), js: refusingBus{refuseOpen: true, err: refused.err}, heads: &sourceHeads{}, errs: make(chan error, 1), logf: logger.Printf}
+	src.start()
+	if _, err := src.head(context.Background(), 7, "novox/mesh-catalog"); err == nil || !strings.Contains(err.Error(), delivery.SourceBucket) {
+		t.Errorf("a trunk head with the source refused: %v, want why", err)
+	}
+	if src.opened {
+		t.Error("a refused source counts as opened, so it is never opened again")
+	}
+	t.Run("ADR 0624: the counted nodes' engine reads", theCountedNodesEngineReads)
+}
+
+// theCountedNodesEngineReads: the builder asks the node-engine seat's verb of every node the placement names; a node away
+// and never asked has no statement and reads as the baseline's first forms, with no node record read in its place; an
+// away node keeps its last statement; a node the placement no longer names leaves the count, its key removed; and
+// builder_engine_reads drops one node's key.
+func theCountedNodesEngineReads(t *testing.T) {
+	gate := buildrun.NewToolchainGate(nil, func(string, string, []byte, bool) bool { return false }, t.Logf)
+	place := func(nodes ...string) {
+		for _, node := range []string{"n1", "n2"} {
+			pl := delivery.Placement{Node: node}
+			if slices.Contains(nodes, node) {
+				pl.Modules = []delivery.PlacedModule{{Module: "web"}}
+			}
+			values, err := delivery.PlacementValues(pl)
+			if err != nil {
+				t.Fatal(err)
+			}
+			for key, raw := range values {
+				gate.Placement(key, raw, false, time.Now())
+			}
+			if !slices.Contains(nodes, node) {
+				key, _ := delivery.PlacementModuleKey(node, "web")
+				gate.Placement(key, nil, true, time.Now())
+			}
+		}
+	}
+	away := map[string]bool{"n2": true}
+	asked := map[string]int{}
+	r := newEngineReads(func(node, key string, _ any) (json.RawMessage, error) {
+		asked[node]++
+		if away[node] {
+			return nil, nats.ErrNoResponders
+		}
+		return json.Marshal(nodeengine.ManifestReadsAnswer{V: 1, Node: node, ManifestReads: []string{"form:new"}, StatedAt: time.Now().Format(time.RFC3339Nano)})
+	}, gate, t.Logf)
+	r.keeper.Sync = true
+	kept := map[string][]byte{}
+	r.keeper.Put = func(node string, v []byte) error { kept[node] = v; return nil }
+	r.keeper.Delete = func(node string) error { delete(kept, node); return nil }
+	place("n1", "n2")
+	r.placed()
+	present, counted := r.forms()
+	if !slices.Equal(present["n1"], []string{"form:new"}) || len(present) != 1 || len(counted) != 2 || counted["n2"] != nil {
+		t.Errorf("away and never asked: present %v, counted %v", present, counted)
+	}
+	if s := r.keeper.Statements()["n2"]; s.From != enginereads.FromNone || s.Answered || asked["n2"] != 1 {
+		t.Errorf("n2, away and never asked, is %+v (asked %d)", s, asked["n2"])
+	}
+	// n2 back, stating {word:module}, then away again: it keeps that statement.
+	away["n2"] = false
+	r.keeper.Heard("n2", mustStatement(t, enginereads.Statement{Node: "n2", From: enginereads.FromVerb, Answered: true,
+		AskAgain: &enginereads.Again{By: "n1.ada", Why: "back"}}), false)
+	away["n2"] = true
+	r.keeper.AskNode("n2", "its event")
+	if _, counted = r.forms(); !slices.Equal(counted["n2"], []string{"form:new"}) || r.keeper.Statements()["n2"].Answered {
+		t.Errorf("away again, n2 reads %v (%+v)", counted["n2"], r.keeper.Statements()["n2"])
+	}
+	// n2 retired: it leaves the placement, and its key goes.
+	place("n1")
+	r.placed()
+	if _, counted = r.forms(); len(counted) != 1 || kept["n2"] != nil {
+		t.Errorf("retired n2: counted %v, its key %s", counted, kept["n2"])
+	}
+	// builder_engine_reads drops one key.
+	st := &memReads{v: map[string][]byte{"n1": kept["n1"]}}
+	tool := enginereads.Tool("builder_engine_reads", "the builder", st, true, time.Now)
+	if _, err := tool.Run(map[string]any{"node": "n1", "drop": "true", "why": "a test"}); err != nil || st.v["n1"] != nil {
+		t.Errorf("drop: %v, the key %s", err, st.v["n1"])
+	}
+}
+
+func mustStatement(t *testing.T, s enginereads.Statement) []byte {
+	t.Helper()
+	raw, err := enginereads.Encode(s)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return raw
+}
+
+// memReads is the builder's state of engine reads in memory, as the tool reads it.
+type memReads struct{ v map[string][]byte }
+
+func (m *memReads) Keys() ([]string, error) { return slices.Collect(maps.Keys(m.v)), nil }
+func (m *memReads) Get(key string) ([]byte, uint64, bool, error) {
+	v, ok := m.v[key]
+	return v, 1, ok, nil
+}
+func (m *memReads) Put(key string, value []byte) (uint64, error) { m.v[key] = value; return 2, nil }
+func (m *memReads) Delete(key string) error                      { delete(m.v, key); return nil }
+func (m *memReads) Await(string, uint64, func([]byte) bool, time.Duration) ([]byte, error) {
+	return nil, errors.New("no part answers here")
+}
+
+// refusingBus is a bus that refuses: every open (refuseOpen), or every watch of a bucket it opens, with err.
+type refusingBus struct {
+	refuseOpen bool
+	err        error
+}
+
+func (r refusingBus) KeyValue(context.Context, string) (jetstream.KeyValue, error) {
+	if r.refuseOpen {
+		return nil, r.err
+	}
+	return refusedWatch{err: r.err}, nil
+}
+
+type refusedWatch struct {
+	jetstream.KeyValue
+	err error
+}
+
+func (r refusedWatch) WatchAll(context.Context, ...jetstream.WatchOpt) (jetstream.KeyWatcher, error) {
+	return nil, r.err
+}
+func (r refusedWatch) Watch(context.Context, string, ...jetstream.WatchOpt) (jetstream.KeyWatcher, error) {
+	return nil, r.err
+}
+
+// wakeMsg is a message of the builder's events consumer: its subject and body, acknowledged.
+type wakeMsg struct {
+	jetstream.Msg
+	subject string
+	data    []byte
+	acked   bool
+	naked   bool
+	delayed time.Duration
+}
+
+func (m *wakeMsg) Subject() string { return m.subject }
+func (m *wakeMsg) Data() []byte    { return m.data }
+func (m *wakeMsg) Ack() error      { m.acked = true; return nil }
+func (m *wakeMsg) Nak() error      { m.naked = true; return nil }
+func (m *wakeMsg) NakWithDelay(d time.Duration) error {
+	m.delayed = d
+	return nil
+}
+func (m *wakeMsg) Metadata() (*jetstream.MsgMetadata, error) {
+	return nil, errors.New("no metadata")
+}
+func (m *wakeMsg) Headers() nats.Header {
+	return nil
+}
+
+func aFloorsWakeIsHeard(t *testing.T) {
+	var logs bytes.Buffer
+	waits := &versions.FloorWaits{}
+	waits.Wait("m/lib", versions.SeatGoPackages, "", versions.Floor{Silent: []string{versions.SourceRequirements}}, nil, time.Unix(0, 0))
+	waits.Wait("m/img", versions.SeatImages, "", versions.Floor{Silent: []string{versions.SourceTags}}, nil, time.Unix(0, 0))
+	f := &floorWake{b: &build.Builder{}, waits: waits, logf: log.New(&logs, "", 0).Printf}
+	accepted := &wakeMsg{subject: manifestAcceptedSubject}
+	if !f.heard(context.Background(), accepted) || !accepted.acked || !strings.Contains(logs.String(), "the floor of m/lib is asked again: manifest-accepted") {
+		t.Fatalf("manifest-accepted: acked %v, log %q", accepted.acked, logs.String())
+	}
+	logs.Reset()
+	cleared := &wakeMsg{subject: conditionClearedSubject, data: []byte(`{"subject":{"scope":"probe","id":"ace/mesh-delivery-forge-bridge"}}`)}
+	if !f.heard(context.Background(), cleared) || !strings.Contains(logs.String(), "the floor of m/img is asked again: condition-cleared") {
+		t.Fatalf("condition-cleared: log %q", logs.String())
+	}
+	if f.heard(context.Background(), &wakeMsg{subject: delivery.ArtifactsGoneSubject}) {
+		t.Fatal("artifacts-gone was taken as a floor's wake")
+	}
+	// DLV-B4: a registry seat's outcome on the same consumer moves a version; a published wakes a name whose seat was
+	// silent; one the state cannot take is left for the bus to give again.
+	logs.Reset()
+	waits.Wait("m/pkg", versions.SeatGoPackages, "", versions.Floor{Silent: []string{versions.SourceSeat}}, nil, time.Unix(0, 0))
+	h := &seatHearer{n: &versions.Numberer{Versions: versions.Versions{Store: noVersions{}}, Waits: waits}, b: &build.Builder{}, logf: log.New(&logs, "", 0).Printf}
+	byDigest := &wakeMsg{subject: "mesh.seat.go-package-registry.event.published", data: []byte(`{"name":"m/other","digest":"sha256:aa","kind":"package","holder":"gitea"}`)}
+	if !h.heard(context.Background(), byDigest) || !byDigest.acked || !strings.Contains(logs.String(), "the floor of m/pkg is asked again: go-package-registry said published") {
+		t.Fatalf("published: acked %v, log %q", byDigest.acked, logs.String())
+	}
+	refused := &wakeMsg{subject: "mesh.seat.oci-artifact-registry.event.refused", data: []byte(`{"name":"m/program","version":"0.1.3","digest":"sha256:bb","reason":"bytes differ"}`)}
+	if !h.heard(context.Background(), refused) || refused.acked || !refused.naked {
+		t.Fatalf("a refusal the state cannot take: acked %v, naked %v, log %q", refused.acked, refused.naked, logs.String())
+	}
+	if h.heard(context.Background(), &wakeMsg{subject: manifestAcceptedSubject}) {
+		t.Fatal("manifest-accepted was taken as a seat's outcome")
+	}
+}
+
+// noVersions is a state versions that holds nothing.
+type noVersions struct{}
+
+func (noVersions) Get(context.Context, string) ([]byte, uint64, bool, error) {
+	return nil, 0, false, nil
+}
+func (noVersions) Create(context.Context, string, []byte) (uint64, error) {
+	return 0, errors.New("read only")
+}
+func (noVersions) Update(context.Context, string, []byte, uint64) (uint64, error) {
+	return 0, errors.New("read only")
+}
+func (noVersions) KeysOf(context.Context, string) ([]string, error) { return nil, nil }
+
+func aBranchsEndIsHeard(t *testing.T) {
+	for _, c := range []struct {
+		f    forgeEnd
+		want bool
+	}{
+		{forgeEnd{Kind: delivery.ForgeMerged, Repository: "o/r", Branch: "feat/x"}, true},
+		{forgeEnd{Kind: forgeBranchDeleted, Repository: "o/r", Branch: "feat/x"}, true},
+		{forgeEnd{Kind: delivery.ForgePull, Repository: "o/r", Branch: "feat/x", Action: delivery.PullClosed}, true},
+		{forgeEnd{Kind: delivery.ForgePull, Repository: "o/r", Branch: "feat/x", Action: delivery.PullOpened}, false},
+		{forgeEnd{Kind: delivery.ForgeMerged, Repository: "o/r"}, false},
+	} {
+		if got := c.f.ended(); got != c.want {
+			t.Errorf("%+v ended = %v, want %v", c.f, got, c.want)
+		}
+	}
+	var logs bytes.Buffer
+	woken := 0
+	h := &branchEnds{acts: versions.Acts{Numberer: &versions.Numberer{Versions: versions.Versions{Store: noVersions{}}}}, findings: &findings{logf: t.Logf},
+		tagAsks: func() jetstream.KeyValue { return nil }, wake: func(context.Context) { woken++ }, logf: log.New(&logs, "", 0).Printf, now: time.Now}
+	open := &wakeMsg{subject: "mesh.mod.mesh-delivery-forge-bridge.event.forge.o.r.pull", data: []byte(`{"kind":"pull","repository":"o/r","branch":"feat/x","action":"opened"}`)}
+	h.heard(context.Background(), open)
+	merged := &wakeMsg{subject: "mesh.mod.mesh-delivery-forge-bridge.event.forge.o.r.merged", data: []byte(`{"kind":"merged","repository":"o/r","branch":"feat/x"}`)}
+	h.heard(context.Background(), merged)
+	if !open.acked || !merged.acked || woken != 2 {
+		t.Errorf("an open pull acked %v, a merge with nothing tagged acked %v, floors woken %d times", open.acked, merged.acked, woken)
+	}
+	// The checker's family holds its verdicts beside tag-wanted: a verdict is acknowledged and not kept; a tag-wanted with
+	// tag-asks not bound is heard again.
+	verdict := &wakeMsg{subject: "mesh.stream.mesh-delivery-checker.event.verdict", data: []byte(`{"repository":"o/r"}`)}
+	wanted := &wakeMsg{subject: tagWantedSubject, data: []byte(`{"repository":"o/r","branch":"feat/x","head":"abc","tag":"feat-x"}`)}
+	for _, m := range []*wakeMsg{verdict, wanted} {
+		tagWanted(context.Background(), nil, m, delivery.CheckerModule, time.Now(), t.Logf)
+	}
+	if !verdict.acked || verdict.delayed != 0 || wanted.acked || wanted.delayed != versions.RemoveAgainAfter || !strings.HasPrefix(tagWantedSubject, "mesh.stream.") {
+		t.Errorf("a verdict acked %v (delayed %v), a tag-wanted acked %v (delayed %v)", verdict.acked, verdict.delayed, wanted.acked, wanted.delayed)
+	}
+	unreadable := &wakeMsg{subject: merged.subject, data: merged.data}
+	h.acts.Numberer.Versions.Store = failingVersions{}
+	h.heard(context.Background(), unreadable)
+	if unreadable.acked || unreadable.delayed != versions.RemoveAgainAfter {
+		t.Errorf("a branch's end the versions cannot answer: acked %v, given again after %v", unreadable.acked, unreadable.delayed)
+	}
+}
+
+// failingVersions is a state versions that cannot be read.
+type failingVersions struct{ noVersions }
+
+func (failingVersions) KeysOf(context.Context, string) ([]string, error) {
+	return nil, errors.New("down")
+}
+
+func aFailedTrunkBuildIsAFinding(t *testing.T) {
+	st := &memFindings{vals: map[string][]byte{}}
+	f := &findings{store: st, logf: t.Logf, now: func() time.Time { return time.Unix(0, 0) }}
+	ended := func(outcome, ref string) delivery.BuildLogEntry {
+		return delivery.BuildLogEntry{Event: delivery.BuildEndedEvent, Module: "m", FP: "f1", Commit: "c", Ref: ref, Outcome: outcome}
+	}
+	key := health.FindingKey(health.ScopeModule, "m", BuildFailed)
+	f.buildEnded(context.Background(), ended(delivery.BuildFailed, "refs/pull/3/head"))
+	if len(st.vals) != 0 {
+		t.Fatalf("a candidate's failed build is a finding: %v", st.vals)
+	}
+	f.buildEnded(context.Background(), ended(delivery.BuildFailed, ""))
+	got, err := health.DecodeFinding(st.vals[key])
+	if err != nil || got.Observer != delivery.BuilderModule || !strings.Contains(got.Summary, "trunk build of m at f1") {
+		t.Fatalf("the finding = %+v, %v", got, err)
+	}
+	f.buildEnded(context.Background(), ended(delivery.BuildDone, ""))
+	if _, ok := st.vals[key]; ok {
+		t.Error("a later done trunk build leaves build-failed")
+	}
+	// The floor finding: raised while a name waits on its floor, cleared once it is known.
+	fw := &versions.FloorWaits{Said: f.floorSaid(context.Background())}
+	fw.Wait("m/lib", versions.SeatGoPackages, "", versions.Floor{Silent: []string{versions.SourceTags}}, nil, time.Unix(0, 0))
+	floorKey := health.FindingKey(health.ScopeModule, "m/lib", versions.FloorSilent)
+	if got, err := health.DecodeFinding(st.vals[floorKey]); err != nil || !strings.Contains(got.Summary, "bridge_tags did not answer") {
+		t.Fatalf("the floor finding = %+v, %v", got, err)
+	}
+	fw.Answered("m/lib")
+	if _, ok := st.vals[floorKey]; ok {
+		t.Error("a known floor leaves floor-silent")
+	}
+	// Design 51 *Health and conditions* (review round 1): a holder's refused is publish-refused with its reason, a version
+	// no holder answered within its bound publish-unanswered, a seat's outcome that does not read seat-outcome-unread;
+	// a later published of the name clears the first two, the seat's next outcome that reads the third.
+	vs := versions.Versions{Store: memVersions{}}
+	for _, v := range []string{"0.1.3", "0.1.4"} {
+		raw, err := versions.Encode(versions.Entry{Name: "m/program", Kind: versions.KindBundle, Series: "0.1", Version: v, Seat: "oci-artifact-registry", State: versions.Numbered})
+		if err != nil {
+			t.Fatal(err)
+		}
+		vs.Store.(memVersions)[versions.Key("m/program", v)] = raw
+	}
+	pubs := &publishes{bounds: func() jetstream.KeyValue { return nil }, versions: vs, findings: f, bound: versions.PublishBound, logf: t.Logf}
+	h := &seatHearer{n: &versions.Numberer{Versions: vs}, b: &build.Builder{}, logf: t.Logf, pub: pubs}
+	refusedKey := health.FindingKey(health.ScopeModule, "m/program", versions.PublishRefused)
+	refused := &wakeMsg{subject: "mesh.seat.oci-artifact-registry.event.refused", data: []byte(`{"name":"m/program","version":"0.1.3","digest":"sha256:bb","reason":"bytes differ"}`)}
+	if !h.heard(context.Background(), refused) || !refused.acked {
+		t.Fatalf("a refusal: acked %v", refused.acked)
+	}
+	if got, err := health.DecodeFinding(st.vals[refusedKey]); err != nil || !strings.Contains(got.Summary, "refused to publish m/program@0.1.3") || !strings.Contains(got.Summary, "bytes differ") {
+		t.Fatalf("a holder's refused: the finding = %+v, %v", got, err)
+	}
+	pubs.ended(context.Background(), purged{key: versions.PublishBoundKey("m/program", "0.1.4")})
+	unansweredKey := health.FindingKey(health.ScopeModule, "m/program", versions.PublishUnanswered)
+	if got, err := health.DecodeFinding(st.vals[unansweredKey]); err != nil || !strings.Contains(got.Summary, "neither published nor refused of m/program@0.1.4") {
+		t.Fatalf("a bound ended unanswered: the finding = %+v, %v", got, err)
+	}
+	// Review round 2: a bound that cannot be written is publish-unanswered at once; a watch of bounds that cannot start
+	// is family-not-heard naming the state.
+	delete(st.vals, unansweredKey)
+	pubs.arm(context.Background(), versions.Entry{Name: "m/program", Version: "0.1.4", Seat: "oci-artifact-registry"})
+	if got, err := health.DecodeFinding(st.vals[unansweredKey]); err != nil || !strings.Contains(got.Summary, "its bound could not be written") {
+		t.Fatalf("a bound not written: the finding = %+v, %v", got, err)
+	}
+	watchBounds(context.Background(), refusedWatch{err: errors.New("permissions violation")}, func(jetstream.KeyValueEntry) {}, f.notHeard(context.Background()), nil, t.Logf)
+	if got, err := health.DecodeFinding(st.vals[heard.Key(delivery.BuilderModule, versions.BoundsState)]); err != nil || !strings.Contains(got.Summary, "permissions violation") {
+		t.Fatalf("bounds not watched: the finding = %+v, %v", got, err)
+	}
+	delete(st.vals, heard.Key(delivery.BuilderModule, versions.BoundsState))
+	malformed := &wakeMsg{subject: "mesh.seat.oci-artifact-registry.event.published", data: []byte(`{"version":"0.1.4"}`)}
+	unreadKey := health.FindingKey(health.ScopeModule, "oci-artifact-registry", versions.SeatOutcomeUnread)
+	if !h.heard(context.Background(), malformed) || !malformed.acked || st.vals[unreadKey] == nil {
+		t.Fatalf("an outcome that does not read: acked %v, findings %v", malformed.acked, st.vals)
+	}
+	published := &wakeMsg{subject: "mesh.seat.oci-artifact-registry.event.published", data: []byte(`{"name":"m/program","version":"0.1.4","digest":"sha256:cc"}`)}
+	if !h.heard(context.Background(), published) || st.vals[refusedKey] != nil || st.vals[unansweredKey] != nil || st.vals[unreadKey] != nil {
+		t.Fatalf("a later published leaves the findings: %v", st.vals)
+	}
+	// ADR 0615 §5 (review round 1): a consumer not there yet is family-not-heard naming its stream, cleared when it binds.
+	notHeard := f.notHeard(context.Background())
+	unheardKey := heard.Key(delivery.BuilderModule, "FORGE")
+	_ = notHeard.Bind("FORGE", "a branch's end is not heard", func() error { return errors.New("consumer not found") })
+	if got, err := health.DecodeFinding(st.vals[unheardKey]); err != nil || got.Kind != heard.Kind || !strings.Contains(got.Summary, "does not hear FORGE") {
+		t.Fatalf("a consumer not there: the finding = %+v, %v", got, err)
+	}
+	_ = notHeard.Bind("FORGE", "a branch's end is not heard", func() error { return nil })
+	if _, ok := st.vals[unheardKey]; ok {
+		t.Error("a consumer bound leaves family-not-heard")
+	}
+	// DLV-B9, the old form's window: one counted node reading only the first form holds it; seven days on it is
+	// old-form-held about that node; the node stating the newest form closes it, said once, the finding cleared; a
+	// retired node dropped by hand leaves the count.
+	now := time.Unix(0, 0)
+	fs := forms.ArtifactForms{{Name: "registry", First: true, Kinds: []string{"image"}}, {Name: "oci", Kinds: []string{"image"}}}
+	var closings []versions.OldFormClosedBody
+	var logged []delivery.BuildLogEntry
+	marks := &memBounds{keys: map[string]bool{}}
+	window := &oldForm{forms: fs, findings: f, logf: t.Logf, now: func() time.Time { return now }, bounds: func() jetstream.KeyValue { return marks },
+		said: func(b versions.OldFormClosedBody) { closings = append(closings, b) },
+		log:  func(e delivery.BuildLogEntry) { logged = append(logged, e) }}
+	reads := &engineReads{keeper: &enginereads.Keeper{}, window: window, counted: []string{"a", "b"}}
+	newest := []string{forms.FormNeed("oci")}
+	counted := map[string][]string{"a": newest, "b": nil}
+	window.step(context.Background(), []string{"a", "b"}, counted)
+	heldKey := health.FindingKey(health.ScopeMachine, "b", versions.OldFormHeld)
+	if !window.w.Open || !slices.Equal(window.w.Holding, []string{"b"}) || st.vals[heldKey] != nil {
+		t.Fatalf("one node lacking the newest form: %+v", window.w)
+	}
+	// Review round 1: the node holding it has a bound in the state bounds ending at its seven days, so old-form-held is
+	// raised then, not at the next change.
+	if !marks.keys[versions.OldFormBoundKey("b")] || marks.keys[versions.OldFormBoundKey("a")] {
+		t.Fatalf("the old form's bounds = %v, want b's alone", marks.keys)
+	}
+	// Security-upgrade F3 (review round 1): an empty node_haves read, naming no node, leaves the window open.
+	window.step(context.Background(), nil, map[string][]string{})
+	if !window.w.Open || !slices.Equal(window.w.Holding, []string{"b"}) || len(closings) != 0 {
+		t.Fatalf("an empty read closed the window: %+v, closings %+v", window.w, closings)
+	}
+	now = now.Add(versions.FindingAfter)
+	window.step(context.Background(), []string{"a", "b"}, counted)
+	if got, err := health.DecodeFinding(st.vals[heldKey]); err != nil || !strings.Contains(got.Summary, "the node-engine of b") {
+		t.Fatalf("seven days held: the finding = %+v, %v", got, err)
+	}
+	counted["b"] = newest
+	window.step(context.Background(), []string{"a", "b"}, counted)
+	window.step(context.Background(), []string{"a", "b"}, counted)
+	if marks.keys[versions.OldFormBoundKey("b")] {
+		t.Error("a node no longer holding the window keeps its bound")
+	}
+	if window.w.Open || len(closings) != 1 || !slices.Equal(closings[0].LastHolding, []string{"b"}) || st.vals[heldKey] != nil {
+		t.Errorf("the node back with the newest form: %+v, closings %+v, finding left %v", window.w, closings, st.vals[heldKey] != nil)
+	}
+	if len(logged) != 1 || logged[0].Event != delivery.BuildSaidEvent || logged[0].Why != versions.SaidOldFormClosed ||
+		!strings.Contains(logged[0].Line, "last held by b") {
+		t.Errorf("the build log = %+v, want the close said once (build.said)", logged)
+	} else if _, err := delivery.EncodeBuildLogEntry(logged[0]); err != nil {
+		t.Errorf("the close is no entry the build log takes: %v", err)
+	}
+	if _, err := window.drop(context.Background(), "b", "op@shanks", "retired", now); err != nil {
+		t.Fatal(err)
+	}
+	if _, c := reads.forms(); len(c) != 1 || c["b"] != nil {
+		t.Errorf("a node dropped by hand is still counted: %v", c)
+	}
+}
+
+// memVersions is a state versions in memory.
+type memVersions map[string][]byte
+
+func (m memVersions) Get(_ context.Context, key string) ([]byte, uint64, bool, error) {
+	v, ok := m[key]
+	return v, 1, ok, nil
+}
+func (m memVersions) Create(_ context.Context, key string, v []byte) (uint64, error) {
+	m[key] = v
+	return 1, nil
+}
+func (m memVersions) Update(_ context.Context, key string, v []byte, _ uint64) (uint64, error) {
+	m[key] = v
+	return 2, nil
+}
+func (m memVersions) KeysOf(context.Context, string) ([]string, error) {
+	return slices.Collect(maps.Keys(m)), nil
+}
+
+// memBounds is the state bounds in memory: which keys stand.
+type memBounds struct {
+	jetstream.KeyValue
+	keys map[string]bool
+}
+
+func (m *memBounds) Create(_ context.Context, key string, _ []byte, _ ...jetstream.KVCreateOpt) (uint64, error) {
+	if m.keys[key] {
+		return 0, jetstream.ErrKeyExists
+	}
+	m.keys[key] = true
+	return 1, nil
+}
+func (m *memBounds) Delete(_ context.Context, key string, _ ...jetstream.KVDeleteOpt) error {
+	delete(m.keys, key)
+	return nil
+}
+
+// purged is the bus's marker of a key whose time to live ended.
+type purged struct {
+	jetstream.KeyValueEntry
+	key string
+}
+
+func (p purged) Key() string                     { return p.key }
+func (p purged) Operation() jetstream.KeyValueOp { return jetstream.KeyValuePurge }
+
+// memFindings is a findings bucket in memory.
+type memFindings struct{ vals map[string][]byte }
+
+type memEntry struct {
+	jetstream.KeyValueEntry
+	v []byte
+}
+
+func (e memEntry) Value() []byte { return e.v }
+
+func (m *memFindings) Get(_ context.Context, key string) (jetstream.KeyValueEntry, error) {
+	v, ok := m.vals[key]
+	if !ok {
+		return nil, jetstream.ErrKeyNotFound
+	}
+	return memEntry{v: v}, nil
+}
+func (m *memFindings) Put(_ context.Context, key string, v []byte) (uint64, error) {
+	m.vals[key] = v
+	return 1, nil
+}
+func (m *memFindings) Delete(_ context.Context, key string, _ ...jetstream.KVDeleteOpt) error {
+	delete(m.vals, key)
+	return nil
+}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/seats.go

@@ -0,0 +1,148 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"strings"
+
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-contracts/go/seats/containerimageregistry"
+	"git.novox.be/novox/mesh-contracts/go/seats/gopackageregistry"
+	"git.novox.be/novox/mesh-contracts/go/seats/npmpackageregistry"
+	"git.novox.be/novox/mesh-contracts/go/seats/ociartifactregistry"
+
+	"mesh-delivery-builder/internal/build"
+	"mesh-delivery-builder/internal/versions"
+)
+
+// seatEvent is one registry seat's event the builder hears: the seat and the event's name.
+type seatEvent struct{ seat, event string }
+
+// seatEvents are the four registry seats' published, refused, removed and kept, by subject (design 51 *How a publish ends*,
+// DLV-B4): each a seat event `<seat>.<event>` on the shared events stream, heard on the builder's durable consumer of
+// it through the manifest's consumes. The subjects are the seats' contracts' (mesh-contracts).
+var seatEvents = map[string]seatEvent{
+	containerimageregistry.SubjectPublished: {containerimageregistry.Seat, containerimageregistry.EventPublished},
+	containerimageregistry.SubjectRefused:   {containerimageregistry.Seat, containerimageregistry.EventRefused},
+	containerimageregistry.SubjectRemoved:   {containerimageregistry.Seat, containerimageregistry.EventRemoved},
+	containerimageregistry.SubjectKept:      {containerimageregistry.Seat, containerimageregistry.EventKept},
+	ociartifactregistry.SubjectPublished:    {ociartifactregistry.Seat, ociartifactregistry.EventPublished},
+	ociartifactregistry.SubjectRefused:      {ociartifactregistry.Seat, ociartifactregistry.EventRefused},
+	ociartifactregistry.SubjectRemoved:      {ociartifactregistry.Seat, ociartifactregistry.EventRemoved},
+	ociartifactregistry.SubjectKept:         {ociartifactregistry.Seat, ociartifactregistry.EventKept},
+	gopackageregistry.SubjectPublished:      {gopackageregistry.Seat, gopackageregistry.EventPublished},
+	gopackageregistry.SubjectRefused:        {gopackageregistry.Seat, gopackageregistry.EventRefused},
+	gopackageregistry.SubjectRemoved:        {gopackageregistry.Seat, gopackageregistry.EventRemoved},
+	gopackageregistry.SubjectKept:           {gopackageregistry.Seat, gopackageregistry.EventKept},
+	npmpackageregistry.SubjectPublished:     {npmpackageregistry.Seat, npmpackageregistry.EventPublished},
+	npmpackageregistry.SubjectRefused:       {npmpackageregistry.Seat, npmpackageregistry.EventRefused},
+	npmpackageregistry.SubjectRemoved:       {npmpackageregistry.Seat, npmpackageregistry.EventRemoved},
+	npmpackageregistry.SubjectKept:          {npmpackageregistry.Seat, npmpackageregistry.EventKept},
+}
+
+// seatHearer takes the registry seats' outcomes in: each moves a numbered version (versions.Numberer.Heard), and a
+// `published` that wakes a name waiting on its floor looks at every module again.
+type seatHearer struct {
+	n    *versions.Numberer
+	b    *build.Builder
+	logf func(string, ...any)
+	// pub raises and clears the findings of a publish that ended badly; nil raises none.
+	pub *publishes
+}
+
+// heard takes a message of the events consumer in when it is a registry seat's outcome, and answers whether it was.
+// One the state could not take is left unacknowledged (Nak), so the bus gives it again; one that is no outcome is said
+// and dropped.
+func (h *seatHearer) heard(ctx context.Context, m jetstream.Msg) bool {
+	se, ok := seatEvents[m.Subject()]
+	if !ok {
+		return false
+	}
+	var o versions.Outcome
+	if err := json.Unmarshal(m.Data(), &o); err != nil || o.Name == "" {
+		if err == nil {
+			err = errors.New("it names no name")
+		}
+		h.logf("%s holds what is no outcome of %s, left: %v", m.Subject(), se.seat, err)
+		if h.pub != nil {
+			h.pub.unread(ctx, se.seat, m.Subject(), err)
+		}
+		h.ack(m)
+		return true
+	}
+	if h.pub != nil {
+		h.pub.read(ctx, se.seat)
+	}
+	id := ""
+	if m.Headers() != nil {
+		id = m.Headers().Get("x-event-id")
+	}
+	wake, err := h.n.Heard(ctx, se.seat, se.event, id, o)
+	if err != nil {
+		h.logf("%v; heard again", err)
+		if nakErr := m.Nak(); nakErr != nil {
+			h.logf("leaving %s for the bus to give again: %v", m.Subject(), nakErr)
+		}
+		return true
+	}
+	if h.pub != nil {
+		h.pub.heard(ctx, se.seat, se.event, o)
+	}
+	h.ack(m)
+	if len(wake) > 0 {
+		h.logf("the floor of %s is asked again: %s said %s", strings.Join(wake, ", "), se.seat, se.event)
+		h.b.Reconsider(ctx)
+	}
+	return true
+}
+
+func (h *seatHearer) ack(m jetstream.Msg) {
+	if err := m.Ack(); err != nil {
+		h.logf("acknowledging %s: %v", m.Subject(), err)
+	}
+}
+
+// kvKeeper is the state floor-waits as versions.FloorKeeper.
+type kvKeeper struct {
+	ctx context.Context
+	kv  jetstream.KeyValue
+}
+
+func (k kvKeeper) Put(key string, value []byte) error {
+	_, err := k.kv.Put(k.ctx, key, value)
+	return err
+}
+
+func (k kvKeeper) Delete(key string) error {
+	err := k.kv.Delete(k.ctx, key)
+	if errors.Is(err, jetstream.ErrKeyNotFound) {
+		return nil
+	}
+	return err
+}
+
+// heldFloorWaits are the waits floor-waits holds at the builder's start; a value that is no wait is said and left.
+func heldFloorWaits(ctx context.Context, kv jetstream.KeyValue, logf func(string, ...any)) []versions.FloorWait {
+	l, err := kv.ListKeys(ctx)
+	if err != nil {
+		logf("%s cannot be listed, so a restart's waits are asked at their next claim: %v", versions.FloorWaitsState, err)
+		return nil
+	}
+	defer func() { _ = l.Stop() }()
+	var out []versions.FloorWait
+	for k := range l.Keys() {
+		e, err := kv.Get(ctx, k)
+		if err != nil {
+			continue
+		}
+		w, err := versions.DecodeFloorWait(e.Value())
+		if err != nil {
+			logf("%s.%s holds what is no floor wait, left: %v", versions.FloorWaitsState, k, err)
+			continue
+		}
+		out = append(out, w)
+	}
+	return out
+}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/standing.go

@@ -1,211 +0,0 @@
-package main
-
-// This file is the same in mesh-delivery-indexer, mesh-delivery-builder and mesh-delivery-checker (issue 1940): it moves
-// to mesh-sdk go/delivery/buildrun once mesh-sdk can be delivered again, since a change of mesh-sdk waits on the very
-// toolchain agreement this file repairs.
-
-import (
-	"context"
-	"encoding/json"
-	"fmt"
-	"log"
-	"maps"
-	"slices"
-	"strings"
-	"sync"
-	"time"
-
-	"github.com/nats-io/nats.go/jetstream"
-
-	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/provider"
-)
-
-// A build module writes <node>.<language> of its toolchains state on every node it runs on, and nothing deletes the key
-// when the module is unassigned from a node: the controller writes no module's state, and the module is gone. A report of
-// a node the build module no longer runs on is therefore not a builder (issue 1940: mesh-build-node unassigned from ace
-// on 2026-10-23 left ace.typescript at v26.12.0, and every Node fingerprint said "builders disagree").
-//
-// toolchainGate stands between the toolchains buckets and what takes their entries in (the indexer's PutToolchain, a
-// buildrun.ToolchainSet): an entry is passed on only while the controller's assignments (mesh-controller_assignments,
-// key <node>.<module>) hold an open assignment of its build module on its node, and only once it was written since that
-// assignment; it is passed on as deleted otherwise, said once, and passed on when its node writes it again. A report
-// written before the assignment is the one an earlier run of the module left (issue 1940, 2026-10-25 20:56: mesh-build-node
-// assigned to ace again brought ace.typescript v26.12.0 of 2026-10-23 back into the agreement, before the module ran
-// there, and the controller's take-in refused every module "builders disagree"). Until the assignments are settled (or where they cannot
-// be read) every entry is passed on, as before. Builders that run and report different versions still disagree: that
-// refusal is the guard of novox/hq ADR 0465, and it stays.
-type toolchainGate struct {
-	mu       sync.Mutex
-	modules  map[string]bool                                           // the build modules whose toolchains pass the gate
-	forward  func(module, key string, value []byte, deleted bool) bool // answers whether it changed what it holds
-	logf     func(format string, a ...any)
-	known    bool                         // the assignments are settled
-	standing map[string]time.Time         // <node>.<module> with an open assignment -> since when it stands
-	raw      map[string]map[string][]byte // module -> toolchains key -> value, as the bucket holds it
-	left     map[string]string            // <module>/<key> -> why it was said left out, so each reason is said once
-}
-
-func newToolchainGate(modules []string, forward func(module, key string, value []byte, deleted bool) bool, logf func(string, ...any)) *toolchainGate {
-	g := &toolchainGate{modules: map[string]bool{}, forward: forward, logf: logf, standing: map[string]time.Time{},
-		raw: map[string]map[string][]byte{}, left: map[string]string{}}
-	for _, m := range modules {
-		g.modules[m] = true
-	}
-	return g
-}
-
-// Toolchain takes one change of a build module's toolchains bucket in and answers whether what it passed on changed.
-func (g *toolchainGate) Toolchain(module, key string, value []byte, deleted bool) bool {
-	g.mu.Lock()
-	defer g.mu.Unlock()
-	if g.raw[module] == nil {
-		g.raw[module] = map[string][]byte{}
-	}
-	if deleted {
-		delete(g.raw[module], key)
-	} else {
-		g.raw[module][key] = value
-	}
-	return g.pass(module, key)
-}
-
-// Assignment takes one change of the controller's assignments in (at is when the bus wrote that revision) and answers
-// whether what it passed on changed.
-func (g *toolchainGate) Assignment(key string, value []byte, deleted bool, at time.Time) bool {
-	node, module, ok := strings.Cut(key, ".")
-	if !ok || !g.modules[module] {
-		return false
-	}
-	assigned, open := openAssignment(value)
-	open = open && !deleted
-	g.mu.Lock()
-	defer g.mu.Unlock()
-	was, stood := g.standing[key]
-	since := assigned
-	if since.IsZero() {
-		// A value with no time of its own (an assignment a module pulled in) stands since the revision that opened it.
-		since = at
-		if stood {
-			since = was
-		}
-	}
-	if open == stood && (!open || since.Equal(was)) {
-		return false
-	}
-	if open {
-		g.standing[key] = since
-	} else {
-		delete(g.standing, key)
-	}
-	if !g.known {
-		return false
-	}
-	changed := false
-	for _, k := range slices.Sorted(maps.Keys(g.raw[module])) {
-		if n, _, err := delivery.ParseToolchainKey(k); err == nil && n == node {
-			changed = g.pass(module, k) || changed
-		}
-	}
-	return changed
-}
-
-// Settled says the assignments are read: from now on only the reports of assigned nodes pass. It answers whether what it
-// passed on changed.
-func (g *toolchainGate) Settled() bool {
-	g.mu.Lock()
-	defer g.mu.Unlock()
-	g.known = true
-	changed := false
-	for _, module := range slices.Sorted(maps.Keys(g.raw)) {
-		for _, k := range slices.Sorted(maps.Keys(g.raw[module])) {
-			changed = g.pass(module, k) || changed
-		}
-	}
-	return changed
-}
-
-// pass hands one key on as it stands: its value when its node is assigned and wrote it since (or the assignments are not
-// known), deleted otherwise. The caller holds mu.
-func (g *toolchainGate) pass(module, key string) bool {
-	value, held := g.raw[module][key]
-	if !held {
-		return g.forward(module, key, nil, true)
-	}
-	node, _, err := delivery.ParseToolchainKey(key)
-	why := ""
-	if err == nil && g.known {
-		why = g.leftOut(module, node, value)
-	}
-	if why == "" {
-		delete(g.left, module+"/"+key)
-		return g.forward(module, key, value, false)
-	}
-	if g.left[module+"/"+key] != why {
-		g.left[module+"/"+key] = why
-		g.logf("%s.%s is left out of the agreed toolchain: %s (issue 1940)", delivery.ToolchainsBucket(module), key, why)
-	}
-	return g.forward(module, key, nil, true)
-}
-
-// leftOut is why a node's report is no builder's, or empty when it counts: its node has no open assignment of the module,
-// or the report was written before that assignment. A value that is no toolchain is passed on for its reader to refuse.
-// The caller holds mu.
-func (g *toolchainGate) leftOut(module, node string, value []byte) string {
-	since, open := g.standing[node+"."+module]
-	if !open {
-		return fmt.Sprintf("%s has no assignment on %s, so it is no builder", module, node)
-	}
-	tc, err := delivery.DecodeToolchain(value)
-	if err == nil && tc.At.Before(since) {
-		return fmt.Sprintf("it was written at %s, before %s's assignment on %s at %s: it counts once %s writes it again",
-			tc.At.UTC().Format(time.RFC3339), module, node, since.UTC().Format(time.RFC3339), node)
-	}
-	return ""
-}
-
-// openAssignment is whether a value of the controller's assignments holds an assignment that stands (one that has not
-// ended and has no state: a pending one is not on the machine yet; mesh-controller internal/chain Assignment), and when
-// it was assigned, zero where the value does not say.
-func openAssignment(value []byte) (time.Time, bool) {
-	var a struct {
-		Assigned time.Time `json:"assigned"`
-		Ended    time.Time `json:"ended"`
-		State    string    `json:"state"`
-	}
-	if json.Unmarshal(value, &a) != nil {
-		return time.Time{}, false
-	}
-	return a.Assigned, a.Ended.IsZero() && a.State == ""
-}
-
-// watchAssignments settles the controller's assignments into the gate, says them settled, and follows them; changed is
-// told whenever what the gate passes on changed. Where the bucket cannot be read (not there, or this module may not read
-// it) it says so and the gate passes every report on, as before; an error of the watch after that ends on the channel.
-func watchAssignments(ctx context.Context, js bucketOpener, gate *toolchainGate, changed func(context.Context), logger *log.Logger) (<-chan error, error) {
-	errs := make(chan error, 1)
-	kv, err := js.KeyValue(ctx, provider.AssignmentsBucket)
-	if err != nil {
-		// Not fatal: an indexer, builder or checker that stops for it stops every delivery (a grant comes with a delivery).
-		logger.Printf("the bucket %s cannot be read, so every node's toolchain report counts, an unassigned build node's too (issue 1940): %v", provider.AssignmentsBucket, err)
-		return errs, nil
-	}
-	each := func(e jetstream.KeyValueEntry) { gate.Assignment(e.Key(), e.Value(), !opOf(e), e.Created()) }
-	w, err := settle(ctx, kv, each)
-	if err != nil {
-		// Not fatal either (issue 1945): a watch the bus refuses is the same missing grant as a refused read.
-		logger.Printf("the bucket %s cannot be watched, so every node's toolchain report counts, an unassigned build node's too (issue 1940): %v", provider.AssignmentsBucket, err)
-		return errs, nil
-	}
-	if gate.Settled() {
-		changed(ctx)
-	}
-	go func() {
-		errs <- follow(ctx, w, func(e jetstream.KeyValueEntry) {
-			if gate.Assignment(e.Key(), e.Value(), !opOf(e), e.Created()) {
-				changed(ctx)
-			}
-		})
-	}()
-	return errs, nil
-}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/standing_test.go

@@ -1,228 +0,0 @@
-package main
-
-// The same in mesh-delivery-indexer, mesh-delivery-builder and mesh-delivery-checker, as standing.go is (issue 1940).
-
-import (
-	"bytes"
-	"context"
-	"errors"
-	"fmt"
-	"log"
-	"strings"
-	"testing"
-	"time"
-
-	"git.novox.be/novox/mesh-sdk/go/process"
-
-	"github.com/nats-io/nats.go/jetstream"
-
-	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
-)
-
-func gateReport(t *testing.T, node, version string) (string, []byte) {
-	t.Helper()
-	key, err := delivery.ToolchainKey(node, "typescript")
-	if err != nil {
-		t.Fatal(err)
-	}
-	value, err := delivery.EncodeToolchain(delivery.Toolchain{Language: "typescript", Version: version, Recipe: "f59571cf4be75adf", At: time.Unix(0, 0).UTC()})
-	if err != nil {
-		t.Fatal(err)
-	}
-	return key, value
-}
-
-func agreedOf(set *buildrun.ToolchainSet) (string, string) {
-	tc, none := delivery.AgreedToolchain(set.Entries("typescript"))
-	return tc.Version, none
-}
-
-// The live case of issue 1940: mesh-build-node was unassigned from ace, whose report stayed at v26.12.0 while the
-// three nodes it runs on report v26.12.1. Without the assignments every report counts (and they disagree); with them
-// ace's is left out and the three agree; assigned to ace again, its report counts again and the guard refuses again.
-func TestAnUnassignedBuildNodesReportIsNoBuilder(t *testing.T) {
-	set := &buildrun.ToolchainSet{}
-	var said []string
-	gate := newToolchainGate([]string{buildrun.GoBuildModule, buildrun.NodeBuildModule}, set.Put, func(f string, a ...any) { said = append(said, f) })
-	for node, version := range map[string]string{"ace": "v26.12.0", "g14": "v26.12.1", "novox": "v26.12.1", "shanks": "v26.12.1"} {
-		key, value := gateReport(t, node, version)
-		gate.Toolchain(buildrun.NodeBuildModule, key, value, false)
-	}
-	if _, none := agreedOf(set); !strings.HasPrefix(none, "builders disagree") {
-		t.Fatalf("before the assignments are read every report counts, so they disagree; got %q", none)
-	}
-	for _, node := range []string{"g14", "novox", "shanks"} {
-		gate.Assignment(node+"."+buildrun.NodeBuildModule, []byte(`{"node":"`+node+`","module":"mesh-build-node"}`), false, time.Time{})
-	}
-	gate.Assignment("ace.mesh-build-node", []byte(`{"node":"ace","module":"mesh-build-node","ended":"2026-10-23T08:00:00Z"}`), false, time.Time{})
-	gate.Assignment("ace.mesh-build-go", []byte(`{"node":"ace","module":"mesh-build-go"}`), false, time.Time{}) // another module's: no matter
-	if !gate.Settled() {
-		t.Fatal("settling the assignments left ace's report out, so what was passed on changed")
-	}
-	if v, none := agreedOf(set); v != "v26.12.1" || none != "" {
-		t.Fatalf("the assigned nodes agree on v26.12.1; got %q, %q", v, none)
-	}
-	if len(said) != 1 {
-		t.Fatalf("ace's report is said left out once; said %v", said)
-	}
-	// ace reports again while unassigned (an old value seen again): still left out.
-	key, value := gateReport(t, "ace", "v26.12.0")
-	if gate.Toolchain(buildrun.NodeBuildModule, key, value, false) {
-		t.Fatal("an unassigned node's report changed what was passed on")
-	}
-	// Assigned to ace again: its report counts, and the builders really disagree: the guard stays.
-	if !gate.Assignment("ace.mesh-build-node", []byte(`{"node":"ace","module":"mesh-build-node"}`), false, time.Time{}) {
-		t.Fatal("assigning ace again passed nothing on")
-	}
-	if _, none := agreedOf(set); !strings.HasPrefix(none, "builders disagree: v26.12.0 recipe f59571cf4be75adf on ace") {
-		t.Fatalf("builders that run different versions still disagree; got %q", none)
-	}
-	// The assignment's key deleted, or a pending one written: no assignment stands, and ace's report goes again.
-	if !gate.Assignment("ace.mesh-build-node", []byte(`{"node":"ace","module":"mesh-build-node","state":"pending"}`), false, time.Time{}) {
-		t.Fatal("a pending assignment is no assignment on the machine")
-	}
-	if v, none := agreedOf(set); v != "v26.12.1" || none != "" {
-		t.Fatalf("got %q, %q", v, none)
-	}
-	gate.Assignment("ace.mesh-build-node", nil, true, time.Time{})
-	if v, _ := agreedOf(set); v != "v26.12.1" {
-		t.Fatalf("got %q", v)
-	}
-	// A report deleted from the bucket goes whether its node is assigned or not.
-	key, _ = gateReport(t, "g14", "v26.12.1")
-	if !gate.Toolchain(buildrun.NodeBuildModule, key, nil, true) {
-		t.Fatal("deleting g14's report passed nothing on")
-	}
-	if n := len(set.Entries("typescript")); n != 2 {
-		t.Fatalf("novox and shanks are left; got %d entries", n)
-	}
-
-	// 1945 (a part exits at start for a bucket it works without): a bus that refuses the assignments' watch, or every
-	// toolchains bucket, leaves the watches unstarted and the part running, said; a refused bucket it cannot work without
-	// is an error naming the bucket and its grant.
-	var logs bytes.Buffer
-	logger := log.New(&logs, "", 0)
-	refused := refusingBus{err: errors.New("nats: permissions violation for publish to $JS.API.CONSUMER.CREATE.KV_mesh-controller_assignments")}
-	if _, err := watchAssignments(context.Background(), refused, newToolchainGate(nil, set.Put, t.Logf), func(context.Context) {}, logger); err != nil {
-		t.Errorf("a refused watch of the assignments stopped the start: %v", err)
-	}
-	if err := newToolchainWatch(context.Background(), refusingBus{refuseOpen: true, err: refused.err}, set, func(context.Context) {}, logger).start(); err != nil {
-		t.Errorf("a refused toolchains bucket stopped the start: %v", err)
-	}
-	if !strings.Contains(logs.String(), "cannot be watched") || !strings.Contains(logs.String(), "cannot be read") {
-		t.Errorf("the refusals were not said: %q", logs.String())
-	}
-	if _, err := process.EssentialBucket(context.Background(), refusingBus{refuseOpen: true, err: refused.err}, "builder", "mesh-delivery-indexer_modules", "work"); err == nil ||
-		!strings.Contains(err.Error(), "grant of mesh-delivery-indexer_modules") {
-		t.Errorf("a refused bucket the part needs: %v, want an error naming its grant", err)
-	}
-	// The gate's source (the previews' trunk heads): refused at start, the builder goes on, and a candidate asking a trunk
-	// head is told why and opens it again then.
-	src := &trunkSource{ctx: context.Background(), js: refusingBus{refuseOpen: true, err: refused.err}, heads: &sourceHeads{}, errs: make(chan error, 1), logf: logger.Printf}
-	src.start()
-	if _, err := src.head(context.Background(), 7, "novox/mesh-catalog"); err == nil || !strings.Contains(err.Error(), delivery.SourceBucket) {
-		t.Errorf("a trunk head with the source refused: %v, want why", err)
-	}
-	if src.opened {
-		t.Error("a refused source counts as opened, so it is never opened again")
-	}
-}
-
-// refusingBus is a bus that refuses: every open (refuseOpen), or every watch of a bucket it opens, with err.
-type refusingBus struct {
-	refuseOpen bool
-	err        error
-}
-
-func (r refusingBus) KeyValue(context.Context, string) (jetstream.KeyValue, error) {
-	if r.refuseOpen {
-		return nil, r.err
-	}
-	return refusedWatch{err: r.err}, nil
-}
-
-type refusedWatch struct {
-	jetstream.KeyValue
-	err error
-}
-
-func (r refusedWatch) WatchAll(context.Context, ...jetstream.WatchOpt) (jetstream.KeyWatcher, error) {
-	return nil, r.err
-}
-func (r refusedWatch) Watch(context.Context, string, ...jetstream.WatchOpt) (jetstream.KeyWatcher, error) {
-	return nil, r.err
-}
-
-// A build node's report counts from the first one it writes since its assignment: a newly assigned node that has not
-// reported changes nothing, and the report an earlier run left on the bus (issue 1940, 2026-10-25 20:56: ace.typescript
-// v26.12.0 of 2026-10-23 06:29, mesh-build-node assigned to ace again at 20:56:45) is left out, said once, until the node
-// writes it again. An assignment whose value names no time stands since the revision that opened it.
-func TestANewlyAssignedNodeCountsFromItsReport(t *testing.T) {
-	left := time.Date(2026, 10, 23, 6, 29, 18, 0, time.UTC)      // ace's report from its earlier run
-	assigned := time.Date(2026, 10, 25, 19, 56, 45, 0, time.UTC) // mesh-build-node assigned to ace again
-	report := func(t *testing.T, node, version string, at time.Time) (string, []byte) {
-		key, _ := gateReport(t, node, version)
-		value, err := delivery.EncodeToolchain(delivery.Toolchain{Language: "typescript", Version: version, Recipe: "f59571cf4be75adf", At: at})
-		if err != nil {
-			t.Fatal(err)
-		}
-		return key, value
-	}
-	for _, c := range []struct {
-		name       string
-		assignment string    // ace's assignment value
-		revision   time.Time // when the bus wrote it
-		at         time.Time // when ace wrote its report
-		counts     bool
-	}{
-		{"no report yet, then one", `{}`, time.Time{}, time.Now(), true},
-		{"a report left before the assignment", `{"node":"ace","module":"mesh-build-node","assigned":"2026-10-25T19:56:45Z"}`, assigned, left, false},
-		{"a report left before a value with no time", `{"node":"ace","module":"mesh-build-node"}`, assigned, left, false},
-		{"a report written since the assignment", `{"node":"ace","module":"mesh-build-node","assigned":"2026-10-25T19:56:45Z"}`, assigned, assigned.Add(30 * time.Second), true},
-	} {
-		t.Run(c.name, func(t *testing.T) {
-			set := &buildrun.ToolchainSet{}
-			var said []string
-			gate := newToolchainGate([]string{buildrun.NodeBuildModule}, set.Put, func(f string, a ...any) { said = append(said, fmt.Sprintf(f, a...)) })
-			for _, node := range []string{"g14", "novox", "shanks"} {
-				gate.Assignment(node+".mesh-build-node", []byte(`{}`), false, time.Time{})
-				key, value := gateReport(t, node, "v26.12.1")
-				gate.Toolchain(buildrun.NodeBuildModule, key, value, false)
-			}
-			gate.Settled()
-			if gate.Assignment("ace.mesh-build-node", []byte(c.assignment), false, c.revision) {
-				t.Fatal("an assignment with no report passed something on")
-			}
-			key, value := report(t, "ace", "v26.12.0", c.at)
-			if got := gate.Toolchain(buildrun.NodeBuildModule, key, value, false); got != c.counts {
-				t.Fatalf("ace's report passed on: %v, want %v", got, c.counts)
-			}
-			// A rewrite of the assignment that does not move it changes nothing, and nothing is said again.
-			if gate.Assignment("ace.mesh-build-node", []byte(c.assignment), false, c.revision.Add(time.Minute)) {
-				t.Fatal("the same assignment written again changed what was passed on")
-			}
-			v, none := agreedOf(set)
-			if c.counts {
-				if !strings.HasPrefix(none, "builders disagree: v26.12.0 recipe f59571cf4be75adf on ace") {
-					t.Fatalf("ace's own report counts and disagrees; got %q, %q", v, none)
-				}
-				return
-			}
-			if v != "v26.12.1" || none != "" {
-				t.Fatalf("ace's left report is no builder's, so g14, novox and shanks agree; got %q, %q", v, none)
-			}
-			if len(said) != 1 || !strings.Contains(said[0], "before mesh-build-node's assignment on ace at 2026-10-25T19:56:45Z") {
-				t.Fatalf("said %q, want once why ace's report is left out", said)
-			}
-			// ace writes its report again since it was assigned: it counts.
-			key, value = report(t, "ace", "v26.12.1", assigned.Add(time.Minute))
-			if !gate.Toolchain(buildrun.NodeBuildModule, key, value, false) {
-				t.Fatal("ace's new report was not passed on")
-			}
-			if n := len(set.Entries("typescript")); n != 4 {
-				t.Fatalf("four builders report; got %d", n)
-			}
-		})
-	}
-}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/stored.go

@@ -9,26 +9,31 @@ import (
 
 	"github.com/nats-io/nats.go/jetstream"
 
+	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
 
 	"mesh-delivery-builder/internal/build"
 )
 
-// eventsStream is the stream every module's and role's events are on, where the controller makes the builder's durable
-// consumer of artifacts-gone (mesh-controller internal/broker EventsStream).
+// eventsStream is the stream every module's and role's events are on, where the grants part makes the builder's durable
+// consumer of artifacts-gone (mesh-sdk buscompose EventsStream).
 const eventsStream = "EVENTS"
 
+// SeatHeld is the seat mesh-artifact-sweep's verb held (ADR 0571 §2).
+const SeatHeld = "seat:" + catalogue.ArtifactSweepSeat + ".held"
+
 // toolCaller calls a tool or a seat verb as the builder's own account (mesh-sdk process.Conn.Call).
 type toolCaller func(key string, body any) (json.RawMessage, error)
 
-// storedVia is build.Builder's Stored: it asks the controller's verb held (mesh-sdk delivery.HeldVerb; novox/hq issue
-// 1937) and answers the references the store no longer holds. One it could not ask about, with none gone, is an error:
-// the key is then left done, and the controller's take-in still refuses a gone blob.
+// storedVia is build.Builder's Stored: it asks the seat mesh-artifact-sweep's `held` (novox/hq ADR 0571 §2, issue 1937)
+// and answers the references the store no longer holds. One it could not ask about, with none gone, is an error: the key
+// is then left done, and asked again at the next module value or artifacts-gone.
 func storedVia(call toolCaller) func(ctx context.Context, references []string) ([]string, error) {
 	return func(_ context.Context, references []string) ([]string, error) {
-		raw, err := call(delivery.HeldVerb, map[string]any{"references": references})
+		body := map[string]any{"references": references}
+		raw, err := call(SeatHeld, body)
 		if err != nil {
-			return nil, fmt.Errorf("asking %s: %w", delivery.HeldVerb, err)
+			return nil, fmt.Errorf("asking held: %w", err)
 		}
 		a, err := delivery.DecodeHeldAnswer(raw, references)
 		if err != nil {

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/tagbounds.go

@@ -0,0 +1,132 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"time"
+
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+
+	"mesh-delivery-builder/internal/versions"
+)
+
+// tagBounds narrates a tag ask the builder has not answered within five minutes, with what it waits on (design 51
+// *Tagged versions*): each unanswered ask has a key in the state tag-ask-bounds written with its own time to live, and
+// the bus's marker of its end, heard on the watch, is what narrates it and writes the bound again. No timer.
+type tagBounds struct {
+	asks   func() jetstream.KeyValue
+	bounds func() jetstream.KeyValue
+	waits  func() []versions.FloorWait
+	logf   func(string, ...any)
+	// log writes a narration into the builder's build log (build.said); nil writes none.
+	log   func(delivery.BuildLogEntry)
+	now   func() time.Time
+	bound time.Duration
+}
+
+// arm writes key's bound when none stands: a Create, so a standing bound keeps its time and a restart arms each
+// unanswered ask whose bound ended while the builder was away.
+func (tb *tagBounds) arm(ctx context.Context, key string) {
+	kv := tb.bounds()
+	if kv == nil {
+		return
+	}
+	if _, err := kv.Create(ctx, key, []byte(`{}`), jetstream.KeyTTL(tb.bound)); err != nil && !errors.Is(err, jetstream.ErrKeyExists) {
+		tb.logf("the bound of the tag ask %s is not written, so it is not narrated past five minutes: %v", key, err)
+	}
+}
+
+// disarm removes key's bound: the ask was answered or ended.
+func (tb *tagBounds) disarm(ctx context.Context, key string) {
+	if kv := tb.bounds(); kv != nil {
+		_ = kv.Delete(ctx, key)
+	}
+}
+
+// asked is told each value of tag-asks: an unanswered ask is armed, any other disarmed.
+func (tb *tagBounds) asked(ctx context.Context, key string, t versions.TagAsk) {
+	if t.Unanswered() {
+		tb.arm(ctx, key)
+		return
+	}
+	tb.disarm(ctx, key)
+}
+
+// ended is told each change of tag-ask-bounds: a bound whose time ended (the bus's marker, a purge on the watch) on an
+// ask still unanswered narrates it and arms it again.
+func (tb *tagBounds) ended(ctx context.Context, e jetstream.KeyValueEntry) {
+	if e.Operation() != jetstream.KeyValuePurge {
+		return
+	}
+	kv := tb.asks()
+	if kv == nil {
+		return
+	}
+	got, err := kv.Get(ctx, e.Key())
+	if err != nil {
+		return // the ask ended with its branch
+	}
+	t, err := versions.DecodeTagAsk(got.Value())
+	if err != nil || !t.Unanswered() {
+		return
+	}
+	var waits []versions.FloorWait
+	if tb.waits != nil {
+		waits = tb.waits()
+	}
+	line := versions.NarrateUnanswered(t, waits, tb.now())
+	tb.logf("%s", line)
+	// In the build log too (design 51 *Tagged versions*): under the builder's own key, no build being claimed yet, the
+	// ask's key standing for the fingerprint.
+	if tb.log != nil {
+		tb.log(delivery.BuildLogEntry{Event: delivery.BuildSaidEvent, Module: delivery.BuilderModule, FP: e.Key(), Commit: t.Head,
+			At: tb.now().UTC(), Line: line, Why: versions.SaidUnanswered})
+	}
+	tb.arm(ctx, e.Key())
+}
+
+// tagNumbered marks the tag ask of a check's build's head numbered with its versions in tag-asks, by compare-and-set.
+func tagNumbered(kv func() jetstream.KeyValue, logf func(string, ...any), now func() time.Time) func(context.Context, versions.BuildClaim, versions.Numbering) {
+	return func(ctx context.Context, c versions.BuildClaim, got versions.Numbering) {
+		store := kv()
+		if store == nil {
+			return
+		}
+		lister, err := store.ListKeysFiltered(ctx, versions.EscapeToken(c.Repository)+".>")
+		if err != nil {
+			logf("the tag ask of %s at %s is not marked numbered: %v", c.Repository, c.Head, err)
+			return
+		}
+		for key := range lister.Keys() {
+			for range 3 {
+				e, err := store.Get(ctx, key)
+				if err != nil {
+					break
+				}
+				t, err := versions.DecodeTagAsk(e.Value())
+				if err != nil {
+					break
+				}
+				t, changed := t.WithNumbered(c.Module, c.Head, got.Versions, got.Names, now())
+				if !changed {
+					break
+				}
+				data, err := json.Marshal(t)
+				if err != nil {
+					break
+				}
+				if _, err = store.Update(ctx, key, data, e.Revision()); err == nil {
+					logf("%s: tag ask of %s %s: %s", key, t.Repository, t.Branch, t.Answer)
+					break
+				}
+				if !errors.Is(err, jetstream.ErrKeyExists) && !errors.Is(err, jetstream.ErrKeyRevisionMismatch) {
+					logf("the tag ask %s is not marked numbered: %v", key, err)
+					break
+				}
+			}
+		}
+	}
+}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/toolchains.go

@@ -8,7 +8,7 @@ import (
 	"strings"
 	"sync"
 
-	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
+	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun"
 	"git.novox.be/novox/mesh-sdk/go/process"
 
 	"github.com/nats-io/nats.go/jetstream"

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/versions.go

@@ -0,0 +1,352 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/nats-io/nats.go"
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-contracts/go/seats/ociartifactregistry"
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+	"git.novox.be/novox/mesh-sdk/go/health"
+	"git.novox.be/novox/mesh-sdk/go/process"
+
+	"mesh-delivery-builder/internal/build"
+	"mesh-delivery-builder/internal/versions"
+)
+
+// The floor's two module tools (novox/hq design 51 *The floor*); the seat's is `seat:<registry>.versions`.
+const (
+	bridgeTagsTool   = "mesh-delivery-forge-bridge.bridge_tags"
+	requirementsTool = "mesh-delivery-indexer.indexer_requirements"
+)
+
+// awaitedVersions is the state versions as versions.Store: bound once the bus holds it (the grants part makes it, issue
+// 1790); until then every use is an error, so a trunk build is built unnumbered and said (build.Builder.number).
+type awaitedVersions struct{ b *process.AwaitedBucket }
+
+var errVersionsMissing = errors.New("the state " + versions.Bucket + " is not on the bus yet")
+
+func (s awaitedVersions) kv() (jetstream.KeyValue, error) {
+	if kv := s.b.KV(); kv != nil {
+		return kv, nil
+	}
+	return nil, errVersionsMissing
+}
+
+func (s awaitedVersions) Get(ctx context.Context, key string) ([]byte, uint64, bool, error) {
+	kv, err := s.kv()
+	if err != nil {
+		return nil, 0, false, err
+	}
+	e, err := kv.Get(ctx, key)
+	if errors.Is(err, jetstream.ErrKeyNotFound) {
+		return nil, 0, false, nil
+	}
+	if err != nil {
+		return nil, 0, false, err
+	}
+	return e.Value(), e.Revision(), true, nil
+}
+
+// indexerPackages is the indexer's packages state as the builder reads a package's name in its ecosystem from it (design
+// 32): the picture of its read tool's first view and its views family (ADR 0615 §1), never its bucket. Until the first
+// view is answered a package is built unnumbered and said (versions.Numberer.Names), and numbered once its name is heard
+// (followPackages).
+type indexerPackages struct{ kv jetstream.KeyValue }
+
+func (s indexerPackages) Keys(ctx context.Context) ([]string, error) {
+	keys, err := s.kv.Keys(ctx)
+	if errors.Is(err, jetstream.ErrNoKeysFound) {
+		return nil, nil
+	}
+	return keys, err
+}
+
+func (s indexerPackages) Get(ctx context.Context, key string) ([]byte, bool, error) {
+	e, err := s.kv.Get(ctx, key)
+	if errors.Is(err, jetstream.ErrKeyNotFound) || errors.Is(err, jetstream.ErrKeyDeleted) {
+		return nil, false, nil
+	}
+	if err != nil {
+		return nil, false, err
+	}
+	return e.Value(), true, nil
+}
+
+// followPackages watches the picture of the indexer's packages state: each series key heard that names a package's name
+// (versions.NamedModule), its first view's included, looks at its module again (build.Builder.PackageNamed), so a done
+// build that left the package unnumbered is numbered then with its digests. Woken by the views family, never a timer; a
+// key heard again naming the name and module it named (the indexer writes a series at each publish) looks at nothing.
+func followPackages(ctx context.Context, kv jetstream.KeyValue, b *build.Builder, logf func(string, ...any)) error {
+	w, err := kv.WatchAll(ctx)
+	if err != nil {
+		return err
+	}
+	heard := map[string]string{}
+	return follow(ctx, w, func(e jetstream.KeyValueEntry) {
+		if e.Operation() != jetstream.KeyValuePut {
+			delete(heard, e.Key())
+			return
+		}
+		module, name, named := versions.NamedModule(e.Key(), e.Value())
+		if named && heard[e.Key()] != module+" "+name {
+			heard[e.Key()] = module + " " + name
+			logf("%s.%s names a package of %s: its build is looked at again", delivery.PackagesBucket, e.Key(), module)
+			b.PackageNamed(ctx, module)
+		}
+	})
+}
+
+func versionsConflict(err error) error {
+	if errors.Is(err, jetstream.ErrKeyExists) || errors.Is(err, jetstream.ErrKeyRevisionMismatch) {
+		return versions.ErrConflict
+	}
+	return err
+}
+
+func (s awaitedVersions) Create(ctx context.Context, key string, value []byte) (uint64, error) {
+	kv, err := s.kv()
+	if err != nil {
+		return 0, err
+	}
+	rev, err := kv.Create(ctx, key, value)
+	return rev, versionsConflict(err)
+}
+
+func (s awaitedVersions) Update(ctx context.Context, key string, value []byte, revision uint64) (uint64, error) {
+	kv, err := s.kv()
+	if err != nil {
+		return 0, err
+	}
+	rev, err := kv.Update(ctx, key, value, revision)
+	return rev, versionsConflict(err)
+}
+
+func (s awaitedVersions) KeysOf(ctx context.Context, filter string) ([]string, error) {
+	kv, err := s.kv()
+	if err != nil {
+		return nil, err
+	}
+	l, err := kv.ListKeysFiltered(ctx, filter)
+	if err != nil {
+		return nil, err
+	}
+	defer func() { _ = l.Stop() }()
+	var out []string
+	for k := range l.Keys() {
+		out = append(out, k)
+	}
+	return out, nil
+}
+
+// floorVia is the floor's three sources as calls of the builder's own account (design 51 *The floor*): the seat's verb
+// versions, the forge bridge's bridge_tags and the indexer's indexer_requirements. A call that fails is that source
+// silent.
+func floorVia(call toolCaller) versions.FloorSources {
+	return versions.FloorSources{
+		Seat: func(_ context.Context, seat, name string) ([]string, error) {
+			raw, err := call("seat:"+seat+".versions", map[string]any{"name": name})
+			if err != nil {
+				return nil, err
+			}
+			var a struct {
+				Versions []struct {
+					Version string `json:"version"`
+				} `json:"versions"`
+			}
+			if err := json.Unmarshal(raw, &a); err != nil {
+				return nil, fmt.Errorf("%s's versions answered what is no list of versions: %w", seat, err)
+			}
+			var out []string
+			for _, v := range a.Versions {
+				if v.Version != "" {
+					out = append(out, v.Version)
+				}
+			}
+			return out, nil
+		},
+		Tags: func(_ context.Context, repository, prefix string) ([]string, error) {
+			raw, err := call(bridgeTagsTool, map[string]any{"repository": repository, "prefix": prefix})
+			if err != nil {
+				return nil, err
+			}
+			var a struct {
+				Tags []string `json:"tags"`
+			}
+			if err := json.Unmarshal(raw, &a); err != nil {
+				return nil, fmt.Errorf("bridge_tags answered what is no list of tags: %w", err)
+			}
+			return a.Tags, nil
+		},
+		Requirements: func(_ context.Context, name string) ([]string, error) {
+			raw, err := call(requirementsTool, map[string]any{"package": name})
+			if err != nil {
+				return nil, err
+			}
+			var a struct {
+				Requirements []string `json:"requirements"`
+			}
+			if err := json.Unmarshal(raw, &a); err != nil {
+				return nil, fmt.Errorf("indexer_requirements answered what is no list of versions: %w", err)
+			}
+			return a.Requirements, nil
+		},
+	}
+}
+
+// emitNumbered says the builder's event version.numbered (design 51 *Events of the builder*), on its own family apart
+// from its builds' ends; the name and version are the bus's dedup id.
+func emitNumbered(ctx context.Context, js jetstream.JetStream, cred process.Account, b delivery.VersionNumbered) error {
+	id := "numbered-" + versions.Key(b.Name, b.Version)
+	if b.Again != "" {
+		id += "-again-" + b.Again
+	}
+	if err := emitEvent(ctx, js, cred, delivery.VersionNumberedEvent, id, b); err != nil {
+		return fmt.Errorf("saying %s for %s@%s: %w", delivery.VersionNumberedEvent, b.Name, b.Version, err)
+	}
+	return nil
+}
+
+// emitEvent says one of the builder's events, mesh.mod.<module>.event.<event>, with the SDK's envelope headers and id as
+// the bus's dedup id.
+func emitEvent(ctx context.Context, js jetstream.JetStream, cred process.Account, event, id string, body any) error {
+	data, err := json.Marshal(body)
+	if err != nil {
+		return err
+	}
+	msg := nats.NewMsg(cred.EventSubject(event))
+	msg.Header.Set("x-event-id", id)
+	msg.Header.Set("x-source", cred.Module)
+	msg.Header.Set("x-node", cred.Node)
+	msg.Header.Set("x-time", time.Now().UTC().Format(time.RFC3339Nano))
+	msg.Header.Set("content-type", "application/json")
+	msg.Data = data
+	pub, cancel := context.WithTimeout(ctx, 10*time.Second)
+	defer cancel()
+	_, err = js.PublishMsg(pub, msg, jetstream.WithMsgID(id))
+	return err
+}
+
+// The events on the builder's consumer of EVENTS that wake a floor (design 51 *The floor*, DLV-B3b).
+var (
+	manifestAcceptedSubject = "mesh.mod." + delivery.IndexerModule + ".event." + delivery.ManifestAcceptedEvent
+	conditionClearedSubject = "mesh.mod." + health.KeeperModule + ".event." + health.EventCleared
+)
+
+// floorWake asks the floor of the names an event wakes again, by looking at every module again: a trunk build is
+// numbered before its claim (build.Builder.number).
+type floorWake struct {
+	b     *build.Builder
+	waits *versions.FloorWaits
+	logf  func(string, ...any)
+}
+
+// heard takes a message of the consumer in when it is one that wakes a floor, acknowledged, and answers whether it was.
+func (f *floorWake) heard(ctx context.Context, m jetstream.Msg) bool {
+	switch m.Subject() {
+	case manifestAcceptedSubject:
+		f.ack(m)
+		f.wake(ctx, versions.WakeAccepted, "", "")
+	case conditionClearedSubject:
+		f.ack(m)
+		var e health.Event
+		if err := json.Unmarshal(m.Data(), &e); err != nil {
+			f.logf("%s holds what is no condition, left: %v", m.Subject(), err)
+			return true
+		}
+		for _, module := range conditionModules(e.Subject.ID) {
+			f.wake(ctx, versions.WakeCleared, "", module)
+		}
+	default:
+		return false
+	}
+	return true
+}
+
+func (f *floorWake) ack(m jetstream.Msg) {
+	if err := m.Ack(); err != nil {
+		f.logf("acknowledging %s: %v", m.Subject(), err)
+	}
+}
+
+// wake looks at every module again when the event wakes a name, and says which.
+func (f *floorWake) wake(ctx context.Context, kind, seat, module string) {
+	names := f.waits.Wake(kind, seat, module, "")
+	if len(names) == 0 {
+		return
+	}
+	f.logf("the floor of %s is asked again: %s", strings.Join(names, ", "), kind)
+	f.b.Reconsider(ctx)
+}
+
+// conditionModules are the tokens of a condition's subject id (`<node>/<module>`, `<module>.<check>`): a module named
+// among them is the one whose condition cleared.
+func conditionModules(id string) []string {
+	return strings.FieldsFunc(id, func(r rune) bool { return r == '/' || r == '.' || r == ':' })
+}
+
+// doneVia says whether a build key is done, read from the builder's own builds state: the build's file is held.
+func doneVia(b *build.Builder) func(ctx context.Context, module, fp string) (bool, error) {
+	return func(ctx context.Context, module, fp string) (bool, error) {
+		key, err := delivery.BuilderBuildKey(module, fp)
+		if err != nil {
+			return false, err
+		}
+		raw, _, found, err := b.Claimer.Store.Get(ctx, key)
+		if err != nil || !found {
+			return false, err
+		}
+		cur, err := delivery.DecodeBuilderBuild(raw)
+		if err != nil {
+			return false, err
+		}
+		return cur.State == delivery.BuildDone, nil
+	}
+}
+
+// removeVia calls a registry seat's remove for one tagged version, as the builder's own account (design 51 *Tagged
+// versions*): the reason tag-gone; the seat says removed on its events, or answers kept when another tag names the
+// digest (the registry part's RemoveAnswer: kept, reason, tags), which ends the remove.
+func removeVia(call toolCaller) func(ctx context.Context, seat string, e versions.Entry) (versions.RemoveOutcome, error) {
+	return func(_ context.Context, seat string, e versions.Entry) (versions.RemoveOutcome, error) {
+		raw, err := call("seat:"+seat+".remove", map[string]any{"name": e.Name, "version": e.Version, "tag": e.Tag, "reason": "tag-gone"})
+		if err != nil {
+			return versions.RemoveOutcome{}, err
+		}
+		var a ociartifactregistry.RemoveAnswer // the four registry seats share the part's answer
+		if len(raw) > 0 && json.Unmarshal(raw, &a) != nil {
+			return versions.RemoveOutcome{}, fmt.Errorf("%s's remove answered what is no answer of it: %s", seat, raw)
+		}
+		return versions.RemoveOutcome{Kept: a.Kept, Reason: a.Reason, Tags: a.Tags}, nil
+	}
+}
+
+// tagAsked answers an unanswered value of tag-asks by compare-and-set at its revision, said in the log.
+func tagAsked(ctx context.Context, acts versions.Acts, kv jetstream.KeyValue, e jetstream.KeyValueEntry, logf func(string, ...any)) {
+	if e.Operation() != jetstream.KeyValuePut {
+		return
+	}
+	t, err := versions.DecodeTagAsk(e.Value())
+	if err != nil {
+		logf("%s.%s holds what is not a tag ask, left: %v", versions.TagAsksState, e.Key(), err)
+		return
+	}
+	if !t.Answered.IsZero() {
+		return
+	}
+	t = acts.TagAsked(ctx, t, time.Now())
+	logf("%s: %s of %s %s by %s (%s): %s", e.Key(), map[bool]string{true: "untag", false: "tag ask"}[t.Untag], t.Repository, t.Branch, t.By, t.Why, t.Answer)
+	data, err := json.Marshal(t)
+	if err != nil {
+		return
+	}
+	if _, err := kv.Update(ctx, e.Key(), data, e.Revision()); err != nil && !errors.Is(err, jetstream.ErrKeyExists) && !errors.Is(err, jetstream.ErrKeyRevisionMismatch) {
+		logf("%s.%s: the answer could not be written: %v", versions.TagAsksState, e.Key(), err)
+	}
+}

modules/mesh-delivery-builder/go.mod

@@ -3,20 +3,44 @@ module mesh-delivery-builder
 go 1.26.0
 
 require (
-	git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028193502-f91340fe82ef
+	git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261104174359-05b3e2e1b94f
 	github.com/nats-io/nats-server/v2 v2.11.17
 	github.com/nats-io/nats.go v1.54.0
 )
 
+require git.novox.be/novox/mesh-catalog/modules/mesh-build-go/buildstep v0.0.0-20261104174638-125929dbc459
+
 require (
-	github.com/antithesishq/antithesis-sdk-go v0.7.0-default-no-op // indirect
+	git.novox.be/novox/mesh-contracts/go v0.0.0-20261104174344-ae5266e77639 // indirect
+	git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun v0.0.0-00010101000000-000000000000
+	github.com/antithesishq/antithesis-sdk-go v0.8.0-default-no-op // indirect
 	github.com/google/go-tpm v0.9.8 // indirect
-	github.com/klauspost/compress v1.20.0 // indirect
+	github.com/klauspost/compress v1.20.1 // indirect
 	github.com/minio/highwayhash v1.0.4 // indirect
-	github.com/nats-io/jwt/v2 v2.8.1 // indirect
+	github.com/nats-io/jwt/v2 v2.8.2 // indirect
 	github.com/nats-io/nkeys v0.4.16 // indirect
 	github.com/nats-io/nuid v1.0.1 // indirect
 	golang.org/x/crypto v0.57.0 // indirect
 	golang.org/x/sys v0.48.0 // indirect
-	golang.org/x/time v0.15.0 // indirect
+	golang.org/x/time v0.16.0 // indirect
 )
+
+replace git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun => ./buildrun
+
+require (
+	git.novox.be/novox/mesh-contracts/go/seats/containerimageregistry v0.0.0-20261104174344-ae5266e77639
+	git.novox.be/novox/mesh-contracts/go/seats/gopackageregistry v0.0.0-20261104174344-ae5266e77639
+	git.novox.be/novox/mesh-contracts/go/seats/nodeengine v0.0.0-20261104174344-ae5266e77639
+	git.novox.be/novox/mesh-contracts/go/seats/npmpackageregistry v0.0.0-20261104174344-ae5266e77639
+	git.novox.be/novox/mesh-contracts/go/seats/ociartifactregistry v0.0.0-20261104174344-ae5266e77639
+	git.novox.be/novox/mesh-delivery/sdk v0.0.0-00010101000000-000000000000
+)
+
+require (
+	git.novox.be/novox/mesh-contracts/go/clients/containerimageregistryclient v0.0.0-20261104174344-ae5266e77639 // indirect
+	git.novox.be/novox/mesh-contracts/go/clients/gopackageregistryclient v0.0.0-20261104174344-ae5266e77639 // indirect
+	git.novox.be/novox/mesh-contracts/go/clients/npmpackageregistryclient v0.0.0-20261104174344-ae5266e77639 // indirect
+	git.novox.be/novox/mesh-contracts/go/clients/ociartifactregistryclient v0.0.0-20261104174344-ae5266e77639 // indirect
+)
+
+replace git.novox.be/novox/mesh-delivery/sdk => ../../sdk

modules/mesh-delivery-builder/go.sum

@@ -1,15 +1,37 @@
-git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028193502-f91340fe82ef h1:ggwHXCvAOhBCKAY+ErehKEhu/IQTS4poJBRDokGYnDc=
-git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028193502-f91340fe82ef/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
-github.com/antithesishq/antithesis-sdk-go v0.7.0-default-no-op h1:Z/MZK75wC/NSrkgqeNIa7jexam9uWzhLmFTSCPI/kn0=
-github.com/antithesishq/antithesis-sdk-go v0.7.0-default-no-op/go.mod h1:FQyySiasQQM8735Ddel3MRojmy4dA1IqCeyJ5jmPMbI=
+git.novox.be/novox/mesh-catalog/modules/mesh-build-go/buildstep v0.0.0-20261104174638-125929dbc459 h1:DA4SFG/gKyG+aPJbfUpAUad2VeITIiKjJ6qOPmDhSA8=
+git.novox.be/novox/mesh-catalog/modules/mesh-build-go/buildstep v0.0.0-20261104174638-125929dbc459/go.mod h1:zR1HsAKZVbQsBIY5wPyrqI2WHInK268tITzGl2oqHro=
+git.novox.be/novox/mesh-contracts/go v0.0.0-20261104174344-ae5266e77639 h1:Zt7CfWt2S2W/fVgWNyW2u2+xwz051LXvGxVTNIyfhdM=
+git.novox.be/novox/mesh-contracts/go v0.0.0-20261104174344-ae5266e77639/go.mod h1:0dD1XEJBJ0G5UYDQxSZI84nuujb6m3tOpJl4C8rQVvg=
+git.novox.be/novox/mesh-contracts/go/clients/containerimageregistryclient v0.0.0-20261104174344-ae5266e77639 h1:I6uVDO9E+i3D9/n6KQ2RWYRs3kXYCqueiKXynifQo8w=
+git.novox.be/novox/mesh-contracts/go/clients/containerimageregistryclient v0.0.0-20261104174344-ae5266e77639/go.mod h1:ER2NVrd81uJo1lN0YCGA7OBxL910IHRgWYtxpsnHGF0=
+git.novox.be/novox/mesh-contracts/go/clients/gopackageregistryclient v0.0.0-20261104174344-ae5266e77639 h1:Rs5jOa7EWlpKuaH6+ExyGLN9k9UUi8N7upP9Ac3k+GY=
+git.novox.be/novox/mesh-contracts/go/clients/gopackageregistryclient v0.0.0-20261104174344-ae5266e77639/go.mod h1:fNfjFkP1+suYb12HJkapQe5W3cF98JsTcLBI/syoLHc=
+git.novox.be/novox/mesh-contracts/go/clients/npmpackageregistryclient v0.0.0-20261104174344-ae5266e77639 h1:VG+sZltyBIKrd9cwFJyKkInz04SxWBxUlJWfAuo6774=
+git.novox.be/novox/mesh-contracts/go/clients/npmpackageregistryclient v0.0.0-20261104174344-ae5266e77639/go.mod h1:Nq7glLZSZ8zOLTh1pXDnKZi+MxsMRyHw/bZODC3mvrY=
+git.novox.be/novox/mesh-contracts/go/clients/ociartifactregistryclient v0.0.0-20261104174344-ae5266e77639 h1:ROS9UG/Dg0NpsaDuEmDFV9CsIC1R92sOm3QauF7IvL0=
+git.novox.be/novox/mesh-contracts/go/clients/ociartifactregistryclient v0.0.0-20261104174344-ae5266e77639/go.mod h1:/Pke1v2VnSFcR8ic+fo/kNCg3JFYK6ILTal72Ca9520=
+git.novox.be/novox/mesh-contracts/go/seats/containerimageregistry v0.0.0-20261104174344-ae5266e77639 h1:5HeZzk6tKzcSwVivD3IcIvQ/2WIvysZvNvNKyq/oIBA=
+git.novox.be/novox/mesh-contracts/go/seats/containerimageregistry v0.0.0-20261104174344-ae5266e77639/go.mod h1:pPxwhTMb3hIk7UUrBicJnGQCqfTEoBGJvNFspEK2U18=
+git.novox.be/novox/mesh-contracts/go/seats/gopackageregistry v0.0.0-20261104174344-ae5266e77639 h1:oAXU1t8A1rGIr82JPBaNYSGLicXqhWglKaEAtPmrD0c=
+git.novox.be/novox/mesh-contracts/go/seats/gopackageregistry v0.0.0-20261104174344-ae5266e77639/go.mod h1:Y5kgBh0hBbL/hgc+abCF9Vbhov+vCsB0ckpRzUw1D+0=
+git.novox.be/novox/mesh-contracts/go/seats/nodeengine v0.0.0-20261104174344-ae5266e77639 h1:YQ6eJvc+RYUVIVf+oX+R4TC1dYL8TLLMZ0/JPDU1tp4=
+git.novox.be/novox/mesh-contracts/go/seats/nodeengine v0.0.0-20261104174344-ae5266e77639/go.mod h1:TB20TsQuOd5aer+cXL6PbaYyg2RvgL1R4MzD61Oks3A=
+git.novox.be/novox/mesh-contracts/go/seats/npmpackageregistry v0.0.0-20261104174344-ae5266e77639 h1:ILh7uctNwgx/89qHoR/H2kz5TpWeKEeIH0O2pDPE7Iw=
+git.novox.be/novox/mesh-contracts/go/seats/npmpackageregistry v0.0.0-20261104174344-ae5266e77639/go.mod h1:JRtTjIjMTkzn59IN4vCYei9ZwJGFnN1Puwame4V/sD0=
+git.novox.be/novox/mesh-contracts/go/seats/ociartifactregistry v0.0.0-20261104174344-ae5266e77639 h1:+bkN8op2yrAlBYrOB+hYnIoIZkbjXsNmc/4//uMnL4E=
+git.novox.be/novox/mesh-contracts/go/seats/ociartifactregistry v0.0.0-20261104174344-ae5266e77639/go.mod h1:ooQa2CiP8JOvhP0bdQvwurV5wskRE7Cm68ecURBbCwU=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261104174359-05b3e2e1b94f h1:jDsfDMd48MXY9Zershc3eRxnhmx2sSpUfQkLq5jAIds=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261104174359-05b3e2e1b94f/go.mod h1:08OomDXdwVN8/87nyDtv5R3rH/6LoP8SFFXz30bTYCM=
+github.com/antithesishq/antithesis-sdk-go v0.8.0-default-no-op h1:1BOWQJweNyvZMlpAHXGLiZQn9S+QXGcz3xh94lC0w6E=
+github.com/antithesishq/antithesis-sdk-go v0.8.0-default-no-op/go.mod h1:FQyySiasQQM8735Ddel3MRojmy4dA1IqCeyJ5jmPMbI=
 github.com/google/go-tpm v0.9.8 h1:slArAR9Ft+1ybZu0lBwpSmpwhRXaa85hWtMinMyRAWo=
 github.com/google/go-tpm v0.9.8/go.mod h1:h9jEsEECg7gtLis0upRBQU+GhYVH6jMjrFxI8u6bVUY=
-github.com/klauspost/compress v1.20.0 h1:a3C1ke2ohxFymNlb2HWAHjDeKCI90scRskErZkR0ezA=
-github.com/klauspost/compress v1.20.0/go.mod h1:LUdAzn7YLVvxLpc7y3V1m40wESHTgc1422pwwBSKYuI=
+github.com/klauspost/compress v1.20.1 h1:T7kKElXUMXrUJ2E9QhQhxFtcK5rPyLdsGZvdbLMPdiQ=
+github.com/klauspost/compress v1.20.1/go.mod h1:LUdAzn7YLVvxLpc7y3V1m40wESHTgc1422pwwBSKYuI=
 github.com/minio/highwayhash v1.0.4 h1:asJizugGgchQod2ja9NJlGOWq4s7KsAWr5XUc9Clgl4=
 github.com/minio/highwayhash v1.0.4/go.mod h1:GGYsuwP/fPD6Y9hMiXuapVvlIUEhFhMTh0rxU3ik1LQ=
-github.com/nats-io/jwt/v2 v2.8.1 h1:V0xpGuD/N8Mi+fQNDynXohVvp7ZztevW5io8CUWlPmU=
-github.com/nats-io/jwt/v2 v2.8.1/go.mod h1:nWnOEEiVMiKHQpnAy4eXlizVEtSfzacZ1Q43LIRavZg=
+github.com/nats-io/jwt/v2 v2.8.2 h1:XXRgB60MSTnqsRwejQurVDs/hcv2dkt+86GjI+I/bMc=
+github.com/nats-io/jwt/v2 v2.8.2/go.mod h1:Ag/56sq9OblL4JgdYufDd16Egb17Kr/8WwwuO/forVc=
 github.com/nats-io/nats-server/v2 v2.11.17 h1:GKEghcFK6A+aFx11Yf1LjgLC3txAwvyhnYzhBIQZA8I=
 github.com/nats-io/nats-server/v2 v2.11.17/go.mod h1:B1sFVz4StNosQ903ak4N1G01Fl/9f8e06mXpFIE2K24=
 github.com/nats-io/nats.go v1.54.0 h1:vsXoOxjHp/GmPUN+EcI7uOf/uB+iAP+kEsAFNQN0yzA=
@@ -23,5 +45,5 @@ golang.org/x/crypto v0.57.0/go.mod h1:Fdz0i5U6CoizGwLda9DttjSk6qlZo25zYNtR+ycvuZ
 golang.org/x/sys v0.21.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/sys v0.48.0 h1:bbX/i/6MgT9BVLM9RT1thmxL04yeTAhbEz4SyadbXoo=
 golang.org/x/sys v0.48.0/go.mod h1:hNLxWAXmnKAxqDtdwIYC4bM9oQPEecfsnNMuSxOs3og=
-golang.org/x/time v0.15.0 h1:bbrp8t3bGUeFOx08pvsMYRTCVSMk89u4tKbNOZbp88U=
-golang.org/x/time v0.15.0/go.mod h1:Y4YMaQmXwGQZoFaVFk4YpCt4FLQMYKZe9oeV/f4MSno=
+golang.org/x/time v0.16.0 h1:vMb6ptszcQMkcwiRTAuNNU50gom6++Q/6gY2hDM6VDE=
+golang.org/x/time v0.16.0/go.mod h1:rVKOqvZeKvrDKTQiAHJ7wmwP0RzleSphoEA9RcdLA0s=

modules/mesh-delivery-builder/internal/build/announce.go

@@ -0,0 +1,53 @@
+package build
+
+import (
+	"context"
+	"errors"
+	"fmt"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// **A done build is announced again by hand** (recovery of photos and link2pay on novox, 2026-10-29). The controller takes a
+// build in when a write of the build key reaches its take-in consumer, and composes then; a done key is never written again
+// by the builder, so a composition or a grant lost afterwards could not be made again by any tool. AnnounceAgain writes the
+// done key again with its own bytes, as a new revision of the same key: its content, state, artifacts and manifest stay
+// identical, and only the write is new. Who asked and why is in the builder's log and in the reasks answer.
+
+// AnnounceAgain rewrites the done key of module at fp unchanged, as a new revision, and answers the revision. A key that is
+// not done is refused with why: failed (builder_build_again builds it) or waiting (builder_ask_again).
+func (b *Builder) AnnounceAgain(ctx context.Context, module, fp, why, by string) BuildAgainResult {
+	b.init()
+	key, err := delivery.BuilderBuildKey(module, fp)
+	if err != nil {
+		return BuildAgainResult{Refused: err.Error()}
+	}
+	value, rev, found, err := b.Claimer.Store.Get(ctx, key)
+	if err != nil {
+		return BuildAgainResult{Refused: fmt.Sprintf("%s cannot be read: %v", key, err)}
+	}
+	if !found {
+		return BuildAgainResult{Refused: fmt.Sprintf("%s has no build key: nothing to announce", key)}
+	}
+	cur, err := delivery.DecodeBuilderBuild(value)
+	if err != nil {
+		return BuildAgainResult{Refused: fmt.Sprintf("%s holds what is not a build: %v", key, err)}
+	}
+	switch cur.State {
+	case delivery.BuildDone:
+	case delivery.BuildFailed:
+		return BuildAgainResult{Refused: fmt.Sprintf("%s is failed, not done: %s builds it again", key, BuildAgainTool)}
+	default:
+		return BuildAgainResult{Refused: fmt.Sprintf("%s is %q, not done: %s asks its waiting asks again", key, cur.State, AskAgainTool)}
+	}
+	// Compare-and-set at the revision read: a build written meanwhile is not overwritten.
+	nrev, err := b.Claimer.Store.Update(ctx, key, value, rev)
+	if err != nil {
+		if errors.Is(err, ErrConflict) {
+			return BuildAgainResult{Refused: fmt.Sprintf("%s changed while it was announced: read it again", key)}
+		}
+		return BuildAgainResult{Refused: fmt.Sprintf("%s could not be written: %v", key, err)}
+	}
+	b.logf("%s: done, announced again by %s (revision %d): %s", key, by, nrev, why)
+	return BuildAgainResult{Revision: nrev}
+}

modules/mesh-delivery-builder/internal/build/announce_test.go

@@ -0,0 +1,49 @@
+package build
+
+import (
+	"bytes"
+	"context"
+	"strings"
+	"testing"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+func TestAnnounceAgainRewritesOnlyADoneKeyUnchanged(t *testing.T) { // recovery of photos and link2pay, 2026-10-29
+	for _, c := range []struct {
+		name   string
+		key    *delivery.BuilderBuild
+		fp     string
+		refuse string
+	}{
+		{name: "a done key is written again, unchanged, as a new revision", key: &delivery.BuilderBuild{State: delivery.BuildDone, Step: "built"}},
+		{name: "a failed key is refused, builder_build_again is for it", refuse: "builder_build_again", key: &delivery.BuilderBuild{State: delivery.BuildFailed, Error: "x"}},
+		{name: "a building key is refused, builder_ask_again is for it", refuse: "builder_ask_again", key: &delivery.BuilderBuild{State: delivery.BuildBuilding, By: "novox.builder", Step: "asked"}},
+		{name: "a key with no build is refused", refuse: "has no build key"},
+		{name: "a fingerprint that is not one is refused", refuse: "fingerprint", fp: "nope"},
+	} {
+		t.Run(c.name, func(t *testing.T) {
+			r := newRig(t, goBundle)
+			var rev uint64
+			if c.key != nil {
+				c.key.Manifest = manifestD
+				rev = putBuild(t, r.st, r.key, *c.key)
+			}
+			before := bytes.Clone(r.st.vals[r.key])
+			fp := fp1
+			if c.fp != "" {
+				fp = c.fp
+			}
+			res := r.b.AnnounceAgain(context.Background(), "m", fp, "grant lost", "shanks.lead")
+			if c.refuse != "" {
+				if !strings.Contains(res.Refused, c.refuse) || res.Revision != 0 || r.st.revs[r.key] != rev || !bytes.Equal(r.st.vals[r.key], before) {
+					t.Fatalf("answer %+v, key at revision %d (was %d); want refused with %q and nothing written", res, r.st.revs[r.key], rev, c.refuse)
+				}
+				return
+			}
+			if res.Refused != "" || res.Revision <= rev || r.st.revs[r.key] != res.Revision || !bytes.Equal(r.st.vals[r.key], before) {
+				t.Fatalf("answer %+v, key at revision %d (was %d); want a new revision and the same bytes", res, r.st.revs[r.key], rev)
+			}
+		})
+	}
+}

modules/mesh-delivery-builder/internal/build/askagain.go

@@ -6,13 +6,14 @@ import (
 	"fmt"
 	"regexp"
 	"slices"
+	"sort"
 	"strconv"
 	"strings"
 	"time"
 
+	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun"
 	"git.novox.be/novox/mesh-sdk/go/buildstep"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
 )
 
 // **An ask that can no longer be answered is asked again** (novox/hq issue 1945). A build seat's stream gives an ask up
@@ -177,6 +178,42 @@ func (b *Builder) drop(ctx context.Context, ask delivery.StepAsk, old string) {
 	}
 }
 
+// DefaultDeclineBound is how long one ask may go on being declined, from its first decline, before its key fails (the
+// checker's DefaultDeclineBound, issue 890); DefaultDeclinePause is how long the builder waits before it puts a declined
+// ask again, so a lone node off the agreed toolchain cannot spin on it.
+const (
+	DefaultDeclineBound = 30 * time.Minute
+	DefaultDeclinePause = 5 * time.Second
+)
+
+func (b *Builder) declineBound() time.Duration {
+	if b.DeclineBound > 0 {
+		return b.DeclineBound
+	}
+	return DefaultDeclineBound
+}
+
+func (b *Builder) declinePause() time.Duration {
+	if b.DeclinePause != 0 {
+		return max(b.DeclinePause, 0)
+	}
+	return DefaultDeclinePause
+}
+
+// declinedWords names the nodes that declined an ask and why, in the order of their names.
+func declinedWords(by map[string]string) string {
+	nodes := make([]string, 0, len(by))
+	for n := range by {
+		nodes = append(nodes, n)
+	}
+	sort.Strings(nodes)
+	var parts []string
+	for _, n := range nodes {
+		parts = append(parts, n+": "+by[n])
+	}
+	return strings.Join(parts, "; ")
+}
+
 func (b *Builder) askings() int {
 	if b.Askings > 0 {
 		return b.Askings
@@ -255,6 +292,8 @@ func (b *Builder) unlisten(key, language string, c chan string) {
 var (
 	errCheck = errors.New("the check bound passed")
 	errAgain = errors.New("asked again")
+	// errDeclined: a build node on another toolchain than the agreed one sat out of the ask (ADR 0584 clause 2).
+	errDeclined = errors.New("declined")
 )
 
 type byHand struct{ why string }
@@ -268,11 +307,42 @@ func (b *Builder) answer(ctx context.Context, l *lane, ask delivery.StepAsk, ask
 	again := b.listen(key, ask.Language)
 	defer b.unlisten(key, ask.Language, again)
 	asking := askingOf(asked.step, l.module)
+	var firstDecline time.Time
+	declines := map[string]string{} // node -> why it declined, the last
 	for {
 		step, why, err := b.waitOnce(ctx, ask, again)
 		switch {
 		case errors.Is(err, errCheck):
 			continue
+		case errors.Is(err, errDeclined):
+			// Not an asking: a node that sits out would use them all while it idles and pulls the ask again at once.
+			// Bounded by time from the first decline, then failed loudly naming the nodes and their reasons (as the
+			// checker's decline loop is, issue 890).
+			now := b.now()
+			if firstDecline.IsZero() {
+				firstDecline = now
+			}
+			declines[step.Node] = why
+			if bound := b.declineBound(); now.Sub(firstDecline) > bound {
+				return step, ask, fmt.Errorf("the ask %s of %s was declined for %s and no build node took it: %s", ask.ID, l.module, bound.Round(time.Second), declinedWords(declines))
+			}
+			// The pause is a context's bound, not a timer (ADR 0437 §8).
+			pause, stop := context.WithTimeout(ctx, b.declinePause())
+			<-pause.Done()
+			stop()
+			if ctx.Err() != nil {
+				return step, ask, ctx.Err()
+			}
+			old := ask.ID
+			ask.ID, ask.At = buildstep.NewID(), time.Now()
+			if err := asked.note(ctx, ask.Language, ask.ID, fmt.Sprintf("put %s again after %s declined it", l.module, step.Node)); err != nil {
+				return step, ask, fmt.Errorf("the ask of %s put again after a decline could not be written to the key: %w", l.module, err)
+			}
+			if err := b.Asks.Put(ctx, ask); err != nil {
+				return step, ask, err
+			}
+			b.drop(ctx, ask, old)
+			b.logf("%s: the ask %s of %s was declined on %s and is put again as %s: %s", key, old, l.module, step.Node, ask.ID, why)
 		case errors.Is(err, errAgain):
 			if asking >= b.askings() {
 				return step, ask, fmt.Errorf("the ask %s could not be answered and was asked %d times, the most it is: %s", ask.ID, asking, why)
@@ -317,6 +387,11 @@ func (b *Builder) waitOnce(ctx context.Context, ask delivery.StepAsk, again <-ch
 		defer stop()
 	}
 	step, err := b.Asks.Wait(wait, ask)
+	if _, declined := delivery.DeclinedOf(step); err == nil && declined {
+		// A build node off the agreed toolchain sat out (ADR 0584 clause 2). It is no asking: answer() puts the ask again
+		// after a pause, within DeclineBound.
+		return step, step.Reason, errDeclined
+	}
 	if err == nil && buildrun.IsLost(step) {
 		// The build seat gave the ask up (issue 734): it can no longer be answered, so it is asked again now, with the
 		// words of why, not at the check bound.

modules/mesh-delivery-builder/internal/build/askfake_test.go

@@ -0,0 +1,94 @@
+package build
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"maps"
+	"strings"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// The build runner a build node runs an ask with is mesh-build-go's (novox/hq ADR 0593 §1), another repository's,
+// which the builder does not import. These tests run an ask as the builder needs it run: fetch once at the job's
+// fetch arguments with its package versions, build or copy each artifact, answer each one's digest and reference. They
+// test the builder, not the runner.
+
+// stepFunc is one step of a build module, as its tool answers it.
+type stepFunc func(ctx context.Context, args map[string]any) (any, error)
+
+// askSteps are a build module's steps an ask is run with.
+type askSteps struct{ Fetch, Build, Copy stepFunc }
+
+// runAsk runs a build ask with steps and answers its delivery.BuildAnswer, or the error that fails the step.
+func runAsk(ctx context.Context, steps askSteps, ask delivery.StepAsk) (any, error) {
+	if ask.Build == nil {
+		return nil, fmt.Errorf("the ask %s holds no build job", ask.ID)
+	}
+	job := *ask.Build
+	fetch := job.Fetch
+	if len(ask.Packages) > 0 && fetch != nil {
+		fetch = maps.Clone(fetch)
+		fetch["packages"] = maps.Clone(ask.Packages)
+	}
+	answer := delivery.BuildAnswer{}
+	workspace := ""
+	for _, a := range job.Artifacts {
+		var out any
+		var err error
+		if a.From != "" {
+			if steps.Copy == nil {
+				return nil, fmt.Errorf("this build module copies no artifact (%s)", a.Artifact)
+			}
+			out, err = steps.Copy(ctx, map[string]any{"module": job.Module, "artifact": a.Artifact, "from": a.From})
+		} else {
+			if workspace == "" {
+				raw, err := asRaw(steps.Fetch(ctx, fetch))
+				if err != nil {
+					return nil, err
+				}
+				var f struct {
+					Workspace string   `json:"workspace"`
+					Merge     string   `json:"merge"`
+					Conflicts []string `json:"conflicts"`
+				}
+				if err := json.Unmarshal(raw, &f); err != nil || f.Workspace == "" {
+					return nil, fmt.Errorf("the fetch answered no workspace: %s", raw)
+				}
+				if _, candidate := fetch["base"]; candidate && (len(f.Conflicts) > 0 || f.Merge == "") {
+					return nil, fmt.Errorf("the head does not merge into the trunk: %s", strings.Join(f.Conflicts, ", "))
+				}
+				workspace = f.Workspace
+			}
+			args := map[string]any{"workspace": workspace, "module": job.Path, "artifact": a.Artifact}
+			if job.Publish {
+				args["publish"] = true
+			}
+			out, err = steps.Build(ctx, args)
+		}
+		raw, err := asRaw(out, err)
+		if err != nil {
+			return nil, fmt.Errorf("%s: %w", a.Artifact, err)
+		}
+		var built struct {
+			Digest    string `json:"digest"`
+			Reference string `json:"reference"`
+		}
+		if err := json.Unmarshal(raw, &built); err != nil || built.Digest == "" {
+			return nil, fmt.Errorf("the build of %s answered no digest: %s", a.Artifact, raw)
+		}
+		answer.Artifacts = append(answer.Artifacts, delivery.AskBuilt{Artifact: a.Artifact, Digest: built.Digest, Reference: built.Reference})
+	}
+	return answer, nil
+}
+
+func asRaw(v any, err error) (json.RawMessage, error) {
+	if err != nil {
+		return nil, err
+	}
+	if r, ok := v.(json.RawMessage); ok {
+		return r, nil
+	}
+	return json.Marshal(v)
+}

modules/mesh-delivery-builder/internal/build/buildagain.go

@@ -7,8 +7,8 @@ import (
 	"strings"
 	"time"
 
+	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
 )
 
 // **A failed key is built again by hand** (novox/hq issue 1126 note 72; ADR 0429 clause 18: "a fingerprint is built again

modules/mesh-delivery-builder/internal/build/candidates.go

@@ -5,8 +5,8 @@ import (
 	"fmt"
 	"sort"
 
+	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
 )
 
 // How a candidate's fingerprint is built (novox/hq ADR 0484 clause 3, issue 1684): the indexer writes, for each module a
@@ -68,7 +68,7 @@ func (b *Builder) considerCandidate(ctx context.Context, c delivery.Candidate) {
 				continue
 			}
 			m := delivery.Module{Repository: p.Repository, Commit: p.Head.Head, FP2: cm.FP2, Manifest: cm.Manifest, Path: trunk.Path,
-				Toolchains: b.agreedFor(ctx, cm.Manifest)}
+				Toolchains: b.agreedFor(ctx, cm.Manifest), Packages: cm.Packages} // the group's package heads (ADR 0573 §4)
 			if len(cm.Paths) > 0 {
 				// The named paths' objects the preview gave it: the fetch names the paths (runLane, ADR 0499 clause 4).
 				m.Inputs2 = &delivery.KeptInputs2{Paths: cm.Paths}

modules/mesh-delivery-builder/internal/build/claim.go

@@ -8,9 +8,9 @@ import (
 	"sort"
 	"strings"
 
+	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun"
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
 )
 
 // ErrConflict is what a Store answers when a Create finds the key or an Update finds another revision than the one given.
@@ -61,8 +61,8 @@ type ClaimOptions struct {
 	// a package's reference. A key queued waiting for a version (BuilderBuild.Waits) is taken only once it is (ADR 0500
 	// clause 6). Nil means none is.
 	Published func(ref string) bool
-	// Stored answers which of the references given the artifact store no longer holds (the controller's verb held,
-	// mesh-sdk delivery.HeldVerb; novox/hq issue 1937). A done key of the trunk's fingerprint is asked before it is left
+	// Stored answers which of the references given the artifact store no longer holds (the seat mesh-artifact-sweep's verb held,
+	// novox/hq ADR 0571 §2, issue 1937). A done key of the trunk's fingerprint is asked before it is left
 	// done: the store's nightly collector deletes a blob nothing holds, and a key the controller never took in holds
 	// nothing, so a key whose blob is gone is claimed building as a new revision and built again. Nil asks nothing.
 	Stored func(ctx context.Context, references []string) (gone []string, err error)

modules/mesh-delivery-builder/internal/build/claim_test.go

@@ -114,12 +114,11 @@ func TestClaimCreatesTheKeyBuildingAndASecondBuilderGetsNothing(t *testing.T) {
 	if second, err := b.Claim(context.Background(), "m", fp1, hex64('a'), ClaimOptions{}); err != nil || second != nil {
 		t.Errorf("second builder's claim = %v, %v, want none: the same source is never built twice", second, err)
 	}
-}
 
-func TestClaimLosingTheCreateRaceGetsNothing(t *testing.T) { // 1607/AC3
-	st := newMem()
+	// A claim losing the create race gets nothing (merged into this test for the test budget, design 51).
+	st = newMem()
 	st.before = func() { seed(t, st, delivery.BuilderBuild{State: delivery.BuildBuilding, By: "novox.b"}) }
-	got, err := Claimer{Store: st, By: "novox.a"}.Claim(context.Background(), "m", fp1, "", ClaimOptions{})
+	got, err = Claimer{Store: st, By: "novox.a"}.Claim(context.Background(), "m", fp1, "", ClaimOptions{})
 	if err != nil || got != nil {
 		t.Errorf("claim = %v, %v, want none: the create failed because the key exists", got, err)
 	}
@@ -197,12 +196,11 @@ func TestFinishMovesTheKeyByCompareAndSetAndWritesOnlyADifferentValue(t *testing
 	if st.writes != writes {
 		t.Errorf("the same value was written again (%d writes, was %d)", st.writes, writes)
 	}
-}
 
-func TestFinishAfterTheKeyChangedIsAConflictNotAnOverwrite(t *testing.T) { // 1607/AC3
-	st := newMem()
-	c := Claimer{Store: st, By: "novox.a"}
-	got, _ := c.Claim(context.Background(), "m", fp1, "", ClaimOptions{})
+	// Finish after the key changed is a conflict, not an overwrite (merged into this test for the test budget).
+	st = newMem()
+	c = Claimer{Store: st, By: "novox.a"}
+	got, _ = c.Claim(context.Background(), "m", fp1, "", ClaimOptions{})
 	st.put(got.Key, []byte(`{"v":1,"state":"failed","error":"someone else"}`))
 	err := c.Finish(context.Background(), got, delivery.BuilderBuild{State: delivery.BuildFailed, Error: "mine"})
 	if !errors.Is(err, ErrConflict) {

modules/mesh-delivery-builder/internal/build/fixtures_test.go

@@ -29,7 +29,7 @@ func captured(t *testing.T, name string) json.RawMessage {
 	return step.Result
 }
 
-// The captured image steps, run as a pulled ask runs them (buildstep.RunAsk), answer what the builder reads: the trunk's
+// The captured image steps, run as a pulled ask runs them (runAsk), answer what the builder reads: the trunk's
 // build its digest and reference, a candidate's its digest and no reference (issue 1887 A4a).
 func TestCapturedImageStepsDecodeWithTheBuildersOwnTypes(t *testing.T) { // review r2, mesh-catalog 2; ADR 0487 clause 1
 	for _, tc := range []struct {
@@ -37,7 +37,7 @@ func TestCapturedImageStepsDecodeWithTheBuildersOwnTypes(t *testing.T) { // revi
 		publish bool
 		ref     bool
 	}{{"build-trunk.json", true, true}, {"build-candidate.json", false, false}} {
-		steps := buildstep.AskSteps{
+		steps := askSteps{
 			Fetch: func(context.Context, map[string]any) (any, error) {
 				return json.RawMessage(captured(t, "fetch.json")), nil
 			},
@@ -47,7 +47,7 @@ func TestCapturedImageStepsDecodeWithTheBuildersOwnTypes(t *testing.T) { // revi
 			At: time.Now(), Build: &delivery.BuildJob{Module: "m", Path: "modules/m", Publish: tc.publish,
 				Fetch:     map[string]any{"repository": "novox/mesh-catalog", "commit": strings.Repeat("a", 40)},
 				Artifacts: []delivery.AskArtifact{{Artifact: "server"}}}}
-		out, err := buildstep.RunAsk(context.Background(), steps, ask)
+		out, err := runAsk(context.Background(), steps, ask)
 		if err != nil {
 			t.Fatalf("%s: %v", tc.build, err)
 		}

modules/mesh-delivery-builder/internal/build/imports_test.go

@@ -0,0 +1,78 @@
+package build
+
+import (
+	"encoding/json"
+	"strings"
+	"sync"
+	"testing"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// ADR 0593 §2 (F3): the imports a Go build module answers at a build's end reach the done key and the log's end entry,
+// where the indexer keeps them on the module.
+func importsABuildAnswersReachTheDoneKeyAndTheLog(t *testing.T) {
+	r := newRig(t, goBundle)
+	imports := []string{"git.novox.be/novox/mesh-sdk/go", "git.novox.be/novox/mesh-sdk/go/announce"}
+	r.asks.Answer = func(a delivery.StepAsk) delivery.Step {
+		step := r.answer(a)
+		var answer map[string]any
+		if err := json.Unmarshal(step.Result, &answer); err == nil && a.Language == "go" {
+			answer["imports"] = imports
+			step.Result, _ = json.Marshal(answer)
+		}
+		return step
+	}
+	var logged []delivery.BuildLogEntry
+	var mu sync.Mutex
+	r.b.Node, r.b.Log = "novox", func(e delivery.BuildLogEntry) { mu.Lock(); logged = append(logged, e); mu.Unlock() }
+	v := r.consider(t, "modules/m")
+	if v.State != delivery.BuildDone || strings.Join(v.Imports, ",") != strings.Join(imports, ",") {
+		t.Fatalf("done key %+v, want the imports", v)
+	}
+	if len(logged) != 2 || strings.Join(logged[1].Imports, ",") != strings.Join(imports, ",") || len(logged[0].Imports) != 0 {
+		t.Fatalf("log %+v, want the imports on the end alone", logged)
+	}
+}
+
+// Design 26 (the lead's ruling on A2i's finding 2): the out-of-step files a contracts module's build module answers, in a
+// failed step's result too, reach the log's end entry, sorted and each once, where the indexer raises its finding; a
+// build that answers none names none.
+func outOfStepFilesABuildAnswersReachTheLog(t *testing.T) {
+	for _, row := range []struct {
+		name  string
+		fail  bool
+		files []string
+		want  string
+	}{
+		{"a passed build naming files", false, []string{"go/b.go", "go/a.go", "go/b.go"}, "go/a.go,go/b.go"},
+		{"a failed build naming files", true, []string{"ts/x.ts"}, "ts/x.ts"},
+		{"a build naming none", false, nil, ""},
+	} {
+		t.Run(row.name, func(t *testing.T) {
+			r := newRig(t, goBundle)
+			r.asks.Answer = func(a delivery.StepAsk) delivery.Step {
+				step := r.answer(a)
+				answer := map[string]any{}
+				_ = json.Unmarshal(step.Result, &answer)
+				if row.files != nil {
+					answer["out-of-step"] = row.files
+				}
+				step.Result, _ = json.Marshal(answer)
+				if row.fail {
+					step.State, step.Reason = delivery.StepFailed, "the generated files are out of step"
+				}
+				return step
+			}
+			var logged []delivery.BuildLogEntry
+			var mu sync.Mutex
+			r.b.Node, r.b.Log = "novox", func(e delivery.BuildLogEntry) { mu.Lock(); logged = append(logged, e); mu.Unlock() }
+			r.consider(t, "modules/m")
+			mu.Lock()
+			defer mu.Unlock()
+			if len(logged) != 2 || strings.Join(logged[1].OutOfStep, ",") != row.want || len(logged[0].OutOfStep) != 0 {
+				t.Fatalf("log %+v, want the end naming %q", logged, row.want)
+			}
+		})
+	}
+}

modules/mesh-delivery-builder/internal/build/numbers.go

@@ -0,0 +1,140 @@
+package build
+
+import (
+	"context"
+	"fmt"
+	"strconv"
+	"time"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+
+	"mesh-delivery-builder/internal/versions"
+)
+
+// Numbers numbers a trunk build at its claim (novox/hq design 51 *The versions*, ADR 0606, ADR 0617 §1) and records the
+// digests it was built with. Nil numbers nothing.
+type Numbers interface {
+	// tag is a check's build's tag (TagOf), empty for a trunk build; done the digests of its key when it is done already
+	// (versions.BuildClaim.Done), nil otherwise.
+	Number(ctx context.Context, module string, m delivery.Module, plan Plan, tag string, done map[string]string) (versions.Numbering, error)
+	Built(ctx context.Context, module string, m delivery.Module, plan Plan, got versions.Numbering, made []delivery.BuiltArtifact) error
+}
+
+// VersionNumbers is Numbers over the builder's state versions.
+type VersionNumbers struct {
+	N *versions.Numberer
+	// TagNumbered is told the versions a check's build of a tag ask's head was numbered (the ask is then marked numbered
+	// in tag-asks, design 51 *Tagged versions*); nil tells nobody.
+	TagNumbered func(ctx context.Context, c versions.BuildClaim, got versions.Numbering)
+}
+
+// ClaimOf is the claim a module value's trunk build is numbered by: a package per source revision (Src), the rest per
+// fingerprint, in merge order (Src).
+func ClaimOf(module string, m delivery.Module, plan Plan) versions.BuildClaim {
+	c := versions.BuildClaim{Module: module, Path: m.Path, Repository: delivery.RepositoryName(m.Repository), Fingerprint: m.FP2,
+		Commit: m.Commit, Merge: m.Src}
+	if m.Src != 0 {
+		c.Revision = strconv.FormatUint(m.Src, 10)
+	}
+	for _, t := range plan.Tasks {
+		c.Artifacts = append(c.Artifacts, versions.ClaimArtifact{Artifact: t.Artifact, Kind: t.Kind, Language: t.Language})
+	}
+	return c
+}
+
+func (v VersionNumbers) Number(ctx context.Context, module string, m delivery.Module, plan Plan, tag string, done map[string]string) (versions.Numbering, error) {
+	c := ClaimOf(module, m, plan)
+	c.Done = done
+	if tag != "" {
+		// A check's build of a head a tag ask names: its packages tagged, below the next version (design 51 *Tagged versions*).
+		c.Tag, c.Head, c.Revision, c.Merge = tag, m.Commit, "", 0
+	}
+	got, err := v.N.Number(ctx, c)
+	if err == nil && tag != "" && len(got.Versions) > 0 && v.TagNumbered != nil {
+		v.TagNumbered(ctx, c, got)
+	}
+	return got, err
+}
+
+func (v VersionNumbers) Built(ctx context.Context, module string, m delivery.Module, plan Plan, got versions.Numbering, made []delivery.BuiltArtifact) error {
+	digests := map[string]string{}
+	for _, a := range made {
+		digests[a.Name] = a.Digest
+	}
+	return v.N.Built(ctx, ClaimOf(module, m, plan), got, digests)
+}
+
+// TagOf answers the cleaned tag a kept tag ask names for a repository's head (the builder's state tag-asks, design 51
+// *Tagged versions*): a check's build of that head numbers its packages tagged at its claim.
+type TagOf func(ctx context.Context, repository, head string) (tag string, ok bool)
+
+// number numbers a build before its claim, a trunk build's artifacts or a check's build's packages under its tag: false
+// when it waits for its floor (a package, design 51 *The floor*), and then nothing is claimed; the floor's wake looks at
+// the module again.
+func (b *Builder) number(ctx context.Context, module string, m delivery.Module, plan Plan, tag string) (versions.Numbering, bool) {
+	if b.Numbers == nil {
+		return versions.Numbering{}, true
+	}
+	var done map[string]string
+	if tag == "" {
+		done = b.doneDigests(ctx, module, m.FP2)
+	}
+	got, err := b.Numbers.Number(ctx, module, m, plan, tag, done)
+	for _, s := range got.Said {
+		b.logf("%s at %s: %s", module, m.FP2, s.Line)
+		// And in the build log (design 51 *The versions*: it says a version was kept, and why), between the build's start and end.
+		// A look at a key already done builds nothing and has no start or end: a version kept there says nothing new, and is
+		// not logged (each later look, a first view answered or a name heard, would add one).
+		if b.Log != nil && !(done != nil && s.Why == versions.SaidKept) {
+			b.Log(delivery.BuildLogEntry{Event: delivery.BuildSaidEvent, Module: module, FP: m.FP2, Commit: m.Commit, Node: b.Node,
+				At: time.Now().UTC(), Line: s.Line, Why: s.Why})
+		}
+	}
+	if err != nil {
+		// Said, and built as before: an unnumbered build is published by its digest (ADR 0617 §1), numbered at its next look.
+		b.logf("%s at %s: %v", module, m.FP2, fmt.Errorf("not numbered, the versions cannot be used: %w", err))
+		return versions.Numbering{}, true
+	}
+	if got.Wait != "" {
+		b.logf("%s at %s is not built yet: %s", module, m.FP2, got.Wait)
+		return got, false
+	}
+	return got, true
+}
+
+// doneDigests are the digests of a trunk build's key by artifact when the key is done, nil otherwise or when it cannot be
+// read: a look at a done build numbers what it left unnumbered with them (versions.BuildClaim.Done).
+func (b *Builder) doneDigests(ctx context.Context, module, fp string) map[string]string {
+	key, err := delivery.BuilderBuildKey(module, fp)
+	if err != nil || b.Claimer.Store == nil {
+		return nil
+	}
+	raw, _, found, err := b.Claimer.Store.Get(ctx, key)
+	if err != nil || !found {
+		return nil
+	}
+	cur, err := delivery.DecodeBuilderBuild(raw)
+	if err != nil || cur.State != delivery.BuildDone {
+		return nil
+	}
+	out := map[string]string{}
+	for _, a := range cur.Artifacts {
+		if a.Digest != "" {
+			out[a.Name] = a.Digest
+		}
+	}
+	return out
+}
+
+// PackageNamed looks at a module again when the indexer's packages state names a name for one of its packages
+// (versions.NamedModule): a done trunk build that left the package unnumbered, its name not known at its claim, is
+// numbered then with the done build's digests, and version.numbered says them for its build module's late publish.
+func (b *Builder) PackageNamed(ctx context.Context, module string) {
+	b.init()
+	b.mu.Lock()
+	m, ok := b.known[module]
+	b.mu.Unlock()
+	if ok {
+		b.consider(ctx, module, m)
+	}
+}

modules/mesh-delivery-builder/internal/build/plan.go

@@ -8,9 +8,9 @@ import (
 	"sort"
 	"strings"
 
+	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun"
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
 )
 
 // ImageBuildModule is the build module that builds an image artifact (novox/hq ADR 0487): buildah, rootless, on the nodes that

modules/mesh-delivery-builder/internal/build/plan_test.go

@@ -3,11 +3,12 @@ package build
 import (
 	"errors"
 
-	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
 	"strings"
 	"testing"
 
+	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun"
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 )
 

modules/mesh-delivery-builder/internal/build/r4e_test.go

@@ -305,10 +305,9 @@ func TestTheFetchOfAModuleNamingItsPathsCarriesItsDirectoryAndThosePaths(t *test
 	r := newRig(t, tsPackage)
 	r.bm.packages["lib"] = "@novox/mesh-sdk@0.1.15"
 	paths := map[string]string{"src": hex40('1'), "package.json": hex40('2')}
-	tree, err := delivery.NamedTree(manifestD, paths)
-	if err != nil {
-		t.Fatal(err)
-	}
+	// The named tree the indexer computes from those paths (its own, ADR 0593 §2), given as data: the builder reads it,
+	// never computes it.
+	const tree = delivery.NamedTreePrefix + "5b5e0f3b6f3c1f2a9d8e7c6b5a4938271605f4e3d2c1b0a9f8e7d6c5b4a39281"
 	data, err := delivery.EncodeModule(delivery.Module{Repository: "novox/mesh-sdk", Commit: "7a74cee83f88e6585a5511c3cc53bdf0f5303d20", FP2: fp1, Manifest: manifestD, Path: ".",
 		Toolchains: agreedToolchains, Inputs2: &delivery.KeptInputs2{Tree: tree, Paths: paths}})
 	if err != nil {

modules/mesh-delivery-builder/internal/build/round4_test.go

@@ -2,9 +2,10 @@ package build
 
 import (
 	"context"
-	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
 	"testing"
 
+	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun"
+
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
 )

modules/mesh-delivery-builder/internal/build/run.go

@@ -6,15 +6,20 @@ import (
 	"errors"
 	"fmt"
 	"maps"
+	"slices"
 	"sort"
+	"strconv"
 	"strings"
 	"sync"
 	"time"
 
+	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun"
+	"git.novox.be/novox/mesh-delivery/sdk/forms"
 	"git.novox.be/novox/mesh-sdk/go/buildstep"
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
+
+	"mesh-delivery-builder/internal/versions"
 )
 
 // ToolchainEntries are the nodes' toolchain entries of a language (buildrun.ToolchainSet).
@@ -50,7 +55,7 @@ type Builder struct {
 	// Answered is told the build module whose step answered a reference (issue 1886): what the builder says it writes
 	// rests on it. Nil tells nobody.
 	Answered func(buildModule string)
-	// Stored answers which references the artifact store no longer holds (the controller's verb held; issue 1937): a done
+	// Stored answers which references the artifact store no longer holds (the seat mesh-artifact-sweep's verb held; issue 1937): a done
 	// key of the trunk's fingerprint is asked before it is left done (ClaimOptions.Stored). Nil asks nothing.
 	Stored func(ctx context.Context, references []string) (gone []string, err error)
 	// Trunk answers the head of a repository in the gate's source revision rev (source.main at that revision): the trunk a
@@ -66,8 +71,27 @@ type Builder struct {
 	// Askings is how many times one build module's part of a build is asked, the first included, before its key is failed
 	// with why; DefaultAskings when 0.
 	Askings int
+	// DeclineBound and DeclinePause bound and pace the asks build nodes off the agreed toolchain declined (ADR 0584 clause 2):
+	// they are no askings. DefaultDeclineBound and DefaultDeclinePause when 0; a negative DeclinePause puts it again at once.
+	DeclineBound, DeclinePause time.Duration
 	// Said is told each ask asked again (the builder's event build.asked-again). Nil tells nobody.
 	Said func(AskedAgain)
+	// Log is told each build's start and end, the entries of the builder's log (novox/hq ADR 0571 §1). Nil tells nobody.
+	Log func(delivery.BuildLogEntry)
+	// Now is the builder's clock: of the log, and of the decline bound (DeclineBound runs from the first decline); nil is
+	// time.Now. Node is the node the builder runs on, which asked the build.
+	Now  func() time.Time
+	Node string
+	// Numbers numbers each trunk build at its claim and records what it was built with (design 51 *The versions*); nil
+	// numbers nothing.
+	Numbers Numbers
+	// Tags answers a check's build's tag from the kept tag asks; nil numbers no check's build.
+	Tags TagOf
+	// Forms answers what each node's engine states it reads (ADR 0618 §2, ADR 0624 §1): present, the nodes whose engine
+	// answered when last asked, and counted, every node the placement names, present or away, a node with no statement
+	// stating nothing (the baseline's first forms). A done key names each artifact in the forms these keep, the oldest in
+	// its single reference, and its needs. Nil: no node states anything, and the first forms are kept.
+	Forms func() (present, counted map[string][]string)
 
 	once     sync.Once
 	sem      chan struct{}
@@ -79,8 +103,10 @@ type Builder struct {
 	plans    map[string]planned            // by manifest digest
 	cands    map[string]delivery.Candidate // by candidates key (candidates.go)
 	via      map[string]via                // by build key: a candidate's fetch (candidates.go)
-	trunkFP  map[string]bool               // by build key: a trunk module value carries this fingerprint
-	tried    map[string]bool               // by build key: looked at since this process started
+	// outOfStep are, by build key, the out-of-step files a build's lanes answered, until its end entry takes them.
+	outOfStep map[string][]string
+	trunkFP   map[string]bool // by build key: a trunk module value carries this fingerprint
+	tried     map[string]bool // by build key: looked at since this process started
 	// published are the package versions `<name>@<version>` a done key of this bucket names as a package's reference: a key
 	// waiting for one is built once it is here (ADR 0500 clause 6).
 	published map[string]bool
@@ -251,8 +277,8 @@ func (b *Builder) storedOnce(key string) func(ctx context.Context, references []
 	}
 }
 
-// ArtifactsGone takes the controller's event artifacts-gone in (issue 1937): a take-in found that the store does not
-// hold what the module's key names. The module is looked at again, which asks the store (ClaimOptions.Stored) and
+// ArtifactsGone takes the seat mesh-artifact-sweep's event artifacts-gone in (issue 1937, ADR 0571 §2): the sweep found
+// that the store does not hold what the module's key names. The module is looked at again, which asks the store (ClaimOptions.Stored) and
 // builds the key again; an event for a fingerprint the module no longer has is said and left. The event only wakes the
 // builder: what is built rests on the store's answer, never on the event alone.
 func (b *Builder) ArtifactsGone(ctx context.Context, e delivery.ArtifactsGone) {
@@ -409,7 +435,7 @@ func (b *Builder) try(ctx context.Context, module string, m delivery.Module) {
 	if planErr == nil && !nothing {
 		if why := b.stale(m, plan); why != "" {
 			// The fingerprint names a toolchain the build nodes no longer agree on: a new fingerprint is coming, and a build
-			// now would be of this source with another toolchain (ADR 0477 clause 2). Nothing is written.
+			// now would be of this source with another toolchain (ADR 0584 clause 1, which changes ADR 0477 clause 2). Nothing is written.
 			b.logf("%s at %s is not built: %s", module, m.FP2, why)
 			return
 		}
@@ -419,6 +445,17 @@ func (b *Builder) try(ctx context.Context, module string, m delivery.Module) {
 	first := !b.tried[key]
 	b.tried[key] = true
 	b.mu.Unlock()
+	var numbering versions.Numbering
+	tag := ""
+	if !trunk && b.Tags != nil && b.refOf(module, m.FP2) != "" {
+		tag, _ = b.Tags(ctx, delivery.RepositoryName(m.Repository), m.Commit)
+	}
+	if (trunk || tag != "") && planErr == nil && !nothing {
+		var goOn bool
+		if numbering, goOn = b.number(ctx, module, m, plan, tag); !goOn {
+			return
+		}
+	}
 	cl, err := b.Claimer.Claim(ctx, module, m.FP2, m.Manifest, ClaimOptions{TakeOver: first, ImageBuilder: imageSeat, Trunk: trunk, Published: b.isPublished,
 		Stored: b.storedOnce(key)})
 	if err != nil {
@@ -429,6 +466,7 @@ func (b *Builder) try(ctx context.Context, module string, m delivery.Module) {
 		return
 	}
 	b.handClaimed(key, cl.Rev)
+	b.logBuild(LogStarted(module, m, b.refOf(module, m.FP2), b.Node, b.now()))
 	if cl.Unasked != nil {
 		b.logf("%v", cl.Unasked)
 	}
@@ -478,6 +516,14 @@ func (b *Builder) try(ctx context.Context, module string, m delivery.Module) {
 		b.logf("%s: the build could not be written: %v", cl.Key, err)
 		return
 	}
+	ended := LogEnded(module, m, b.refOf(module, m.FP2), b.Node, b.now(), result)
+	ended.OutOfStep = b.takeOutOfStep(key) // the generated files the build module's compare found out of step (design 26)
+	b.logBuild(ended)
+	if result.State == delivery.BuildDone && b.Numbers != nil && len(numbering.Versions) > 0 {
+		if err := b.Numbers.Built(ctx, module, m, plan, numbering, result.Artifacts); err != nil {
+			b.logf("%s: %v", cl.Key, err)
+		}
+	}
 	if result.State == delivery.BuildFailed {
 		b.logf("%s: failed: %s", cl.Key, result.Error)
 	}
@@ -498,10 +544,11 @@ func (b *Builder) stale(m delivery.Module, plan Plan) string {
 			continue // an archive is packed with no toolchain
 		}
 		language := buildrun.LanguageOf[bm]
-		tc, none := delivery.AgreedToolchain(b.Toolchains.Entries(language))
-		if none != "" {
-			return fmt.Sprintf("the %s toolchain is not agreed: %s", language, none)
+		ag := delivery.ToolchainAgreement(b.Toolchains.Entries(language))
+		if ag.Wait != "" {
+			return fmt.Sprintf("the %s toolchain is not agreed: %s", language, ag.Wait)
 		}
+		tc := ag.Toolchain
 		want, ok := m.Toolchains[language]
 		if !ok || want.Version != tc.Version || want.Recipe != tc.Recipe {
 			return fmt.Sprintf("the fingerprint names %s %s (recipe %s) and the nodes agree on %s (recipe %s)", language, want.Version, want.Recipe, tc.Version, tc.Recipe)
@@ -521,6 +568,8 @@ type lane struct {
 	toolchain    *delivery.ToolchainUsed
 	digests      map[string]string // artifact -> digest
 	references   map[string]string // artifact -> the reference an image was pushed to (a trunk build only)
+	imports      []string          // the mesh packages the lane's programs import, as its build module answered them
+	outOfStep    []string          // the generated files its build module's compare found out of step, passed or failed
 	err          error
 }
 
@@ -535,7 +584,8 @@ func (b *Builder) build(ctx context.Context, module string, m delivery.Module, p
 	repository := delivery.RepositoryName(m.Repository)
 	var lanes []*lane
 	used := map[string]delivery.ToolchainUsed{}
-	var kept []string // build modules whose artifacts stay as the prior done key has them
+	var sitting []string // the nodes that sit out of a language's build, said in the key's step (ADR 0584 clause 2)
+	var kept []string    // build modules whose artifacts stay as the prior done key has them
 	for _, bm := range plan.Modules() {
 		if prior != nil && len(only) > 0 && !only[bm] {
 			kept = append(kept, bm)
@@ -545,10 +595,12 @@ func (b *Builder) build(ctx context.Context, module string, m delivery.Module, p
 		if bm != ImageBuildModule && plan.NeedsToolchain(bm) {
 			// The ask names the toolchain the fingerprint was computed with; a node building with another refuses it.
 			language := buildrun.LanguageOf[bm]
-			tc, none := delivery.AgreedToolchain(b.Toolchains.Entries(language))
-			if none != "" {
-				return failed("the %s toolchain is not agreed: %s", language, none)
+			ag := delivery.ToolchainAgreement(b.Toolchains.Entries(language))
+			if ag.Wait != "" {
+				return failed("the %s toolchain is not agreed: %s", language, ag.Wait)
 			}
+			tc := ag.Toolchain
+			sitting = append(sitting, SittingOutWords(language, ag)...)
 			if want := m.Toolchains[language]; want.Version != tc.Version || want.Recipe != tc.Recipe {
 				return delivery.BuilderBuild{} // the agreed toolchain moved since try looked: nothing is written
 			}
@@ -573,6 +625,9 @@ func (b *Builder) build(ctx context.Context, module string, m delivery.Module, p
 		go func() { defer wg.Done(); b.runLane(ctx, l, repository, m, module, asked) }()
 	}
 	wg.Wait()
+	if key, err := delivery.BuilderBuildKey(module, m.FP2); err == nil {
+		b.keepOutOfStep(key, lanes)
+	}
 	var errs []string
 	for _, l := range lanes {
 		if l.err != nil {
@@ -588,6 +643,10 @@ func (b *Builder) build(ctx context.Context, module string, m delivery.Module, p
 		return failed("%s", keyError(errs))
 	}
 	var artifacts []delivery.BuiltArtifact
+	var present, counted map[string][]string
+	if b.Forms != nil {
+		present, counted = b.Forms()
+	}
 	keptModule := map[string]bool{}
 	for _, bm := range kept {
 		keptModule[bm] = true
@@ -616,6 +675,7 @@ func (b *Builder) build(ctx context.Context, module string, m delivery.Module, p
 			return failed("%s", err)
 		}
 		built := delivery.BuiltArtifact{Name: t.Artifact, Kind: t.Kind, Digest: d}
+		var answered []string
 		for _, l := range lanes {
 			if l.module != t.Module {
 				continue
@@ -627,10 +687,11 @@ func (b *Builder) build(ctx context.Context, module string, m delivery.Module, p
 				return failed("%s%s on %s: the build answered no reference, so its push to the artifact store was not answered", delivery.NotStored, t.Artifact, l.node)
 			}
 			if r != "" {
-				built.Reference = r
+				answered = append(answered, r)
 			}
 		}
-		artifacts = append(artifacts, built)
+		// The forms a counted node's engine reads are kept, the oldest in the single reference (ADR 0624 §1, §3).
+		artifacts = append(artifacts, forms.Current.Choose(built, answered, present, counted))
 	}
 	var steps []string
 	for _, l := range lanes {
@@ -645,10 +706,14 @@ func (b *Builder) build(ctx context.Context, module string, m delivery.Module, p
 		}
 	}
 	step := "built " + strings.Join(steps, "; ")
+	if len(sitting) > 0 {
+		step += " (" + strings.Join(sitting, "; ") + ")"
+	}
 	if len(used) == 0 {
 		used = nil
 	}
-	done := delivery.BuilderBuild{State: delivery.BuildDone, By: b.Claimer.By, Manifest: m.Manifest, Step: step, Artifacts: artifacts, Toolchains: used}
+	done := delivery.BuilderBuild{State: delivery.BuildDone, By: b.Claimer.By, Manifest: m.Manifest, Step: step, Artifacts: artifacts, Toolchains: used,
+		Imports: importsOf(lanes), Needs: forms.Current.Needs(artifacts)} // the forms it is written in (ADR 0618 §1)
 	if _, err := delivery.EncodeBuilderBuild(done); err != nil {
 		// A reference the build module answered that does not name the artifact and its digest is no reference.
 		return failed("%s%v", delivery.NotStored, err)
@@ -743,7 +808,7 @@ func (n *askNotes) note(ctx context.Context, language, id, step string) error {
 	n.mu.Lock()
 	defer n.mu.Unlock()
 	v := n.cl.Build
-	v.State, v.By, v.Step, v.Error, v.Artifacts = delivery.BuildBuilding, n.b.Claimer.By, step, "", nil
+	v.State, v.By, v.Step, v.Error, v.Artifacts, v.Needs = delivery.BuildBuilding, n.b.Claimer.By, step, "", nil, nil
 	v.Asks = maps.Clone(v.Asks)
 	if v.Asks == nil {
 		v.Asks = map[string]string{}
@@ -800,6 +865,11 @@ func (b *Builder) runLane(ctx context.Context, l *lane, repository string, m del
 		job.Fetch = req.Args()
 	}
 	ask := delivery.StepAsk{ID: buildstep.NewID(), Kind: kind, Language: language, Asker: delivery.BuilderModule, At: time.Now(), Build: job}
+	if language == delivery.AskGo && job.Fetch != nil && len(m.Packages) > 0 {
+		// The versions of the mesh packages the fingerprint was computed with (novox/hq ADR 0573 §2): the build module writes
+		// them into the workspace, whatever the repository's go.mod names.
+		ask.Packages = maps.Clone(m.Packages)
+	}
 	if id := asked.resume(language); id != "" {
 		ask.ID = id // put before this builder started again: the stream holds it, or a node already ran it
 		if b.Held != nil {
@@ -834,6 +904,12 @@ func (b *Builder) runLane(ctx context.Context, l *lane, repository string, m del
 		return
 	}
 	l.node = step.Node
+	// The build module's compare of a contracts module's generated files (design 26, CAT-BG5/BN2) answers the files out
+	// of step as delivery.BuildAnswer.OutOfStep, in a failed step's result too: read before the step's state is.
+	var compared delivery.BuildAnswer
+	if len(step.Result) > 0 && json.Unmarshal(step.Result, &compared) == nil {
+		l.outOfStep = compared.OutOfStep
+	}
 	if step.State != delivery.StepPassed {
 		l.err = fmt.Errorf("%s on %s: the ask %s %s: %s", l.module, step.Node, ask.ID, step.State, step.Reason)
 		return
@@ -843,6 +919,7 @@ func (b *Builder) runLane(ctx context.Context, l *lane, repository string, m del
 		l.err = fmt.Errorf("the ask of %s on %s answered what is not a build: %s", l.module, step.Node, step.Result)
 		return
 	}
+	l.imports = answer.Imports
 	built := map[string]delivery.AskBuilt{}
 	for _, a := range answer.Artifacts {
 		built[a.Artifact] = a
@@ -872,3 +949,117 @@ func needsFetch(tasks []Task) bool {
 	}
 	return false
 }
+
+func (b *Builder) now() time.Time {
+	if b.Now != nil {
+		return b.Now()
+	}
+	return time.Now()
+}
+
+// logBuild tells the log an entry, said in the journal when it cannot be one.
+func (b *Builder) logBuild(e delivery.BuildLogEntry) {
+	if b.Log == nil {
+		return
+	}
+	if _, err := delivery.EncodeBuildLogEntry(e); err != nil {
+		b.logf("%s at %s: no log entry: %v", e.Module, e.FP, err)
+		return
+	}
+	b.Log(e)
+}
+
+// refOf is the ref a candidate's build of module's fingerprint is built for, "" for the trunk's.
+func (b *Builder) refOf(module, fp string) string {
+	key, err := delivery.BuilderBuildKey(module, fp)
+	if err != nil {
+		return ""
+	}
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	return b.via[key].Ref
+}
+
+// LogStarted is the log's entry of a build of module's fingerprint starting (ADR 0571 §1): the module, the fingerprint, the
+// source revision, where it is built from (repository, directory, commit, the candidate's ref), the node of the builder
+// that asked it and the time.
+func LogStarted(module string, m delivery.Module, ref, by string, at time.Time) delivery.BuildLogEntry {
+	dir := m.Path
+	if dir == "" {
+		dir = delivery.RootPath
+	}
+	return delivery.BuildLogEntry{Event: delivery.BuildStartedEvent, Module: module, FP: m.FP2, Source: strconv.FormatUint(m.Src, 10),
+		Repository: m.Repository, Directory: dir, Commit: m.Commit, Ref: ref, Node: by, At: at.UTC()}
+}
+
+// LogEnded is the log's entry of that build ending: the outcome (done, failed or queued), the manifest built, the bases it
+// was built against and each artifact made, as the done key has them: what the operator's command nox builds shows of a build.
+func LogEnded(module string, m delivery.Module, ref, by string, at time.Time, result delivery.BuilderBuild) delivery.BuildLogEntry {
+	e := LogStarted(module, m, ref, by, at)
+	e.Event, e.Outcome, e.Manifest = delivery.BuildEndedEvent, result.State, m.Manifest
+	if result.Manifest != "" {
+		e.Manifest = result.Manifest
+	}
+	if m.Inputs2 != nil {
+		e.Against = append([]string(nil), m.Inputs2.Bases...)
+	}
+	e.Made = append([]delivery.BuiltArtifact(nil), result.Artifacts...)
+	e.Imports = append([]string(nil), result.Imports...) // the indexer keeps them on the module (novox/hq ADR 0593 §2)
+	return e
+}
+
+// keepOutOfStep holds, by build key, the out-of-step files the lanes' build modules answered, sorted and each once, until
+// the build's end entry takes them (takeOutOfStep); a build with none holds nothing.
+func (b *Builder) keepOutOfStep(key string, lanes []*lane) {
+	seen := map[string]bool{}
+	for _, l := range lanes {
+		for _, f := range l.outOfStep {
+			seen[f] = true
+		}
+	}
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	if len(seen) == 0 {
+		delete(b.outOfStep, key)
+		return
+	}
+	if b.outOfStep == nil {
+		b.outOfStep = map[string][]string{}
+	}
+	b.outOfStep[key] = slices.Sorted(maps.Keys(seen))
+}
+
+// takeOutOfStep answers the out-of-step files held for a build key and forgets them.
+func (b *Builder) takeOutOfStep(key string) []string {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	files := b.outOfStep[key]
+	delete(b.outOfStep, key)
+	return files
+}
+
+// importsOf are the mesh packages the lanes' programs import, as their build modules answered them (novox/hq ADR 0593
+// §2): sorted and each once; nil when none answered any. A lane kept from a prior build answered none, so a build that
+// kept one reports only what it built.
+func importsOf(lanes []*lane) []string {
+	seen := map[string]bool{}
+	for _, l := range lanes {
+		for _, p := range l.imports {
+			seen[p] = true
+		}
+	}
+	if len(seen) == 0 {
+		return nil
+	}
+	return slices.Sorted(maps.Keys(seen))
+}
+
+// SittingOutWords says, per node that is not on the agreed toolchain of a language, that it sits out and which version
+// it has against the agreed one: "ace sits out: typescript 26.12.1, agreed 26.13.0" (novox/hq ADR 0584 clause 2).
+func SittingOutWords(language string, a delivery.Agreement) []string {
+	var out []string
+	for _, s := range a.SittingOut {
+		out = append(out, fmt.Sprintf("%s sits out: %s %s, agreed %s", s.Node, language, s.Version, a.Toolchain.Version))
+	}
+	return out
+}

modules/mesh-delivery-builder/internal/build/run_test.go

@@ -5,7 +5,8 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
+	"reflect"
+	"slices"
 	"strconv"
 	"strings"
 	"sync"
@@ -13,9 +14,13 @@ import (
 	"testing"
 	"time"
 
-	"git.novox.be/novox/mesh-sdk/go/buildstep"
+	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/buildrun"
+	"git.novox.be/novox/mesh-delivery/sdk/forms"
+	stdio "git.novox.be/novox/mesh-sdk/go"
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
+
+	"mesh-delivery-builder/internal/versions"
 )
 
 // buildModules simulates the two build modules on the nodes: a long tool answers a step and key at once and writes the
@@ -138,7 +143,7 @@ type rig struct {
 // toolPrefix is the start of each build module's tool names, as the fake build modules answer them.
 var toolPrefix = map[string]string{buildrun.GoBuildModule: "build_go_", buildrun.NodeBuildModule: "build_node_", ImageBuildModule: "build_image_"}
 
-// answer runs an ask as the build module that pulls it does (buildstep.RunAsk), with the fake build modules' tools on the
+// answer runs an ask as the build module that pulls it does (runAsk), with the fake build modules' tools on the
 // rig's pulling node, and answers the step that node writes.
 func (r *rig) answer(a delivery.StepAsk) delivery.Step {
 	node := r.puller
@@ -147,7 +152,7 @@ func (r *rig) answer(a delivery.StepAsk) delivery.Step {
 	}
 	module, _ := delivery.BuildModuleOf(a.Language)
 	runner := buildrun.Runner{Caller: r.bm, Steps: r.bm.steps, Bound: time.Second}
-	tool := func(name string) buildstep.StepFunc {
+	tool := func(name string) stepFunc {
 		return func(ctx context.Context, args map[string]any) (any, error) {
 			raw, err := runner.Run(ctx, module, node, toolPrefix[module]+name, args)
 			if err != nil {
@@ -156,8 +161,8 @@ func (r *rig) answer(a delivery.StepAsk) delivery.Step {
 			return raw, nil
 		}
 	}
-	steps := buildstep.AskSteps{Fetch: tool("fetch"), Build: tool("build"), Copy: tool("copy")}
-	out, err := buildstep.RunAsk(context.Background(), steps, a)
+	steps := askSteps{Fetch: tool("fetch"), Build: tool("build"), Copy: tool("copy")}
+	out, err := runAsk(context.Background(), steps, a)
 	step := delivery.Step{ID: a.ID, Tool: a.Kind + " ask", Node: node, State: delivery.StepPassed}
 	if err != nil {
 		step.State, step.Reason = delivery.StepFailed, err.Error()
@@ -220,8 +225,54 @@ var (
 )
 
 func TestABundleAndAnArchiveAreBuiltOnOneNodeAndDone(t *testing.T) { // 1607/AC7, ADR 0478 clauses 1, 4
+	t.Run("the imports a build answers reach the done key and the log", importsABuildAnswersReachTheDoneKeyAndTheLog)
+	t.Run("the out-of-step files a build answers reach the log", outOfStepFilesABuildAnswersReachTheLog)
+	t.Run("ADR 0624: a done key keeps each form a counted node reads", aDoneKeyKeepsEachFormACountedNodeReads)
 	r := newRig(t, goBundle, archiveA, tsBundle)
+	// ADR 0584: a third node agrees with novox and ace's typescript is the odd one; the build is done and its step says ace sits out.
+	r.tools.Put(buildrun.NodeBuildModule, "g14.typescript", tcValue(t, "typescript", "tsc5"), false)
+	r.tools.Put(buildrun.NodeBuildModule, "ace.typescript", tcValue(t, "typescript", "tsc4"), false)
+	defer func() {
+		if st := r.st.vals[r.key]; !strings.Contains(string(st), "ace sits out: typescript tsc4, agreed tsc5") {
+			t.Errorf("the key does not say ace sits out: %s", st)
+		}
+	}()
+	var logged []delivery.BuildLogEntry
+	var lmu sync.Mutex
+	r.b.Node, r.b.Log = "novox", func(e delivery.BuildLogEntry) { lmu.Lock(); logged = append(logged, e); lmu.Unlock() }
 	v := r.consider(t, "modules/m")
+	// 1955/L7 (ADR 0571 §1): the build is one start and one end in the builder's log, every field named, its duration read
+	// from the two.
+	if len(logged) != 2 || logged[0].Event != delivery.BuildStartedEvent || logged[1].Event != delivery.BuildEndedEvent ||
+		logged[1].Outcome != delivery.BuildDone || len(logged[1].Made) != 3 || logged[1].Made[0].Reference == "" ||
+		logged[1].Manifest != manifestD || logged[0].Manifest != "" || logged[0].Repository != "novox/mesh-catalog" ||
+		logged[0].Directory != "modules/m" || logged[0].Commit != "7a74cee83f88e6585a5511c3cc53bdf0f5303d20" || logged[0].Node != "novox" ||
+		logged[0].FP != fp1 || logged[0].Module != "m" {
+		t.Fatalf("logged = %+v", logged)
+	}
+	for _, e := range logged {
+		if _, err := delivery.EncodeBuildLogEntry(e); err != nil {
+			t.Errorf("an entry the log refuses: %v", err)
+		}
+	}
+	if _, ok := delivery.BuildDuration(logged[0], logged[1]); !ok {
+		t.Error("no duration from the two entries")
+	}
+	// builder_builds_since (ADR 0571 clause 9) answers the end alone from the log's page, and says when the log holds more.
+	var page stdio.LogPage
+	for i, e := range logged {
+		raw, _ := delivery.EncodeBuildLogEntry(e)
+		page.Entries = append(page.Entries, stdio.LogEntry{Sequence: uint64(i + 1), Key: e.Module, Value: raw, At: e.At})
+	}
+	page.Next = 3
+	since, err := BuildsSince(func(time.Time, string, int) (*stdio.LogPage, error) { return &page, nil }, logged[0].At)
+	if err != nil || len(since.Builds) != 1 || since.Builds[0].Event != delivery.BuildEndedEvent || len(since.Builds[0].Made) != 3 || !since.More {
+		t.Errorf("builds since = %+v, %v, want the one end and more", since, err)
+	}
+	page.Entries[0].Value = []byte(`{"v":0}`)
+	if _, err := BuildsSince(func(time.Time, string, int) (*stdio.LogPage, error) { return &page, nil }, logged[0].At); err == nil {
+		t.Error("an entry that does not read was skipped, want it refused")
+	}
 	if v.State != delivery.BuildDone || v.By != "novox.builder" || v.Manifest != manifestD || len(v.Artifacts) != 3 {
 		t.Fatalf("build = %+v, want done by novox.builder with three artifacts", v)
 	}
@@ -233,6 +284,11 @@ func TestABundleAndAnArchiveAreBuiltOnOneNodeAndDone(t *testing.T) { // 1607/AC7
 	if v.Artifacts[0].Kind != "archive" || v.Artifacts[1].Kind != "bundle" {
 		t.Errorf("kinds = %+v", v.Artifacts)
 	}
+	// ADR 0618 §1: the done key names the forms its references are written in, here the first form alone, and keeps no list
+	// beside the single reference while no counted node needs another form.
+	if !slices.Equal(v.Needs, []string{"form:artifact-store"}) || v.Artifacts[0].References != nil {
+		t.Errorf("needs = %v, references = %v", v.Needs, v.Artifacts[0].References)
+	}
 	if got := v.Toolchains["go"]; got.Version != "go1.27.1" || got.Recipe != "1" {
 		t.Errorf("toolchains = %+v, want go and typescript named", v.Toolchains)
 	}
@@ -264,9 +320,16 @@ func TestABundleAndAnArchiveAreBuiltOnOneNodeAndDone(t *testing.T) { // 1607/AC7
 func TestATrunkFingerprintIsOneAskOnTheDeliveryStream(t *testing.T) {
 	r := newRig(t, goBundle)
 	r.asks.Answer = nil // no node has pulled it yet
-	r.b.Module(context.Background(), "m", moduleValue(t, "modules/m"))
+	// Issue 1585 (ADR 0573 §2): the ask carries the package versions the fingerprint was computed with.
+	sdk := delivery.PackageVersions{"git.novox.be/novox/mesh-sdk/go": hex40('5')}
+	data, err := delivery.EncodeModule(delivery.Module{Repository: "novox/mesh-catalog", Commit: "7a74cee83f88e6585a5511c3cc53bdf0f5303d20",
+		FP2: fp1, Manifest: mdigest('a'), Path: "modules/m", Toolchains: agreedToolchains, Packages: sdk})
+	if err != nil {
+		t.Fatal(err)
+	}
+	r.b.Module(context.Background(), "m", data)
 	var asks []delivery.StepAsk
-	for deadline := time.Now().Add(2 * time.Second); len(asks) == 0; time.Sleep(time.Millisecond) {
+	for deadline := time.Now().Add(10 * time.Second); len(asks) == 0; time.Sleep(time.Millisecond) {
 		if time.Now().After(deadline) {
 			t.Fatal("no ask was put")
 		}
@@ -276,6 +339,9 @@ func TestATrunkFingerprintIsOneAskOnTheDeliveryStream(t *testing.T) {
 	if len(asks) != 1 || a.Kind != delivery.AskDelivery || a.Language != delivery.AskGo || a.Build == nil || a.Build.FP != fp1 {
 		t.Fatalf("asks = %+v, want one Go delivery ask of the fingerprint", asks)
 	}
+	if !reflect.DeepEqual(a.Packages, sdk) {
+		t.Errorf("the ask's packages = %v, want %v", a.Packages, sdk)
+	}
 	if v := valueOf(t, r.st, r.key); v.State != delivery.BuildBuilding || v.Asks[delivery.AskGo] != a.ID {
 		t.Fatalf("the key = %+v, want building naming the ask %s", v, a.ID)
 	}
@@ -363,8 +429,19 @@ func TestACandidatesImageCallCarriesNoPublishAndItsKeyNoReference(t *testing.T)
 	r := newRig(t, imageArt)
 	r.puller = "ace"
 	trunkModule(t, r)
+	// DLV-B6: a check's build of a head a kept tag ask names is numbered under that tag at its claim.
+	nums := &fakeNumbers{}
+	var tagAsked []string
+	r.b.Numbers = nums
+	r.b.Tags = func(_ context.Context, repository, head string) (string, bool) {
+		tagAsked = append(tagAsked, repository+"@"+head)
+		return "feat-x", head == headX
+	}
 	r.b.Candidate(context.Background(), "feat%2Fx", candidateValue(t, "feat/x", 7, headX))
 	r.b.Wait()
+	if !slices.Equal(nums.tags, []string{"feat-x"}) || len(tagAsked) != 1 || !strings.HasSuffix(tagAsked[0], "@"+headX) {
+		t.Errorf("the check's build numbered with tags %v (asked %v), want feat-x for its head", nums.tags, tagAsked)
+	}
 	v := valueOf(t, r.st, r.key)
 	if v.State != delivery.BuildDone || len(v.Artifacts) != 1 || v.Artifacts[0].Reference != "" {
 		t.Fatalf("build = %+v, want done with no reference", v)
@@ -378,14 +455,69 @@ func TestACandidatesImageCallCarriesNoPublishAndItsKeyNoReference(t *testing.T)
 	}
 }
 
-func TestATrunkImageCallCarriesPublish(t *testing.T) { // 1705b
+func TestATrunkImageCallCarriesPublish(t *testing.T) { // 1705b; design 51 *The versions*: numbered at the claim
 	r := newRig(t, imageArt)
 	r.puller = "ace"
+	nums := &fakeNumbers{wait: "m/img: the package waits for its floor"}
+	r.b.Numbers = nums
+	r.b.Module(context.Background(), "m", moduleValue(t, "modules/m"))
+	r.b.Wait()
+	if _, ok := r.st.vals[r.key]; ok || nums.numbered != 1 {
+		t.Fatalf("a build waiting for its floor was claimed (numbered %d times)", nums.numbered)
+	}
+	nums.wait, nums.versions = "", map[string]string{"img": "0.1.4"}
 	r.consider(t, "modules/m")
 	calls := r.bm.callsOf("build_image_build")
 	if len(calls) != 1 || calls[0].body.(map[string]any)["publish"] != true {
 		t.Errorf("calls = %+v, want publish true", calls)
 	}
+	if nums.built["img"] != digest {
+		t.Errorf("the built digest recorded = %v, want %s for img", nums.built, digest)
+	}
+	if nums.done != nil {
+		t.Errorf("a build still to make was numbered with done digests %v", nums.done)
+	}
+	// The indexer's packages state names a package of the module (PackageNamed): the done build is looked at again and
+	// numbered with its key's digests, so version.numbered carries them for the late publish; nothing is built again.
+	looks := nums.numbered
+	r.b.PackageNamed(context.Background(), "m")
+	r.b.Wait()
+	if nums.numbered != looks+1 || nums.done["img"] != digest || len(r.bm.callsOf("build_image_build")) != 1 {
+		t.Errorf("a named package's done build: numbered %d more times with %v, %d image builds; want once with img %s and no build",
+			nums.numbered-looks, nums.done, len(r.bm.callsOf("build_image_build")), digest)
+	}
+	r.b.PackageNamed(context.Background(), "other")
+	r.b.Wait()
+	if nums.numbered != looks+1 {
+		t.Errorf("a module the builder does not know was looked at")
+	}
+}
+
+// fakeNumbers is Numbers that answers what it is set to and keeps the digests a done build recorded.
+type fakeNumbers struct {
+	wait     string
+	versions map[string]string
+	numbered int
+	built    map[string]string
+	tags     []string
+	done     map[string]string // the done key's digests the last look numbered with
+}
+
+func (f *fakeNumbers) Number(_ context.Context, _ string, _ delivery.Module, _ Plan, tag string, done map[string]string) (versions.Numbering, error) {
+	f.tags = append(f.tags, tag)
+	f.done = done
+	f.numbered++
+	return versions.Numbering{Wait: f.wait, Versions: f.versions}, nil
+}
+
+func (f *fakeNumbers) Built(_ context.Context, _ string, _ delivery.Module, _ Plan, got versions.Numbering, made []delivery.BuiltArtifact) error {
+	f.built = map[string]string{}
+	for _, a := range made {
+		if got.Versions[a.Name] != "" {
+			f.built[a.Name] = a.Digest
+		}
+	}
+	return nil
 }
 
 func TestAnUnpinnedUpstreamFailsNotPinnedAndIsNeverBuiltAgain(t *testing.T) { // B3, ADR 0498 clause 4
@@ -510,6 +642,7 @@ func TestAKeyIsBuiltOnlyWithTheToolchainItsFingerprintNamesAndNothingIsWrittenOt
 	r.b.Module(context.Background(), "m", moduleValueWith(t, "modules/m", old))
 	r.b.Wait()
 	if len(r.st.vals) != 0 || len(r.bm.calls) != 0 {
+		t.Run("a recipe that moves builds the module again under its new fingerprint", aRecipeThatMovesBuildsTheModuleAgainUnderItsNewFingerprint)
 		t.Errorf("keys %v and %d calls for a fingerprint of go1.26.0 while the nodes agree on go1.27.1, want neither", r.st.vals, len(r.bm.calls))
 	}
 	// A recipe that differs is a different toolchain too, and a value that names none (written before) is not built.
@@ -534,6 +667,45 @@ func TestAKeyIsBuiltOnlyWithTheToolchainItsFingerprintNamesAndNothingIsWrittenOt
 	}
 }
 
+// ADR 0603 §3 (D9): a source revision changing the Go build module's recipe and a Go module builds the module at once with
+// the recipe the nodes run and again, a second key under the new fingerprint, once the agreement moves to the new recipe;
+// the first key is neither rebuilt nor waited on.
+func aRecipeThatMovesBuildsTheModuleAgainUnderItsNewFingerprint(t *testing.T) {
+	r := newRig(t, goBundle)
+	r.consider(t, "modules/m")
+	calls := len(r.bm.calls)
+	fp2 := "src2:" + hex64('2')
+	for _, n := range []string{"ace", "novox"} {
+		b, err := delivery.EncodeToolchain(delivery.Toolchain{Language: "go", Version: "go1.27.1", Recipe: "2", At: time.Now()})
+		if err != nil {
+			t.Fatal(err)
+		}
+		r.tools.Put(buildrun.GoBuildModule, n+".go", b, false)
+	}
+	r.b.Reconsider(context.Background())
+	r.b.Wait()
+	if len(r.bm.calls) != calls {
+		t.Errorf("%d calls, was %d: the first fingerprint was built again for the new recipe", len(r.bm.calls), calls)
+	}
+	data, err := delivery.EncodeModule(delivery.Module{Repository: "novox/mesh-catalog", Commit: "7a74cee83f88e6585a5511c3cc53bdf0f5303d20", FP: "src1:" + hex64('f'), FP2: fp2,
+		Manifest: mdigest('a'), Path: "modules/m", Toolchains: map[string]delivery.ToolchainUsed{"go": {Version: "go1.27.1", Recipe: "2"}}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	r.b.Module(context.Background(), "m", data)
+	r.b.Wait()
+	second, err := delivery.BuilderBuildKey("m", fp2)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if v := valueOf(t, r.st, second); v.State != delivery.BuildDone || v.Toolchains["go"].Recipe != "2" {
+		t.Errorf("second build = %+v, want done with recipe 2", v)
+	}
+	if v := valueOf(t, r.st, r.key); v.State != delivery.BuildDone {
+		t.Errorf("first build = %+v, want it left done", v)
+	}
+}
+
 func TestNodesTheyDisagreeOnLeaveTheKeyUnwritten(t *testing.T) { // 1615/AC4
 	r := newRig(t, goBundle)
 	r.tools.Put(buildrun.GoBuildModule, "ace.go", tcValue(t, "go", "go1.26.0"), false)
@@ -650,7 +822,7 @@ func (g *goneAsks) asked() int {
 // waitForAsks waits until n asks were put.
 func waitForAsks(t *testing.T, r *rig, n int) []delivery.StepAsk {
 	t.Helper()
-	for deadline := time.Now().Add(2 * time.Second); len(r.asks.Asks()) < n; time.Sleep(time.Millisecond) {
+	for deadline := time.Now().Add(10 * time.Second); len(r.asks.Asks()) < n; time.Sleep(time.Millisecond) {
 		if time.Now().After(deadline) {
 			t.Fatalf("%d asks put, want %d", len(r.asks.Asks()), n)
 		}
@@ -670,7 +842,13 @@ func TestABuildAskWaitingInItsStreamIsNotBounded(t *testing.T) {
 		r.b.Gone, r.b.CheckAfter = gone, 5*time.Millisecond
 		r.b.Module(context.Background(), "m", moduleValue(t, "modules/m"))
 		waitForAsks(t, r, 1)
-		time.Sleep(100 * time.Millisecond)
+		// Five check bounds passed (five reads of whether it can be answered), so the ask waited past the step bound: an event
+		// to wait on, where a pause of 100 ms said nothing on a loaded machine.
+		for deadline := time.Now().Add(10 * time.Second); gone.asked() < 5; time.Sleep(time.Millisecond) {
+			if time.Now().After(deadline) {
+				t.Fatalf("whether the ask can still be answered was read %d times within 10 s, want 5", gone.asked())
+			}
+		}
 		if v := valueOf(t, r.st, r.key); v.State != delivery.BuildBuilding {
 			t.Fatalf("the key = %+v while its ask waits, want building", v)
 		}
@@ -683,6 +861,30 @@ func TestABuildAskWaitingInItsStreamIsNotBounded(t *testing.T) {
 			t.Fatalf("the key = %+v after %d asks, want done from the one ask", v, len(r.asks.Asks()))
 		}
 	})
+	t.Run("declined by a node off the agreed toolchain: put again, no asking used, the bound ends it loudly", func(t *testing.T) { // ADR 0584 clause 2
+		r := newRig(t, goBundle)
+		r.asks.Answer = nil
+		// The builder's clock steps a second at each read, so the bound of a minute ends the declines after many asks however
+		// slow the machine (a bound of 150 ms of wall clock let a loaded one put fewer than DefaultAskings).
+		var clock atomic.Int64
+		start := time.Now()
+		r.b.Now = func() time.Time { return start.Add(time.Duration(clock.Add(1)) * time.Second) }
+		r.b.DeclinePause, r.b.DeclineBound = -1, time.Minute
+		r.b.Module(context.Background(), "m", moduleValue(t, "modules/m"))
+		declined, _ := json.Marshal(delivery.StepDeclined{Declined: true, Lacks: []string{"the agreed toolchain go1.27.1 (recipe 1)"}})
+		waitForAsks(t, r, 1)
+		for ended, deadline := 0, time.Now().Add(20*time.Second); valueOf(t, r.st, r.key).State == delivery.BuildBuilding && time.Now().Before(deadline); time.Sleep(5 * time.Millisecond) {
+			if asks := r.asks.Asks(); len(asks) > ended { // each ask put again is declined in its turn
+				r.asks.End(delivery.Step{ID: asks[ended].ID, Node: "ace", State: delivery.StepRefused, Reason: "this node builds with go1.26.0", Result: declined})
+				ended++
+			}
+		}
+		r.b.Wait()
+		v := valueOf(t, r.st, r.key)
+		if n := len(r.asks.Asks()); v.State != delivery.BuildFailed || n <= DefaultAskings || !strings.Contains(v.Error, "declined for") || !strings.Contains(v.Error, "ace: this node builds with go1.26.0") {
+			t.Fatalf("the key = %+v after %d asks, want it failed after more than %d asks, naming ace and its reason", v, n, DefaultAskings)
+		}
+	})
 	for _, c := range []struct {
 		name    string
 		askings int
@@ -852,7 +1054,7 @@ func TestABuildAskWaitingInItsStreamIsNotBounded(t *testing.T) {
 			}
 			if c.byHand {
 				waitForAsks(t, r, 1)
-				for deadline := time.Now().Add(2 * time.Second); len(r.b.AskAgain(r.key, "stuck since 19:06")) == 0; time.Sleep(time.Millisecond) {
+				for deadline := time.Now().Add(10 * time.Second); len(r.b.AskAgain(r.key, "stuck since 19:06")) == 0; time.Sleep(time.Millisecond) {
 					if time.Now().After(deadline) {
 						t.Fatal("no lane of the key waits")
 					}
@@ -860,7 +1062,7 @@ func TestABuildAskWaitingInItsStreamIsNotBounded(t *testing.T) {
 			}
 			if c.deaf {
 				r.asks.End(r.answer(waitForAsks(t, r, 1)[0]))
-				for deadline := time.Now().Add(2 * time.Second); heard.Waiting() == 0; time.Sleep(time.Millisecond) {
+				for deadline := time.Now().Add(10 * time.Second); heard.Waiting() == 0; time.Sleep(time.Millisecond) {
 					if time.Now().After(deadline) {
 						t.Fatal("no ask is waited on")
 					}
@@ -1109,3 +1311,117 @@ type silentWatch struct{}
 func (silentWatch) WatchAsk(context.Context, string, string) (<-chan delivery.Step, error) {
 	return make(chan delivery.Step), nil
 }
+
+// aDoneKeyKeepsEachFormACountedNodeReads holds the builder's rows of ADR 0624's check: every build keeps each form a
+// counted node's engine reads, present or away, a node stating nothing reading the baseline's first form; the oldest kept
+// form is the single reference; a retired node leaves the count. old is the first form, new a fixture second form read
+// only by an engine stating form:new.
+func aDoneKeyKeepsEachFormACountedNodeReads(t *testing.T) {
+	fs := forms.ArtifactForms{
+		{Name: "old", First: true, Kinds: []string{"bundle"}, Is: func(r string) bool { return strings.HasPrefix(r, "artifact-store://") }},
+		{Name: "new", Kinds: []string{"bundle"}, Is: func(r string) bool { return strings.HasPrefix(r, "10.0.0.1:5000/") }},
+	}
+	both, nothing, onlyNew := []string{"form:new", "word:module"}, []string(nil), []string{"form:new"}
+	oldRef, newRef := "artifact-store://m/code/blobs/"+digest, "10.0.0.1:5000/m/code@"+digest
+	for _, row := range []struct {
+		name             string
+		present, counted map[string][]string
+		kept             []string
+		reference        string
+		references       []string
+	}{
+		{"A present {old,new}, B away {old}: both forms, the old in the single reference",
+			map[string][]string{"a": both}, map[string][]string{"a": both, "b": {"word:module"}}, []string{"old", "new"}, oldRef, []string{oldRef, newRef}},
+		{"A present {new}, B away stating nothing: the baseline's form stays",
+			map[string][]string{"a": onlyNew}, map[string][]string{"a": onlyNew, "b": nothing}, []string{"old", "new"}, oldRef, []string{oldRef, newRef}},
+		{"A present {old,new}, B away and never asked (no key): the baseline's form stays",
+			map[string][]string{"a": both}, map[string][]string{"a": both, "b": nil}, []string{"old", "new"}, oldRef, []string{oldRef, newRef}},
+		{"B retired: the new form only", map[string][]string{"a": both}, map[string][]string{"a": both}, []string{"new"}, newRef, nil},
+		{"B present stating nothing: the new form is not written",
+			map[string][]string{"a": both, "b": nothing}, map[string][]string{"a": both, "b": nothing}, []string{"old"}, oldRef, nil},
+		{"no node present: the first form", nil, map[string][]string{"a": both}, []string{"old"}, oldRef, nil},
+	} {
+		if got := fs.Kept("bundle", row.present, row.counted); !slices.Equal(got, row.kept) {
+			t.Errorf("%s: kept %v, want %v", row.name, got, row.kept)
+		}
+		a := fs.Choose(delivery.BuiltArtifact{Name: "code", Kind: "bundle", Digest: digest}, []string{newRef, oldRef}, row.present, row.counted)
+		if a.Reference != row.reference || !slices.Equal(a.References, row.references) {
+			t.Errorf("%s: %q %v, want %q %v", row.name, a.Reference, a.References, row.reference, row.references)
+		}
+		// An engine that predates the list reads the single reference, in a form every counted node reads (ADR 0624 §3).
+		if form, _ := fs.FormOf("bundle", a.Reference); form != row.kept[0] {
+			t.Errorf("%s: the single reference is in %q, want the oldest kept %q", row.name, form, row.kept[0])
+		}
+	}
+	// An answered reference no kept form names still names where the artifact is (ADR 0498 clause 1).
+	if a := fs.Choose(delivery.BuiltArtifact{Name: "code", Kind: "bundle", Digest: digest}, []string{oldRef}, map[string][]string{"a": both},
+		map[string][]string{"a": both}); a.Reference != oldRef {
+		t.Errorf("a lone answered reference was dropped: %+v", a)
+	}
+	withBoth := []delivery.BuiltArtifact{{Name: "code", Kind: "bundle", Digest: digest, Reference: oldRef, References: []string{oldRef, newRef}}}
+	if got := fs.Needs(withBoth); !slices.Equal(got, []string{"form:new", "form:old"}) {
+		t.Errorf("needs %v", got)
+	}
+	// The builder's own forms (forms.Current): a bundle a build step answers in the registry seat's form (mesh-build-go's
+	// oci-artifact-registry/<module>/<artifact>@<digest>) keeps the artifact-store form it derives for each counted node
+	// whose engine does not state form:seat-reference, that one in the single reference (ADR 0624 §1, §3).
+	seat := []string{forms.FormNeed(forms.FormSeatReference), "word:module"}
+	// Each kind the seat form names (a bundle through oci-artifact-registry, an image and an upstream copy through
+	// container-image-registry, the copy under the holder's own upstream/<host>/<path>), with the artifact-store form it derives.
+	for _, k := range []struct{ kind, seatRef, storeRef string }{
+		{"bundle", "oci-artifact-registry/m/code@" + digest, "artifact-store://m/code/blobs/" + digest},
+		{"image", "container-image-registry/m/code@" + digest, "artifact-store://m/code@" + digest},
+		{"upstream", "container-image-registry/upstream/quay.io:443/org/app@" + digest, "artifact-store://upstream/quay.io:443/org/app@" + digest},
+	} {
+		seatRef, storeRef := k.seatRef, k.storeRef
+		for _, row := range []struct {
+			name             string
+			present, counted map[string][]string
+			reference        string
+			references       []string
+			needs            []string
+		}{
+			{"seat form answered, B away stating nothing: the derived store form stays, in the single reference",
+				map[string][]string{"a": seat}, map[string][]string{"a": seat, "b": nil}, storeRef, []string{storeRef, seatRef},
+				[]string{"form:artifact-store", "form:seat-reference"}},
+			{"seat form answered, every counted engine reads it: the seat form only",
+				map[string][]string{"a": seat}, map[string][]string{"a": seat, "b": seat}, seatRef, nil, []string{"form:seat-reference"}},
+			{"seat form answered, a present engine stating nothing: the store form only",
+				map[string][]string{"a": seat, "b": nil}, map[string][]string{"a": seat, "b": nil}, storeRef, nil, []string{"form:artifact-store"}},
+			{"seat form answered, no node present: the store form", nil, map[string][]string{"a": seat}, storeRef, nil, []string{"form:artifact-store"}},
+		} {
+			a := forms.Current.Choose(delivery.BuiltArtifact{Name: "code", Kind: k.kind, Digest: digest}, []string{seatRef}, row.present, row.counted)
+			if a.Reference != row.reference || !slices.Equal(a.References, row.references) {
+				t.Errorf("%s %s: %q %v, want %q %v", k.kind, row.name, a.Reference, a.References, row.reference, row.references)
+			}
+			needs := forms.Current.Needs([]delivery.BuiltArtifact{a})
+			if !slices.Equal(needs, row.needs) {
+				t.Errorf("%s %s: needs %v, want %v", k.kind, row.name, needs, row.needs)
+			}
+			for node, stated := range row.counted {
+				if forms.Current.Held(needs, stated) {
+					t.Errorf("%s %s: the want of %s is held", k.kind, row.name, node)
+				}
+			}
+			if _, err := delivery.EncodeBuilderBuild(delivery.BuilderBuild{State: delivery.BuildDone, Manifest: strings.TrimPrefix(digest, "sha256:"), Artifacts: []delivery.BuiltArtifact{a}, Needs: needs}); err != nil {
+				t.Errorf("%s %s: %v", k.kind, row.name, err)
+			}
+		}
+	}
+	// What the assigner holds a want by (ADR 0624 §2), from the same forms.
+	for _, row := range []struct {
+		name   string
+		needs  []string
+		stated []string
+		held   bool
+	}{
+		{"a node stating {old}, a build carrying {old,new}: moves", []string{"form:new", "form:old"}, []string{"word:module"}, false},
+		{"a node stating nothing, a build carrying the baseline's form: moves", []string{"form:old"}, nil, false},
+		{"a build carrying {new} only, the node stating {old}: held", []string{"form:new"}, []string{"word:module"}, true},
+		{"a build naming no form: moves", nil, nil, false},
+	} {
+		if got := fs.Held(row.needs, row.stated); got != row.held {
+			t.Errorf("%s: held %v", row.name, got)
+		}
+	}
+}