Store optional requirements beside a plain requires list (hq issue 166, review of #281)

A controller older than optional requirements reads `requires` as names, and Inventory.Catalogue
stops at the first manifest it cannot read: the long form stored inside `requires` would have left
a rollback below this controller composing no machine. Stored, `requires` stays plain and the
optional names sit in `optional-requires`, a key an older controller sets aside, leaving out only
the module carrying it. A refusal of a hard requirement now names a module that wants it hard.

.gitignore

@@ -6,3 +6,5 @@
 /mesh-controller
 /postgres-provisioner
 /redis-provisioner
+# And where `go build` in cmd/mesh-controller leaves it (novox/hq issue 233).
+/cmd/mesh-controller/mesh-controller

cmd/mesh-builder/main.go

@@ -66,6 +66,11 @@ broker to take work from or a registry to publish into:
 
 Without --registry the artifacts stay in this machine's container runtime, named by the
 digest of their own configuration. The result is printed as JSON.
+
+  mesh-builder ready
+
+exits 0 once the agent running in this container is bound to its build work and pulls it, and
+1 before: its container's health check.
 `
 
 func run() error {
@@ -76,12 +81,18 @@ func run() error {
 			return nil
 		case "build":
 			return buildOnce(context.Background(), os.Args[2:])
+		case "ready":
+			// The container's health check (novox/hq issue 544): exits non-zero until the agent takes work.
+			return ready()
 		default:
 			fmt.Print(usage)
 			return nil
 		}
 	}
 
+	if err := notReady(); err != nil {
+		return err
+	}
 	credential, err := brokerFrom()
 	if err != nil {
 		return err
@@ -134,7 +145,8 @@ func run() error {
 	// **What an earlier holder here left goes before anything is taken** (novox/hq issue 306): a holder
 	// recreated mid-check left the check's store and bus running, and the ask went to another machine.
 	h.removeLeftBehind()
-	machine := link.MachineOverNATSWith(js, on, seat, link.MachineOptions{Paused: h.Paused})
+	machine := link.MachineOverNATSWith(js, on, seat, link.MachineOptions{Paused: h.Paused,
+		Taking: func() { taking(seat) }})
 	defer machine.Close()
 
 	// The seat's verbs, on this machine's subjects. Only the seat that declares them: the retired
@@ -256,7 +268,13 @@ func answer(ctx context.Context, publisher builder.Publisher, on, workspace stri
 		v, err = builder.Check(building, builder.Command, checkSpecOf(request), workspace, registry, forgeFrom(), say)
 		if err == nil {
 			result.Check = &link.CheckOutcome{Verdict: v.Verdict, Summary: v.Summary, Report: v.Report,
-				Took: v.Took.Round(time.Second).String(), Gate: layerOf(v.Gate), RepoCheck: layerOf(v.Repo)}
+				Took: v.Took.Round(time.Second).String(), Gate: layerOf(v.Gate), RepoCheck: layerOf(v.Repo),
+				Head: v.Head, Trunk: v.Trunk, Beside: v.Beside}
+			// What each of a group's heads was judged as (novox/hq ADR 0323 §6).
+			for _, m := range v.Members {
+				result.Check.Members = append(result.Check.Members, link.CheckedMember{Owner: m.Owner, Repo: m.Repo,
+					Commit: m.Head, Trunk: m.Trunk})
+			}
 		}
 	} else if err == nil {
 		// The package-registry credential is a build input, so it is resolved before the clone: a
@@ -354,7 +372,7 @@ func checkSpecOf(request link.BuildRequest) builder.CheckSpec {
 	}
 	for _, m := range c.Members {
 		spec.Group = append(spec.Group, builder.GroupHead{Owner: m.Owner, Repo: m.Repo, Repository: m.Repository,
-			Ref: m.Ref, Paths: m.Paths})
+			Ref: m.Ref, Paths: m.Paths, Base: m.Base})
 	}
 	return spec
 }

cmd/mesh-builder/ready.go

@@ -0,0 +1,44 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+// **The build agent says it is ready** (novox/hq issue 544). It listens on nothing, so no http or tcp
+// check can see it work; it writes a mark once it is bound to its worker and pulls build work, and its
+// container's health check runs `mesh-builder ready`, which passes only while the mark is there. Without
+// it the node-engine could judge the agent only alive, and every walk that moved it waited out the whole
+// grace on each machine.
+//
+// The mark lives in the container's own temporary directory, never in the workspace the machine keeps:
+// a new container starts without it, and a restarted one removes it before it binds again.
+func readyMark() string { return filepath.Join(os.TempDir(), "mesh-builder.ready") }
+
+// notReady removes the mark: a holder starting is not taking work until it says so again.
+func notReady() error {
+	if err := os.Remove(readyMark()); err != nil && !errors.Is(err, os.ErrNotExist) {
+		return fmt.Errorf("cannot remove the mark that this agent takes build work (%s): %w", readyMark(), err)
+	}
+	return nil
+}
+
+// taking writes the mark. A mark that cannot be written is said, and the agent goes on building: its
+// check then says it is not ready, which is the truth the gate should hear.
+func taking(seat string) {
+	if err := os.WriteFile(readyMark(), []byte(seat+"\n"), 0o644); err != nil {
+		fmt.Fprintf(os.Stderr, "cannot mark that this agent takes build work (%s): %v\n", readyMark(), err)
+		return
+	}
+	fmt.Fprintf(os.Stderr, "taking build work from %s\n", seat)
+}
+
+// ready is the health check: nil when this container's agent is bound and pulling build work.
+func ready() error {
+	if _, err := os.Stat(readyMark()); err != nil {
+		return fmt.Errorf("not taking build work yet: %s is not there", readyMark())
+	}
+	return nil
+}

cmd/mesh-builder/ready_test.go

@@ -0,0 +1,32 @@
+package main
+
+import (
+	"os"
+	"testing"
+)
+
+// The health check passes only between the agent saying it takes work and its next start (novox/hq
+// issue 544).
+func TestTheAgentIsReadyOnlyOnceItTakesWork(t *testing.T) {
+	t.Setenv("TMPDIR", t.TempDir())
+	if err := ready(); err == nil {
+		t.Fatal("an agent that never took work is ready")
+	}
+	taking("mesh-build-machine")
+	if err := ready(); err != nil {
+		t.Fatalf("an agent taking work is not ready: %v", err)
+	}
+	// Started again, it is not ready until it binds again.
+	if err := notReady(); err != nil {
+		t.Fatal(err)
+	}
+	if err := ready(); err == nil {
+		t.Fatal("an agent starting again is ready before it takes work")
+	}
+	if err := notReady(); err != nil {
+		t.Fatalf("removing a mark that is not there failed: %v", err)
+	}
+	if _, err := os.Stat(readyMark()); err == nil {
+		t.Fatal("the mark is still there")
+	}
+}

cmd/mesh-controller/acts.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"github.com/novox/mesh-controller/internal/broker"
+	"io"
 	"slices"
 	"sort"
 	"strings"
@@ -54,6 +55,9 @@ func assignWith(ctx context.Context, open *stores, node string, opts assignOptio
 	if err := refusedMovingTheController(modules); err != nil {
 		return "", err
 	}
+	// Every line of the answer comes from the one resolution after the write (novox/hq issue 237):
+	// what the reads before it would say about a machine left out is not the answer's.
+	ctx = leftOutSaidBy(ctx, io.Discard)
 	// Held while it is recorded, so it cannot land between a converge's preview and its flip and
 	// be taken without ever having been previewed (novox/hq ADR 0100).
 	ctx, release, err := holdNodes(ctx, open, []string{node})
@@ -125,22 +129,28 @@ func assignWith(ctx context.Context, open *stores, node string, opts assignOptio
 	for _, line := range settled {
 		answer += "\n  " + line
 	}
-	// What this act changed about this node's unmet seat dependencies, and nothing else (novox/hq
-	// ADR 0207): a dependency of a module just assigned, or one this assignment met. The rest of the
-	// node's list, and every other node's, is `status`'s.
-	for _, line := range unheldChange(shelf, node, before, append(append([]string(nil), before...), added...)) {
-		answer += "\n  " + line
-	}
 	// Its bus credential, in the same act (novox/hq issue 203): an assignment pushed before its
 	// credential exists delivers a process that cannot authenticate and crash-loops until somebody
 	// runs a second verb and a second push. Issued here when the module speaks on the bus and has
 	// no credential yet; kept when it has one, so re-assigning rotates nothing.
+	var issued []string
 	for _, module := range added {
 		if line := issueOnAssign(ctx, open, node, module); line != "" {
-			answer += "\n  " + line
+			issued = append(issued, line)
 		}
 	}
-	plan, _, err := planFor(ctx, open, node)
+	// **The one resolution the rest of the answer is said from** (novox/hq issue 237), taken after
+	// the write: what this act changed about this node's unmet seat dependencies, and nothing else
+	// (novox/hq ADR 0207) — a dependency of a module just assigned, or one this assignment met; the
+	// rest of the node's list, and every other node's, is `status`'s — and whether the node resolves.
+	after := resolvedAfter(ctx, open, shelf, node)
+	for _, line := range unheldChangeTo(shelf, node, before, after.modules, after.unheld) {
+		answer += "\n  " + line
+	}
+	for _, line := range issued {
+		answer += "\n  " + line
+	}
+	plan, err := after.plan, after.err
 	if err != nil {
 		// Kept, and still refused. Both halves are the answer, and the rest of the mesh is still
 		// worth reporting: this machine's refusal is rarely the only consequence.
@@ -218,6 +228,8 @@ func unassign(ctx context.Context, open *stores, node string, modules ...string)
 	if len(modules) == 0 {
 		return "", fmt.Errorf("unassign %s names no module", node)
 	}
+	// One resolution after the write, as assign's answer (novox/hq issue 237).
+	ctx = leftOutSaidBy(ctx, io.Discard)
 	ctx, release, err := holdNodes(ctx, open, []string{node})
 	if err != nil {
 		return "", err
@@ -262,15 +274,22 @@ func unassign(ctx context.Context, open *stores, node string, modules ...string)
 	}
 	answer := fmt.Sprintf("%s no longer runs %s — run `push %s` to make it so",
 		node, strings.Join(modules, ", "), node)
-	var left []string
-	for _, a := range assigned {
-		if !slices.Contains(modules, a) {
-			left = append(left, a)
-		}
-	}
-	for _, line := range unheldChange(shelf, node, assigned, left) {
+	after := resolvedAfter(ctx, open, shelf, node)
+	for _, line := range unheldChangeTo(shelf, node, assigned, after.modules, after.unheld) {
 		answer += "\n  " + line
 	}
+	// Whether the node itself still resolves, from the same resolution: before, only the rest of the
+	// mesh's reads said it, on standard error and once per other machine.
+	if after.err != nil {
+		if unresolvable(after.err) {
+			answer += fmt.Sprintf("\n  but %s does not resolve now, so nothing will be sent to it:", node)
+		} else {
+			answer += fmt.Sprintf("\n  but whether %s still resolves could not be read:", node)
+		}
+		for _, line := range strings.Split(strings.TrimRight(after.err.Error(), "\n"), "\n") {
+			answer += "\n    " + strings.TrimSpace(line)
+		}
+	}
 	// What it leaves behind that is irreplaceable is kept and retired, never removed (novox/hq ADR 0233).
 	for _, line := range keptOnUnassign(ctx, open.inventory, node, modules) {
 		answer += "\n  " + line
@@ -278,6 +297,39 @@ func unassign(ctx context.Context, open *stores, node string, modules ...string)
 	return answer + blockedElsewhere(ctx, open, node), nil
 }
 
+// afterAct is the one resolution of a node an act's answer is said from, taken after its write
+// (novox/hq issue 237): the plan or why there is none, the modules it has on the node, and its unmet
+// seat dependencies.
+type afterAct struct {
+	plan    catalogue.Resolution
+	err     error
+	modules []string
+	unheld  []catalogue.Unheld
+}
+
+// resolvedAfter resolves the node as `plan` does, once, after the act's write. When the node resolves,
+// its modules and unmet seat dependencies are the resolution's — the closure, so a holder pulled in by
+// a requirement counts as `plan` counts it. When it does not, they are judged over the assignments read
+// after the write, which can only find more unmet than the closure would: a seat said held there is
+// held in the closure too.
+func resolvedAfter(ctx context.Context, open *stores, shelf map[string]catalogue.Manifest, node string) afterAct {
+	plan, _, err := planFor(ctx, open, node)
+	if err == nil {
+		out := afterAct{plan: plan, unheld: plan.Unheld}
+		for _, m := range plan.Modules {
+			out.modules = append(out.modules, m.Module)
+		}
+		return out
+	}
+	out := afterAct{err: err}
+	assigned, readErr := open.inventory.Assigned(ctx, node)
+	if readErr != nil {
+		return out
+	}
+	out.modules, out.unheld = assigned, unheldOver(shelf, node, assigned)
+	return out
+}
+
 // splitModules is a surface's one `module` field as the modules it names: several, comma-separated,
 // are one act (novox/hq ADR 0207), so the holders that depend on each other go on together from the
 // command API and the controller seat's verbs as they do from the command line.

cmd/mesh-controller/apply_failing.go

@@ -0,0 +1,118 @@
+package main
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// kindApplyFailing is S21's kind: a machine whose declarations have been refused, or applied only in part,
+// for longer than one apply interval (novox/hq issue 233).
+const kindApplyFailing = "apply-failing"
+
+// applyEvery is how often a node-engine applies what it was last told when nothing new arrives: its
+// ReconcileEvery. A failure still there after one more of them is not one the next apply clears.
+const applyEvery = 5 * time.Minute
+
+// packageManagerKey is how a node-engine names a package manager that does not answer among what failed
+// (mesh-host's probe.go): "the package manager (pacman)".
+const packageManagerKey = "the package manager ("
+
+// watchApplyFailing is S21: **a machine that does not apply what it was sent is said by the mesh, not only
+// to someone who asks for `status`** (novox/hq issue 233, issue 187's family). A workstation refused every
+// declaration for an hour and a half because its package manager did not answer, and the mesh's only word
+// on it was a line in `status`. Raised once the machine's first report of this failure is older than one apply
+// interval **while the machine is heard** — judged by time, not by how many reports said it: a node-engine
+// says a re-apply only when how it went changed, so the same failure is one report however long it lasts.
+// Names the refusal's or the failure's words; cleared by the clean apply the node-engine then says. Not while
+// the machine is silent, asleep or not known: S1 says silent, and asleep is not lost.
+func watchApplyFailing(f *signalFacts) []conditions.Observation {
+	heard := map[string]bool{}
+	for _, m := range f.machines {
+		if !m.asleep() && !m.lastHeard.IsZero() && f.now.Sub(m.lastHeard) <= heartbeatBound(m.every) {
+			heard[m.name] = true
+		}
+	}
+	var out []conditions.Observation
+	for _, d := range f.doing {
+		if !d.Wrong() || d.Since == nil || f.now.Sub(*d.Since) <= applyEvery || !heard[d.Node] {
+			continue
+		}
+		out = append(out, applyFailing(d, f.now))
+	}
+	return out
+}
+
+// applyFailing is one machine's S21 condition.
+func applyFailing(d inventory.Doing, now time.Time) conditions.Observation {
+	m := d.Node
+	since := d.Since.UTC().Format("2006-01-02 15:04 MST")
+	o := conditions.Observation{Scope: conditions.ScopeMachine, ID: m, Kind: kindApplyFailing, Machine: m,
+		Severity: conditions.Warning, Said: doingWords(d),
+		Resolved: m + " applies what it is sent again"}
+	how := "refused its declaration whole"
+	if d.Outcome != inventory.OutcomeRefused {
+		how = "applied its declaration only in part"
+	}
+	o.Summary = fmt.Sprintf("%s has %s since %s (bound %s): %s", m, how, since, ago(applyEvery), failedNames(d))
+	o.Headline = m + " is not applying its update"
+	o.Explanation = fmt.Sprintf("%s has %s for %s, and trying again has not helped. The details say what fails.",
+		m, plainHow(d), humanDuration(now.Sub(*d.Since)))
+	if tool := unansweringTool(d); tool != "" {
+		o.Summary = fmt.Sprintf("%s: %s does not answer, so no package reaches it; everything else it was sent "+
+			"is applied, since %s (bound %s)", m, tool, since, ago(applyEvery))
+		o.Headline = fmt.Sprintf("%s cannot install packages", m)
+		o.Explanation = fmt.Sprintf("The package manager on %s (%s) has not answered for %s, so no package reaches "+
+			"it. Everything else is still applied, so an update that repairs it can land; if none does, it needs a "+
+			"look on the machine.", m, tool, humanDuration(now.Sub(*d.Since)))
+	}
+	return o
+}
+
+// plainHow is how a machine failed, as the operator reads it.
+func plainHow(d inventory.Doing) string {
+	if d.Outcome == inventory.OutcomeRefused {
+		return "refused every update"
+	}
+	return "applied its updates only in part"
+}
+
+// unansweringTool is the package manager a machine said does not answer, or "".
+func unansweringTool(d inventory.Doing) string {
+	for _, r := range d.Failed {
+		if rest, ok := strings.CutPrefix(r.ID, packageManagerKey); ok {
+			return strings.TrimSuffix(rest, ")")
+		}
+	}
+	return ""
+}
+
+// failedNames is what failed, by name: the refusal, or the failed resources' ids.
+func failedNames(d inventory.Doing) string {
+	if d.Outcome == inventory.OutcomeRefused {
+		return "refused"
+	}
+	ids := make([]string, 0, len(d.Failed))
+	for _, r := range d.Failed {
+		ids = append(ids, r.ID)
+	}
+	sort.Strings(ids)
+	return "failed " + strings.Join(ids, ", ")
+}
+
+// doingWords is the machine's own words on what failed: the evidence, kept inside the mesh.
+func doingWords(d inventory.Doing) string {
+	if d.Outcome == inventory.OutcomeRefused {
+		return "refused: " + oneLine(d.Refused)
+	}
+	var parts []string
+	for _, r := range d.Failed {
+		parts = append(parts, r.ID+": "+oneLine(r.Error))
+	}
+	sort.Strings(parts)
+	return strings.Join(parts, "; ")
+}

cmd/mesh-controller/apply_failing_test.go

@@ -0,0 +1,123 @@
+package main
+
+import (
+	"context"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// unansweringPackageManager is anchor's last report as the workstation's read on 2026-10-04, once its
+// node-engine applies the rest (novox/hq issue 233): the package failed and the package manager did not answer,
+// the same failure on times reports since for before now.
+func unansweringPackageManager(now time.Time, forHowLong time.Duration, times int) inventory.Doing {
+	since := now.Add(-forHowLong)
+	return inventory.Doing{Node: "anchor", Outcome: inventory.OutcomeFailed, At: now.Add(-time.Second),
+		Since: &since, Times: times, Applied: 41, Failed: []inventory.FailedResource{
+			{ID: "apply", Error: `applying "pacman.base": nothing can be said about "base": this is the arch host and ` +
+				"pacman does not answer here. Either this machine is not Arch, or its package database is broken: " +
+				"pacman exited 1: error: config file /etc/pacman.conf could not be read: No such file or directory"},
+			{ID: "the package manager (pacman)", Error: "pacman does not answer here, so every package in this " +
+				"declaration fails and the rest of it is applied (novox/hq issue 233): pacman exited 1: error: config " +
+				"file /etc/pacman.conf could not be read: No such file or directory"}}}
+}
+
+// **A machine whose package manager does not answer is raised by the mesh itself, naming the tool and the
+// probe's words** (novox/hq issue 233): the words in the evidence, the path kept out of the summary.
+func TestAPackageManagerThatDoesNotAnswerIsRaisedNamingItsWords(t *testing.T) {
+	now := time.Date(2026, 10, 4, 14, 0, 0, 0, time.UTC)
+	f := calm(now)
+	f.doing = []inventory.Doing{unansweringPackageManager(now, 90*time.Minute, 18)}
+	got := watchApplyFailing(f)
+	if len(got) != 1 {
+		t.Fatalf("raised %d conditions, want one: %+v", len(got), got)
+	}
+	o := got[0]
+	if o.Key() != "machine.anchor.apply-failing" || o.Machine != "anchor" {
+		t.Errorf("the condition is not the machine's: %s", o.Key())
+	}
+	if !strings.Contains(o.Summary, "pacman does not answer") || !strings.Contains(o.Summary, "since 2026-10-04 12:30") {
+		t.Errorf("the summary does not name the tool and since when: %s", o.Summary)
+	}
+	if strings.Contains(o.Summary, "/etc/") {
+		t.Errorf("the summary carries a path, which belongs in the evidence: %s", o.Summary)
+	}
+	if !strings.Contains(o.Said, "could not be read") {
+		t.Errorf("the evidence does not carry the probe's words: %s", o.Said)
+	}
+	if !strings.Contains(o.Headline, "cannot install packages") || o.Explanation == "" || o.Resolved == "" {
+		t.Errorf("the plain words do not say it: %+v", o)
+	}
+}
+
+// **A whole refusal is raised too**, with the node-engine's words: what the workstation's report said before the
+// node-engine applied the rest.
+func TestARefusalThatGoesOnIsRaised(t *testing.T) {
+	now := time.Date(2026, 10, 4, 14, 0, 0, 0, time.UTC)
+	since := now.Add(-time.Hour)
+	f := calm(now)
+	f.doing = []inventory.Doing{{Node: "anchor", Outcome: inventory.OutcomeRefused, Since: &since, Times: 12,
+		Refused: "this is the arch host and pacman does not answer here", At: now.Add(-time.Minute)}}
+	got := watchApplyFailing(f)
+	if len(got) != 1 || !strings.Contains(got[0].Summary, "refused its declaration whole") ||
+		!strings.Contains(got[0].Said, "pacman does not answer") {
+		t.Fatalf("a refusal that went on for an hour was not raised with its words: %+v", got)
+	}
+}
+
+// **Judged by time while the machine is heard, not by how many reports said it** (review of novox/hq issue 233):
+// a node-engine says the same failure once, so one report an apply interval old is a fault that goes on; one
+// younger is not yet; and a silent or sleeping machine is S1's.
+func TestOneReportOlderThanAnApplyIsRaisedAndAQuietMachineIsNot(t *testing.T) {
+	now := time.Date(2026, 10, 4, 14, 0, 0, 0, time.UTC)
+	f := calm(now)
+	f.doing = []inventory.Doing{unansweringPackageManager(now, 6*time.Minute, 1)}
+	if got := watchApplyFailing(f); len(got) != 1 {
+		t.Errorf("one report of a failure six minutes old was not raised: %+v", got)
+	}
+	f.doing = []inventory.Doing{unansweringPackageManager(now, 4*time.Minute, 1)}
+	if got := watchApplyFailing(f); len(got) != 0 {
+		t.Errorf("a failure four minutes old was raised before one apply could clear it: %+v", got)
+	}
+	f.doing = []inventory.Doing{unansweringPackageManager(now, time.Hour, 1)}
+	f.machines[0].lastHeard = now.Add(-time.Hour)
+	if got := watchApplyFailing(f); len(got) != 0 {
+		t.Errorf("a silent machine was raised for its last report: %+v", got)
+	}
+	f = calm(now)
+	f.doing = []inventory.Doing{unansweringPackageManager(now, time.Hour, 1)}
+	f.doing[0].Node = "a-machine-the-mesh-does-not-know"
+	if got := watchApplyFailing(f); len(got) != 0 {
+		t.Errorf("a machine not heard of was raised: %+v", got)
+	}
+}
+
+// **A failed re-apply followed by a clean one clears S21** (review of novox/hq issue 233): the node-engine says
+// the clean re-apply, the store keeps it as applied with no failure since, and the condition the failure raised
+// is cleared through the keeper on the next tick.
+func TestACleanReapplyAfterAFailedOneClearsTheCondition(t *testing.T) {
+	now := time.Date(2026, 10, 4, 14, 0, 0, 0, time.UTC)
+	store := conditions.NewInMemory()
+	k := conditions.NewKeeper(t.Context(), conditions.Options{Store: store, History: store,
+		Teller: &conditions.Told{}, Now: func() time.Time { return now }})
+	defer k.Close(context.Background())
+	w := &watchdogs{keeper: k, started: now.Add(-time.Hour)}
+
+	failing := calm(now)
+	failing.doing = []inventory.Doing{unansweringPackageManager(now, 20*time.Minute, 1)}
+	w.see(t.Context(), failing)
+	open, err := k.Open(t.Context())
+	if err != nil || len(open) != 1 || open[0].Kind != kindApplyFailing {
+		t.Fatalf("the failed re-apply raised %+v (%v), want apply-failing", open, err)
+	}
+
+	clean := calm(now.Add(5 * time.Minute))
+	clean.doing = nil // the clean re-apply recorded: NotDoingWhatTheyWereTold no longer lists the machine
+	w.see(t.Context(), clean)
+	if open, _ := k.Open(t.Context()); len(open) != 0 {
+		t.Fatalf("the condition stayed open after the clean re-apply: %+v", open)
+	}
+}

cmd/mesh-controller/asker.go

@@ -213,6 +213,8 @@ type asker struct {
 
 	saidNoRouter bool
 	saidNoGrant  bool
+	// saidGrantCaveat is whether a grant held with a caveat was said, so it is said once.
+	saidGrantCaveat bool
 
 	mu     sync.Mutex
 	nudged chan struct{}
@@ -317,6 +319,13 @@ func (a *asker) reconcile(ctx context.Context) error {
 			}
 			return a.sayUnasked(ctx, unasked, "the bus does not hold the controller's grant to ask yet: "+why)
 		}
+		if why != "" && !a.saidGrantCaveat {
+			// Held, with a caveat worth one line (an older bus module cannot confirm the reload).
+			a.logf("the controller asks: %s", why)
+			a.saidGrantCaveat = true
+		} else if why == "" {
+			a.saidGrantCaveat = false
+		}
 		a.saidNoGrant = false
 	}
 	channels := ""

cmd/mesh-controller/asker_test.go

@@ -12,6 +12,7 @@ import (
 
 	"git.novox.be/novox/mesh-sdk/go/asks"
 
+	"github.com/novox/mesh-controller/internal/broker"
 	"github.com/novox/mesh-controller/internal/conditions"
 	"github.com/novox/mesh-controller/internal/link"
 )
@@ -808,3 +809,207 @@ func TestARefusalIsAskedAgainAndTheUndeliveredConditionClearsOnceTaken(t *testin
 		t.Errorf("the explanation says its verdict twice: %q", e)
 	}
 }
+
+// hq issue 353, the review: the bus holds the controller's grant to ask only when both facts hold — the mesh
+// composes the controller's own grant, and the bus's module says it is in force on the running server — and
+// each fact not known is not held, said with why.
+func TestTheGrantIsHeldOnlyWhenComposedAndInForceOnTheBus(t *testing.T) {
+	yes := func(context.Context) (bool, string, error) { return true, "", nil }
+	no := func(why string) grantJudge {
+		return func(context.Context) (bool, string, error) { return false, why, nil }
+	}
+	broken := func(context.Context) (bool, string, error) { return false, "", errors.New("the store is away") }
+	for _, c := range []struct {
+		name              string
+		composed, inForce grantJudge
+		held              bool
+		says              string
+	}{
+		{"composed and in force", yes, yes, true, ""},
+		{"not composed", no("no router is assigned"), yes, false, "no router is assigned"},
+		{"composed, written, not reloaded", yes, no("the server has not reloaded"), false, "has not reloaded"},
+		{"the composition unknown", broken, yes, false, "could not be worked out: the store is away"},
+		{"the bus unknown", yes, broken, false, "could not be worked out: the store is away"},
+		{"nothing judges the bus", yes, nil, false, "not judged"},
+	} {
+		held, why, err := grantHeldBy(c.composed, c.inForce, time.Now)(context.Background())
+		if err != nil || held != c.held || !strings.Contains(why, c.says) {
+			t.Errorf("%s: held %v (%q, %v)", c.name, held, why, err)
+		}
+	}
+	// Remembered for grantLookEvery, then judged again.
+	now := time.Date(2026, 10, 9, 18, 0, 0, 0, time.UTC)
+	inForce := false
+	judge := grantHeldBy(yes, func(context.Context) (bool, string, error) { return inForce, "not yet", nil },
+		func() time.Time { return now })
+	if held, _, _ := judge(context.Background()); held {
+		t.Fatal("held before the bus enforces it")
+	}
+	inForce = true
+	if held, _, _ := judge(context.Background()); held {
+		t.Error("judged again inside grantLookEvery")
+	}
+	now = now.Add(grantLookEvery)
+	if held, _, _ := judge(context.Background()); !held {
+		t.Error("not judged again after grantLookEvery")
+	}
+}
+
+// The controller's own grant, as composed: present while a router that takes asks is assigned, absent
+// otherwise — whatever else in the user list changes.
+func TestTheControllersOwnGrantToAskIsReadFromTheComposition(t *testing.T) {
+	router := broker.Declared{Module: "messenger", Holds: []broker.Seat{{Name: broker.AsksSeat, Scope: "mesh",
+		Accepts: []string{"ask", "cancel"}, Emits: []string{"decided"}, ByCaller: []string{"ask", "cancel", "decided"}}}}
+	other := broker.Declared{Module: "dunst"}
+	with := broker.Records{Nodes: []string{"anchor"}, Assigned: map[string][]broker.Declared{"anchor": {router, other}}}
+	without := broker.Records{Nodes: []string{"anchor"}, Assigned: map[string][]broker.Declared{"anchor": {other}}}
+	if may, err := controllerMayAsk(with); err != nil || !may {
+		t.Errorf("with a router assigned: %v %v", may, err)
+	}
+	if may, err := controllerMayAsk(without); err != nil || may {
+		t.Errorf("with no router assigned: %v %v", may, err)
+	}
+}
+
+// The bus module's answer, with the record's word on the list sent as the check only where the answer does
+// not settle it (reviews 22 and 31 of PR 188); each way it is not held names its own remedy.
+func TestTheBusModulesAnswerNamesTheRemedyForEachCase(t *testing.T) {
+	const (
+		reloaded   = `{"allowed":true,"in_force":true,"file_written":"2026-10-09T15:55:56Z","server_loaded":"2026-10-09T15:56:05Z"}`
+		notLoaded  = `{"allowed":true,"in_force":false,"why":"the user list on the machine allows it, and the server has not reloaded since it was written","file_written":"2026-10-09T15:55:56Z","server_loaded":"2026-10-09T15:50:00Z"}`
+		noVarz     = `{"allowed":true,"in_force":false,"why":"the server's last configuration load could not be read: refused"}`
+		noStat     = `{"allowed":true,"in_force":false,"why":"when the bus's user list was written could not be read inside mesh-broker-nats: exit 1"}`
+		notAllowed = `{"allowed":false,"in_force":false,"why":"the user list on the machine does not allow it"}`
+	)
+	current := busListState{Machine: "anchor"}
+	behind := busListState{Machine: "anchor", Behind: true}
+	stepped := busListState{Machine: "anchor", Behind: true, BusStep: "sending anchor would replace the bus; `bus upgrade --why …`"}
+	uncomposed := busListState{Machine: "anchor", Behind: true, Uncomposed: errors.New("module foo requires a provision nobody provides")}
+	for _, c := range []struct {
+		name, answer string
+		askErr       error
+		list         busListState
+		listErr      error
+		held         bool
+		says, not    string
+	}{
+		{"in force", reloaded, nil, behind, nil, true, "", "push"},
+		{"written, not reloaded", notLoaded, nil, current, nil, false, "within about 5 s", "push"},
+		{"in force not known: varz", noVarz, nil, current, nil, false, "is not known: the server's last configuration load", "wait"},
+		{"in force not known: stat", noStat, nil, current, nil, false, "is not known: when the bus's user list was written", "wait"},
+		{"not allowed, list behind", notAllowed, nil, behind, nil, false, "`push anchor` carries it", "5 s"},
+		{"not allowed, bus step pending", notAllowed, nil, stepped, nil, false, "`bus upgrade", "`push anchor`"},
+		{"not allowed, list uncomposed", notAllowed, nil, uncomposed, nil, false, "`plan anchor`", "`push anchor`"},
+		{"older module, allowed, list current", `{"allowed":true}`, nil, current, nil, true, "not confirmed", "push"},
+		{"older module, allowed, list behind", `{"allowed":true}`, nil, behind, nil, true, "not confirmed", "push"},
+		{"older module, allowed, list unknown", `{"allowed":true}`, nil, current, errors.New("the store is away"), true, "`bus upgrade`", "push"},
+		{"older module, not allowed, list behind", `{"allowed":false}`, nil, behind, nil, false, "`push anchor` carries it", "5 s"},
+		{"module cannot answer, list current", "", errors.New("no responders"), current, nil, true, "could not answer", "push"},
+		{"module cannot answer, list behind", "", errors.New("no responders"), behind, nil, false, "`push anchor` carries it", ""},
+		{"module cannot answer, list unknown", "", errors.New("no responders"), current, errors.New("the store is away"), false, "could not be worked out", ""},
+		{"answer unreadable, list behind", `not json`, nil, behind, nil, false, "could not be read", ""},
+	} {
+		judge := busGrantBy(
+			func(context.Context) (string, json.RawMessage, error) {
+				return "anchor", json.RawMessage(c.answer), c.askErr
+			},
+			func(context.Context) (busListState, error) { return c.list, c.listErr })
+		held, why, _ := judgeGrantOnce(judge)
+		if held != c.held || !strings.Contains(why, c.says) || (c.not != "" && strings.Contains(why, c.not)) {
+			t.Errorf("%s: held %v (%q)", c.name, held, why)
+		}
+	}
+	none := busGrantBy(func(context.Context) (string, json.RawMessage, error) { return "", nil, nil }, nil)
+	if held, why, _ := judgeGrantOnce(none); held || !strings.Contains(why, "no module holds the bus") {
+		t.Errorf("no bus: held %v (%q)", held, why)
+	}
+}
+
+// judgeGrantOnce is the whole judgement with the composed grant held, as the asker makes it.
+func judgeGrantOnce(bus grantJudge) (bool, string, error) {
+	yes := func(context.Context) (bool, string, error) { return true, "", nil }
+	return grantHeldBy(yes, bus, time.Now)(context.Background())
+}
+
+// The orders reviews 22 and 31 of PR 188 found: this controller live before the bus module that answers
+// in_force, with the bus's machine behind on its list — and, after mesh-catalog #166 merged, unpushable until a
+// person's bus upgrade. An older module that allows the ask asks (once, with the caveat said); a new module that
+// has not reloaded names the wait, not a push; one that cannot say whether it reloaded names what is not known.
+func TestAnOlderBusModuleNeitherSilencesTheAsksNorNamesTheWrongRemedy(t *testing.T) {
+	for _, c := range []struct {
+		name, answer string
+		list         busListState
+		asks         bool
+		says, not    string
+	}{
+		{"older module, list current", `{"allowed":true}`, busListState{Machine: "anchor"}, true, "not confirmed", ""},
+		{"older module, list behind, bus step pending", `{"allowed":true}`,
+			busListState{Machine: "anchor", Behind: true, BusStep: "a planned step"}, true, "not confirmed", ""},
+		{"new module, not reloaded",
+			`{"allowed":true,"in_force":false,"why":"not reloaded","file_written":"2026-10-09T15:55:56Z","server_loaded":"2026-10-09T15:50:00Z"}`,
+			busListState{Machine: "anchor"}, false, "within about 5 s", "push"},
+		{"new module, reload not known", `{"allowed":true,"in_force":false,"why":"the server's last configuration load could not be read: refused"}`,
+			busListState{Machine: "anchor"}, false, "is not known", "wait"},
+	} {
+		t.Run(c.name, func(t *testing.T) {
+			r := newAskerRig(t)
+			var said []string
+			r.a.logf = func(f string, a ...any) { said = append(said, fmt.Sprintf(f, a...)) }
+			var raised [][]conditions.Observation
+			r.a.raise = func(_ context.Context, obs []conditions.Observation) error {
+				raised = append(raised, obs)
+				return nil
+			}
+			yes := func(context.Context) (bool, string, error) { return true, "", nil }
+			r.a.grantHeld = grantHeldBy(yes, busGrantBy(
+				func(context.Context) (string, json.RawMessage, error) {
+					return "anchor", json.RawMessage(c.answer), nil
+				},
+				func(context.Context) (busListState, error) { return c.list, nil }),
+				func() time.Time { return r.now })
+			r.open = []conditions.Condition{heldCondition()}
+			_ = r.a.reconcile(context.Background())
+			_ = r.a.reconcile(context.Background())
+			sent := r.asksSent(t)
+			if c.asks {
+				if len(sent) != 1 || sent[0].About != heldCondition().Key {
+					t.Fatalf("not asked: %+v", sent)
+				}
+				n := 0
+				for _, s := range said {
+					if strings.Contains(s, c.says) {
+						n++
+					}
+				}
+				if n != 1 {
+					t.Errorf("the caveat said %d times: %q", n, said)
+				}
+				return
+			}
+			if len(sent) != 0 {
+				t.Fatalf("asked while the bus does not hold the grant: %+v", sent)
+			}
+			if len(raised) == 0 || len(raised[len(raised)-1]) != 1 ||
+				raised[len(raised)-1][0].Kind != "asks-undelivered" {
+				t.Fatalf("not said as undelivered: %+v", raised)
+			}
+			summary := raised[len(raised)-1][0].Summary
+			if !strings.Contains(summary, c.says) || (c.not != "" && strings.Contains(summary, c.not)) {
+				t.Errorf("the condition names the wrong remedy: %q", summary)
+			}
+		})
+	}
+}
+
+// The serving asker is wired to the real judgement: with records and a bus it cannot read, the grant is not
+// held, and so nothing is asked (a stub saying yes, or no judgement at all, would ask).
+func TestTheServingAskerJudgesTheGrantForReal(t *testing.T) {
+	a := servingAsker(&stores{}, nil, nil, nil)
+	if a.grantHeld == nil {
+		t.Fatal("the serving asker does not judge the bus's grant")
+	}
+	held, why, err := a.grantHeld(context.Background())
+	if err != nil || held || !strings.Contains(why, "could not be worked out") {
+		t.Errorf("held %v (%q, %v) with nothing to read", held, why, err)
+	}
+}

cmd/mesh-controller/asker_wire.go

@@ -235,12 +235,27 @@ func routerHereIn(inv *inventory.Inventory) func(ctx context.Context) (bool, err
 	}
 }
 
-// grantHeldIn says whether the bus holds the controller's grant to ask (novox/hq issue 353): the user list the
-// machine holding the bus was last sent is the one the mesh composes now (brokerBehind, the same judgement a
-// push makes to send that machine first). While it is behind, the controller's ask is refused by the bus,
-// whatever the record says of the router, so nothing is asked and the operator is told to push that machine.
-// Judged at most every grantLookEvery: composing the list resolves the bus's machine whole.
-func grantHeldIn(open *stores) func(ctx context.Context) (bool, string, error) {
+// grantHeldIn says whether the bus holds the controller's grant to ask (novox/hq issue 353), judged on the two
+// facts that make it so, and failing closed on each:
+//
+//  1. **composed**: the user list the mesh composes now grants the controller itself to publish its ask
+//     (controllerMayAsk) — the controller's own grant, not whether any user of the list changed;
+//  2. **in force**: the bus's own module, on the machine holding the bus, says the user list there allows it
+//     and the server reloaded after that list was written (the nats module's `nats_user_can`, `in_force`) — a
+//     list sent is not a list the bus enforces until it reloads.
+//
+// Anything that cannot be worked out is not held, with why, so the conditions that need the operator are said
+// as undelivered rather than asked into a refusal.
+func grantHeldIn(open *stores, conn *nats.Conn) func(ctx context.Context) (bool, string, error) {
+	return grantHeldBy(composedGrantIn(open), busGrantIn(open, conn), time.Now)
+}
+
+// grantJudge is one of the two facts: whether it holds, and why not.
+type grantJudge func(ctx context.Context) (bool, string, error)
+
+// grantHeldBy is the judgement over the two facts, remembered for grantLookEvery: composing the list resolves
+// the bus's machine whole, and asking the bus's module is a call.
+func grantHeldBy(composed, inForce grantJudge, now func() time.Time) func(ctx context.Context) (bool, string, error) {
 	var mu sync.Mutex
 	var at time.Time
 	var held bool
@@ -248,22 +263,251 @@ func grantHeldIn(open *stores) func(ctx context.Context) (bool, string, error) {
 	return func(ctx context.Context) (bool, string, error) {
 		mu.Lock()
 		defer mu.Unlock()
-		if !at.IsZero() && time.Since(at) < grantLookEvery {
+		if !at.IsZero() && now().Sub(at) < grantLookEvery {
 			return held, why, nil
 		}
-		machine, behind, err := brokerBehind(ctx, open, nil)
+		held, why = judgeGrant(ctx, composed, inForce)
+		at = now()
+		return held, why, nil
+	}
+}
+
+// judgeGrant is held only when both facts hold; an error is a fact not known, never a yes. A fact that holds
+// with a caveat (a reload not confirmed) gives that caveat as the why of a yes.
+func judgeGrant(ctx context.Context, composed, inForce grantJudge) (bool, string) {
+	var caveat []string
+	for _, fact := range []struct {
+		judge grantJudge
+		what  string
+	}{{composed, "whether the mesh composes the controller a grant to ask"}, {inForce, "whether the bus enforces it"}} {
+		if fact.judge == nil {
+			return false, fact.what + " is not judged here"
+		}
+		ok, why, err := fact.judge(ctx)
+		if err != nil {
+			return false, fact.what + " could not be worked out: " + err.Error()
+		}
+		if !ok {
+			return false, why
+		}
+		if why != "" {
+			caveat = append(caveat, why)
+		}
+	}
+	return true, strings.Join(caveat, "; ")
+}
+
+// controllerMayAsk says whether the controller's own grant, as composed from these records, lets it publish its
+// ask (ADR 0259 §3: composed while a router that takes asks under its asker's name is assigned).
+func controllerMayAsk(records broker.Records) (bool, error) {
+	users, err := broker.Users(records)
+	if err != nil {
+		return false, err
+	}
+	for _, u := range users {
+		if u.Kind != broker.KindController {
+			continue
+		}
+		perms, err := broker.PermissionsFor(u)
+		if err != nil {
+			return false, err
+		}
+		return broker.MayPublish(perms, asks.AskSubject(askerName)), nil
+	}
+	return false, errors.New("the composition holds no controller")
+}
+
+// composedGrantIn is the first fact, from the mesh's records.
+func composedGrantIn(open *stores) grantJudge {
+	return func(ctx context.Context) (bool, string, error) {
+		if open == nil || open.inventory == nil {
+			return false, "", errors.New("the mesh's records are not open")
+		}
+		records, err := open.inventory.BusRecords(ctx)
 		if err != nil {
 			return false, "", err
 		}
-		at, held, why = time.Now(), !behind, ""
-		if behind {
-			why = fmt.Sprintf("the bus's user list on %s is behind what the mesh composes, so the bus has not been "+
-				"given the controller's grant to ask; `push %s` carries it", machine, machine)
+		may, err := controllerMayAsk(records)
+		if err != nil || may {
+			return may, "", err
 		}
-		return held, why, nil
+		return false, "the mesh composes the controller no grant to ask: no router that takes asks under its " +
+			"asker's name is assigned", nil
 	}
 }
 
+// busGrantIn is the second fact, asked of the bus's own module on the machine holding the bus, with the check
+// main made before it (novox/hq issue 353, PR 186: is the user list sent to the bus's machine the one composed
+// now) kept for the cases the module's word does not settle.
+func busGrantIn(open *stores, conn *nats.Conn) grantJudge {
+	ask := func(ctx context.Context) (string, json.RawMessage, error) {
+		if open == nil || open.inventory == nil || conn == nil {
+			return "", nil, errors.New("the mesh's records or the bus are not open")
+		}
+		holders, err := seatHolders(ctx, open.inventory)
+		if err != nil {
+			return "", nil, err
+		}
+		h, held := holders[theBrokerSeat]
+		if !held || h.Node == "" || h.Module == "" {
+			return "", nil, nil
+		}
+		a, err := link.AskModuleToolOn(ctx, conn, h.Module, busUserCanTool, h.Node, map[string]any{
+			"user": broker.ControllerName, "action": "publish", "subject": asks.AskSubject(askerName)}, 15*time.Second)
+		if err != nil {
+			return h.Node, nil, err
+		}
+		if a.Error != "" {
+			return h.Node, nil, errors.New(a.Error)
+		}
+		return h.Node, a.Result, nil
+	}
+	list := func(ctx context.Context) (busListState, error) {
+		if open == nil || open.inventory == nil {
+			return busListState{}, errors.New("the mesh's records are not open")
+		}
+		s, err := brokerListState(ctx, open, nil)
+		if err != nil || s.Machine == "" || !s.Behind {
+			return s, err
+		}
+		step, err := busHeld(ctx, open.inventory, []string{s.Machine})
+		if err != nil {
+			return busListState{}, err
+		}
+		s.BusStep = step[s.Machine]
+		return s, nil
+	}
+	return busGrantBy(ask, list)
+}
+
+// busListState is the user list on the bus's machine as the controller's record knows it: whether the list
+// sent there is behind the one composed now, why it could not be composed, and the bus step a send there waits
+// on (that machine cannot be pushed until a person's `bus upgrade`).
+type busListState struct {
+	Machine    string
+	Behind     bool
+	Uncomposed error
+	BusStep    string
+}
+
+// remedy is the one thing that sends the bus's machine the list composed now: the plan's own reason when it
+// cannot be composed, the bus upgrade while sends there wait on it, and otherwise a push of that machine.
+func (s busListState) remedy(node string) string {
+	if s.Machine != "" {
+		node = s.Machine
+	}
+	switch {
+	case s.Uncomposed != nil:
+		return fmt.Sprintf("the user list for %s cannot be composed (%v); `plan %s` says what to fix first",
+			node, s.Uncomposed, node)
+	case s.BusStep != "":
+		return fmt.Sprintf("sends to %s wait on the bus's planned step, so a push will not carry it: %s", node, s.BusStep)
+	}
+	return fmt.Sprintf("`push %s` carries it", node)
+}
+
+// busGrantBy judges the bus's word, and names for each way it is not held the one thing that makes it held:
+//
+//   - **in force**: held;
+//   - **allowed, from a module older than `in_force`**: held, with the caveat that the reload is not confirmed.
+//     The file allows the publish, and the bus reloads within about 5 s of a change to it, so the worst case is
+//     one ask refused in those seconds, which is asked again (issue 369). The list check is not consulted:
+//     while a bus step is pending the bus's machine cannot be pushed, so any change to the composed list would
+//     read as behind for good and silence every ask until a person's bus upgrade (the review of PR 188);
+//   - **allowed, written, not reloaded** (the module gives both times): wait about 5 s;
+//   - **allowed, in force not known** (the module could not read a time): what is not known, said;
+//   - **not allowed, or the module cannot answer**: the list check decides — the remedy that sends the list
+//     when it is behind (busListState.remedy), and, for a module that cannot answer, held while the list sent
+//     is current, as main judged it.
+//
+// ask answers the machine holding the bus and its module's answer ("" when nothing holds the bus); list is the
+// record's word on the list sent to that machine.
+func busGrantBy(ask func(ctx context.Context) (string, json.RawMessage, error),
+	list func(ctx context.Context) (busListState, error)) grantJudge {
+	return func(ctx context.Context) (bool, string, error) {
+		node, raw, askErr := ask(ctx)
+		if askErr == nil && node == "" {
+			return false, "no module holds the bus, so nothing says what it enforces", nil
+		}
+		var answer busAnswer
+		if askErr == nil {
+			if answer, askErr = readBusAnswer(raw); askErr != nil {
+				askErr = fmt.Errorf("its answer could not be read: %w", askErr)
+			}
+		}
+		if askErr != nil {
+			if node == "" {
+				node = "the bus's machine"
+			}
+			s, err := list(ctx)
+			if err != nil {
+				return false, "", fmt.Errorf("the bus module on %s could not answer (%v), and whether the list sent "+
+					"there is the one composed now could not be worked out: %w", node, askErr, err)
+			}
+			if s.Behind {
+				return false, fmt.Sprintf("the bus module on %s could not answer (%v), and the user list sent there is "+
+					"behind what the mesh composes; %s", node, askErr, s.remedy(node)), nil
+			}
+			return true, fmt.Sprintf("the bus module on %s could not answer (%v); judged by the user list sent there, "+
+				"which is the one composed now", node, askErr), nil
+		}
+		notAllowed := func(older string) (bool, string, error) {
+			s, err := list(ctx)
+			if err != nil {
+				return false, "", fmt.Errorf("the user list on %s does not allow the controller to ask%s, and whether "+
+					"the list sent there is the one composed now could not be worked out: %w", node, older, err)
+			}
+			if s.Behind {
+				return false, fmt.Sprintf("the user list on %s does not allow the controller to ask%s: it is behind "+
+					"what the mesh composes; %s", node, older, s.remedy(node)), nil
+			}
+			return false, fmt.Sprintf("the user list on %s does not allow the controller to ask%s, though the list "+
+				"sent there is the one composed now; %s again", node, older, s.remedy(node)), nil
+		}
+		switch {
+		case answer.InForce == nil && answer.Allowed:
+			return true, fmt.Sprintf("the user list on %s allows the controller to ask, but its reload is not "+
+				"confirmed: the bus module there is older than the answer whether a grant is in force, and the bus "+
+				"upgrade (`bus upgrade`) carries one that confirms it", node), nil
+		case answer.InForce == nil:
+			return notAllowed(" (the bus module there is older than the answer whether a grant is in force)")
+		case !answer.Allowed:
+			return notAllowed("")
+		case *answer.InForce:
+			return true, "", nil
+		case answer.FileWritten != "" && answer.ServerLoaded != "":
+			return false, fmt.Sprintf("the bus on %s has the controller's grant to ask written (%s) but has not "+
+				"reloaded since (last load %s); it reloads in place within about 5 s, so nothing is to be done but wait",
+				node, answer.FileWritten, answer.ServerLoaded), nil
+		}
+		why := answer.Why
+		if why == "" {
+			why = "it gives no reason"
+		}
+		return false, fmt.Sprintf("the user list on %s allows the controller to ask, but whether the bus enforces it "+
+			"is not known: %s", node, why), nil
+	}
+}
+
+// busUserCanTool is the bus module's answer to whether a user may do something, and whether it is in force.
+const busUserCanTool = "nats_user_can"
+
+// busAnswer is the bus module's answer to busUserCanTool; InForce is nil from a module older than that field,
+// and FileWritten and ServerLoaded are given only when it could read both times (mesh-catalog's nats InForce).
+type busAnswer struct {
+	Allowed      bool   `json:"allowed"`
+	InForce      *bool  `json:"in_force"`
+	Why          string `json:"why"`
+	FileWritten  string `json:"file_written"`
+	ServerLoaded string `json:"server_loaded"`
+}
+
+func readBusAnswer(raw json.RawMessage) (busAnswer, error) {
+	var answer busAnswer
+	err := json.Unmarshal(raw, &answer)
+	return answer, err
+}
+
 // grantLookEvery is how often the bus's user list is judged against the one its machine was last sent.
 const grantLookEvery = 30 * time.Second
 
@@ -302,7 +546,19 @@ func startAsking(ctx context.Context, open *stores, server *link.Server, conn *n
 		fmt.Printf("the operator cannot be asked: %v\n", err)
 		return
 	}
-	a := &asker{
+	a := servingAsker(open, conn, js, keeper)
+	if err := server.Decides(a); err != nil {
+		fmt.Printf("the operator's answers cannot be heard, so nothing is asked: %v\n", err)
+		return
+	}
+	askerFrom = a
+	go a.keep(ctx)
+}
+
+// servingAsker is the serving controller's asker, wired to the mesh: what it reads, publishes, performs and
+// records, and the judgements it asks by — the bus's grant to ask among them (novox/hq issue 353).
+func servingAsker(open *stores, conn *nats.Conn, js jetstream.JetStream, keeper *conditions.Keeper) *asker {
+	return &asker{
 		open: keeper.Open,
 		silence: func(ctx context.Context, key string, d time.Duration, by, why string) error {
 			_, err := keeper.Silence(ctx, key, d, by, why)
@@ -322,7 +578,7 @@ func startAsking(ctx context.Context, open *stores, server *link.Server, conn *n
 		},
 		routerRecord: routerRecordOf(conn, open.inventory),
 		routerHere:   routerHereIn(open.inventory),
-		grantHeld:    grantHeldIn(open),
+		grantHeld:    grantHeldIn(open, conn),
 		channels:     channelsIn(open.inventory),
 		raise: func(ctx context.Context, obs []conditions.Observation) error {
 			return keeper.Reconcile(ctx, sourceAsker, obs)
@@ -330,10 +586,4 @@ func startAsking(ctx context.Context, open *stores, server *link.Server, conn *n
 		now:  time.Now,
 		logf: func(format string, args ...any) { fmt.Printf(format+"\n", args...) },
 	}
-	if err := server.Decides(a); err != nil {
-		fmt.Printf("the operator's answers cannot be heard, so nothing is asked: %v\n", err)
-		return
-	}
-	askerFrom = a
-	go a.keep(ctx)
 }

cmd/mesh-controller/batches.go

@@ -37,6 +37,11 @@ import (
 //     own commit, the newest first, one walk each, until one is delivered; the older ones are then answered
 //     by that one.
 //
+// **A merge waits only for a batch it shares something with** (novox/hq ADR 0304 decision 1, ADR 0306 decisions
+// 2 and 3, issue 525): it joins a batch it is related to, and one that is related to none and whose delivery
+// group has no member still to merge is a batch whose window is closed at once (batchToJoin). Walks stay one at
+// a time: such a batch is cut when no walk is open, and queued behind the one that is otherwise.
+//
 // A merge on the controller's own path (a module whose walk waits for nobody's word) never shares a batch with
 // one that waits for mesh-delivery's: each kind has a batch of its own, an own-path batch is cut first and folds
 // no waiting catalogue walk, and a catalogue walk let go while another walk runs starts once it ended — so no
@@ -173,6 +178,12 @@ func (f following) hearMerge(ctx context.Context, m link.SourceMoved, now time.T
 		fmt.Printf("%s merged into %s (%.8s); nothing the mesh holds reads it\n", repository, m.Base, m.Commit)
 		return nil
 	}
+	// **Its delivery group's word, before the plans are held** (ADR 0306 decision 2): a slow answer holds up no walk.
+	own := ownPath(touches)
+	waits, err := groupWait(ctx, inv, m, deliverySeatHeld(entries), own)
+	if err != nil {
+		return notNow(err)
+	}
 	release, err := inv.HoldPlans(ctx, true)
 	if err != nil {
 		return notNow(err)
@@ -198,7 +209,6 @@ func (f following) hearMerge(ctx context.Context, m link.SourceMoved, now time.T
 	// **A merge on the controller's own path never shares a batch with one that waits for the delivery's
 	// word** (decided during the build, 2026-10-10): batched together, the catalogue's deliveries would start
 	// with the controller's and skip their turn. Each kind has a batch of its own.
-	own := ownPath(touches)
 	if p, ok, err := answeredByALaterMerge(ctx, inv, heard, touches, own, deliverySeatHeld(entries)); err != nil {
 		return notNow(err)
 	} else if ok {
@@ -218,7 +228,7 @@ func (f following) hearMerge(ctx context.Context, m link.SourceMoved, now time.T
 		return cutBatchesHeld(ctx, f.open, now)
 	}
 
-	batch, err := theOpenBatch(ctx, inv, heard, now, own)
+	batch, why, err := batchToJoin(ctx, inv, heard, entries, read, now, own, waits)
 	if err != nil {
 		return notNow(err)
 	}
@@ -229,7 +239,7 @@ func (f following) hearMerge(ctx context.Context, m link.SourceMoved, now time.T
 	if err := keepBatch(ctx, inv, &batch, now, ""); err != nil {
 		return notNow(err)
 	}
-	fmt.Printf("%s merged into %s (%.8s); it joins %s — %s\n", repository, m.Base, m.Commit, batch.ID,
+	fmt.Printf("%s merged into %s (%.8s); %s, it joins %s — %s\n", repository, m.Base, m.Commit, why, batch.ID,
 		batchWords(batch, now))
 	return cutBatchesHeld(ctx, f.open, now)
 }
@@ -320,22 +330,211 @@ func ownPath(touches []inventory.Entry) bool {
 	return false
 }
 
-// theOpenBatch is the batch a merge heard now joins: the one of its kind not yet cut, or a new one.
-func theOpenBatch(ctx context.Context, inv *inventory.Inventory, first inventory.BatchedMerge, now time.Time, own bool) (inventory.Plan, error) {
+// **A merge waits only for a batch it shares something with** (novox/hq ADR 0304 decision 1, as ADR 0306
+// decisions 2 and 3 read it). batchToJoin is the batch a merge heard now joins, and why in words:
+//
+//   - an assembling or queued batch of its kind it is related to (related.go): it joins it and waits for the
+//     window, which its coming restarts. Related to two or more, the newer are folded into the oldest, which
+//     answers all their merges: a merge never waits in two windows, and what it shares with each walks in one.
+//   - none, and its delivery group has a member still to merge, or mesh-delivery could not say (groupWait, waits
+//     names why): a new batch, which waits for the window, beside the ones it shares nothing with; its words say
+//     why.
+//   - none, and no member of its group is still to merge: a new batch whose window is closed at once. Cut at
+//     once means only that: walks stay one at a time (ADR 0276 decision 4), so with a walk open the batch is
+//     queued behind it as any closed batch is.
+func batchToJoin(ctx context.Context, inv *inventory.Inventory, heard inventory.BatchedMerge, entries []inventory.Entry,
+	read map[string][]inventory.ReadRepository, now time.Time, own bool, waits string) (inventory.Plan, string, error) {
+	edges, err := inv.Dependencies(ctx)
+	if err != nil {
+		return inventory.Plan{}, "", err
+	}
+	joins, whys, _, err := relatedBatches(ctx, inv, []inventory.BatchedMerge{heard}, own, "", entries, read, edges)
+	if err != nil {
+		return inventory.Plan{}, "", err
+	}
+	if len(joins) > 0 {
+		into := joins[0]
+		why := "related to " + into.ID + " (" + whys[0] + ")"
+		if len(joins) > 1 {
+			plans, moves, err := foldInto(ctx, inv, &into, joins[1:])
+			if err != nil {
+				return inventory.Plan{}, "", err
+			}
+			if err := inv.SavePlansMoving(ctx, plans, moves); err != nil {
+				return inventory.Plan{}, "", err
+			}
+			var folded []string
+			for i, b := range joins[1:] {
+				folded = append(folded, b.ID+" ("+whys[i+1]+")")
+			}
+			why += ", and to " + strings.Join(folded, ", ") + ", folded into it"
+		}
+		into.Delivery.Batch.CutAtOnce = false
+		return into, why, nil
+	}
+	if waits != "" {
+		// Its own window, beside the batches it shares nothing with: waiting is for its group's members, which
+		// are related to it by their head and join it (ADR 0306 decision 2).
+		b, err := newBatch(ctx, inv, heard, now, own, false, waits)
+		return b, waits + ", it waits for the window in a batch of its own", err
+	}
+	b, err := newBatch(ctx, inv, heard, now, own, true, "")
+	return b, "it shares nothing with a batch assembling and no member of a group is still to merge: it is cut at once", err
+}
+
+// relatedBatches are the batches not yet cut of a kind, oldest first, parted into those related to merges (with
+// the first reason of each) and the others. Each batch is judged by what its cut would move (ADR 0306 decision
+// 3): its merges' moves as they were kept and as they read now — the catalogue may have moved since a merge was
+// heard — widened to their dependents, and, for a catalogue batch, every walk waiting for its word, which the
+// cut folds in (cutBatch's carry). A merge kept with no moves leaves its batch unknown, related to everything.
+// except is a walk not to count as folded: the one being stopped.
+func relatedBatches(ctx context.Context, inv *inventory.Inventory, merges []inventory.BatchedMerge, own bool,
+	except string, entries []inventory.Entry, read map[string][]inventory.ReadRepository,
+	edges []inventory.Edge) (joins []inventory.Plan, whys []string, others []inventory.Plan, err error) {
 	batches, err := inv.Batches(ctx)
 	if err != nil {
-		return inventory.Plan{}, err
+		return nil, nil, nil, err
 	}
+	var kind []inventory.Plan
 	for _, b := range batches {
 		if b.OwnPath() == own {
-			return b, nil
+			kind = append(kind, b)
 		}
 	}
+	if len(kind) == 0 {
+		return nil, nil, nil, nil
+	}
+	carry := newFootprint()
+	if !own {
+		// An own-path batch folds no waiting walk (cutBatchesHeld); a catalogue batch may fold every one.
+		plans, err := inv.OpenPlans(ctx)
+		if err != nil {
+			return nil, nil, nil, err
+		}
+		for _, p := range plans {
+			if p.Release != nil || !p.Waiting() || p.ID == except {
+				continue
+			}
+			kept, err := inv.MergesOf(ctx, p.ID)
+			if err != nil {
+				return nil, nil, nil, err
+			}
+			carry = unionFootprint(carry, footprintOfWalk(p, kept))
+		}
+	}
+	mine := footprintAsCut(merges, entries, read, edges)
+	for _, b := range kind {
+		held, err := inv.MergesOf(ctx, b.ID)
+		if err != nil {
+			return nil, nil, nil, err
+		}
+		if b.Delivery == nil {
+			b.Delivery = &inventory.PlanDelivery{}
+		}
+		if b.Delivery.Batch == nil {
+			b.Delivery.Batch = &inventory.PlanBatch{Own: own}
+		}
+		if ok, why := related(mine, unionFootprint(footprintAsCut(held, entries, read, edges), carry), edges); ok {
+			joins, whys = append(joins, b), append(whys, why)
+		} else {
+			others = append(others, b)
+		}
+	}
+	return joins, whys, others, nil
+}
+
+// footprintAsCut is a batch's footprint as a cut now would read it: footprintOfBatch, widened by the modules each
+// merge moves as the catalogue reads now (planBatch judges each merge again at the cut, so what it moves may
+// have changed since it was heard). Both are kept: when in doubt, related.
+func footprintAsCut(merges []inventory.BatchedMerge, entries []inventory.Entry,
+	read map[string][]inventory.ReadRepository, edges []inventory.Edge) footprint {
+	f := footprintOfBatch(merges, edges)
+	var moved []string
+	for _, m := range merges {
+		s := announcedOf(m).SourceMoved
+		if s.Owner == "" {
+			continue
+		}
+		s.MergedAt = "" // news, whatever a cut marked seen since (as planBatch reads it)
+		for _, e := range wouldMove(s, entries, read) {
+			moved = append(moved, e.Manifest.Module)
+		}
+	}
+	for _, name := range reachableFrom(moved, edges) {
+		f.modules[name] = true
+	}
+	return f
+}
+
+// unionFootprint is what two changes reach together.
+func unionFootprint(a, b footprint) footprint {
+	f := newFootprint()
+	for _, from := range []footprint{a, b} {
+		for k := range from.repos {
+			f.repos[k] = true
+		}
+		for k := range from.modules {
+			f.modules[k] = true
+		}
+		for k := range from.heads {
+			f.heads[k] = true
+		}
+	}
+	f.unknown = a.unknown
+	if f.unknown == "" {
+		f.unknown = b.unknown
+	}
+	return f
+}
+
+// foldInto folds batches into the oldest one related to a merge: the plans to write (into first, so no merge
+// names a plan the store does not hold) and the merges to move, for one SavePlansMoving. The folded batches name
+// the batch that took them over; a stop's closed window and its withheld modules (ADR 0299) go with their merges.
+func foldInto(ctx context.Context, inv *inventory.Inventory, into *inventory.Plan, from []inventory.Plan) ([]*inventory.Plan,
+	[]inventory.MergeMove, error) {
+	if into.Delivery == nil {
+		into.Delivery = &inventory.PlanDelivery{}
+	}
+	if into.Delivery.Batch == nil {
+		into.Delivery.Batch = &inventory.PlanBatch{Own: into.OwnPath()}
+	}
+	plans := []*inventory.Plan{into}
+	var moves []inventory.MergeMove
+	for i := range from {
+		f := from[i]
+		merges, err := inv.MergesOf(ctx, f.ID)
+		if err != nil {
+			return nil, nil, err
+		}
+		for _, m := range merges {
+			moves = append(moves, inventory.MergeMove{Repository: m.Repository, Commit: m.Commit, Plan: into.ID, Alone: m.Alone})
+		}
+		if f.Delivery == nil {
+			f.Delivery = &inventory.PlanDelivery{}
+		}
+		if w := f.Delivery.Batch; w != nil {
+			into.Delivery.Batch.Closed = into.Delivery.Batch.Closed || w.Closed
+			into.Delivery.Batch.Withheld = union(into.Delivery.Batch.Withheld, w.Withheld)
+			sort.Strings(into.Delivery.Batch.Withheld)
+		}
+		f.State = inventory.PlanSuperseded
+		f.Delivery.Batch = nil
+		f.Delivery.TakenOverBy = into.ID
+		f.Note = fmt.Sprintf("folded into %s before it was cut: a merge related to both joined it, and %s answers "+
+			"its merges", into.ID, into.ID)
+		plans = append(plans, &f)
+	}
+	return plans, moves, nil
+}
+
+// newBatch is a new batch of a kind, kept before its first merge names it: a merge never names a plan the store
+// does not hold. cutAtOnce closes its window at once; waits says why it waits for its group, when it does.
+func newBatch(ctx context.Context, inv *inventory.Inventory, first inventory.BatchedMerge, now time.Time, own,
+	cutAtOnce bool, waits string) (inventory.Plan, error) {
 	b := inventory.Plan{ID: fmt.Sprintf("plan-%d", now.UnixNano()), Repository: first.Repository, Branch: first.Branch,
 		Commit: first.Commit, Merged: first.Merged, Created: now, State: inventory.PlanAssembling,
 		Tiers: [][]string{}, Modules: map[string]*inventory.PlanModule{},
-		Delivery: &inventory.PlanDelivery{Batch: &inventory.PlanBatch{Own: own}}}
-	// Kept before its first merge names it: a merge never names a plan the store does not hold.
+		Delivery: &inventory.PlanDelivery{Batch: &inventory.PlanBatch{Own: own, CutAtOnce: cutAtOnce, Waits: waits}}}
 	if err := inv.SavePlan(ctx, &b); err != nil {
 		return inventory.Plan{}, err
 	}
@@ -367,13 +566,16 @@ func keepBatch(ctx context.Context, inv *inventory.Inventory, b *inventory.Plan,
 	}
 	closes, latest := windowOf(merges, b.Created, window, atMost)
 	b.Delivery.Merges = named
-	var closed bool
+	var closed, cutAtOnce bool
 	var withheld []string
+	var waits string
 	if was := b.Delivery.Batch; was != nil {
 		closed, withheld = was.Closed, was.Withheld // a stop's, which no look takes back (novox/hq ADR 0299)
+		cutAtOnce = was.CutAtOnce                   // the merge's, until another joins it (ADR 0304 decision 1)
+		waits = was.Waits                           // its group's, as said when it was made (ADR 0306 decision 2)
 	}
 	b.Delivery.Batch = &inventory.PlanBatch{ClosesAt: closes, AtMost: latest, Behind: behind, Own: b.OwnPath(),
-		Closed: closed, Withheld: withheld}
+		Closed: closed, Withheld: withheld, CutAtOnce: cutAtOnce, Waits: waits}
 	b.State = inventory.PlanAssembling
 	if behind != "" && windowClosed(*b, now) {
 		b.State = inventory.PlanQueued
@@ -402,13 +604,14 @@ func windowOf(merges []inventory.BatchedMerge, created time.Time, window, atMost
 	return last.Add(window), created.Add(atMost)
 }
 
-// windowClosed says a batch's window is closed: no merge for the window's length, or its maximum reached.
+// windowClosed says a batch's window is closed: closed by a stop, closed at once for a merge that shares
+// nothing (ADR 0304 decision 1), no merge for the window's length, or its maximum reached.
 func windowClosed(b inventory.Plan, now time.Time) bool {
 	if b.Delivery == nil || b.Delivery.Batch == nil {
 		return true
 	}
 	w := b.Delivery.Batch
-	return w.Closed || !now.Before(w.ClosesAt) || !now.Before(w.AtMost)
+	return w.Closed || w.CutAtOnce || !now.Before(w.ClosesAt) || !now.Before(w.AtMost)
 }
 
 // carriedOf is a set of merges as a walk carries them: the latest merge of each repository's branch, and
@@ -617,8 +820,9 @@ func cutBatchesHeld(ctx context.Context, open *stores, now time.Time) error {
 		return err
 	}
 	// The oldest batch whose window closed is cut, an own-path one before a catalogue one (it goes first, and
-	// the catalogue batch queues behind it rather than being cut and overtaken); one of each kind at most is
-	// open (theOpenBatch).
+	// the catalogue batch queues behind it rather than being cut and overtaken). Several of a kind may be open
+	// since a merge that shares nothing is cut at once (ADR 0304 decision 1): walks stay one at a time, so one
+	// is cut per look, and once its walk started the others are queued behind it.
 	sort.SliceStable(batches, func(i, j int) bool { return batches[i].OwnPath() && !batches[j].OwnPath() })
 	for i := range batches {
 		b := &batches[i]
@@ -886,6 +1090,9 @@ func walkTimesAtCut(batch, walk inventory.Plan, entries []inventory.Entry, now t
 		if !w.AtMost.IsZero() && w.AtMost.Before(closed) {
 			closed = w.AtMost
 		}
+		if w.CutAtOnce && !batch.Created.IsZero() {
+			closed = batch.Created // closed when it was made (ADR 0304 decision 1)
+		}
 		if !closed.IsZero() {
 			if closed.After(now) {
 				closed = now
@@ -902,6 +1109,16 @@ const resolverSeat = "mesh-dns-resolver"
 // classOf is a walk's class (novox/hq ADR 0282 decision 1): core when it walks a module on the controller's own
 // path or one holding the mesh's resolver, leaf otherwise.
 func classOf(walk inventory.Plan, entries []inventory.Entry) string {
+	modules := make([]string, 0, len(walk.Modules))
+	for m := range walk.Modules {
+		modules = append(modules, m)
+	}
+	return classOfModules(modules, entries)
+}
+
+// classOfModules is the class of modules moved together: core when one is on the controller's own path or holds
+// the mesh's resolver, leaf otherwise (ADR 0282 decision 1).
+func classOfModules(modules []string, entries []inventory.Entry) string {
 	resolvers := map[string]bool{}
 	for _, e := range entries {
 		for _, c := range e.Manifest.Claims {
@@ -910,7 +1127,7 @@ func classOf(walk inventory.Plan, entries []inventory.Entry) string {
 			}
 		}
 	}
-	for m := range walk.Modules {
+	for _, m := range modules {
 		if _, own := onTheControllersPath[m]; own || resolvers[m] {
 			return inventory.ClassCore
 		}
@@ -1142,6 +1359,10 @@ func batchWords(b inventory.Plan, now time.Time) string {
 	if b.State == inventory.PlanQueued {
 		return fmt.Sprintf("queued behind %s; grouped: %s; plan not yet calculated", w.Behind, grouped)
 	}
+	if w.CutAtOnce {
+		return fmt.Sprintf("cut at once, sharing nothing with a batch assembling; grouped: %s; plan not yet calculated",
+			grouped)
+	}
 	left := w.ClosesAt.Sub(now)
 	if w.AtMost.Before(w.ClosesAt) {
 		left = w.AtMost.Sub(now)
@@ -1149,8 +1370,12 @@ func batchWords(b inventory.Plan, now time.Time) string {
 	if left < 0 {
 		left = 0
 	}
-	return fmt.Sprintf("assembling: %s left (at the latest %s); grouped: %s; plan not yet calculated",
-		secondsWords(left), w.AtMost.Local().Format("15:04:05"), grouped)
+	waits := ""
+	if w.Waits != "" {
+		waits = " — " + w.Waits
+	}
+	return fmt.Sprintf("assembling: %s left (at the latest %s)%s; grouped: %s; plan not yet calculated",
+		secondsWords(left), w.AtMost.Local().Format("15:04:05"), waits, grouped)
 }
 
 // groupedWords is a batch's commits, each with the earlier merges it answers.

cmd/mesh-controller/batches_test.go

@@ -34,6 +34,7 @@ func windowed(t *testing.T) *stores {
 		t.Fatal(err)
 	}
 	t.Setenv(mergeWindowFileVar, settings)
+	noGroups(t)
 	if err := inv.RegisterModule(ctx, catalogue.Manifest{Module: "mesh-controller", Version: "1"},
 		inventory.Source{Repository: "novox/mesh-controller", Seat: "git", Ref: "main", BuiltFrom: "c0",
 			Head: "c0"}); err != nil {
@@ -58,19 +59,70 @@ func windowed(t *testing.T) *stores {
 // t0 is the moment a test's clock starts: merges are dated by it, and heard after it.
 var t0 = time.Now().UTC().Truncate(time.Second)
 
-// catalogueMerge is a merge of the catalogue changing one module's directory, made at a moment.
+// catalogueMerge is a merge of the catalogue changing one module's directory, made at a moment, from a pull
+// request's head branch of its own, as the forge announces every merge. Whether its head names a delivery group
+// with a member still to merge is mesh-delivery's word, which windowed stubs as no group at all (noGroups); a test
+// whose merges wait for the window as a group's says so (groupsWaiting).
 func catalogueMerge(commit, module string, made time.Time) link.SourceMoved {
-	return link.SourceMoved{Owner: "novox", Repo: "mesh-catalog", Base: "main", Commit: commit,
+	return link.SourceMoved{Owner: "novox", Repo: "mesh-catalog", Base: "main", Head: "pr/" + commit, Commit: commit,
 		MergedAt: made.Format(time.RFC3339Nano), Paths: []string{"modules/" + module + "/module.json"},
 		ModuleDirs: []string{"modules/" + module}, ModuleDirsSaid: true}
 }
 
-// repoMerge is a merge of a repository of one module's own.
+// repoMerge is a merge of a repository of one module's own, from a head branch of its own (catalogueMerge).
 func repoMerge(repo, commit string, made time.Time) link.SourceMoved {
-	return link.SourceMoved{Owner: "novox", Repo: repo, Base: "main", Commit: commit,
+	return link.SourceMoved{Owner: "novox", Repo: repo, Base: "main", Head: "pr/" + commit, Commit: commit,
 		MergedAt: made.Format(time.RFC3339Nano), Paths: []string{"main.go"}}
 }
 
+// noGroups stubs mesh-delivery's word on groups for a test: no head names a group.
+func noGroups(t *testing.T) {
+	t.Helper()
+	was := deliveryGroupOf
+	deliveryGroupOf = func(context.Context, bool, string) ([]groupMember, bool, error) { return nil, false, nil }
+	t.Cleanup(func() { deliveryGroupOf = was })
+}
+
+// groupsWaiting stubs mesh-delivery's word on groups for a test: each head named is a group with a member of another
+// repository whose pull request is open (novox/elsewhere, ready), so a merge from it waits for the window (ADR 0306
+// decision 2); every other head names no group.
+func groupsWaiting(t *testing.T, heads ...string) {
+	t.Helper()
+	was := deliveryGroupOf
+	deliveryGroupOf = func(_ context.Context, _ bool, head string) ([]groupMember, bool, error) {
+		if slices.Contains(heads, head) {
+			return []groupMember{{Repository: "novox/elsewhere", State: "ready"}}, true, nil
+		}
+		return nil, false, nil
+	}
+	t.Cleanup(func() { deliveryGroupOf = was })
+}
+
+// everyHeadWaits stubs mesh-delivery's word on groups for a test whose merges each wait for the window as they did
+// before novox/hq ADR 0304: every head is a group with a member of another repository still to merge.
+func everyHeadWaits(t *testing.T) {
+	t.Helper()
+	was := deliveryGroupOf
+	deliveryGroupOf = func(context.Context, bool, string) ([]groupMember, bool, error) {
+		return []groupMember{{Repository: "novox/elsewhere", State: "ready"}}, true, nil
+	}
+	t.Cleanup(func() { deliveryGroupOf = was })
+}
+
+// fromHead is a merge from a head branch a test names: merges from one head are members of one delivery group,
+// related by it (novox/hq ADR 0304 decision 1), so they share a batch whatever else they share.
+func fromHead(m link.SourceMoved, head string) link.SourceMoved {
+	m.Head = head
+	return m
+}
+
+// lone is a merge that names no head: known to be no delivery group's, it waits for no window unless it is
+// related to a batch assembling (ADR 0304 decision 1).
+func lone(m link.SourceMoved) link.SourceMoved {
+	m.Head = ""
+	return m
+}
+
 // hear is a merge heard at a moment.
 func hear(t *testing.T, open *stores, m link.SourceMoved, now time.Time) {
 	t.Helper()
@@ -108,6 +160,7 @@ func walks(t *testing.T, open *stores) (walks, batches []inventory.Plan) {
 // later commit, which names both merges — the earlier carried by the later.
 func TestTwoMergesSecondsApartAreOneWalkAtTheLaterCommit(t *testing.T) {
 	open := windowed(t)
+	everyHeadWaits(t)
 	asked := asksWithPaths(t)
 	claude := catalogueMerge("553b7191claude", "app", t0)
 	dunst := catalogueMerge("48bda475dunst", "notes", t0.Add(17*time.Second))
@@ -152,9 +205,10 @@ func TestTwoMergesSecondsApartAreOneWalkAtTheLaterCommit(t *testing.T) {
 // Merges of three repositories in one window are one walk, one commit for each.
 func TestThreeRepositoriesInOneWindowAreOneWalk(t *testing.T) {
 	open := windowed(t)
+	groupsWaiting(t, "feat/three")
 	asksRecorded(t)
 	for i, r := range []string{"one", "two", "three"} {
-		hear(t, open, repoMerge(r, "c-"+r, t0.Add(time.Duration(i)*20*time.Second)),
+		hear(t, open, fromHead(repoMerge(r, "c-"+r, t0.Add(time.Duration(i)*20*time.Second)), "feat/three"),
 			t0.Add(time.Duration(i)*20*time.Second+time.Second))
 	}
 	cutAt(t, open, t0.Add(41*time.Second+90*time.Second))
@@ -187,9 +241,10 @@ func TestThreeRepositoriesInOneWindowAreOneWalk(t *testing.T) {
 // closes at most ten minutes after its first merge however busy.
 func TestAMergeRestartsTheWindowAndTheMaximumClosesIt(t *testing.T) {
 	open := windowed(t)
+	groupsWaiting(t, "feat/both", "feat/busy")
 	asksWithPaths(t)
-	hear(t, open, repoMerge("one", "c1", t0), t0)
-	hear(t, open, repoMerge("two", "c2", t0.Add(80*time.Second)), t0.Add(80*time.Second))
+	hear(t, open, fromHead(repoMerge("one", "c1", t0), "feat/both"), t0)
+	hear(t, open, fromHead(repoMerge("two", "c2", t0.Add(80*time.Second)), "feat/both"), t0.Add(80*time.Second))
 	cutAt(t, open, t0.Add(100*time.Second))
 	if ws, _ := walks(t, open); len(ws) != 0 {
 		t.Fatal("the window closed 90 seconds after its first merge, not after its last")
@@ -200,12 +255,13 @@ func TestAMergeRestartsTheWindowAndTheMaximumClosesIt(t *testing.T) {
 	}
 
 	busy := windowed(t)
+	groupsWaiting(t, "feat/both", "feat/busy")
 	asksWithPaths(t)
 	var last time.Time
 	for i := 0; i < 12; i++ {
 		last = t0.Add(time.Duration(i) * time.Minute)
 		repo := []string{"one", "two", "three"}[i%3]
-		hear(t, busy, repoMerge(repo, "c"+string(rune('a'+i)), last), last)
+		hear(t, busy, fromHead(repoMerge(repo, "c"+string(rune('a'+i)), last), "feat/busy"), last)
 		if ws, _ := walks(t, busy); len(ws) > 0 {
 			if i != 10 {
 				t.Fatalf("a busy window closed at merge %d (minute %d), not at its maximum", i, i)
@@ -223,10 +279,11 @@ func TestAMergeRestartsTheWindowAndTheMaximumClosesIt(t *testing.T) {
 // what is grouped, and that the plan is not yet calculated. It says so on the bus as plan-moved, too.
 func TestTheAssemblingBatchIsShown(t *testing.T) {
 	open := windowed(t)
+	groupsWaiting(t, "pr/553b7191claude")
 	asksWithPaths(t)
 	var said []inventory.Plan
 	was := inventory.PlanSaved
-	inventory.PlanSaved = func(p inventory.Plan) { said = append(said, p) }
+	inventory.PlanSaved = func(_ *inventory.Inventory, p inventory.Plan) { said = append(said, p) }
 	t.Cleanup(func() { inventory.PlanSaved = was })
 	now := time.Now().UTC()
 	claude := catalogueMerge("553b7191claude", "app", now.Add(-20*time.Second))
@@ -235,7 +292,7 @@ func TestTheAssemblingBatchIsShown(t *testing.T) {
 	dunst.Number, dunst.Title = 175, "dunst: the font the operator chose"
 	hear(t, open, claude, now.Add(-19*time.Second))
 	hear(t, open, dunst, now.Add(-time.Second))
-	hear(t, open, repoMerge("one", "a6bc0931one", now), now)
+	hear(t, open, fromHead(repoMerge("one", "a6bc0931one", now), dunst.Head), now)
 	out := captured(t, func() error { return plansCommand(t.Context(), nil) })
 	lines := strings.Split(out, "\n")
 	first := lines[0]
@@ -360,6 +417,7 @@ func TestAWaitingWalkIsFoldedIntoTheNextBatch(t *testing.T) {
 // moves — named at once on a walk done — and joins the next batch when it does not.
 func TestALateMergeIsAnsweredByTheWalkOfTheLaterOne(t *testing.T) {
 	open := windowed(t)
+	everyHeadWaits(t)
 	asksWithPaths(t)
 	ctx := t.Context()
 	later := catalogueMerge("48bda475dunst", "notes", t0.Add(17*time.Second))
@@ -391,6 +449,7 @@ func TestALateMergeIsAnsweredByTheWalkOfTheLaterOne(t *testing.T) {
 // first; the first delivered answers the older ones, and the search stops.
 func TestAFailedWalkWalksItsEarlierMergesAlone(t *testing.T) {
 	open := windowed(t)
+	everyHeadWaits(t)
 	asked := asksWithPaths(t)
 	ctx := t.Context()
 	// Made before the cut marks their modules seen, as merges are: walked again, they are news all the same.
@@ -459,6 +518,7 @@ func TestAFailedWalkWalksItsEarlierMergesAlone(t *testing.T) {
 func TestAGroupsOrderBecomesTiersInsideTheWalk(t *testing.T) {
 	for _, grouped := range []bool{true, false} {
 		open := windowed(t)
+		everyHeadWaits(t)
 		asksWithPaths(t)
 		ctx := t.Context()
 		for _, m := range []string{"mesh-host"} {
@@ -496,9 +556,10 @@ func TestAGroupsOrderBecomesTiersInsideTheWalk(t *testing.T) {
 // store, a merge handed over again is not doubled, and the batch is cut when its window closes.
 func TestABatchSurvivesARestart(t *testing.T) {
 	open := windowed(t)
+	groupsWaiting(t, "feat/both")
 	asksWithPaths(t)
-	hear(t, open, repoMerge("one", "c1", t0), t0)
-	hear(t, open, repoMerge("two", "c2", t0.Add(30*time.Second)), t0.Add(30*time.Second))
+	hear(t, open, fromHead(repoMerge("one", "c1", t0), "feat/both"), t0)
+	hear(t, open, fromHead(repoMerge("two", "c2", t0.Add(30*time.Second)), "feat/both"), t0.Add(30*time.Second))
 
 	// A new controller: nothing of the first one's but the store.
 	again, err := openStores(t.Context())
@@ -506,7 +567,7 @@ func TestABatchSurvivesARestart(t *testing.T) {
 		t.Fatal(err)
 	}
 	t.Cleanup(again.Close)
-	hear(t, again, repoMerge("one", "c1", t0), t0.Add(60*time.Second)) // the bus hands it over again
+	hear(t, again, fromHead(repoMerge("one", "c1", t0), "feat/both"), t0.Add(60*time.Second)) // the bus hands it over again
 	cutAt(t, again, t0.Add(119*time.Second))
 	if ws, bs := walks(t, again); len(ws) != 0 || len(bs) != 1 || len(bs[0].Delivery.Merges) != 2 {
 		t.Fatalf("the restarted controller's batch: %d walk(s), %+v", len(ws), bs)
@@ -563,6 +624,7 @@ func TestAWaitingWalkNamesTheMergesItAnswers(t *testing.T) {
 // nothing, and the merge joins the next batch.
 func TestALateMergeOfAOneModuleRepositoryIsNamed(t *testing.T) {
 	open := windowed(t)
+	everyHeadWaits(t)
 	asksWithPaths(t)
 	ctx := t.Context()
 	c2 := repoMerge("one", "c2", t0.Add(-50*time.Second))
@@ -716,6 +778,7 @@ func TestTheCatchUpKeepsWhatACutMadeHistory(t *testing.T) {
 // still waits for the word, so no catalogue delivery skips its turn.
 func TestAMergeOnTheControllersPathNeverSharesABatch(t *testing.T) {
 	open := windowed(t)
+	everyHeadWaits(t)
 	asked := asksWithPaths(t)
 	ctx := t.Context()
 	if err := open.inventory.RegisterModule(ctx, catalogue.Manifest{Module: "mesh-delivery", Version: "1",
@@ -860,6 +923,7 @@ func sameMerge(a, b inventory.PlanMerge) bool {
 // its delivery would skip its turn. It joins the next catalogue batch.
 func TestALateCatalogueMergeIsNotAnsweredByAnOwnPathWalk(t *testing.T) {
 	open := windowed(t)
+	everyHeadWaits(t)
 	asksWithPaths(t)
 	ctx := t.Context()
 	for _, m := range []struct {

cmd/mesh-controller/batches_watch.go

@@ -48,6 +48,10 @@ func gatherBatches(ctx context.Context, inv *inventory.Inventory, now time.Time)
 			if f.atMost.Before(f.closed) {
 				f.closed = f.atMost
 			}
+			if w.Batch.CutAtOnce && !b.Created.IsZero() {
+				// Its window closed when it was made, which is its latest too (ADR 0304 decision 1).
+				f.atMost, f.closed = b.Created, b.Created
+			}
 		}
 		if f.behind != "" {
 			if walk, err := inv.PlanByID(ctx, f.behind); err == nil {

cmd/mesh-controller/changeplan.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"fmt"
+	"path"
 	"slices"
 	"sort"
 	"strings"
@@ -105,9 +106,32 @@ func changePlanOf(repository, base, head string, r mergeReach, entries []invento
 		p.Machines = append(p.Machines, *machines[name])
 	}
 	p.Summary = summaryOf(p)
+	p.Class = changeClassOf(p, entries)
 	return p
 }
 
+// classNone is the class of a change that moves no module: nothing for a walk to move (novox/hq ADR 0313 §2).
+const classNone = "none"
+
+// changeClassOf is a change plan's class (novox/hq ADR 0313 §2): that of the slowest-budgeted module it moves,
+// itself or as a dependent — core when one is on the controller's own path or holds the mesh's resolver, leaf
+// otherwise — and none when it moves nothing. A module it adds a directory for counts by its own class: the
+// catalogue names a module's directory by the module, so the directory's last element is its name. The graph holds
+// no manifest of it yet, so a new module is core by its name alone (on the controller's own path), never by a
+// resolver claim its manifest makes.
+func changeClassOf(p link.ChangePlan, entries []inventory.Entry) string {
+	if len(p.Moved) == 0 && len(p.Dependents) == 0 && len(p.New) == 0 {
+		return classNone
+	}
+	modules := append(append([]string{}, p.Moved...), p.Dependents...)
+	for _, dir := range p.New {
+		if name := path.Base(strings.Trim(dir, "/")); name != "." && name != "/" && name != "" {
+			modules = append(modules, name)
+		}
+	}
+	return classOfModules(modules, entries)
+}
+
 // grantsStepWord names the grants step (novox/hq issue 490): the bus's user list sent alone to the machine
 // holding the bus ahead of a walk's gate. Not the bus step, which replaces the bus itself.
 const grantsStepWord = "grants step"

cmd/mesh-controller/checks.go

@@ -161,9 +161,7 @@ func (f following) PullUpdated(ctx context.Context, p link.PullUpdated) error {
 		return u, err == nil
 	})
 	fmt.Print(planText(plan))
-	direct := link.Checked{Owner: p.Owner, Repo: p.Repo, Number: p.Number, Commit: p.Commit,
-		ID: link.NewBuildID(time.Now()), Verdict: "pass", Summary: noModuleTouched,
-		Gate: &link.CheckLayer{Verdict: "pass", Summary: noModuleTouched}, Plan: &plan}
+	direct := directVerdict(p, plan)
 	switch {
 	case !scope.gated() && !scope.Mesh:
 		fmt.Printf("%s/%s#%d (%.8s): %s, and the repository is not the mesh's: said, nothing run\n",
@@ -201,6 +199,24 @@ func (f following) PullUpdated(ctx context.Context, p link.PullUpdated) error {
 	return nil
 }
 
+// directVerdict is the verdict of a change no build judges — it touches no module, and either the repository is not
+// the mesh's or the head holds no merge-check.sh. **It names the trunk commit it holds for** (novox/hq ADR 0323 §3):
+// the base branch's head the forge announced with the head, so the merge tool can weigh it against the trunk's head
+// and does not refuse it for ever (a verdict naming no trunk is never the trunk's head's). Nothing was built to
+// judge: the trunk commit is the one the forge said the change was announced against.
+func directVerdict(p link.PullUpdated, plan link.ChangePlan) link.Checked {
+	trunk := p.BaseSHA
+	if len(trunk) > 12 {
+		trunk = trunk[:12]
+	}
+	if trunk != "" {
+		plan.Trunk = trunk
+	}
+	return link.Checked{Owner: p.Owner, Repo: p.Repo, Number: p.Number, Commit: p.Commit,
+		ID: link.NewBuildID(time.Now()), Verdict: "pass", Summary: noModuleTouched,
+		Gate: &link.CheckLayer{Verdict: "pass", Summary: noModuleTouched}, Plan: &plan, Trunk: trunk}
+}
+
 // checkRequestFor is the ask for one pull request's head: the repository as the mesh clones it, the head,
 // and what is read beside it.
 func checkRequestFor(ctx context.Context, open *stores, p link.PullUpdated, scope checkScope,
@@ -363,6 +379,9 @@ func checkedOf(result link.BuildResult) link.Checked {
 	case result.Check != nil:
 		c.Verdict, c.Summary, c.Report = result.Check.Verdict, result.Check.Summary, result.Check.Report
 		c.Gate, c.RepoCheck = result.Check.Gate, result.Check.RepoCheck
+		// What was judged (novox/hq ADR 0323 §3): the head merged into the trunk commit, and the commits of the
+		// repositories read beside it.
+		c.Trunk, c.Beside, c.Took = result.Check.Trunk, result.Check.Beside, result.Check.Took
 		if c.Gate == nil {
 			// A build seat from before the layers: its verdict is the gate's.
 			c.Gate = &link.CheckLayer{Verdict: c.Verdict, Summary: c.Summary}
@@ -388,14 +407,20 @@ func checkedOf(result link.BuildResult) link.Checked {
 	}
 	if result.Checked != nil {
 		c.Plan = result.Checked.Plan
+		if c.Plan != nil && c.Trunk != "" {
+			// The kept delivery plan records the trunk commit with its other inputs (ADR 0323 §3).
+			plan := *c.Plan
+			plan.Trunk = c.Trunk
+			c.Plan = &plan
+		}
 		// A delivery group's composed check (novox/hq ADR 0239): every head it judged, this one first.
 		if g := result.Checked; g.Group != "" {
 			c.Group = g.Group
 			c.Members = append(c.Members, link.CheckedMember{Owner: g.Owner, Repo: g.Repo, Number: g.Number,
-				Commit: result.Ref})
+				Commit: result.Ref, Trunk: c.Trunk})
 			for _, m := range g.Members {
 				c.Members = append(c.Members, link.CheckedMember{Owner: m.Owner, Repo: m.Repo, Number: m.Number,
-					Commit: m.Ref})
+					Commit: m.Ref, Trunk: memberTrunk(result.Check, m)})
 			}
 		}
 	}
@@ -410,6 +435,20 @@ func checkedOf(result link.BuildResult) link.Checked {
 	return c
 }
 
+// memberTrunk is the trunk commit the build seat merged one of a group's heads into (novox/hq ADR 0323 §6), empty
+// when it said none.
+func memberTrunk(outcome *link.CheckOutcome, m link.GroupMember) string {
+	if outcome == nil {
+		return ""
+	}
+	for _, j := range outcome.Members {
+		if strings.EqualFold(j.Owner, m.Owner) && strings.EqualFold(j.Repo, m.Repo) && strings.HasPrefix(m.Ref, j.Commit) {
+			return j.Trunk
+		}
+	}
+	return ""
+}
+
 func prefixedAll(prefix string, items []string) []string {
 	out := make([]string, 0, len(items))
 	for _, i := range items {
@@ -424,8 +463,12 @@ func sayChecked(ctx context.Context, c link.Checked) {
 	if c.RepoCheck != nil {
 		repo = strings.ToUpper(c.RepoCheck.Verdict) + " — " + c.RepoCheck.Summary
 	}
-	fmt.Printf("%s: %s/%s#%d at %.8s checked on %s: gate %s — %s; repository %s\n", c.ID, c.Owner, c.Repo, c.Number,
-		c.Commit, orSomewhere(c.On), strings.ToUpper(c.Verdict), c.Summary, repo)
+	judged := ""
+	if c.Trunk != "" {
+		judged = " merged into trunk " + c.Trunk
+	}
+	fmt.Printf("%s: %s/%s#%d at %.8s%s checked on %s: gate %s — %s; repository %s\n", c.ID, c.Owner, c.Repo, c.Number,
+		c.Commit, judged, orSomewhere(c.On), strings.ToUpper(c.Verdict), c.Summary, repo)
 	if checkEvents == nil {
 		return
 	}

cmd/mesh-controller/checks_test.go

@@ -210,3 +210,81 @@ func TestABuildOffTheTrunkIsNeverPublished(t *testing.T) {
 		t.Errorf("a build seat that said nothing was refused: %v", err)
 	}
 }
+
+// **A verdict names the trunk commit it judged** (novox/hq ADR 0323 §3, issue 341): the controller's `checked`
+// carries the head and the trunk commit the build seat merged it into, the commits of the repositories read beside
+// it, how long it took, and the kept delivery plan records the trunk commit with its other inputs. A group's
+// composed check names, per member, the trunk commit that head was merged into (§6).
+func TestAVerdictNamesTheTrunkCommitItJudged(t *testing.T) {
+	plan := &link.ChangePlan{Repository: "novox/mesh-host", Base: "main", Head: "dfb1415aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
+		Summary: "builds mesh-host"}
+	asked := &link.CheckRequest{Owner: "novox", Repo: "mesh-host", Number: 66, Base: "main", Plan: plan}
+	c := checkedOf(link.BuildResult{ID: "b", Ref: "dfb1415aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa", Checked: asked,
+		Check: &link.CheckOutcome{Verdict: "pass", Took: "4m12s", Head: "dfb1415aaaaa", Trunk: "d28ca95bbbbb",
+			Gate: &link.CheckLayer{Verdict: "pass"}, RepoCheck: &link.CheckLayer{Verdict: "pass"},
+			Beside: map[string]string{"mesh-catalog": "0123456789ab", "mesh-lab": "ba9876543210"}}})
+	if c.Trunk != "d28ca95bbbbb" || c.Commit != "dfb1415aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa" {
+		t.Fatalf("the verdict names head %s and trunk %q", c.Commit, c.Trunk)
+	}
+	if c.Beside["mesh-catalog"] != "0123456789ab" || c.Beside["mesh-lab"] != "ba9876543210" {
+		t.Fatalf("the verdict names the repositories read beside it as %v", c.Beside)
+	}
+	if c.Took != "4m12s" {
+		t.Fatalf("the verdict says it took %q", c.Took)
+	}
+	if c.Plan == nil || c.Plan.Trunk != "d28ca95bbbbb" || c.Plan.Head != plan.Head {
+		t.Fatalf("the kept plan records %+v", c.Plan)
+	}
+	if plan.Trunk != "" {
+		t.Fatal("the plan the controller asked with was changed: the verdict's is a copy")
+	}
+
+	group := &link.CheckRequest{Owner: "novox", Repo: "mesh-controller", Number: 7, Base: "main", Group: "feat/x",
+		Members: []link.GroupMember{{Owner: "novox", Repo: "mesh-host", Number: 8, Ref: "cccccccccccc0000", Base: "main"}}}
+	c = checkedOf(link.BuildResult{ID: "g", Ref: "aaaaaaaaaaaa0000", Checked: group, Check: &link.CheckOutcome{
+		Verdict: "pass", Head: "aaaaaaaaaaaa", Trunk: "111111111111", Gate: &link.CheckLayer{Verdict: "pass"},
+		Members: []link.CheckedMember{{Owner: "novox", Repo: "mesh-host", Commit: "cccccccccccc", Trunk: "222222222222"}}}})
+	if len(c.Members) != 2 || c.Members[0].Trunk != "111111111111" || c.Members[1].Trunk != "222222222222" ||
+		c.Members[1].Commit != "cccccccccccc0000" {
+		t.Fatalf("the composed check names its members %+v", c.Members)
+	}
+}
+
+// **The merge made for a check is never registered** (novox/hq ADR 0323 §2): a build of it — a commit on no branch
+// of the forge — is refused, naming the trunk. The rule of ADR 0238 §1 stands unchanged; this holds it for the
+// merge commit a check makes.
+func TestABuildOfACheckMergeIsRefusedNamingTheTrunk(t *testing.T) {
+	merge := link.BuildResult{ID: "b", Commit: "4b5c6d7e8f90aabbccddeeff0011223344556677", Trunk: "main"}
+	err := publishable(merge, "")
+	if !errors.Is(err, errOffTheTrunk) || !strings.Contains(err.Error(), "not on main") {
+		t.Fatalf("a build of a check's merge was answered %v", err)
+	}
+}
+
+// **A verdict no build judges names its trunk commit too** (novox/hq ADR 0323 §3): a change touching no module of a
+// repository with no merge-check.sh (novox/mesh-tools-go) is answered by the controller itself. Naming no trunk, the
+// merge tool refused it, asked again, got the same verdict, and refused for ever.
+func TestADirectVerdictNamesTheTrunkTheForgeAnnounced(t *testing.T) {
+	p := link.PullUpdated{Owner: "novox", Repo: "mesh-tools-go", Number: 3, Base: "main", Commit: "1a2b3c4d5e6f7a8b9c0d",
+		BaseSHA: "7a8b9c0d1e2f3a4b5c6d7e8f9a0b1c2d3e4f5a6b"}
+	c := directVerdict(p, link.ChangePlan{Repository: "novox/mesh-tools-go", Base: "main", Head: p.Commit})
+	if c.Trunk != "7a8b9c0d1e2f" || c.Plan == nil || c.Plan.Trunk != "7a8b9c0d1e2f" {
+		t.Fatalf("the direct verdict names trunk %q, its plan %+v", c.Trunk, c.Plan)
+	}
+	if c.Verdict != "pass" || c.Commit != p.Commit {
+		t.Fatalf("the direct verdict is %+v", c)
+	}
+	if c := directVerdict(link.PullUpdated{Owner: "novox", Repo: "x", Commit: "abc"}, link.ChangePlan{}); c.Trunk != "" {
+		t.Fatalf("a forge that said no base head gave the trunk %q", c.Trunk)
+	}
+}
+
+// A head checked again through mesh-delivery (`delivery check --members`, a recheck) reaches the same direct verdict:
+// it names the base head the forge last announced, kept on the member, or the merge tool would refuse it for ever.
+func TestARecheckedHeadsDirectVerdictNamesItsTrunk(t *testing.T) {
+	m := orderMember{ID: "novox/mesh-tools-go@1a2b3c4d5e6f", Repository: "novox/mesh-tools-go", Base: "main",
+		Head: "1a2b3c4d5e6f7a8b9c0d", Number: 3, BaseSHA: "7a8b9c0d1e2f3a4b5c6d7e8f9a0b1c2d3e4f5a6b"}
+	if c := directVerdict(m.pull(), link.ChangePlan{}); c.Trunk != "7a8b9c0d1e2f" {
+		t.Fatalf("a rechecked head's direct verdict names trunk %q", c.Trunk)
+	}
+}

cmd/mesh-controller/core_downgrade.go

@@ -0,0 +1,215 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"sort"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/lease"
+)
+
+// **No send but a person's `push <node>` and a gate's own put-back moves the mesh's own core to a build older
+// than the one its machine was last sent** (novox/hq issue 201). Every send made through sendToEach keeps it — a
+// plan's, a release's, a healer's, a rotation's, and the bus step too, which is a person's act but composes under
+// sendKeeps like the rest. On 2026-10-02 two merges a minute apart made two plans;
+// the controller's plan rolled the new controller, which widened its seat's row, and the node-engine's plan then
+// sent the control node the controller build before it. The older binary read the row it could not serve and the
+// mesh lost its voice for ten minutes — the thing that would have corrected it was the thing that was down. ADR
+// 0185 took the outage out of it (a controller behind its row serves what it can); the race is closed here,
+// without needing its trigger: whatever made the mesh's record older, the send keeps the build.
+//
+// **Kept, not refused.** The send composes the controller or the node-engine at the build the machine was last
+// sent, as a recorded module is kept (ADR 0245), and carries everything else: no other module, secret, healer or
+// walk waits on it, and nothing is retried. The kept move is no move for a gate either: ungatedIn and gatedSend
+// leave it out (withoutKept), so a gate judges the other moves of its send. A plan whose own build is the older one finds its gate superseded by
+// the build kept there (issue 352) and ends. The mesh's record stays older, and a warning condition says so until
+// a send carries the record — a person's `push <node>` accepts the older build — or the record moves forward: a
+// newer merge, or `rebuild mesh-controller`.
+//
+// Older is by the builds' registration order — when each was asked (novox/hq issue 219) — never by the commits'
+// dates. So a retry or a rebuild of an old commit, asked anew, counts as newer: it is registered as the module's
+// current build by the same order, and the guard does not stop that move. A build that failed its gate is never
+// ahead: the machine was sent it and the record was put back before it (gateFailed), and if the put-back's own
+// send was refused, the next send completes it rather than keeping the failed build there. A gate's own put-back
+// carries its modules back whatever the order (sendScope.puttingBack); the controller's is held to the store's
+// schema already (issue 352).
+
+// kindCoreDowngrade is a core module kept at the build its machine was last sent, over an older record.
+const kindCoreDowngrade = "core-downgrade-kept"
+
+// coreDowngradeSource is the condition's source: the sends, which raise and clear it.
+const coreDowngradeSource = "sends"
+
+// downgradeGuarded is the core components a send may not move backwards: the controller, which reads the
+// store and its seat's row, and the node-engine, which reads what the controller declares.
+var downgradeGuarded = []string{lease.ComponentController, lease.ComponentEngine}
+
+// askedBuild is what the order needs of one build of a module: when it was asked, and whether it failed its gate.
+type askedBuild struct {
+	asked      time.Time
+	failedGate bool
+}
+
+// buildAsked is the newest build of a module from a commit that worked — when it was asked (or recorded, when
+// the request time is not known), and whether it failed its gate — and false when the records hold none. A
+// variable, so a test reads its own order.
+var buildAsked = func(ctx context.Context, inv *inventory.Inventory, module, commit string) (askedBuild, bool, error) {
+	builds, err := inv.Builds(ctx, module, askedLookBack)
+	if err != nil {
+		return askedBuild{}, false, err
+	}
+	for _, b := range builds {
+		if b.Worked() && sameCommit(b.Commit, commit) {
+			failed, err := inv.GateFailed(ctx, b.ID)
+			if err != nil {
+				return askedBuild{}, false, err
+			}
+			return askedBuild{asked: b.AskedOrAt(), failedGate: failed}, true, nil
+		}
+	}
+	return askedBuild{}, false, nil
+}
+
+// askedLookBack is how many of a module's newest builds are read for when a build was asked.
+const askedLookBack = 50
+
+// coreDowngrade is one core module a machine was last sent a build of that is newer than the mesh's record.
+type coreDowngrade struct {
+	module, node, component string
+	// sent is the build the machine was last sent, record the one the mesh holds.
+	sent, record           string
+	sentAsked, recordAsked time.Time
+}
+
+func (d coreDowngrade) String() string {
+	return fmt.Sprintf("%s was last sent %s %s, and the mesh holds the older %s (asked %s, before %s): a send there "+
+		"keeps %s; `push %s` sends the older build, and a newer merge or `rebuild %s` moves the record forward "+
+		"(novox/hq issue 201)", d.node, d.module, short(d.sent), short(d.record),
+		d.recordAsked.UTC().Format(time.RFC3339), d.sentAsked.UTC().Format(time.RFC3339), short(d.sent), d.node,
+		d.module)
+}
+
+// coreDowngrades is, for one machine, each guarded core module whose record is older than the build the machine
+// was last sent, leaving out what a gate's own put-back puts back and a sent build that failed its gate. A move
+// whose either build the records do not hold is not proved older and is left to the gate that judges it. Pure
+// but for asked.
+func coreDowngrades(node string, sent map[string]string, record map[string]string, scope sendScope,
+	asked func(module, commit string) (askedBuild, bool, error)) ([]coreDowngrade, error) {
+	var out []coreDowngrade
+	for module, was := range sent {
+		component := coreComponent(module)
+		now := record[module]
+		if !guarded(component) || was == "" || now == "" || sameCommit(was, now) {
+			continue
+		}
+		if scope.puttingBack && scope.modules[module] {
+			continue
+		}
+		from, known, err := asked(module, was)
+		if err != nil {
+			return nil, fmt.Errorf("when %s's build %s was asked cannot be read: %w", module, short(was), err)
+		}
+		if !known || from.failedGate {
+			continue
+		}
+		to, known, err := asked(module, now)
+		if err != nil {
+			return nil, fmt.Errorf("when %s's build %s was asked cannot be read: %w", module, short(now), err)
+		}
+		if known && to.asked.Before(from.asked) {
+			out = append(out, coreDowngrade{module: module, node: node, component: component, sent: was, record: now,
+				sentAsked: from.asked, recordAsked: to.asked})
+		}
+	}
+	sort.Slice(out, func(i, j int) bool { return out[i].module < out[j].module })
+	return out, nil
+}
+
+func guarded(component string) bool {
+	for _, c := range downgradeGuarded {
+		if c == component {
+			return true
+		}
+	}
+	return false
+}
+
+// coreKept is, for a send that keeps (sendKeeps), each guarded core module of a machine to keep at the build it
+// was last sent, module → commit, each said and raised as a condition.
+func coreKept(ctx context.Context, inv *inventory.Inventory, node string, sent map[string]string,
+	current map[string]inventory.CurrentBuild) (map[string]string, error) {
+	record := map[string]string{}
+	for m, c := range current {
+		record[m] = c.Commit
+	}
+	found, err := coreDowngrades(node, sent, record, scopeOf(ctx), func(module, commit string) (askedBuild, bool, error) {
+		return buildAsked(ctx, inv, module, commit)
+	})
+	if err != nil || len(found) == 0 {
+		return nil, err
+	}
+	out := map[string]string{}
+	for _, d := range found {
+		out[d.module] = d.sent
+		sayCoreDowngrade(ctx, d)
+	}
+	return out, nil
+}
+
+// coreDowngradeObservation is a kept core build as a condition: `core.<component>.<machine>.<kind>`.
+func coreDowngradeObservation(component, node, summary string) conditions.Observation {
+	return conditions.Observation{Scope: conditions.ScopeCore, ID: component + "." + node, Kind: kindCoreDowngrade,
+		Token: kindCoreDowngrade, Machine: node, Severity: conditions.Warning, Source: coreDowngradeSource,
+		Summary: summary}
+}
+
+func sayCoreDowngrade(ctx context.Context, d coreDowngrade) {
+	fmt.Printf("KEPT: %s\n", d)
+	keeper := conditionsFrom
+	if keeper == nil {
+		return
+	}
+	if _, err := keeper.Observe(ctx, coreDowngradeObservation(d.component, d.node, d.String())); err != nil {
+		fmt.Printf("the condition for %s kept on %s could not be raised: %v\n", d.module, d.node, err)
+	}
+}
+
+// settleCoreDowngrades clears, after a send to a machine is away, the condition of each guarded core module the
+// send carried at the mesh's record — a person's push that accepted the older build, or a send after the record
+// moved forward — or did not carry at all. A send that kept the newer build leaves it open.
+func settleCoreDowngrades(ctx context.Context, inv *inventory.Inventory, node string, carried map[string]string) {
+	keeper := conditionsFrom
+	if keeper == nil || carried == nil {
+		return
+	}
+	var open []string
+	for _, c := range downgradeGuarded {
+		if _, found, err := keeper.Get(ctx, coreDowngradeObservation(c, node, "").Key()); err == nil && found {
+			open = append(open, c)
+		}
+	}
+	if len(open) == 0 {
+		return
+	}
+	current, err := inv.CurrentBuilds(ctx)
+	if err != nil {
+		fmt.Printf("whether %s still keeps a core build over the mesh's record cannot be read: %v\n", node, err)
+		return
+	}
+	for module, now := range current {
+		component := coreComponent(module)
+		if !guarded(component) {
+			continue
+		}
+		if was, has := carried[module]; has && !sameCommit(was, now.Commit) {
+			continue
+		}
+		key := coreDowngradeObservation(component, node, "").Key()
+		if _, err := keeper.Clear(ctx, key, node+" was sent the "+component+" the mesh holds"); err != nil {
+			fmt.Printf("the condition %s could not be cleared: %v\n", key, err)
+		}
+	}
+}

cmd/mesh-controller/delivery.go

@@ -10,6 +10,7 @@ import (
 	"slices"
 	"sort"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/nats-io/nats.go"
@@ -240,7 +241,7 @@ func stopWalkWithout(ctx context.Context, inv *inventory.Inventory, id, by, why
 		}
 		return p, said, inv.SavePlan(ctx, &p)
 	}
-	target, err := batchToWalkAgain(ctx, inv, again, now)
+	target, folded, foldMoves, err := batchToWalkAgain(ctx, inv, p.ID, again, now)
 	if err != nil {
 		return p, said, fmt.Errorf("%s is not stopped: %w", p.ID, err)
 	}
@@ -261,8 +262,10 @@ func stopWalkWithout(ctx context.Context, inv *inventory.Inventory, id, by, why
 	if len(said.Kept) > 0 {
 		p.Note += "; " + keptWords(said.Kept)
 	}
-	// The batch first, so no merge names a plan the store does not hold; all of it, or nothing (decision 7).
-	if err := inv.SavePlansMoving(ctx, []*inventory.Plan{&target, &p}, moves); err != nil {
+	// The batch first, so no merge names a plan the store does not hold; all of it, or nothing (decision 7) — the
+	// batches folded into it too.
+	if err := inv.SavePlansMoving(ctx, append([]*inventory.Plan{&target, &p}, folded...),
+		append(moves, foldMoves...)); err != nil {
 		return p, said, fmt.Errorf("%s is not stopped, and none of its merges moved: %w", p.ID, err)
 	}
 	// What the batch holds and names now: written again by the cutter's next look should this fail.
@@ -317,36 +320,42 @@ func stopInBatch(ctx context.Context, inv *inventory.Inventory, b *inventory.Pla
 	return nil
 }
 
-// batchToWalkAgain is the batch a stopped walk's merges join: the open batch of their kind, or a new one, not yet
-// written. The kind is read from what the merges moved.
-func batchToWalkAgain(ctx context.Context, inv *inventory.Inventory, again []inventory.BatchedMerge,
-	now time.Time) (inventory.Plan, error) {
+// batchToWalkAgain is the batch a stopped walk's merges join (novox/hq ADR 0299): a batch of their kind not yet cut
+// that they are related to (ADR 0304 decision 1, ADR 0306 decision 3), or a new one, not yet written. Related to
+// two or more, the newer are folded into the oldest: the plans and merge moves that fold them, to be written in
+// the stop's one act. The kind is read from what the merges moved; the stopped walk itself is no walk a cut folds.
+func batchToWalkAgain(ctx context.Context, inv *inventory.Inventory, stopping string, again []inventory.BatchedMerge,
+	now time.Time) (inventory.Plan, []*inventory.Plan, []inventory.MergeMove, error) {
 	own := false
 	for _, n := range movesOf(again) {
 		if _, on := onTheControllersPath[n]; on {
 			own = true
 		}
 	}
-	batches, err := inv.Batches(ctx)
+	entries, read, edges, err := theGraph(ctx, inv)
 	if err != nil {
-		return inventory.Plan{}, err
+		return inventory.Plan{}, nil, nil, err
 	}
-	for _, b := range batches {
-		if b.OwnPath() == own {
-			if b.Delivery == nil {
-				b.Delivery = &inventory.PlanDelivery{}
-			}
-			if b.Delivery.Batch == nil {
-				b.Delivery.Batch = &inventory.PlanBatch{Own: own}
-			}
-			return b, nil
+	joins, _, _, err := relatedBatches(ctx, inv, again, own, stopping, entries, read, edges)
+	if err != nil {
+		return inventory.Plan{}, nil, nil, err
+	}
+	if len(joins) > 0 {
+		into := joins[0]
+		if len(joins) == 1 {
+			return into, nil, nil, nil
 		}
+		plans, moves, err := foldInto(ctx, inv, &into, joins[1:])
+		if err != nil {
+			return inventory.Plan{}, nil, nil, err
+		}
+		return into, plans[1:], moves, nil
 	}
 	first := again[0]
 	return inventory.Plan{ID: fmt.Sprintf("plan-%d", now.UnixNano()), Repository: first.Repository, Branch: first.Branch,
 		Commit: first.Commit, Merged: first.Merged, Created: now, State: inventory.PlanAssembling,
 		Tiers: [][]string{}, Modules: map[string]*inventory.PlanModule{},
-		Delivery: &inventory.PlanDelivery{Batch: &inventory.PlanBatch{Own: own}}}, nil
+		Delivery: &inventory.PlanDelivery{Batch: &inventory.PlanBatch{Own: own}}}, nil, nil, nil
 }
 
 // leaveOut splits a walk's merges by the merges named to leave out, each `<repository>@<commit>` (a commit's
@@ -571,6 +580,9 @@ type orderMember struct {
 	CloneURL       string   `json:"clone_url,omitempty"`
 	// After are the repositories its pull request says it goes after (`after: <repository>`).
 	After []string `json:"after,omitempty"`
+	// BaseSHA is the base branch's head the forge last announced the head with (novox/hq ADR 0323): the trunk commit
+	// a verdict no build judges names when the head is checked again through mesh-delivery.
+	BaseSHA string `json:"base_sha,omitempty"`
 }
 
 // pull is the member as the forge announced it.
@@ -580,7 +592,7 @@ func (m orderMember) pull() link.PullUpdated {
 	if base == "" {
 		base = "main"
 	}
-	return link.PullUpdated{Owner: owner, Repo: repo, Number: m.Number, Base: base, Commit: m.Head,
+	return link.PullUpdated{Owner: owner, Repo: repo, Number: m.Number, Base: base, Commit: m.Head, BaseSHA: m.BaseSHA,
 		CloneURL: m.CloneURL, Paths: m.Paths, PathsTruncated: m.PathsTruncated, Removed: m.Removed,
 		ModuleDirs: m.ModuleDirs, ModuleDirsSaid: m.ModuleDirsSaid}
 }
@@ -940,7 +952,7 @@ func deliveryCommand(ctx context.Context, args []string) error {
 		if *group == "" && len(members) == 1 {
 			// One head, checked again as the forge's announcement would have it (a recheck): the controller's
 			// own path for a pull request, run because the delivery's owner asked.
-			if err := sayingOnTheBus(ctx, func() error { return (following{open}).PullUpdated(ctx, members[0].pull()) }); err != nil {
+			if err := sayingOnTheBus(ctx, inv, func() error { return (following{open}).PullUpdated(ctx, members[0].pull()) }); err != nil {
 				return err
 			}
 			return answer(map[string]any{"rechecked": members[0].ID})
@@ -958,7 +970,7 @@ func deliveryCommand(ctx context.Context, args []string) error {
 			return errors.New("delivery go <plan> [--by <who>] [--why <text>]")
 		}
 		var p inventory.Plan
-		if err := sayingOnTheBus(ctx, func() (err error) {
+		if err := sayingOnTheBus(ctx, inv, func() (err error) {
 			p, err = letGo(ctx, inv, positionals[0], *by, strings.TrimSpace(*why))
 			return err
 		}); err != nil {
@@ -973,7 +985,7 @@ func deliveryCommand(ctx context.Context, args []string) error {
 		}
 		var p inventory.Plan
 		var said stopAnswer
-		if err := sayingOnTheBus(ctx, func() (err error) {
+		if err := sayingOnTheBus(ctx, inv, func() (err error) {
 			p, said, err = stopWalkWithout(ctx, inv, positionals[0], *by, strings.TrimSpace(*why), splitList(*without),
 				time.Now().UTC())
 			return err
@@ -1030,13 +1042,13 @@ func deliveryCommand(ctx context.Context, args []string) error {
 	return fmt.Errorf("delivery %s: plan, order, check, go, stop or walks", sub)
 }
 
-// appliedFrom answers a machine's first report after a send from the controller's `apply` durations; a lookup
-// that fails is a report not read, which leaves the walk's end unknown rather than wrong.
+// appliedFrom answers a machine's own report of the send a walk made to it from the controller's `apply` durations
+// (novox/hq issue 582); a lookup that fails is a report not read, which leaves the walk's end unknown rather than wrong.
 func appliedFrom(ctx context.Context, inv *inventory.Inventory) inventory.AppliedLookup {
-	return func(node string, sent time.Time) (inventory.AppliedReport, bool) {
-		r, ok, err := inv.FirstAppliedAfter(ctx, node, sent)
+	return func(node string, send inventory.SentDeclaration, walkSent time.Time) (inventory.AppliedReport, bool) {
+		r, ok, err := inv.FirstAppliedAfter(ctx, node, send, walkSent)
 		if err != nil {
-			fmt.Fprintf(os.Stderr, "the report of %s after %s could not be read: %v\n", node, sent.Format(time.RFC3339), err)
+			fmt.Fprintf(os.Stderr, "the report of %s after %s could not be read: %v\n", node, walkSent.Format(time.RFC3339), err)
 			return inventory.AppliedReport{}, false
 		}
 		return r, ok
@@ -1176,7 +1188,7 @@ func askGroupCheck(ctx context.Context, open *stores, group string, members []or
 			return "", fmt.Errorf("%s cannot be cloned for the group's check: %w", m.ID, err)
 		}
 		request.Check.Members = append(request.Check.Members, link.GroupMember{Owner: mp.Owner, Repo: mp.Repo,
-			Number: mp.Number, Repository: url, Ref: mp.Commit, Paths: mp.Paths})
+			Number: mp.Number, Repository: url, Ref: mp.Commit, Paths: mp.Paths, Base: mp.Base})
 	}
 	seat := buildSeatHeld(ctx)
 	ask, err := askOverOn(seat)
@@ -1215,15 +1227,19 @@ func shelfOf(entries []inventory.Entry) map[string]catalogue.Manifest {
 // delivery it walks reads its steps from. Never in the way of the walk: said beside it, and a save that could
 // not be said is logged — the delivery's owner, which also asks for the walks it follows, finds it by
 // comparison. Records arriving out of order are told apart by the plan's revision.
-func sayPlanMoved(ctx context.Context, bus link.Bus, p inventory.Plan) {
-	go publishPlanMoved(ctx, bus, p)
+//
+// On the save that starts the walk and the one that ends it, the walk also says what it touches, its bound and,
+// at the end, its outcome (novox/hq ADR 0308 decision 1, walk_said.go), read from facts; nil facts say only what
+// the walk recorded.
+func sayPlanMoved(ctx context.Context, bus link.Bus, facts walkFacts, p inventory.Plan) {
+	go publishPlanMoved(ctx, bus, facts, p)
 }
 
-func publishPlanMoved(ctx context.Context, bus link.Bus, p inventory.Plan) {
+func publishPlanMoved(ctx context.Context, bus link.Bus, facts walkFacts, p inventory.Plan) {
 	// Its phases so far (novox/hq ADR 0282 decision 6): the rest's reports come after the walk ends, and are
 	// read by whoever asks for the walk (`delivery walks`).
 	p.Phases = p.WalkPhases(time.Now(), nil)
-	body, err := json.Marshal(p)
+	body, err := json.Marshal(planMovedBody{Plan: p, walkSaid: sayWalk(ctx, facts, p)})
 	if err != nil {
 		return
 	}
@@ -1238,7 +1254,7 @@ func publishPlanMoved(ctx context.Context, bus link.Bus, p inventory.Plan) {
 // controller's, or a connection of the command's own — a verb runs as a command of its own, and what it kept
 // would otherwise be said by nobody until the delivery's owner read the walks back. Without a bus the command
 // still runs; what it did is found by comparison.
-func sayingOnTheBus(ctx context.Context, f func() error) error {
+func sayingOnTheBus(ctx context.Context, facts walkFacts, f func() error) error {
 	if checkEvents != nil {
 		return f()
 	}
@@ -1249,9 +1265,10 @@ func sayingOnTheBus(ctx context.Context, f func() error) error {
 			return err
 		}
 		bus := link.OverNATS{Conn: conn, JS: js}
+		was := inventory.PlanSaved
 		checkEvents = bus
-		inventory.PlanSaved = func(p inventory.Plan) { publishPlanMoved(ctx, bus, p) }
-		defer func() { checkEvents, inventory.PlanSaved = nil, nil }()
+		inventory.PlanSaved = func(_ *inventory.Inventory, p inventory.Plan) { publishPlanMoved(ctx, bus, facts, p) }
+		defer func() { checkEvents, inventory.PlanSaved = nil, was }()
 		ran = true
 		return f()
 	})
@@ -1261,3 +1278,65 @@ func sayingOnTheBus(ctx context.Context, f func() error) error {
 	}
 	return err
 }
+
+// sayingWhatAVerbKept is PlanSaved for a process that is not the serving controller: each walk the verb keeps is
+// said as `plan-moved` before the save returns, with the facts of the inventory that kept it, on the bus the verb
+// reaches. It reaches the bus on the first save and never for a verb that keeps no walk. When the bus cannot be
+// reached, a save that started or ended a walk says so on the verb's error output: its mark is kept and no later
+// save says it, so the router holds what the walk touched until its bound, or not at all for a start. done lets
+// the bus go and takes the hook back.
+func sayingWhatAVerbKept(ctx context.Context) (said func(*inventory.Inventory, inventory.Plan), done func()) {
+	var (
+		mu      sync.Mutex
+		reached bool
+		bus     link.Bus
+		closing func()
+		failed  error
+	)
+	said = func(inv *inventory.Inventory, p inventory.Plan) {
+		mu.Lock()
+		defer mu.Unlock()
+		if !reached {
+			reached = true
+			if handActConn != nil {
+				bus, failed = overNATS(handActConn)
+			} else if js, err := aBus(); err != nil {
+				failed = err
+			} else if bus, failed = overNATS(js.Conn()); failed == nil {
+				closing = js.Close
+			} else {
+				js.Close()
+			}
+		}
+		if bus == nil {
+			switch p.WalkSaid {
+			case inventory.WalkStarted:
+				fmt.Fprintf(os.Stderr, "%s: its start is kept and could NOT be said as plan-moved (%v): the router "+
+					"does not hold what it touches\n", p.ID, failed)
+			case inventory.WalkEnded:
+				fmt.Fprintf(os.Stderr, "%s: its end is kept and could NOT be said as plan-moved (%v): the router holds "+
+					"what it touched until its bound\n", p.ID, failed)
+			}
+			return
+		}
+		publishPlanMoved(ctx, bus, inv, p)
+	}
+	done = func() {
+		mu.Lock()
+		defer mu.Unlock()
+		inventory.PlanSaved = nil
+		if closing != nil {
+			closing()
+		}
+	}
+	return said, done
+}
+
+// overNATS is the bus a connection carries, with its JetStream.
+func overNATS(conn *nats.Conn) (link.Bus, error) {
+	js, err := conn.JetStream()
+	if err != nil {
+		return nil, err
+	}
+	return link.OverNATS{Conn: conn, JS: js}, nil
+}

cmd/mesh-controller/delivery_conditions.go

@@ -47,10 +47,14 @@ type stalledLine struct {
 	// issue 443): a time inside a finished sentence cannot be said again in another zone. A mesh-delivery from before
 	// says none, and Waiting is said as it reads.
 	Checks []waitingCheck `json:"checks,omitempty"`
-	For    string         `json:"for"`
-	Bound  string         `json:"bound"`
-	H2     string         `json:"h2"`
-	Says   string         `json:"says"`
+	// Held is the state of the delivery of a line of the state `unanswered`, ready or rejected, when one is held
+	// (novox/hq issues 441, 451): its check answered once, so a recheck is the step. Empty for a head with no
+	// delivery, and from a mesh-delivery that does not say it yet; the words are never read for it.
+	Held  string `json:"held,omitempty"`
+	For   string `json:"for"`
+	Bound string `json:"bound"`
+	H2    string `json:"h2"`
+	Says  string `json:"says"`
 }
 
 // waitingCheck is one merge check a stalled line waits on, as mesh-delivery gives it: its context, its state —

cmd/mesh-controller/delivery_order_test.go

@@ -119,6 +119,13 @@ func TestTheBusMachineIsBehindByItsUserListAlone(t *testing.T) {
 	if userListBehind("", "") {
 		t.Fatal("a machine sent no list reads as behind")
 	}
+	// A list that could not be composed is behind: not known is never "not behind" (the review of hq issue 353).
+	if !listBehind("", errors.New("the plan cannot be worked out"), digestOf([]byte(list))) {
+		t.Fatal("a list nobody could compose reads as current")
+	}
+	if listBehind(list, nil, digestOf([]byte(list))) || !listBehind(list, nil, "") {
+		t.Fatal("listBehind does not read the digest as userListBehind does")
+	}
 }
 
 // The machine holding the bus goes first: its declaration carries the user list the new grants are

cmd/mesh-controller/fixclass_test.go

@@ -0,0 +1,54 @@
+package main
+
+import (
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// **A change plan says its class** (novox/hq ADR 0313 §2): the issue tracker holds a fix to the budget of the
+// slowest-budgeted module the fix moves, and a fix that moves no module has no fix budget. The plan says core,
+// leaf or none, so mesh-delivery can pass it on with the fix's delivery.
+func TestAChangePlanSaysTheClassOfWhatItMoves(t *testing.T) {
+	const repo = "http://forge.internal:20000/novox/mesh-catalog.git"
+	entry := func(name, path string) inventory.Entry {
+		e := fromRepo(name, repo, path)
+		e.Source.BuiltFrom = "old"
+		e.On = []string{"anchor"}
+		return e
+	}
+	gitea := entry("gitea", "modules/gitea")
+	resolver := entry("dnsmasq", "modules/dnsmasq")
+	resolver.Manifest.Claims = []catalogue.Claim{{Name: resolverSeat}}
+	delivery := entry(catalogue.DeliverySeat, "modules/mesh-delivery")
+	webApp := entry("photos", "modules/photos")
+	entries := []inventory.Entry{gitea, resolver, delivery, webApp}
+	// photos stands on gitea: a change to gitea moves photos as its dependent.
+	edges := []inventory.Edge{{From: "photos", To: "gitea", Kind: inventory.EdgeStandsOn}}
+	policy := func(string) (inventory.Upgrade, bool) { return inventory.Upgrade{RollOut: true}, true }
+	plan := func(paths ...string) link.ChangePlan {
+		m := link.SourceMoved{Owner: "novox", Repo: "mesh-catalog", Base: "main", Commit: "head", Paths: paths}
+		return changePlanOf("novox/mesh-catalog", "main", "head", reachOfMerge(m, entries, nil, edges), entries, policy)
+	}
+
+	for _, c := range []struct {
+		why   string
+		paths []string
+		want  string
+	}{
+		{"a leaf module and its dependent", []string{"modules/gitea/index.ts"}, inventory.ClassLeaf},
+		{"the delivery's owner, on the controller's own path", []string{"modules/mesh-delivery/cmd/x.go"}, inventory.ClassCore},
+		{"the mesh's resolver", []string{"modules/dnsmasq/module.json"}, inventory.ClassCore},
+		{"a leaf and a core module together: the slowest-budgeted", []string{"modules/gitea/index.ts", "modules/dnsmasq/module.json"}, inventory.ClassCore},
+		{"nothing any module's build reads", []string{"README.md"}, "none"},
+		{"a new leaf module alone", []string{"modules/weather/module.json"}, inventory.ClassLeaf},
+		{"a new module on the controller's own path, by its own class", []string{"next/mesh-delivery/module.json"}, inventory.ClassCore},
+		{"a new leaf module beside a core one moved", []string{"modules/weather/module.json", "modules/dnsmasq/module.json"}, inventory.ClassCore},
+	} {
+		if got := plan(c.paths...).Class; got != c.want {
+			t.Errorf("%s: class %q, want %q", c.why, got, c.want)
+		}
+	}
+}

cmd/mesh-controller/gate.go

@@ -1039,7 +1039,7 @@ func gateFailed(ctx context.Context, open *stores, p *inventory.Plan, module str
 		}
 		return
 	}
-	sent, err := sendRollout(withScope(ctx, sendScope{modules: map[string]bool{module: true}}), open, g.Machines)
+	sent, err := sendRollout(withScope(ctx, sendScope{modules: map[string]bool{module: true}, puttingBack: true}), open, g.Machines)
 	if err != nil {
 		notBack(fmt.Sprintf("its registered build is back at %s, and sending it to %s was refused: %v — `push %s` "+
 			"sends it", short(previous.Commit), strings.Join(g.Machines, ", "), err, g.Machines[0]))
@@ -1132,7 +1132,7 @@ func sendRollbacks(ctx context.Context, open *stores, p *inventory.Plan, b *roll
 	}
 	inv := open.inventory
 	sort.Strings(b.machines)
-	sent, err := sendRollout(withScope(ctx, sendScope{modules: b.modules}), open, b.machines)
+	sent, err := sendRollout(withScope(ctx, sendScope{modules: b.modules, puttingBack: true}), open, b.machines)
 	var back []string
 	for _, r := range b.pending {
 		if err != nil {

cmd/mesh-controller/group_wait.go

@@ -0,0 +1,158 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// **A delivery group still assembles** (novox/hq ADR 0306 decision 2): a merge whose delivery group has a member
+// not yet merged waits for the merge window, whether or not a batch is assembling, so the group's members walk in
+// one batch, in their order (ADR 0276 decision 5). Which groups exist and where each member stands is
+// mesh-delivery's record (ADR 0239): a group is the pull requests of two repositories or more sharing a head
+// branch name, which is its id. The controller asks it, through its `groups` verb, when a merge from a head is
+// heard; a member whose pull request is open (proposed, checked, ready or rejected) is still to merge. When
+// mesh-delivery does not answer within groupAskWithin, or answers something unreadable, the merge waits: the safe
+// error is to wait, and its batch says why.
+
+// groupAskWithin is how long mesh-delivery is given to say a merge's group, while the merge is being heard.
+var groupAskWithin = 3 * time.Second
+
+// openPullStates are the states of a delivery whose pull request is open and not merged (mesh-delivery's table):
+// a member in one of them is still to merge. Closed unmerged is stopped, final, and waits for nothing.
+var openPullStates = map[string]bool{"proposed": true, "checked": true, "ready": true, "rejected": true}
+
+// groupMember is one member of a delivery group as mesh-delivery's `groups` says it: `<owner/repo>@<commit> (state)`.
+type groupMember struct {
+	Repository, State string
+}
+
+// deliveryGroupOf is what mesh-delivery says of the group a head names: its members, and whether the head names a
+// group at all; an error when it cannot be asked or did not answer. A seam a test replaces.
+var deliveryGroupOf = func(ctx context.Context, held bool, head string) ([]groupMember, bool, error) {
+	if !held {
+		return nil, false, fmt.Errorf("no holder of %s is on record to say it", catalogue.DeliverySeat)
+	}
+	serving := servingBus.Load()
+	if serving == nil {
+		return nil, false, errors.New("this controller is not on the bus")
+	}
+	asking, cancel := context.WithTimeout(ctx, groupAskWithin)
+	defer cancel()
+	raw, err := askDeliveryOwner(asking, serving.Conn(), "groups", map[string]any{})
+	if err != nil {
+		if errors.Is(err, link.ErrNothingServes) {
+			return nil, false, fmt.Errorf("nothing serves %s.groups", catalogue.DeliverySeat)
+		}
+		return nil, false, err
+	}
+	var lines []struct {
+		ID      string   `json:"id"`
+		Members []string `json:"members"`
+	}
+	if err := json.Unmarshal(raw, &lines); err != nil {
+		return nil, false, fmt.Errorf("%s.groups answered something unreadable: %w", catalogue.DeliverySeat, err)
+	}
+	for _, l := range lines {
+		if l.ID != head {
+			continue
+		}
+		var members []groupMember
+		for _, s := range l.Members {
+			members = append(members, memberOf(s))
+		}
+		return members, true, nil
+	}
+	return nil, false, nil
+}
+
+// memberOf reads one member as `groups` says it: `novox/mesh-sdk@d41d255f28ad (held)`.
+func memberOf(s string) groupMember {
+	id, state := strings.TrimSpace(s), ""
+	if i := strings.LastIndex(id, " ("); i >= 0 && strings.HasSuffix(id, ")") {
+		id, state = id[:i], id[i+2:len(id)-1]
+	}
+	repository, _, _ := strings.Cut(id, "@")
+	return groupMember{Repository: repository, State: state}
+}
+
+// groupWait says whether a merge heard now waits for the window for its delivery group, and why in words; nothing
+// when it names no head, its head names no group, or every other member is merged or closed. own is the merge's
+// kind (ownPath).
+//
+// A member of another repository whose merge this controller already keeps in a batch not yet cut of the same
+// kind is merged, whatever mesh-delivery says yet (it marks a member merged once its walk opened): the merge joins
+// that batch by their head. One kept in a batch of the other kind keeps the merge waiting, whatever mesh-delivery
+// says (review of #250): kinds never share a batch, so the merge's batch is a new one, and cut at once it would
+// walk before that member's batch is cut and break the group's order (ADR 0276 decision 5). Waiting, the two
+// batches are cut in the order their windows close, an own-path one first at one look, as cutBatchesHeld cuts
+// every pair of kinds.
+//
+// Asked before the plans are held: a slow answer holds up no walk.
+func groupWait(ctx context.Context, inv *inventory.Inventory, m link.SourceMoved, held, own bool) (string, error) {
+	if m.Head == "" {
+		return "", nil
+	}
+	same, other, err := keptFromHead(ctx, inv, m.Head, own)
+	if err != nil {
+		return "", err
+	}
+	if len(other) > 0 {
+		return "group " + m.Head + " has a member waiting in a batch of the other kind: " + strings.Join(other, ", "), nil
+	}
+	members, isGroup, err := deliveryGroupOf(ctx, held, m.Head)
+	if err != nil {
+		return fmt.Sprintf("%s did not say whether group %s has a member still to merge (%v): it waits for the "+
+			"window, the safe side", catalogue.DeliverySeat, m.Head, err), nil
+	}
+	if !isGroup {
+		return "", nil
+	}
+	var open []string
+	for _, g := range members {
+		if strings.EqualFold(g.Repository, m.Owner+"/"+m.Repo) || same[strings.ToLower(g.Repository)] ||
+			!openPullStates[g.State] {
+			continue
+		}
+		open = append(open, g.Repository+" ("+g.State+")")
+	}
+	if len(open) == 0 {
+		return "", nil
+	}
+	return "group " + m.Head + " has a member still to merge: " + strings.Join(open, ", "), nil
+}
+
+// keptFromHead are the merges from a head that batches not yet cut hold: the repositories (lower case) of those in
+// a batch of the kind own says, and, in words, each of the other kind with its batch.
+func keptFromHead(ctx context.Context, inv *inventory.Inventory, head string, own bool) (map[string]bool, []string, error) {
+	batches, err := inv.Batches(ctx)
+	if err != nil {
+		return nil, nil, err
+	}
+	same := map[string]bool{}
+	var other []string
+	for _, b := range batches {
+		merges, err := inv.MergesOf(ctx, b.ID)
+		if err != nil {
+			return nil, nil, err
+		}
+		for _, k := range merges {
+			if announcedOf(k).Head != head {
+				continue
+			}
+			if b.OwnPath() == own {
+				same[strings.ToLower(k.Repository)] = true
+			} else {
+				other = append(other, fmt.Sprintf("%s@%s in %s", k.Repository, short(k.Commit), b.ID))
+			}
+		}
+	}
+	return same, other, nil
+}

cmd/mesh-controller/handover_test.go

@@ -167,3 +167,54 @@ func TestASetuidSearchAsksOnlyAKnownNodeAndFailsOnARefusal(t *testing.T) {
 		t.Fatalf("a start: %v, printed %q", err, out.String())
 	}
 }
+
+// The directory judgement's line asks only a known node, one name and nothing else, fails on a refusal, and says it
+// changed nothing (novox/hq issue 358).
+func TestADirectoryJudgementAsksOnlyAKnownNodeAndSaysItIsReadOnly(t *testing.T) {
+	t.Setenv(link.CallerVar, "jo through mesh-cli on anchor")
+	asked := 0
+	ask := func(answer link.HandOverAnswer) func(node, by string) (link.HandOverAnswer, error) {
+		return func(node, by string) (link.HandOverAnswer, error) {
+			asked++
+			if node != "novox" || by != "jo through mesh-cli on anchor" {
+				t.Fatalf("asked %q %q", node, by)
+			}
+			return answer, nil
+		}
+	}
+	known := func(string) error { return nil }
+	var out bytes.Buffer
+	for _, args := range [][]string{nil, {"novox", "extra"}, {"-x"}} {
+		if err := judgeDirectoriesAsked(args, known, ask(link.HandOverAnswer{Said: "x"}), &out); err == nil || asked != 0 {
+			t.Fatalf("%v was asked: %v", args, err)
+		}
+	}
+	if err := judgeDirectoriesAsked([]string{"novox"}, func(string) error { return errors.New("no node called novox") },
+		ask(link.HandOverAnswer{Said: "x"}), &out); err == nil || asked != 0 {
+		t.Fatalf("an unknown node: %v", err)
+	}
+	if err := judgeDirectoriesAsked([]string{"novox"}, known, ask(link.HandOverAnswer{Refused: "no; nothing was judged"}),
+		&out); err == nil || !strings.Contains(err.Error(), "novox refused") || out.Len() != 0 {
+		t.Fatalf("a refusal: %v, printed %q", err, out.String())
+	}
+	said := "2 directories declared: 1 placed, 1 would be refused\n/var/lib/a: placed\n/var/lib/b: would be refused: …"
+	if err := judgeDirectoriesAsked([]string{"novox"}, known, ask(link.HandOverAnswer{Said: said}), &out); err != nil ||
+		out.String() != "novox (read-only: nothing on novox was changed)\n"+said+"\n" {
+		t.Fatalf("a judgement: %v, printed %q", err, out.String())
+	}
+}
+
+// The judgement is a seat verb an agent may call — it reads, and changes nothing on the node — and runs exactly
+// `node judge-directories <node>` (novox/hq issue 358).
+func TestTheDirectoryJudgementIsAVerbThatOnlyReads(t *testing.T) {
+	argv, err := argvFor("judge-directories", map[string]any{"node": "novox"})
+	if err != nil || strings.Join(argv, " ") != "node judge-directories novox" {
+		t.Fatalf("the verb runs %v, %v", argv, err)
+	}
+	if _, err := argvFor("judge-directories", map[string]any{}); err == nil {
+		t.Fatal("the verb ran with no node")
+	}
+	if !readingVerbs["judge-directories"] {
+		t.Fatal("the judgement is not counted a reading verb")
+	}
+}

cmd/mesh-controller/issue201_test.go

@@ -0,0 +1,259 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/lease"
+)
+
+// novox/hq issue 201: on 2026-10-02 a plan sent the control node a controller older than the one running there,
+// whose seat row the newer one had already widened; the older binary refused the row and the mesh went quiet for
+// ten minutes. No send but a person's push and a gate's own put-back moves the controller or the node-engine back
+// behind the build its machine was last sent: the send keeps it there, and carries the rest.
+
+// askedIn answers a build from a fixed table: module@commit → when it was asked; failed names those that failed
+// their gate.
+func askedIn(table map[string]time.Time, failed ...string) func(module, commit string) (askedBuild, bool, error) {
+	return func(module, commit string) (askedBuild, bool, error) {
+		at, known := table[module+"@"+commit]
+		b := askedBuild{asked: at}
+		for _, f := range failed {
+			if f == module+"@"+commit {
+				b.failedGate = true
+			}
+		}
+		return b, known, nil
+	}
+}
+
+func TestACoreModuleIsKeptOverAnOlderRecord(t *testing.T) {
+	old, now := t0, t0.Add(time.Minute)
+	table := map[string]time.Time{
+		"mesh-controller@c1": old, "mesh-controller@c2": now,
+		"mesh-host@h1": old, "mesh-host@h2": now,
+		"app@a1": old, "app@a2": now,
+	}
+	sent := map[string]string{"mesh-controller": "c2", "mesh-host": "h2", "app": "a2"}
+	record := map[string]string{"mesh-controller": "c1", "mesh-host": "h1", "app": "a1"}
+	found, err := coreDowngrades("anchor", sent, record, sendScope{judged: map[string]bool{"anchor": true}}, askedIn(table))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(found) != 2 || found[0].module != "mesh-controller" || found[0].component != lease.ComponentController ||
+		found[0].sent != "c2" || found[1].module != "mesh-host" || found[1].component != lease.ComponentEngine {
+		t.Fatalf("the controller and the node-engine over an older record are kept, and nothing else: %+v", found)
+	}
+	if said := found[0].String(); !strings.Contains(said, "anchor was last sent mesh-controller c2") ||
+		!strings.Contains(said, "`push anchor`") || !strings.Contains(said, "`rebuild mesh-controller`") {
+		t.Fatalf("it says the machine, the build kept and the two ways out: %s", said)
+	}
+
+	// The record forward, the same build, or a build the records do not hold: nothing kept.
+	for _, c := range [][2]string{{"c1", "c2"}, {"c2", "c2"}, {"c2", "c9"}, {"c9", "c1"}} {
+		found, err := coreDowngrades("anchor", map[string]string{"mesh-controller": c[0]},
+			map[string]string{"mesh-controller": c[1]}, sendScope{}, askedIn(table))
+		if err != nil || len(found) != 0 {
+			t.Fatalf("sent %s, record %s: no downgrade proved, nothing kept: %+v %v", c[0], c[1], found, err)
+		}
+	}
+
+	// A sent build that failed its gate is never ahead: the record put back before it is sent.
+	if found, _ := coreDowngrades("anchor", sent, record, sendScope{}, askedIn(table, "mesh-controller@c2")); len(found) != 1 ||
+		found[0].module != "mesh-host" {
+		t.Fatalf("a controller that failed its gate was kept over the build put back: %+v", found)
+	}
+
+	// A gate's own put-back carries its own modules back, and nothing else.
+	putBack := sendScope{modules: map[string]bool{"mesh-controller": true}, puttingBack: true}
+	if found, _ := coreDowngrades("anchor", sent, record, putBack, askedIn(table)); len(found) != 1 || found[0].module != "mesh-host" {
+		t.Fatalf("a put-back of the controller carries it back, and not the node-engine: %+v", found)
+	}
+	if found, _ := coreDowngrades("anchor", sent, record, sendScope{modules: map[string]bool{"mesh-controller": true}},
+		askedIn(table)); len(found) != 2 {
+		t.Fatalf("a send for the controller that is no put-back carries it back: %+v", found)
+	}
+}
+
+// core201 is a mesh whose control node, anchor, was sent the newer controller c2 while the mesh's record of the
+// controller is the build before it, c1, which passed its gate when it rolled out.
+func core201(t *testing.T) *stores {
+	t.Helper()
+	open := aMesh(t)
+	ctx := t.Context()
+	inv := open.inventory
+	old, now := time.Now().Add(-2*time.Hour), time.Now().Add(-time.Minute)
+	record := func(commit string, asked time.Time) inventory.Build {
+		manifest, _ := json.Marshal(catalogue.Manifest{Module: "mesh-controller", Version: "1"})
+		b := inventory.Build{ID: "build-mesh-controller-" + commit, Module: "mesh-controller", Commit: commit,
+			Repository: "novox/mesh-controller", Manifest: manifest, Asked: asked, At: asked,
+			Made: []inventory.Artifact{{Name: "x", Kind: "bundle", Reference: "sha256:" + commit + "0000000000000000"}}}
+		if err := inv.RecordBuild(ctx, b); err != nil {
+			t.Fatal(err)
+		}
+		return b
+	}
+	before := record("c1aaaaaaaaaa", old)
+	if err := inv.RecordGate(ctx, inventory.GateVerdict{Build: before.ID, Module: "mesh-controller", Commit: before.Commit,
+		Machines: []string{"anchor"}, Verdict: inventory.GatePassed}); err != nil {
+		t.Fatal(err)
+	}
+	record("c2bbbbbbbbbb", now)
+	if err := inv.RegisterModule(ctx, catalogue.Manifest{Module: "mesh-controller", Version: "1"}, inventory.Source{
+		Repository: "novox/mesh-controller", BuiltFrom: "c2bbbbbbbbbb", Head: "c2bbbbbbbbbb", Asked: now}); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := inv.Assign(ctx, "anchor", "mesh-controller"); err != nil {
+		t.Fatal(err)
+	}
+	if err := inv.RecordSent(ctx, nodeID(t, open, "anchor"), "d-anchor", map[string]string{"mesh-controller": "c2bbbbbbbbbb"}); err != nil {
+		t.Fatal(err)
+	}
+	if err := inv.RestoreModule(ctx, before); err != nil {
+		t.Fatal(err)
+	}
+	wasMoves := machineMoves
+	machineMoves = func(ctx context.Context, open *stores, f moveFacts, node string, all bool) ([]inventory.CarriedMove, error) {
+		modules, err := open.inventory.Assigned(ctx, node)
+		if err != nil {
+			return nil, err
+		}
+		sent, known, err := open.inventory.SentBuilds(ctx, node)
+		if err != nil {
+			return nil, err
+		}
+		return f.moves(node, modules, sent, known, all), nil
+	}
+	t.Cleanup(func() { machineMoves = wasMoves })
+	return open
+}
+
+// TestReplay201 replays the race on a store: the control node runs the newer controller and the mesh's record is
+// the build before it. A plan's send there — the node-engine's plan of 2026-10-02 — goes, keeps the newer
+// controller, and says so as a condition; the gate's own put-back carries it back; a send that carries the record,
+// as a person's push does, clears the condition.
+func TestReplay201(t *testing.T) {
+	open := core201(t)
+	ctx := t.Context()
+	k, _ := withConditionsInMemory(t)
+
+	judged := withScope(ctx, sendScope{judged: map[string]bool{"anchor": true}})
+	if kept, err := ungatedIn(judged, open, []string{"anchor"}, ""); err != nil || len(kept) != 1 {
+		t.Fatalf("a plan's send to the machine is made, the rest of it with it: %v %v", kept, err)
+	}
+	keeps, err := recordedKept(keepingRecorded(judged), open, "anchor")
+	if err != nil || keeps["mesh-controller"] != "c2bbbbbbbbbb" {
+		t.Fatalf("the send keeps the newer controller there: %v %v", keeps, err)
+	}
+	shelf := map[string]catalogue.Manifest{"mesh-controller": {Module: "mesh-controller", Version: "old"}}
+	if _, err := keepRecorded(keepingRecorded(judged), open, "anchor", shelf); err != nil || shelf["mesh-controller"].Version != "1" {
+		t.Fatalf("the send composes the kept build's manifest: %+v %v", shelf, err)
+	}
+	key := coreDowngradeObservation(lease.ComponentController, "anchor", "").Key()
+	if c, found, err := k.Get(ctx, key); err != nil || !found || !strings.Contains(c.Summary, "c2bbbbbb") {
+		t.Fatalf("the condition %s is raised, saying the build kept: %+v %v %v", key, c, found, err)
+	}
+
+	putBack := keepingRecorded(withScope(ctx, sendScope{modules: map[string]bool{"mesh-controller": true}, puttingBack: true}))
+	if keeps, err := recordedKept(putBack, open, "anchor"); err != nil || len(keeps) != 0 {
+		t.Fatalf("the gate's own put-back of the controller carries it back: %v %v", keeps, err)
+	}
+
+	settleCoreDowngrades(ctx, open.inventory, "anchor", map[string]string{"mesh-controller": "c2bbbbbbbbbb"})
+	if _, found, _ := k.Get(ctx, key); !found {
+		t.Fatal("a send that kept the newer controller cleared the condition")
+	}
+	settleCoreDowngrades(ctx, open.inventory, "anchor", map[string]string{"mesh-controller": "c1aaaaaaaaaa"})
+	if _, found, _ := k.Get(ctx, key); found {
+		t.Fatal("a send carrying the mesh's record — a person's push — leaves the condition open")
+	}
+}
+
+// The review of #273: a gate failed the newer controller, put the record back, and the put-back's own send was
+// refused. The next automatic send — a healer's, which judges nothing — completes the put-back: a build that
+// failed its gate is never kept.
+func TestARollbackWhoseSendWasRefusedIsCompletedByTheNextSend(t *testing.T) {
+	open := core201(t)
+	ctx := t.Context()
+	k, _ := withConditionsInMemory(t)
+	if err := open.inventory.RecordGate(ctx, inventory.GateVerdict{Build: "build-mesh-controller-c2bbbbbbbbbb",
+		Module: "mesh-controller", Commit: "c2bbbbbbbbbb", Previous: "c1aaaaaaaaaa", Machines: []string{"anchor"},
+		Verdict: inventory.GateFailed, Rollback: inventory.NotRolledBack}); err != nil {
+		t.Fatal(err)
+	}
+	healer := withScope(ctx, sendScope{})
+	if kept, err := ungatedIn(healer, open, []string{"anchor"}, ""); err != nil || len(kept) != 1 {
+		t.Fatalf("the healer's send is made: %v %v", kept, err)
+	}
+	if keeps, err := recordedKept(keepingRecorded(healer), open, "anchor"); err != nil || len(keeps) != 0 {
+		t.Fatalf("the failed controller was kept over the build put back: %v %v", keeps, err)
+	}
+	if open, _ := k.Open(ctx); len(open) != 0 {
+		t.Fatalf("a completed put-back raised a condition: %+v", open)
+	}
+}
+
+// Review 91 of #273: a gated send to a machine whose controller is kept over an older record leaves the kept
+// controller out of what its gate judges. Judged as moving back to the record, the gate would read the send's own
+// kept controller as another build sent there after it (issue 352) and be superseded, judging nothing.
+func TestAGateJudgesTheOtherMovesBesideAKeptCore(t *testing.T) {
+	open := core201(t)
+	ctx := t.Context()
+	withConditionsInMemory(t)
+	inv := open.inventory
+	old, now := time.Now().Add(-2*time.Hour), time.Now().Add(-time.Minute)
+	for _, b := range []struct {
+		commit string
+		at     time.Time
+	}{{"a1aaaaaaaaaa", old}, {"a2bbbbbbbbbb", now}} {
+		manifest, _ := json.Marshal(catalogue.Manifest{Module: "app", Version: "1"})
+		if err := inv.RecordBuild(ctx, inventory.Build{ID: "build-app-" + b.commit, Module: "app", Commit: b.commit,
+			Repository: "novox/mesh-catalog", Path: "modules/app", Manifest: manifest, Asked: b.at, At: b.at,
+			Made: []inventory.Artifact{{Name: "x", Kind: "bundle", Reference: "sha256:app-" + b.commit}}}); err != nil {
+			t.Fatal(err)
+		}
+		if err := inv.RegisterModule(ctx, catalogue.Manifest{Module: "app", Version: "1"}, inventory.Source{
+			Repository: "novox/mesh-catalog", Seat: "git", Path: "modules/app", BuiltFrom: b.commit, Head: b.commit,
+			Asked: b.at}); err != nil {
+			t.Fatal(err)
+		}
+	}
+	if _, err := inv.Assign(ctx, "anchor", "app"); err != nil {
+		t.Fatal(err)
+	}
+	if err := inv.RecordSent(ctx, nodeID(t, open, "anchor"), "d-anchor-2",
+		map[string]string{"mesh-controller": "c2bbbbbbbbbb", "app": "a1aaaaaaaaaa"}); err != nil {
+		t.Fatal(err)
+	}
+	// The send as it is made: the controller kept at c2, the app moved to the record.
+	wasSend := sendRollout
+	sendRollout = func(ctx context.Context, open *stores, names []string) ([]string, error) {
+		return names, open.inventory.RecordSent(ctx, nodeID(t, open, "anchor"), "d-anchor-3",
+			map[string]string{"mesh-controller": "c2bbbbbbbbbb", "app": "a2bbbbbbbbbb"})
+	}
+	t.Cleanup(func() { sendRollout = wasSend })
+
+	moves, sent, _, err := gatedSend(ctx, open, "anchor", nil)
+	if err != nil || len(sent) != 1 {
+		t.Fatalf("the gated send is made: %v %v", sent, err)
+	}
+	if len(moves) != 1 || moves[0].Module != "app" || moves[0].To != "a2bbbbbbbbbb" {
+		t.Fatalf("the gate judges the app's move and not the kept controller: %+v", moves)
+	}
+	builds, _, err := inv.SentBuilds(ctx, "anchor")
+	if err != nil {
+		t.Fatal(err)
+	}
+	g := &inventory.PlanGate{Carried: moves}
+	f := gateFacts{commits: judgedCommits(g, nil), sentBuilds: map[string]map[string]string{"anchor": builds}}
+	for _, m := range []string{"app", "mesh-controller"} {
+		if why, superseded := f.supersededOn(m, "anchor"); superseded {
+			t.Fatalf("the gate is superseded by its own send: %s", why)
+		}
+	}
+}

cmd/mesh-controller/issue459_test.go

@@ -123,11 +123,12 @@ func TestDeliveryStopTakesTheMergesToLeaveOut(t *testing.T) {
 // that builds the other repository's module alone.
 func TestAStopWithoutAMergeWalksTheOthersAgain(t *testing.T) {
 	open := windowed(t)
+	groupsWaiting(t, "pr/cat1aaaaaaaa")
 	endsItsLine(t)
 	asksRecorded(t)
 	ctx := t.Context()
 	cat := catalogueMerge("cat1aaaaaaaa", "app", t0)
-	one := repoMerge("one", "one1bbbbbbbb", t0.Add(5*time.Second))
+	one := fromHead(repoMerge("one", "one1bbbbbbbb", t0.Add(5*time.Second)), cat.Head)
 	hear(t, open, cat, t0.Add(time.Second))
 	hear(t, open, one, t0.Add(6*time.Second))
 	cutAt(t, open, t0.Add(2*time.Minute))
@@ -181,12 +182,13 @@ func TestAStopWithoutAMergeWalksTheOthersAgain(t *testing.T) {
 // ended. A merge the walk does not answer is refused, and nothing ends.
 func TestAStopWithoutAMergeEndsTheMergesThatContainIt(t *testing.T) {
 	open := windowed(t)
+	groupsWaiting(t, "pr/cat1aaaaaaaa")
 	endsItsLine(t)
 	asksRecorded(t)
 	ctx := t.Context()
 	first := catalogueMerge("cat1aaaaaaaa", "app", t0)
 	later := catalogueMerge("cat2cccccccc", "notes", t0.Add(10*time.Second))
-	one := repoMerge("one", "one1bbbbbbbb", t0.Add(5*time.Second))
+	one := fromHead(repoMerge("one", "one1bbbbbbbb", t0.Add(5*time.Second)), first.Head)
 	hear(t, open, first, t0.Add(time.Second))
 	hear(t, open, one, t0.Add(6*time.Second))
 	hear(t, open, later, t0.Add(11*time.Second))
@@ -238,11 +240,12 @@ func TestAStopWithoutAMergeEndsTheMergesThatContainIt(t *testing.T) {
 // (review of #232): its window closes, and its walk is at the newer commit, answering both.
 func TestAStopWalksTheOthersAgainInTheOpenBatch(t *testing.T) {
 	open := windowed(t)
+	groupsWaiting(t, "pr/cat1aaaaaaaa")
 	endsItsLine(t)
 	asksRecorded(t)
 	ctx := t.Context()
 	cat := catalogueMerge("cat1aaaaaaaa", "app", t0)
-	one1 := repoMerge("one", "one1bbbbbbbb", t0.Add(5*time.Second))
+	one1 := fromHead(repoMerge("one", "one1bbbbbbbb", t0.Add(5*time.Second)), cat.Head)
 	hear(t, open, cat, t0.Add(time.Second))
 	hear(t, open, one1, t0.Add(6*time.Second))
 	cutAt(t, open, t0.Add(2*time.Minute))
@@ -290,11 +293,12 @@ func TestAStopWalksTheOthersAgainInTheOpenBatch(t *testing.T) {
 // that walked its merges again is refused a retry, saying why.
 func TestAStopNamesWhatStaysOnTheMachinesAndWhatStillCarriesIt(t *testing.T) {
 	open := windowed(t)
+	groupsWaiting(t, "pr/cat1aaaaaaaa")
 	endsItsLine(t)
 	asksRecorded(t)
 	ctx := t.Context()
 	cat := catalogueMerge("cat1aaaaaaaa", "app", t0)
-	one1 := repoMerge("one", "one1bbbbbbbb", t0.Add(5*time.Second))
+	one1 := fromHead(repoMerge("one", "one1bbbbbbbb", t0.Add(5*time.Second)), cat.Head)
 	hear(t, open, cat, t0.Add(time.Second))
 	hear(t, open, one1, t0.Add(6*time.Second))
 	cutAt(t, open, t0.Add(2*time.Minute))
@@ -335,11 +339,12 @@ func TestAStopNamesWhatStaysOnTheMachinesAndWhatStillCarriesIt(t *testing.T) {
 // with the others and withholds the stopped merge's modules; with every merge left out, the batch is stopped.
 func TestAStopWithoutAMergeLeavesItOutOfABatch(t *testing.T) {
 	open := windowed(t)
+	everyHeadWaits(t)
 	endsItsLine(t)
 	asksRecorded(t)
 	ctx := t.Context()
 	cat := catalogueMerge("cat1aaaaaaaa", "app", t0)
-	one := repoMerge("one", "one1bbbbbbbb", t0.Add(5*time.Second))
+	one := fromHead(repoMerge("one", "one1bbbbbbbb", t0.Add(5*time.Second)), cat.Head)
 	hear(t, open, cat, t0.Add(time.Second))
 	hear(t, open, one, t0.Add(6*time.Second))
 	_, bs := walks(t, open)
@@ -382,6 +387,7 @@ func TestAStopWithoutAMergeLeavesItOutOfABatch(t *testing.T) {
 // else since it was read refuses all of it, and no merge moves, no plan is written.
 func TestSavingPlansAndMovingMergesIsOneAct(t *testing.T) {
 	open := windowed(t)
+	everyHeadWaits(t)
 	endsItsLine(t)
 	ctx := t.Context()
 	hear(t, open, catalogueMerge("cat1aaaaaaaa", "app", t0), t0.Add(time.Second))

cmd/mesh-controller/lone_merge_test.go

@@ -0,0 +1,398 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// The tests of novox/hq issue 525's window skip: a merge waits for the merge window only when a batch assembling
+// holds a merge related to it, or its delivery group may have a member still to merge (ADR 0304 decision 1, ADR
+// 0306 decisions 2 and 3). Walks stay one at a time.
+
+// A merge from no head that shares nothing, with no walk open, is cut into its walk when it is heard: no window.
+func TestALoneMergeSharingNothingIsCutAtOnce(t *testing.T) {
+	open := windowed(t)
+	asksWithPaths(t)
+	hear(t, open, lone(repoMerge("one", "c1", t0)), t0)
+	ws, bs := walks(t, open)
+	if len(ws) != 1 || len(bs) != 0 || !ws[0].Open() || ws[0].Commit != "c1" {
+		t.Fatalf("a lone merge sharing nothing: %d walk(s) %+v, %d batch(es)", len(ws), ws, len(bs))
+	}
+	if ws[0].Times == nil || ws[0].Times.WindowClosed == nil || !ws[0].Times.WindowClosed.Equal(t0) {
+		t.Fatalf("its window closed at %+v; want when it was heard, %s", ws[0].Times, t0)
+	}
+}
+
+// A merge related to the batch assembling joins it and waits for the window, which its coming restarts: by its
+// repository, by a module in common (a dependent of what the batch moves), by an edge of the module graph between
+// their modules (one that widens nothing), or by its delivery group's head.
+func TestARelatedMergeJoinsTheBatchAndWaitsForTheWindow(t *testing.T) {
+	ctx := t.Context()
+	for _, c := range []string{"same repository", "a module in common", "an edge of the graph", "the same group head"} {
+		t.Run(c, func(t *testing.T) {
+			open := windowed(t)
+			groupsWaiting(t, "pr/c1")
+			asksWithPaths(t)
+			inv := open.inventory
+			first := repoMerge("one", "c1", t0)
+			second := lone(repoMerge("two", "c2", t0.Add(10*time.Second)))
+			why := map[string]string{"same repository": "both change novox/one", "a module in common": "both move two",
+				"an edge of the graph": "two depends on builder (built-by)",
+				"the same group head":  "both are members of group " + first.Head}[c]
+			switch c {
+			case "same repository":
+				second = lone(repoMerge("one", "c2", t0.Add(10*time.Second)))
+			case "a module in common":
+				// two is built on one: a merge of one moves two too.
+				if err := inv.RegisterModule(ctx, catalogue.Manifest{Module: "two", Version: "1",
+					Build: &catalogue.Build{On: []catalogue.BuildsOn{{Arg: "BASE", Module: "one"}}}},
+					inventory.Source{Repository: "novox/two", Seat: "git", Ref: "main", BuiltFrom: "c0", Head: "c0"}); err != nil {
+					t.Fatal(err)
+				}
+			case "an edge of the graph":
+				// two is built by the build machine: an edge that orders and widens nothing.
+				if err := inv.RegisterModule(ctx, catalogue.Manifest{Module: "builder", Version: "1",
+					Claims: []catalogue.Claim{{Name: "mesh-build-machine", Scope: catalogue.ScopeMesh}}},
+					inventory.Source{Repository: "novox/builder", Seat: "git", Ref: "main", BuiltFrom: "c0", Head: "c0"}); err != nil {
+					t.Fatal(err)
+				}
+				first = repoMerge("builder", "c1", t0)
+			case "the same group head":
+				second = fromHead(repoMerge("two", "c2", t0.Add(10*time.Second)), first.Head)
+			}
+			hear(t, open, first, t0)
+			said := captured(t, func() error {
+				return (following{open: open}).hearMerge(ctx, second, t0.Add(10*time.Second))
+			})
+			if !strings.Contains(said, "("+why+")") {
+				t.Fatalf("the merge was not said related by %q: %s", why, said)
+			}
+			ws, bs := walks(t, open)
+			if len(ws) != 0 || len(bs) != 1 || len(bs[0].Delivery.Merges) != 2 {
+				t.Fatalf("the related merge: %d walk(s), batches %+v", len(ws), bs)
+			}
+			if bs[0].Delivery.Batch.CutAtOnce {
+				t.Fatal("a batch a related merge joined is cut at once")
+			}
+			cutAt(t, open, t0.Add(99*time.Second))
+			if ws, _ := walks(t, open); len(ws) != 0 {
+				t.Fatalf("cut before the window the related merge restarted closed: %+v", ws)
+			}
+			cutAt(t, open, t0.Add(100*time.Second))
+			ws, bs = walks(t, open)
+			if len(ws) != 1 || len(bs) != 0 || len(ws[0].Delivery.Merges) != 2 {
+				t.Fatalf("after the window: %d walk(s), %d batch(es)", len(ws), len(bs))
+			}
+		})
+	}
+}
+
+// A merge from a head whose delivery group has a member still to merge waits for the window, even with no batch
+// assembling, and says why; its sibling joins the same batch by their head (ADR 0306 decision 2). A merge from a
+// head that names no group shares nothing and is cut at once, as one from no head is.
+func TestAMergeOfAGroupWaitsEvenAlone(t *testing.T) {
+	open := windowed(t)
+	asksWithPaths(t)
+	groupsWaiting(t, "feat/x")
+	hear(t, open, fromHead(repoMerge("one", "c1", t0), "feat/x"), t0)
+	ws, bs := walks(t, open)
+	if len(ws) != 0 || len(bs) != 1 || bs[0].Delivery.Batch.CutAtOnce || windowClosed(bs[0], t0) {
+		t.Fatalf("a group's merge alone: %d walk(s), batches %+v", len(ws), bs)
+	}
+	if words := batchWords(bs[0], t0); !strings.HasPrefix(words, "assembling: 90 s left") ||
+		!strings.Contains(words, "group feat/x has a member still to merge: novox/elsewhere (ready)") {
+		t.Fatalf("it reads %q", words)
+	}
+	hear(t, open, fromHead(repoMerge("two", "c2", t0.Add(5*time.Second)), "feat/x"), t0.Add(5*time.Second))
+	if _, bs := walks(t, open); len(bs) != 1 || len(bs[0].Delivery.Merges) != 2 {
+		t.Fatalf("the group's second member did not join the first: %+v", bs)
+	}
+	cutAt(t, open, t0.Add(94*time.Second))
+	if ws, _ := walks(t, open); len(ws) != 0 {
+		t.Fatalf("cut before its window closed: %+v", ws)
+	}
+	cutAt(t, open, t0.Add(95*time.Second))
+	ws, bs = walks(t, open)
+	if len(ws) != 1 || len(bs) != 0 || ws[0].CommitOf("novox/one") != "c1" || ws[0].CommitOf("novox/two") != "c2" {
+		t.Fatalf("at its window: %d walk(s) %+v, %d batch(es)", len(ws), ws, len(bs))
+	}
+}
+
+// A merge from a head that names no group, sharing nothing, with no walk open, is cut at once.
+func TestAHeadedMergeInNoGroupIsCutAtOnce(t *testing.T) {
+	open := windowed(t)
+	asksWithPaths(t)
+	hear(t, open, fromHead(repoMerge("one", "c1", t0), "fix/alone"), t0)
+	if ws, bs := walks(t, open); len(ws) != 1 || len(bs) != 0 || !ws[0].Open() {
+		t.Fatalf("a headed merge in no group: %d walk(s), %d batch(es)", len(ws), len(bs))
+	}
+}
+
+// When mesh-delivery cannot say a head's group, the merge waits for the window, the safe side, and its batch says
+// why.
+func TestAGroupNobodyCanSayWaits(t *testing.T) {
+	open := windowed(t)
+	asksWithPaths(t)
+	was := deliveryGroupOf
+	deliveryGroupOf = func(context.Context, bool, string) ([]groupMember, bool, error) {
+		return nil, false, errors.New("nothing serves mesh-delivery.groups")
+	}
+	t.Cleanup(func() { deliveryGroupOf = was })
+	hear(t, open, fromHead(repoMerge("one", "c1", t0), "feat/x"), t0)
+	ws, bs := walks(t, open)
+	if len(ws) != 0 || len(bs) != 1 || bs[0].Delivery.Batch.CutAtOnce {
+		t.Fatalf("a merge whose group nobody could say: %d walk(s), batches %+v", len(ws), bs)
+	}
+	if words := batchWords(bs[0], t0); !strings.Contains(words, "mesh-delivery did not say whether group feat/x has a "+
+		"member still to merge (nothing serves mesh-delivery.groups): it waits for the window, the safe side") {
+		t.Fatalf("it reads %q", words)
+	}
+}
+
+// A member counts as still to merge only while its pull request is open, and not once this controller keeps its
+// merge: a group whose other members are merged or closed makes nobody wait.
+func TestAGroupsMergedOrClosedMembersMakeNobodyWait(t *testing.T) {
+	open := windowed(t)
+	asksWithPaths(t)
+	ctx := t.Context()
+	members := []groupMember{{Repository: "novox/one", State: "ready"}, {Repository: "novox/two", State: "published"},
+		{Repository: "novox/three", State: "stopped"}}
+	was := deliveryGroupOf
+	deliveryGroupOf = func(context.Context, bool, string) ([]groupMember, bool, error) { return members, true, nil }
+	t.Cleanup(func() { deliveryGroupOf = was })
+	m := fromHead(repoMerge("one", "c1", t0), "feat/x")
+	if why, err := groupWait(ctx, open.inventory, m, true, false); err != nil || why != "" {
+		t.Fatalf("the group's other members are merged or closed, yet: %q %v", why, err)
+	}
+	members = append(members, groupMember{Repository: "novox/four", State: "checked"})
+	if why, _ := groupWait(ctx, open.inventory, m, true, false); !strings.Contains(why, "novox/four (checked)") {
+		t.Fatalf("an open member: %q", why)
+	}
+	// novox/four's merge is kept in a batch already: merged, whatever mesh-delivery says yet.
+	hear(t, open, fromHead(repoMerge("two", "c4", t0), "feat/x"), t0)
+	members[3].Repository = "novox/two"
+	if why, _ := groupWait(ctx, open.inventory, m, true, false); why != "" {
+		t.Fatalf("a member this controller keeps the merge of still waits: %q", why)
+	}
+	if got := memberOf("novox/mesh-sdk@d41d255f28ad (held)"); got != (groupMember{Repository: "novox/mesh-sdk", State: "held"}) {
+		t.Fatalf("a member reads %+v", got)
+	}
+}
+
+// A merge related to two batches assembling folds the newer into the older, which answers every merge of both
+// and names nothing twice; the folded one names the batch that took it over.
+func TestAMergeRelatedToTwoBatchesFoldsThem(t *testing.T) {
+	open := windowed(t)
+	groupsWaiting(t, "feat/a", "feat/b")
+	asksWithPaths(t)
+	ctx := t.Context()
+	hear(t, open, fromHead(repoMerge("one", "c1", t0), "feat/a"), t0)
+	hear(t, open, fromHead(repoMerge("two", "c2", t0.Add(5*time.Second)), "feat/b"), t0.Add(5*time.Second))
+	_, bs := walks(t, open)
+	if len(bs) != 2 {
+		t.Fatalf("two merges sharing nothing: %d batch(es)", len(bs))
+	}
+	older, newer := bs[1], bs[0] // newest first
+	// Of one's repository and from two's head: related to both.
+	hear(t, open, fromHead(repoMerge("one", "c3", t0.Add(10*time.Second)), "feat/b"), t0.Add(10*time.Second))
+	_, bs = walks(t, open)
+	if len(bs) != 1 || bs[0].ID != older.ID || len(bs[0].Delivery.Merges) != 3 {
+		t.Fatalf("after a merge related to both: batches %+v; want %s answering three merges", bs, older.ID)
+	}
+	folded, err := open.inventory.PlanByID(ctx, newer.ID)
+	if err != nil || folded.State != inventory.PlanSuperseded || folded.Delivery == nil ||
+		folded.Delivery.TakenOverBy != older.ID {
+		t.Fatalf("the newer batch reads %s %+v (%v)", folded.State, folded.Delivery, err)
+	}
+	if left, _ := open.inventory.MergesOf(ctx, newer.ID); len(left) != 0 {
+		t.Fatalf("the folded batch still answers %+v", left)
+	}
+	cutAt(t, open, t0.Add(100*time.Second))
+	ws, bs := walks(t, open)
+	var cut []inventory.Plan
+	for _, w := range ws {
+		if w.State != inventory.PlanSuperseded {
+			cut = append(cut, w)
+		}
+	}
+	if len(cut) != 1 || len(bs) != 0 || cut[0].ID != older.ID || cut[0].CommitOf("novox/one") != "c3" ||
+		cut[0].CommitOf("novox/two") != "c2" {
+		t.Fatalf("the folded batch's walk: %+v, %d batch(es)", cut, len(bs))
+	}
+}
+
+// With a walk open, a batch cut at once still waits for it, said queued behind it (walks stay one at a time, ADR
+// 0276 decision 4); it is cut once that walk ended, with no window to wait for.
+func TestACutAtOnceBatchQueuesBehindAnOpenWalk(t *testing.T) {
+	open := windowed(t)
+	groupsWaiting(t, "pr/c1")
+	asksWithPaths(t)
+	hear(t, open, repoMerge("one", "c1", t0), t0)
+	cutAt(t, open, t0.Add(90*time.Second))
+	ws, _ := walks(t, open)
+	if len(ws) != 1 || !ws[0].Open() {
+		t.Fatalf("no walk open: %+v", ws)
+	}
+	first := ws[0]
+	heard := t0.Add(100 * time.Second)
+	hear(t, open, lone(repoMerge("two", "c2", heard)), heard)
+	ws, bs := walks(t, open)
+	if len(ws) != 1 || len(bs) != 1 || bs[0].State != inventory.PlanQueued || bs[0].Delivery.Batch.Behind != first.ID ||
+		!bs[0].Delivery.Batch.CutAtOnce {
+		t.Fatalf("a lone merge during a walk: %d walk(s), batches %+v", len(ws), bs)
+	}
+	if !strings.HasPrefix(batchWords(bs[0], heard), "queued behind "+first.ID) {
+		t.Fatalf("it reads %q", batchWords(bs[0], heard))
+	}
+	first.State = inventory.PlanDone
+	if err := open.inventory.SavePlan(t.Context(), &first); err != nil {
+		t.Fatal(err)
+	}
+	cutAt(t, open, heard.Add(time.Second))
+	ws, bs = walks(t, open)
+	if len(ws) != 2 || len(bs) != 0 || ws[0].Commit != "c2" {
+		t.Fatalf("the queued batch was not cut once the walk ended: %+v %+v", ws, bs)
+	}
+	if ws[0].Times == nil || ws[0].Times.WindowClosed == nil || !ws[0].Times.WindowClosed.Equal(heard) {
+		t.Fatalf("its window closed at %+v; want when its merge was heard, %s", ws[0].Times, heard)
+	}
+}
+
+// A stopped walk's other merges are walked again in a batch they are related to, and a batch of their own when
+// they share nothing with the one assembling (ADR 0299, ADR 0304 decision 1): never in a batch of another
+// change, whose window the stop would close.
+func TestAStopWalksTheOthersAgainInABatchOfTheirOwnWhenTheyShareNothing(t *testing.T) {
+	open := windowed(t)
+	groupsWaiting(t, "pr/cat1aaaaaaaa")
+	endsItsLine(t)
+	asksRecorded(t)
+	ctx := t.Context()
+	cat := catalogueMerge("cat1aaaaaaaa", "app", t0)
+	one := fromHead(repoMerge("one", "one1bbbbbbbb", t0.Add(5*time.Second)), cat.Head)
+	hear(t, open, cat, t0.Add(time.Second))
+	hear(t, open, one, t0.Add(6*time.Second))
+	cutAt(t, open, t0.Add(2*time.Minute))
+	ws, _ := walks(t, open)
+	walk := ws[0]
+	hear(t, open, repoMerge("two", "two1cccccccc", t0.Add(3*time.Minute)), t0.Add(3*time.Minute))
+	_, bs := walks(t, open)
+	if len(bs) != 1 {
+		t.Fatalf("the merge heard while the walk ran is in %d batches", len(bs))
+	}
+	other := bs[0]
+	_, said, err := stopWalkWithout(ctx, open.inventory, walk.ID, "mesh-delivery for jochen", "its group stopped",
+		[]string{"novox/mesh-catalog@" + cat.Commit}, t0.Add(3*time.Minute+10*time.Second))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if said.WalkedAgainBy == "" || said.WalkedAgainBy == other.ID {
+		t.Fatalf("walked again by %q; want a batch of its own, not %s", said.WalkedAgainBy, other.ID)
+	}
+	b, _ := open.inventory.PlanByID(ctx, other.ID)
+	if b.Delivery.Batch == nil || b.Delivery.Batch.Closed || len(b.Delivery.Merges) != 1 {
+		t.Fatalf("the other change's batch reads %+v; want it untouched by the stop", b.Delivery)
+	}
+}
+
+// A catalogue batch's cut folds in every walk waiting for its delivery's word (cutBatch's carry), so what that
+// walk moves is the batch's too: a lone merge related to the waiting walk joins the batch assembling and waits for
+// its window, rather than being cut at once as sharing nothing with what the batch's own merges move.
+func TestALoneMergeRelatedToAWalkTheCutFoldsJoinsTheBatch(t *testing.T) {
+	open := windowed(t)
+	groupsWaiting(t, "pr/c3")
+	asksWithPaths(t)
+	ctx := t.Context()
+	if err := open.inventory.RegisterModule(ctx, catalogue.Manifest{Module: "mesh-delivery", Version: "1",
+		Claims: []catalogue.Claim{{Name: catalogue.DeliverySeat, Scope: catalogue.ScopeMesh}}},
+		inventory.Source{Repository: "novox/mesh-catalog", Seat: "git", Path: "modules/mesh-delivery", Ref: "main",
+			BuiltFrom: "c0", Head: "c0"}); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := open.inventory.Assign(ctx, "anchor", "mesh-delivery"); err != nil {
+		t.Fatal(err)
+	}
+	hear(t, open, repoMerge("one", "c1", t0), t0)
+	cutAt(t, open, t0.Add(90*time.Second))
+	if ws, _ := walks(t, open); len(ws) != 1 || !ws[0].Waiting() {
+		t.Fatalf("the walk does not wait for its word: %+v", ws)
+	}
+	hear(t, open, repoMerge("three", "c3", t0.Add(2*time.Minute)), t0.Add(2*time.Minute))
+	hear(t, open, lone(repoMerge("one", "c2", t0.Add(2*time.Minute+5*time.Second))), t0.Add(2*time.Minute+5*time.Second))
+	_, bs := walks(t, open)
+	if len(bs) != 1 || len(bs[0].Delivery.Merges) != 2 || bs[0].Delivery.Batch.CutAtOnce {
+		t.Fatalf("a lone merge related to the waiting walk: batches %+v", bs)
+	}
+}
+
+// A delivery group with a member of each kind (review of #250): a merge on the controller's own path and a
+// catalogue merge never share a batch, so the later member cannot join the earlier one's. Kept in a batch of the
+// other kind, the earlier member keeps the later one waiting, whatever mesh-delivery says yet — never cut at once
+// to walk before it. The two batches are then cut in the order their windows close (cutBatchesHeld: the oldest
+// closed batch first, an own-path one first at one look, and the other queued behind a walk that started): the
+// earlier member's window closes first, so it walks first, in both orders.
+func TestAGroupAcrossBothKindsKeepsItsOrder(t *testing.T) {
+	for _, ownFirst := range []bool{true, false} {
+		name := "catalogue member first"
+		if ownFirst {
+			name = "controller member first"
+		}
+		t.Run(name, func(t *testing.T) {
+			open := windowed(t)
+			asksWithPaths(t)
+			ctx := t.Context()
+			was := deliveryGroupOf
+			// mesh-delivery still says both members ready: it marks one merged only once its walk opened.
+			deliveryGroupOf = func(context.Context, bool, string) ([]groupMember, bool, error) {
+				return []groupMember{{Repository: "novox/mesh-controller", State: "ready"},
+					{Repository: "novox/mesh-catalog", State: "ready"}}, true, nil
+			}
+			t.Cleanup(func() { deliveryGroupOf = was })
+			own := fromHead(repoMerge("mesh-controller", "k1", t0), "feat/both-kinds")
+			cat := fromHead(catalogueMerge("cat1aaaaaaaa", "app", t0), "feat/both-kinds")
+			first, second := cat, own
+			if ownFirst {
+				first, second = own, cat
+			}
+			second.MergedAt = t0.Add(10 * time.Second).Format(time.RFC3339Nano)
+			hear(t, open, first, t0)
+			hear(t, open, second, t0.Add(10*time.Second))
+			ws, bs := walks(t, open)
+			if len(ws) != 0 || len(bs) != 2 {
+				t.Fatalf("both members heard: %d walk(s), %d batch(es); want two batches, nothing cut", len(ws), len(bs))
+			}
+			later := bs[0] // newest first
+			if later.Delivery.Batch.CutAtOnce || !strings.Contains(later.Delivery.Batch.Waits,
+				"has a member waiting in a batch of the other kind: novox/"+first.Repo+"@") {
+				t.Fatalf("the later member's batch reads %+v; want it waiting for the earlier member", later.Delivery.Batch)
+			}
+			// The earlier member's window closes first: its batch alone is cut.
+			cutAt(t, open, t0.Add(90*time.Second))
+			ws, bs = walks(t, open)
+			if len(ws) != 1 || !ws[0].Open() || ws[0].CommitOf("novox/"+first.Repo) != first.Commit || len(bs) != 1 ||
+				bs[0].ID != later.ID {
+				t.Fatalf("at the earlier window: walks %+v, batches %+v; want the earlier member alone cut", ws, bs)
+			}
+			earlier := ws[0]
+			// The later member's window closes while the earlier walk runs: it queues behind it.
+			cutAt(t, open, t0.Add(100*time.Second))
+			if _, bs := walks(t, open); len(bs) != 1 || bs[0].State != inventory.PlanQueued || bs[0].Delivery.Batch.Behind != earlier.ID {
+				t.Fatalf("the later member's batch does not queue behind the earlier walk: %+v", bs)
+			}
+			earlier.State = inventory.PlanDone
+			if err := open.inventory.SavePlan(ctx, &earlier); err != nil {
+				t.Fatal(err)
+			}
+			cutAt(t, open, t0.Add(101*time.Second))
+			got, err := open.inventory.PlanByID(ctx, later.ID)
+			if err != nil || got.Batch() || got.CommitOf("novox/"+second.Repo) != second.Commit {
+				t.Fatalf("the later member was not walked after the earlier: %s %v", got.State, err)
+			}
+		})
+	}
+}

cmd/mesh-controller/machine_lines.go

@@ -0,0 +1,135 @@
+package main
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// machineLines is what a machine said it is made of (novox/hq issue 160), as `node` shows it: every fact in
+// one block with its age, the architecture and kernel the profile always carried among them, and each fact
+// the machine could not determine said as unknown with its why — never as a zero, and never left out.
+func machineLines(a inventory.MachineAccount, had bool, now time.Time) []string {
+	if !had {
+		return []string{"  what it is made of: never said — this machine has not reported a profile"}
+	}
+	m := a.Machine
+	if m == nil {
+		return []string{
+			"  what it is made of: not said — its node-engine is older than the one that says it",
+			"    " + factLine("architecture", orUnsaid(a.Architecture)),
+			"    " + factLine("kernel", orUnsaid(a.Kernel)),
+		}
+	}
+	age := roughly(now.Sub(m.ObservedAt)) + " ago"
+	if m.ObservedAt.IsZero() {
+		// Said with no time: its age is not known, and is never read as two thousand years.
+		age = "at a time it did not say (age unknown)"
+	}
+	out := []string{fmt.Sprintf("  what it is made of, as it said %s:", age)}
+	add := func(name, value string) { out = append(out, "    "+factLine(name, value)) }
+	unknown := map[string]string{}
+	for k, v := range m.Unknown {
+		unknown[k] = v
+	}
+	// said is the value, or the fact's own reason it is unknown; a fact neither said nor unknown is a
+	// node-engine that broke its own rule, and is said so rather than shown blank.
+	said := func(fact, value string) string {
+		if value != "" {
+			delete(unknown, fact)
+			return value
+		}
+		if why, ok := unknown[fact]; ok {
+			delete(unknown, fact)
+			return "unknown: " + why
+		}
+		return "unknown: the machine said neither it nor why"
+	}
+
+	add("architecture", orUnsaid(a.Architecture))
+	release := said("kernel release", m.KernelRelease)
+	if m.KernelRelease == "" {
+		release = "(release " + release + ")"
+	}
+	add("kernel", orUnsaid(a.Kernel)+" "+release)
+	dist := said("distribution", m.Distribution)
+	if m.Distribution != "" {
+		dist += " " + said("version", m.Version)
+	}
+	add("distribution", dist)
+	add("processor", said("processor", m.Processor))
+	add("cores", said("cores", countWords(m.Cores)))
+	add("threads", said("threads", countWords(m.Threads)))
+	add("memory", said("memory", bytesWords(m.MemoryBytes)))
+	add("virtual", said("virtual or physical", m.Virtual))
+	up := ""
+	if m.BootedAt != nil {
+		up = fmt.Sprintf("%s, since %s", roughly(now.Sub(*m.BootedAt)), m.BootedAt.Local().Format("2006-01-02 15:04"))
+	}
+	add("up", said("uptime", up))
+	add("timezone", said("timezone", m.Timezone))
+	if len(m.Filesystems) == 0 {
+		add("filesystems", said("filesystems", ""))
+	} else {
+		for i, f := range m.Filesystems {
+			name := ""
+			if i == 0 {
+				name = "filesystems"
+			}
+			add(name, fmt.Sprintf("%s  %s, %s free (%s %s)", f.Mount, bytesWords(f.SizeBytes),
+				bytesWords(f.FreeBytes), f.Type, f.Device))
+		}
+		if why, ok := unknown["filesystems"]; ok {
+			add("", "and some unknown: "+why)
+			delete(unknown, "filesystems")
+		}
+	}
+	add("public address", said("public address", ""))
+	// Any other fact a newer node-engine named unknown, so nothing it said is dropped.
+	rest := make([]string, 0, len(unknown))
+	for k := range unknown {
+		rest = append(rest, k)
+	}
+	sort.Strings(rest)
+	for _, k := range rest {
+		add(k, "unknown: "+unknown[k])
+	}
+	return out
+}
+
+func factLine(name, value string) string { return fmt.Sprintf("%-15s %s", name, value) }
+
+func orUnsaid(s string) string {
+	if strings.TrimSpace(s) == "" {
+		return "not said"
+	}
+	return s
+}
+
+// countWords is a number a machine said, or nothing when it said none (its unknown says why).
+func countWords(n int) string {
+	if n <= 0 {
+		return ""
+	}
+	return fmt.Sprint(n)
+}
+
+// bytesWords is an amount of bytes a person reads, in binary units; nothing when none was said.
+func bytesWords(n int64) string {
+	if n <= 0 {
+		return ""
+	}
+	units := []string{"B", "KiB", "MiB", "GiB", "TiB", "PiB"}
+	v, u := float64(n), 0
+	for v >= 1024 && u < len(units)-1 {
+		v /= 1024
+		u++
+	}
+	if u == 0 {
+		return fmt.Sprintf("%d B", n)
+	}
+	return fmt.Sprintf("%.1f %s", v, units[u])
+}

cmd/mesh-controller/machine_lines_test.go

@@ -0,0 +1,88 @@
+package main
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// Defends novox/hq issue 160: `node` shows every fact a machine said it is made of, in one block with its
+// age, the architecture and kernel among them; and a fact it could not determine as unknown with why.
+func TestNodeShowsWhatAMachineIsMadeOfWithItsAge(t *testing.T) {
+	now := time.Date(2026, 10, 12, 15, 0, 0, 0, time.UTC)
+	booted := now.Add(-75 * time.Hour)
+	a := inventory.MachineAccount{Architecture: "amd64", Kernel: "linux", Machine: &inventory.MadeOf{
+		ObservedAt: now.Add(-3 * time.Hour), KernelRelease: "7.2.8-arch1-2", Distribution: "Arch Linux",
+		Version: "rolling", Processor: "AMD Ryzen 9 8945HS", Cores: 8, Threads: 16, MemoryBytes: 32891494400,
+		Virtual: "physical", BootedAt: &booted, Timezone: "Europe/Brussels",
+		Filesystems: []inventory.MountedFilesystem{{Mount: "/", Device: "/dev/nvme0n1p3", Type: "ext4",
+			SizeBytes: 987978522624, FreeBytes: 31830110208}},
+		Unknown: map[string]string{"public address": "how it learns it is not decided yet"},
+	}}
+	got := strings.Join(machineLines(a, true, now), "\n")
+	t.Log("\n" + got)
+	for _, want := range []string{
+		"what it is made of, as it said 3h ago:",
+		"architecture    amd64",
+		"kernel          linux 7.2.8-arch1-2",
+		"distribution    Arch Linux rolling",
+		"processor       AMD Ryzen 9 8945HS",
+		"cores           8",
+		"threads         16",
+		"memory          30.6 GiB",
+		"virtual         physical",
+		"up              3d, since",
+		"timezone        Europe/Brussels",
+		"filesystems     /  920.1 GiB, 29.6 GiB free (ext4 /dev/nvme0n1p3)",
+		"public address  unknown: how it learns it is not decided yet",
+	} {
+		if !strings.Contains(got, want) {
+			t.Errorf("missing %q", want)
+		}
+	}
+}
+
+func TestAFactAMachineCouldNotReadIsShownUnknownNeverZero(t *testing.T) {
+	now := time.Date(2026, 10, 12, 15, 0, 0, 0, time.UTC)
+	a := inventory.MachineAccount{Architecture: "arm64", Kernel: "linux", Machine: &inventory.MadeOf{
+		ObservedAt: now, Unknown: map[string]string{"memory": "MemTotal not found in /proc/meminfo",
+			"cores": "/proc/cpuinfo says no core id", "kernel release": "permission denied"}}}
+	got := strings.Join(machineLines(a, true, now), "\n")
+	t.Log("\n" + got)
+	for _, want := range []string{
+		"memory          unknown: MemTotal not found in /proc/meminfo",
+		"cores           unknown: /proc/cpuinfo says no core id",
+		"kernel          linux (release unknown: permission denied)",
+		// Neither said nor named unknown: the node-engine broke its rule, and that is shown.
+		"timezone        unknown: the machine said neither it nor why",
+	} {
+		if !strings.Contains(got, want) {
+			t.Errorf("missing %q", want)
+		}
+	}
+	if strings.Contains(got, " 0 ") || strings.Contains(got, "0 B") {
+		t.Error("a fact the machine could not read was shown as a zero")
+	}
+}
+
+func TestAnOlderNodeEngineStillShowsArchitectureAndKernel(t *testing.T) {
+	got := strings.Join(machineLines(inventory.MachineAccount{Architecture: "amd64", Kernel: "linux"}, true,
+		time.Now()), "\n")
+	if !strings.Contains(got, "older than the one that says it") || !strings.Contains(got, "architecture    amd64") ||
+		!strings.Contains(got, "kernel          linux") {
+		t.Errorf("%s", got)
+	}
+	if got := strings.Join(machineLines(inventory.MachineAccount{}, false, time.Now()), "\n"); !strings.Contains(got, "never said") {
+		t.Errorf("%s", got)
+	}
+}
+
+func TestAnAccountWithoutItsTimeSaysAgeUnknown(t *testing.T) {
+	got := machineLines(inventory.MachineAccount{Architecture: "amd64", Kernel: "linux",
+		Machine: &inventory.MadeOf{KernelRelease: "7.2"}}, true, time.Now())[0]
+	if !strings.Contains(got, "age unknown") || strings.Contains(got, "d ago") {
+		t.Errorf("%s", got)
+	}
+}

cmd/mesh-controller/main.go

@@ -63,6 +63,15 @@ func run() error {
 	// 45 §6), so the next controller takes it at once rather than after its age.
 	defer theLease.release()
 
+	// Every walk a verb keeps is said on the bus, whichever verb kept it (novox/hq ADR 0308 decision 1): the save
+	// that starts or ends a walk keeps its mark, and no later save says it again. The serving controller says its
+	// own saves.
+	if args[0] != "serve" {
+		said, done := sayingWhatAVerbKept(ctx)
+		inventory.PlanSaved = said
+		defer done()
+	}
+
 	switch args[0] {
 	case "build":
 		return buildCommand(ctx, args[1:])

cmd/mesh-controller/modules.go

@@ -237,7 +237,15 @@ func moduleCommand(ctx context.Context, args []string) error {
 				says = append(says, "provides "+describeOffers(m.Provides))
 			}
 			if len(m.Requires) > 0 {
-				says = append(says, "requires "+strings.Join(m.Requires, ", "))
+				// An optional requirement says so (novox/hq ADR 0330): it is not refused when absent.
+				required := make([]string, 0, len(m.Requires))
+				for _, r := range m.Requires {
+					if m.IsOptional(r) {
+						r += " (optional)"
+					}
+					required = append(required, r)
+				}
+				says = append(says, "requires "+strings.Join(required, ", "))
 			}
 			for _, c := range m.Claims {
 				says = append(says, "claims "+c.At()+"/"+c.Name)

cmd/mesh-controller/nodes.go

@@ -127,9 +127,14 @@ func nodeCommand(ctx context.Context, args []string) error {
 		// and whoever may call a verb includes agents.
 		return nodeSetuidSearch(ctx, open, args[1:])
 
+	case "judge-directories":
+		// Which of a node's declared directories the walk that follows no link another account could make would
+		// refuse (novox/hq issue 358). Read-only on the node and here, so a verb may run it too.
+		return nodeJudgeDirectories(ctx, open, args[1:])
+
 	default:
-		return fmt.Errorf("node has no %q; it has add, list, show, public-domain, account, agent-account, hand-over "+
-			"and setuid-search", args[0])
+		return fmt.Errorf("node has no %q; it has add, list, show, public-domain, account, agent-account, hand-over, "+
+			"setuid-search and judge-directories", args[0])
 	}
 }
 
@@ -870,6 +875,17 @@ func showNode(ctx context.Context, stored *stores, name string) error {
 		}
 	}
 
+	// What it is made of, in one block with its age (novox/hq issue 160): collected and shown in the same
+	// breath, so no fact the machine says is kept and read by nothing.
+	if account, had, err := inv.MachineOf(ctx, name); err != nil {
+		fmt.Printf("\n  what it is made of could NOT be read: %v\n", err)
+	} else {
+		fmt.Println()
+		for _, line := range machineLines(account, had, time.Now()) {
+			fmt.Println(line)
+		}
+	}
+
 	held, err := inv.Profile(ctx, name)
 	if err != nil {
 		return err
@@ -913,6 +929,13 @@ func showNode(ctx context.Context, stored *stores, name string) error {
 		for _, line := range notAppliedLines(name, leftOutOf(plan, settings, node.Adopted)) {
 			fmt.Println(line)
 		}
+		// And which optional requirements of its modules nothing assigned answers (novox/hq ADR 0330 §7).
+		if lines := unboundLines(plan); len(lines) > 0 {
+			fmt.Println()
+			for _, line := range lines {
+				fmt.Println(line)
+			}
+		}
 	}
 	return nil
 }
@@ -937,3 +960,57 @@ func printJSONTo(w io.Writer, v any) error {
 	fmt.Fprintln(w, string(body))
 	return nil
 }
+
+const judgeDirectoriesUsage = "node judge-directories <node> — read-only: which of the directories <node> is " +
+	"declared the node-engine's walk that follows no link another account could make would refuse, one line each " +
+	"(novox/hq issue 358). Nothing is made, chmodded or chowned"
+
+// nodeJudgeDirectories asks the node's engine to judge its declared directories, signed with the mesh's key as a
+// hand-over is. Read-only: the engine changes nothing and keeps nothing.
+func nodeJudgeDirectories(ctx context.Context, open *stores, args []string) error {
+	known := func(node string) error {
+		_, err := open.inventory.NodeByName(ctx, node)
+		return err
+	}
+	ask := func(node, by string) (link.HandOverAnswer, error) {
+		ident, err := open.Identity(ctx)
+		if err != nil {
+			return link.HandOverAnswer{}, fmt.Errorf("the mesh's signing key cannot be read, so nothing was asked of %s: %w",
+				node, err)
+		}
+		address, err := broker.BusAddress()
+		if err != nil {
+			return link.HandOverAnswer{}, err
+		}
+		js, err := broker.Dial(address)
+		if err != nil {
+			return link.HandOverAnswer{}, fmt.Errorf("cannot reach the bus, so nothing was asked of %s: %w", node, err)
+		}
+		defer js.Close()
+		return link.AskJudgeDirectories(ctx, js.Conn(), ident, node, by, link.HandOverWithin)
+	}
+	return judgeDirectoriesAsked(args, known, ask, os.Stdout)
+}
+
+// judgeDirectoriesAsked is the line with its two acts given: whether the mesh knows the node, and the ask. The
+// engine's refusal is this command's failure.
+func judgeDirectoriesAsked(args []string, known func(node string) error,
+	ask func(node, by string) (link.HandOverAnswer, error), out io.Writer) error {
+	if len(args) != 1 || args[0] == "" || strings.HasPrefix(args[0], "-") {
+		return errors.New(judgeDirectoriesUsage)
+	}
+	node := args[0]
+	if err := known(node); err != nil {
+		return fmt.Errorf("nothing was asked: %w", err)
+	}
+	answer, err := ask(node, handOverBy())
+	if err != nil {
+		return err
+	}
+	if answer.Refused != "" {
+		return fmt.Errorf("%s refused: %s", node, answer.Refused)
+	}
+	fmt.Fprintf(out, "%s (read-only: nothing on %s was changed)\n", node, node)
+	fmt.Fprintln(out, answer.Said)
+	return nil
+}

cmd/mesh-controller/one_resolution_test.go

@@ -0,0 +1,112 @@
+package main
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+)
+
+// novox/hq issue 237: every line of an act's answer comes from one resolution of the node taken after
+// its write, so the answer agrees with `plan` for the node right after.
+
+func aProviderAndItsConsumer(t *testing.T, open *stores) {
+	t.Helper()
+	register(t, open, catalogue.Manifest{Module: "db", Version: "1",
+		Provides: []catalogue.Offer{{Name: "rows", Scope: catalogue.ScopeNode}}})
+	register(t, open, catalogue.Manifest{Module: "app", Version: "1", Requires: []string{"rows"}})
+}
+
+// twoRivalsAndANote is a node that does not resolve — two modules claim one node seat there — and a
+// module beside them that changes nothing about it.
+func twoRivalsAndANote(t *testing.T, open *stores) {
+	t.Helper()
+	one, two := rivals()
+	register(t, open, one)
+	register(t, open, two)
+	register(t, open, catalogue.Manifest{Module: "notes", Version: "1"})
+}
+
+func TestAnUnassignThatLeavesItsNodeUnresolvedSaysSoOnceInItsAnswer(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	twoRivalsAndANote(t, open)
+	// Straight into the store, as a node that came to this before the act.
+	for _, m := range []string{"rival-one", "rival-two", "notes"} {
+		if _, err := open.inventory.Assign(ctx, "laptop", m); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	said := answered(t, func() error { return assignCommand(ctx, "unassign", []string{"laptop", "notes"}) })
+
+	if _, _, err := planFor(ctx, open, "laptop"); err == nil || !unresolvable(err) {
+		t.Fatalf("laptop resolves with two claimants of one seat: %v", err)
+	}
+	if n := strings.Count(said, "laptop does not resolve now"); n != 1 {
+		t.Errorf("the answer says laptop does not resolve %d times, want once:\n%s", n, said)
+	}
+	if strings.Contains(said, "is left out of the rest of the mesh") {
+		t.Errorf("the answer carries a line from a read that is not its resolution:\n%s", said)
+	}
+}
+
+func TestAnUnassignThatLeavesItsNodeResolvedSaysNothingOfIt(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	aProviderAndItsConsumer(t, open)
+	if _, err := assign(ctx, open, "laptop", "db", "app"); err != nil {
+		t.Fatal(err)
+	}
+	said, err := unassign(ctx, open, "laptop", "app")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, _, err := planFor(ctx, open, "laptop"); err != nil {
+		t.Fatal(err)
+	}
+	if strings.Contains(said, "does not resolve") || strings.Contains(said, "could not be read") {
+		t.Errorf("a node that resolves is said not to:\n%s", said)
+	}
+}
+
+func TestAnAssignThatLeavesItsNodeUnresolvedSaysOnlyThePlansRefusal(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	twoRivalsAndANote(t, open)
+	if _, err := assign(ctx, open, "laptop", "rival-one"); err != nil {
+		t.Fatal(err)
+	}
+	// Kept and not resolvable: a second claimant of the seat, which assignment keeps.
+	said, err := assign(ctx, open, "laptop", "rival-two")
+	if err == nil {
+		t.Fatalf("two claimants of one node seat resolved:\n%s", said)
+	}
+	_, _, planErr := planFor(ctx, open, "laptop")
+	if planErr == nil || planErr.Error() != err.Error() {
+		t.Errorf("the act's refusal is not the plan's right after:\nact:  %v\nplan: %v", err, planErr)
+	}
+	if strings.Contains(said, "now has") {
+		t.Errorf("the answer says a seat is now held on a node that does not resolve:\n%s", said)
+	}
+}
+
+// The other readers of the whole mesh still say a machine they leave out, on standard error (novox/hq
+// issue 188); an act sends it elsewhere.
+func TestAMachineLeftOutIsSaidWhereTheContextSays(t *testing.T) {
+	var buf bytes.Buffer
+	sayLeftOut(leftOutSaidBy(context.Background(), &buf), "laptop", errors.New("why"))
+	if buf.String() != "laptop is left out of the rest of the mesh: it does not resolve: why\n" {
+		t.Errorf("said %q", buf.String())
+	}
+	got := answered(t, func() error {
+		sayLeftOut(context.Background(), "laptop", errors.New("why"))
+		return nil
+	})
+	if !strings.Contains(got, "laptop is left out") {
+		t.Errorf("without an act's writer the line did not reach standard error: %q", got)
+	}
+}

cmd/mesh-controller/outside_not_given_test.go

@@ -0,0 +1,120 @@
+package main
+
+import (
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+)
+
+// An own secret issued outside the mesh that nobody gave is never made (novox/hq issue 401, ADR 0228). Seen on
+// 2026-10-10: the send made a random value for the mounts module's smb-credentials and placed it, and the module read
+// it as a credential given and wrong. The send now makes none, places none, and places a value only once a person
+// gave one — and a value the mesh made for it before is not placed either.
+
+// anAssistant is a module with a secret the mesh makes and one only an outside party issues.
+func anAssistant() catalogue.Manifest {
+	return catalogue.Manifest{Module: "assistant", Version: "1",
+		OwnSecrets: catalogue.OwnSecrets{
+			"password":   {Path: "/var/lib/mesh/assistant/password", Taken: catalogue.TakenAtStart},
+			"vendor-key": {Path: "/var/lib/mesh/assistant/vendor-key", Taken: catalogue.TakenAtStart, IssuedBy: catalogue.IssuedOutside},
+		},
+		Resources: []map[string]any{
+			{"id": "state", "type": "directory", "path": "/var/lib/mesh/assistant", "mode": "0700"},
+		}}
+}
+
+// sentTo composes what a push sends to a machine, on the send path.
+func sentTo(t *testing.T, open *stores, node string) []map[string]any {
+	t.Helper()
+	plan, settings, err := planFor(t.Context(), open, node)
+	if err != nil {
+		t.Fatal(err)
+	}
+	declared, err := declarationFor(t.Context(), open, node, plan, settings)
+	if err != nil {
+		t.Fatalf("the send to %s did not compose: %v", node, err)
+	}
+	return declared.Resources
+}
+
+func placedAt(resources []map[string]any, path string) map[string]any {
+	for _, r := range resources {
+		if r["path"] == path && r["sealed"] != nil {
+			return r
+		}
+	}
+	return nil
+}
+
+func TestTheSendMakesNoValueForAnOutsideSecretNobodyGave(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	register(t, open, anAssistant())
+	if _, err := assign(ctx, open, "laptop", "assistant"); err != nil {
+		t.Fatal(err)
+	}
+
+	sent := sentTo(t, open, "laptop")
+	if placedAt(sent, "/var/lib/mesh/assistant/password") == nil {
+		t.Fatal("the secret the mesh makes was not placed")
+	}
+	if got := placedAt(sent, "/var/lib/mesh/assistant/vendor-key"); got != nil {
+		t.Fatalf("a secret nobody gave was placed: %v", got)
+	}
+	if _, held, err := open.inventory.ModuleSecretIfIssued(ctx, "laptop", "assistant", "vendor-key"); err != nil || held {
+		t.Fatalf("the send made a value for a secret issued outside the mesh (held %v, %v)", held, err)
+	}
+
+	// A value the mesh made before this rule is not one a person gave: it is not placed.
+	if _, err := open.inventory.SecretForModule(ctx, "laptop", "assistant", "vendor-key"); err != nil {
+		t.Fatal(err)
+	}
+	if got := placedAt(sentTo(t, open, "laptop"), "/var/lib/mesh/assistant/vendor-key"); got != nil {
+		t.Fatalf("a value the mesh made for a secret issued outside was placed: %v", got)
+	}
+
+	// Given, it is placed.
+	if err := open.inventory.AcceptSecretForModule(ctx, "laptop", "assistant", "vendor-key", "the vendor's key"); err != nil {
+		t.Fatal(err)
+	}
+	given, ok, err := open.inventory.GivenOwnSecret(ctx, "laptop", "assistant", "vendor-key")
+	if err != nil || !ok || !given.Current {
+		t.Fatalf("the value given is not read as given: %+v %v %v", given, ok, err)
+	}
+	placed := placedAt(sentTo(t, open, "laptop"), "/var/lib/mesh/assistant/vendor-key")
+	if placed == nil || placed["sealed"] != given.Sealed {
+		t.Fatalf("the value given is placed as %v", placed)
+	}
+}
+
+// The read paths answer as the send does: a question about the machine composes without the secret nobody gave, and
+// asking writes nothing.
+func TestAQuestionComposesWithoutAnOutsideSecretNobodyGave(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	register(t, open, anAssistant())
+	if _, err := assign(ctx, open, "laptop", "assistant"); err != nil {
+		t.Fatal(err)
+	}
+	pushedBy(t, open, "laptop") // the mesh's own secret is made by the send
+	plan, settings, err := planFor(ctx, open, "laptop")
+	if err != nil {
+		t.Fatal(err)
+	}
+	gens, err := generators(ctx, open)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, choosing := range []Choosing{Reading, Foreseeing} {
+		got, err := declarationWith(ctx, open, "laptop", plan, settings, gens, choosing)
+		if err != nil {
+			t.Fatalf("%v: %v", choosing, err)
+		}
+		if placedAt(got.Resources, "/var/lib/mesh/assistant/vendor-key") != nil || len(got.foreseen) != 0 {
+			t.Fatalf("%v: a secret nobody gave is composed (foreseen %v)", choosing, got.foreseen)
+		}
+	}
+	if _, held, err := open.inventory.ModuleSecretIfIssued(ctx, "laptop", "assistant", "vendor-key"); err != nil || held {
+		t.Fatalf("a question made a value (held %v, %v)", held, err)
+	}
+}

cmd/mesh-controller/plain_words.go

@@ -81,6 +81,13 @@ var plainWordings = map[string]func(conditions.Observation) words{
 				"It usually catches up by itself.", m, m),
 			Resolved: m + " applied the change"}
 	}),
+	kindApplyFailing: worded(func(o conditions.Observation) words {
+		m := machineOr(o, "a machine")
+		return words{Headline: m + " is not applying its update",
+			Explanation: fmt.Sprintf("%s has refused or only partly applied what the mesh sent it, again and again. "+
+				"The details say what fails.", conditions.Capital(m)),
+			Resolved: m + " applies what it is sent again"}
+	}),
 	"tools-silent": worded(func(o conditions.Observation) words {
 		m := machineOr(o, "a machine")
 		return words{Headline: "Tools on " + m + " are not answering",
@@ -175,6 +182,20 @@ var plainWordings = map[string]func(conditions.Observation) words{
 				"register it, so it was not made.", module, m),
 			Resolved: "Resolved: " + module + " on " + m + " is settled"}
 	}),
+	// The controller or the node-engine kept at the build a machine was last sent, over an older record (novox/hq
+	// issue 201).
+	kindCoreDowngrade: worded(func(o conditions.Observation) words {
+		m := machineOr(o, "a machine")
+		component := idPart(o, 0)
+		if o.Scope != conditions.ScopeCore || !guarded(component) {
+			component = "core component"
+		}
+		return words{Headline: m + " keeps a newer " + component + " than the mesh holds",
+			Needs: fmt.Sprintf("push %s to take the older build, or a newer merge or rebuild moves the record forward.", m),
+			Explanation: fmt.Sprintf("The mesh's record of its own %s is older than the build %s was last sent, so "+
+				"the mesh's sends keep the newer one there rather than put it back.", component, m),
+			Resolved: "Resolved: " + m + " runs the " + component + " the mesh holds"}
+	}),
 	kindBindingKept: worded(func(o conditions.Observation) words {
 		m := machineOr(o, "a machine")
 		return words{Headline: "A module's data source is held on " + m,
@@ -885,6 +906,11 @@ func stalledWords(l stalledLine, o conditions.Observation) (headline, explanatio
 // within its bound (novox/hq issue 438): mesh-delivery holds no delivery of it, so there is nothing to stop, release
 // or close, and no action is offered. The operator's acts are a new commit, which asks the check again, or a look
 // at the build queue, where a check that never ran may still wait.
+//
+// A head whose delivery is held in ready or rejected is said the same way (novox/hq issue 441), and mesh-delivery
+// names that state as data (Held). Its check answered once, so the build queue is the wrong place to look: the step
+// is a recheck of the delivery, named by its id, which asks the check again (novox/hq issue 451). It is advised, not
+// offered as an action, since the controller is not granted the recheck.
 func unansweredWords(l stalledLine, o conditions.Observation) (headline, explanation, resolved, needs string,
 	actions []conditions.Action) {
 	repository, _, _ := strings.Cut(l.ID, "@")
@@ -899,13 +925,23 @@ func unansweredWords(l stalledLine, o conditions.Observation) (headline, explana
 	if d, err := time.ParseDuration(l.Bound); err == nil {
 		limit = ", past its limit of " + humanDuration(d)
 	}
-	which := "Its merge check"
+	check := "merge check"
 	if said := uncheckedWaitWords(l); len(said) > 0 {
-		which = "Its merge check (" + strings.Join(said, ", ") + ")"
+		check = "merge check (" + strings.Join(said, ", ") + ")"
 	}
-	if o.Resolver == conditions.ResolverOperator {
-		needs = "push a new commit to its branch, which asks the check again, or see whether its check still waits " +
-			"in the build queue: mesh-controller.queue."
+	which := "Its " + check
+	switch l.Held {
+	case "ready", "rejected":
+		which = "Its delivery is " + l.Held + ", but on the forge its " + check
+		if o.Resolver == conditions.ResolverOperator {
+			needs = "recheck its delivery, which asks its check again — mesh-delivery.recheck with id " + l.ID +
+				" and why — or push a new commit to its branch, " + FromMeshMCPServer
+		}
+	default:
+		if o.Resolver == conditions.ResolverOperator {
+			needs = "push a new commit to its branch, which asks the check again, or see whether its check still " +
+				"waits in the build queue: mesh-controller.queue."
+		}
 	}
 	return fmt.Sprintf("%s's merge check has not answered %s", pull, long),
 		fmt.Sprintf("%s is open on a branch that requires the merge check. %s was asked and has not answered %s%s. "+

cmd/mesh-controller/plain_words_test.go

@@ -452,3 +452,49 @@ func TestAnUnansweredMergeChecksTimeIsSaidInLocalTime(t *testing.T) {
 		t.Fatalf("a pending check without its time reads %q", o.Explanation)
 	}
 }
+
+// **An unanswered merge check on a ready or rejected delivery is told to recheck it** (novox/hq issue 451):
+// mesh-delivery says such a line too (issue 441) and names the delivery's state as data, `held`. That check already
+// answered once, so the build queue is the wrong place to look; a recheck of the delivery, named by its id, asks the
+// check again. A line with no delivery held keeps the advice of issue 438, and so does a line from a mesh-delivery
+// that does not say `held` yet: the controller never guesses the state from the words.
+func TestAnUnansweredMergeCheckOnAReadyOrRejectedDeliveryOffersARecheck(t *testing.T) {
+	line := func(held string) stalledLine {
+		var l stalledLine
+		raw := `{"id":"novox/mesh-controller@c11222026a3b","number":212,"state":"unanswered",` +
+			`"waiting":["mesh/merge-gate pending since 2026-10-11T00:11:39Z"],"for":"1h1m0s","bound":"1h0m0s",` +
+			`"h2":"none: its delivery is ` + held + `, a state the operator moves — the operator's",` +
+			`"says":"novox/mesh-controller#212 is open on main, which requires the merge check, and its delivery is ` +
+			held + ` here, but on the forge its check has not answered: mesh/merge-gate pending since ` +
+			`2026-10-11T00:11:39Z. The pull request waits on that status and nothing asks it again. A recheck of the ` +
+			`delivery asks its check again, as does a new commit on its branch"`
+		if held != "" {
+			raw += `,"held":"` + held + `"`
+		}
+		if err := json.Unmarshal([]byte(raw+`}`), &l); err != nil {
+			t.Fatal(err)
+		}
+		return l
+	}
+	for _, held := range []string{"ready", "rejected"} {
+		o := stalledObservations([]stalledLine{line(held)})[0]
+		t.Logf("%s: %s\nneeds: %s", held, o.Explanation, o.Needs)
+		if !strings.Contains(o.Needs, "mesh-delivery.recheck") || !strings.Contains(o.Needs, "novox/mesh-controller@c11222026a3b") {
+			t.Fatalf("a %s delivery's unanswered check is not offered its recheck: %q", held, o.Needs)
+		}
+		if strings.Contains(o.Needs, "build queue") || strings.Contains(o.Needs, "mesh-controller.queue") {
+			t.Fatalf("a %s delivery's unanswered check, which answered once, is sent to the build queue: %q", held, o.Needs)
+		}
+		if !strings.Contains(o.Explanation, "Its delivery is "+held) {
+			t.Fatalf("a %s delivery's explanation does not say its state: %q", held, o.Explanation)
+		}
+		if len(o.Actions) != 0 {
+			t.Fatalf("it offers an action the controller is not granted: %+v", o.Actions)
+		}
+	}
+	// No delivery held, or a mesh-delivery that does not say: the advice of issue 438, and no recheck.
+	o := stalledObservations([]stalledLine{line("")})[0]
+	if !strings.Contains(o.Needs, "in the build queue: mesh-controller.queue") || strings.Contains(o.Needs, "recheck") {
+		t.Fatalf("a line with no delivery held says to %q", o.Needs)
+	}
+}

cmd/mesh-controller/plan.go

@@ -292,7 +292,7 @@ func theRestOfTheMesh(ctx context.Context, inv *inventory.Inventory,
 		if err != nil {
 			// Said, not skipped: a machine dropped here offers nothing and holds nothing as far
 			// as every other machine's plan can tell (novox/hq issue 188).
-			fmt.Fprintf(os.Stderr, "%s is left out of the rest of the mesh: it does not resolve: %v\n", o.node.Name, err)
+			sayLeftOut(ctx, o.node.Name, err)
 			continue
 		}
 		firstHeld = append(firstHeld, got.Claims...)
@@ -337,7 +337,7 @@ func theRestOfTheMesh(ctx context.Context, inv *inventory.Inventory,
 			// resolved without its offers, and one that consumes them cannot resolve here by
 			// design — that is not the machine being dropped, it is the view being partial.
 			if exclude == "" {
-				fmt.Fprintf(os.Stderr, "%s is left out of the rest of the mesh: it does not resolve: %v\n", o.node.Name, err)
+				sayLeftOut(ctx, o.node.Name, err)
 			}
 			continue
 		}
@@ -347,6 +347,35 @@ func theRestOfTheMesh(ctx context.Context, inv *inventory.Inventory,
 	return world, nil
 }
 
+// leftOutKey carries where theRestOfTheMesh says a machine it leaves out, for an act that answers with
+// its own resolution instead (novox/hq issue 237).
+type leftOutKey struct{}
+
+// leftOutSaidBy is ctx with theRestOfTheMesh's "left out" lines written to w rather than to standard
+// error.
+//
+// **An act's answer is one resolution taken after its write** (novox/hq issue 237, decided 2026-10-11).
+// `assign` read the whole mesh once before its write — to record the seats held by derivation — and that
+// read said, on standard error, that the node did not resolve for lack of the seat the act was about to
+// give it. The controller seat's verb answers with both streams, so the stale line came last, after the
+// act's own "now has it held", and named as its remedy the assignment just made. An act gives io.Discard
+// here: what the node resolves to after the write is said by its own planFor, and every other machine
+// that does not resolve by blockedElsewhere, both read after the write.
+func leftOutSaidBy(ctx context.Context, w io.Writer) context.Context {
+	return context.WithValue(ctx, leftOutKey{}, w)
+}
+
+// sayLeftOut says that a machine is left out of the rest of the mesh, where ctx says to: standard
+// error unless an act said otherwise. Said, not skipped: a machine dropped there offers nothing and
+// holds nothing as far as every other machine's plan can tell (novox/hq issue 188).
+func sayLeftOut(ctx context.Context, node string, err error) {
+	w, ok := ctx.Value(leftOutKey{}).(io.Writer)
+	if !ok {
+		w = os.Stderr
+	}
+	fmt.Fprintf(w, "%s is left out of the rest of the mesh: it does not resolve: %v\n", node, err)
+}
+
 // declarationFor is everything a node would be sent.
 //
 // One place, because there were three and one of them was written before credentials existed and
@@ -561,6 +590,13 @@ func busCredentialIssued(ctx context.Context, inv *inventory.Inventory, node, mo
 	return nil
 }
 
+// givenUnderAnOldKey is the refusal for a value a person gave — a family's member, or an own secret issued outside
+// the mesh — sealed to a key the machine no longer holds: the mesh cannot make another, so it is given again.
+func givenUnderAnOldKey(module, node, name string) error {
+	return fmt.Errorf("%s on %s holds %q, which was given to the mesh rather than made by it, and %s has "+
+		"since generated a new sealing key. The mesh cannot make another; give it again", module, node, name, node)
+}
+
 // renderingFor is everything a node's declaration is composed with, and the node's record.
 func renderingFor(ctx context.Context, open *stores, node string,
 	plan catalogue.Resolution, settings catalogue.SettingsBy,
@@ -679,10 +715,7 @@ func renderingFor(ctx context.Context, open *stores, node string,
 				}
 				if !g.Current {
 					if choosing == Allocating {
-						return catalogue.Rendering{}, inventory.Node{}, fmt.Errorf(
-							"%s on %s holds %q, which was given to the mesh rather than made by it, and %s has "+
-								"since generated a new sealing key. The mesh cannot make another; give it again",
-							m.Module, node, g.Name, node)
+						return catalogue.Rendering{}, inventory.Node{}, givenUnderAnOldKey(m.Module, node, g.Name)
 					}
 					continue
 				}
@@ -692,7 +725,31 @@ func renderingFor(ctx context.Context, open *stores, node string,
 				needed[m.Module][g.Name] = g.Sealed
 			}
 		}
-		for name := range m.OwnSecrets.Plain() {
+		for name, own := range m.OwnSecrets.Plain() {
+			// **An own secret issued outside the mesh is never made** (novox/hq issue 401, ADR 0228; ADR 0283 for
+			// a family): only a value a person gave is placed. One not given is nothing — no file, and an empty
+			// value where a file of the module names it — so the module can tell it was not given, where a value
+			// the mesh made looked given and wrong. A value the mesh made for it before is not one either.
+			if own.IssuedBy == catalogue.IssuedOutside {
+				g, given, err := inv.GivenOwnSecret(ctx, node, m.Module, name)
+				if err != nil {
+					return catalogue.Rendering{}, inventory.Node{}, err
+				}
+				if !given {
+					continue
+				}
+				if !g.Current {
+					if choosing == Allocating {
+						return catalogue.Rendering{}, inventory.Node{}, givenUnderAnOldKey(m.Module, node, name)
+					}
+					continue
+				}
+				if needed[m.Module] == nil {
+					needed[m.Module] = map[string]string{}
+				}
+				needed[m.Module][name] = g.Sealed
+				continue
+			}
 			// Minted on the send path and only read on every other. Making one is an insert, and
 			// a question that writes is a question that can block against the machine it is about.
 			var sealed string
@@ -1258,6 +1315,14 @@ func planCommand(ctx context.Context, args []string) error {
 		fmt.Printf("%s is assigned nothing\n", args[0])
 		return nil
 	}
+	// Which optional requirements are unbound (novox/hq ADR 0330 §7): beside the document on the
+	// error stream where the answer is the declaration itself, which carries no such field — the
+	// node-engine refuses an envelope key it does not know.
+	if *asDiff || *asJSON {
+		for _, line := range unboundLines(plan) {
+			fmt.Fprintf(os.Stderr, "%s:%s\n", args[0], line)
+		}
+	}
 	if *asDiff {
 		declared, err := declarationFor(ctx, open, args[0], plan, settings)
 		if err != nil {
@@ -1339,6 +1404,9 @@ func planCommand(ctx context.Context, args []string) error {
 	for _, n := range plan.Needs {
 		fmt.Printf("  needs %s from %s, for %s\n", n.Name, n.From, n.For)
 	}
+	for _, line := range unboundLines(plan) {
+		fmt.Println(line)
+	}
 	declared, err := declarationFor(ctx, open, args[0], plan, settings)
 	if err != nil {
 		return err
@@ -1751,28 +1819,43 @@ func (l *unheldLogger) log(node string, unheld []catalogue.Unheld) {
 // which includes every one of a module just assigned — and each now met that was not. Nothing about
 // any other node, and nothing that was already true before the act.
 func unheldChange(shelf map[string]catalogue.Manifest, node string, before, after []string) []string {
-	judge := func(names []string) map[string]catalogue.Unheld {
-		var set []catalogue.Manifest
-		for _, n := range names {
-			if m, known := shelf[n]; known {
-				set = append(set, m)
-			}
+	return unheldChangeTo(shelf, node, before, after, unheldOver(shelf, node, after))
+}
+
+// unheldOver is the node's unmet seat dependencies judged over a set of module names alone.
+func unheldOver(shelf map[string]catalogue.Manifest, node string, names []string) []catalogue.Unheld {
+	var set []catalogue.Manifest
+	for _, n := range names {
+		if m, known := shelf[n]; known {
+			set = append(set, m)
 		}
-		out := map[string]catalogue.Unheld{}
-		for _, u := range catalogue.UnheldDependencies(shelf, node, set, nil) {
-			out[u.Module+" "+u.Seat] = u
-		}
-		return out
 	}
-	was, now := judge(before), judge(after)
+	return catalogue.UnheldDependencies(shelf, node, set, nil)
+}
+
+// unheldChangeTo is unheldChange with the node's dependencies as they now stand given: `now` is what
+// the act's one resolution after its write says is unmet, and `after` the modules that resolution has
+// on the node (novox/hq issue 237). A line about how things stand after the act is never judged from
+// anything else, so it cannot disagree with `plan` for the node.
+func unheldChangeTo(shelf map[string]catalogue.Manifest, node string, before, after []string,
+	now []catalogue.Unheld) []string {
+	key := func(u catalogue.Unheld) string { return u.Module + " " + u.Seat }
+	was := map[string]catalogue.Unheld{}
+	for _, u := range unheldOver(shelf, node, before) {
+		was[key(u)] = u
+	}
+	is := map[string]catalogue.Unheld{}
+	for _, u := range now {
+		is[key(u)] = u
+	}
 	var lines []string
-	for _, k := range sortedNames(now) {
+	for _, k := range sortedNames(is) {
 		if _, already := was[k]; !already {
-			lines = append(lines, "but "+now[k].String())
+			lines = append(lines, "but "+is[k].String())
 		}
 	}
 	for _, k := range sortedNames(was) {
-		if _, still := now[k]; still {
+		if _, still := is[k]; still {
 			continue
 		}
 		u := was[k]

cmd/mesh-controller/plan_ids.go

@@ -0,0 +1,26 @@
+package main
+
+import (
+	"fmt"
+	"regexp"
+)
+
+// planID is every id the mesh gives a plan: a merge's walk or batch (plan-<nanoseconds>) or a release
+// (release-<nanoseconds>).
+var planID = regexp.MustCompile(`^(plan|release)-[0-9]+$`)
+
+// planIDArguments are the arguments of plans that name a plan. wait is among them for when it is declared
+// (novox/hq issue 229); an argument not declared is refused before this is asked.
+var planIDArguments = []string{"id", "wait", "stop", "close", "retry", "go"}
+
+// plainPlanIDs refuses a plans call naming a plan by anything but a plan's id (novox/hq issue 561): checked
+// once, where the call becomes a command line, so nothing else a caller sent reaches a command or the store.
+func plainPlanIDs(given map[string]string) error {
+	for _, arg := range planIDArguments {
+		if id, named := given[arg]; named && !planID.MatchString(id) {
+			return fmt.Errorf("plans %s: %q is not a plan's id (plan-<digits> or release-<digits>, as `plans` "+
+				"lists them); nothing was done", arg, id)
+		}
+	}
+	return nil
+}

cmd/mesh-controller/plan_ids_test.go

@@ -0,0 +1,37 @@
+package main
+
+import (
+	"strings"
+	"testing"
+)
+
+// **A plan's id is checked once, where a call becomes a command line** (novox/hq issue 561): every argument of
+// plans that names a plan is refused unless it is an id the mesh gives a plan, so a quote never reaches a
+// command, nor the store behind it.
+func TestAPlanIdThatIsNoPlansIdIsRefusedBeforeACommandStarts(t *testing.T) {
+	for _, arg := range []string{"id", "stop", "close", "retry", "go"} {
+		for _, bad := range []string{"x' or '1'='1", "plan-1'", "plan-", "plan-1 2", "batch-1", "PLAN-1"} {
+			args := map[string]any{arg: bad}
+			if arg == "stop" || arg == "close" || arg == "go" {
+				args["why"] = "a test"
+			}
+			argv, err := argvFor("plans", args)
+			if err == nil {
+				t.Errorf("plans %s %q was composed: %v", arg, bad, argv)
+				continue
+			}
+			if !strings.Contains(err.Error(), "is not a plan's id") {
+				t.Errorf("plans %s %q was refused for another reason: %v", arg, bad, err)
+			}
+		}
+		for _, good := range []string{"plan-1791813626034291775", "release-1791811938267404408"} {
+			args := map[string]any{arg: good}
+			if arg == "stop" || arg == "close" || arg == "go" {
+				args["why"] = "a test"
+			}
+			if _, err := argvFor("plans", args); err != nil {
+				t.Errorf("plans %s %q was refused: %v", arg, good, err)
+			}
+		}
+	}
+}

cmd/mesh-controller/plan_retry.go

@@ -251,6 +251,16 @@ func resumed(p *inventory.Plan, why string) {
 	if p.State == inventory.PlanFailed && len(failedIn(*p)) == 0 {
 		p.State = inventory.PlanBuilding
 		p.Note = why
+		goesOnAgain(p)
+	}
+}
+
+// goesOnAgain clears a stop from a walk that walks again: a stop said why the walk ended, and a walk resumed has
+// not ended. Kept, it would end a retried walk that fails again as stopped, not failed (novox/hq ADR 0308
+// decision 1), and keep the search for the merge that brought the failure from running (searchAfterFailures).
+func goesOnAgain(p *inventory.Plan) {
+	if p.Delivery != nil {
+		p.Delivery.Stopped, p.Delivery.StoppedWhy = "", ""
 	}
 }
 
@@ -460,6 +470,7 @@ func retryRollouts(ctx context.Context, open *stores, p *inventory.Plan) (string
 		said = append(said, m+" to "+strings.Join(again, ", "))
 	}
 	p.State = inventory.PlanRolling
+	goesOnAgain(p)
 	p.Note = fmt.Sprintf("tier %d retried by hand; sent %s first again", p.Tier, strings.Join(said, "; "))
 	if err := open.inventory.SavePlan(ctx, p); err != nil {
 		return "", err
@@ -525,6 +536,7 @@ func retryTierWhole(ctx context.Context, open *stores, p *inventory.Plan, again
 	}
 	if p.State == inventory.PlanFailed && len(failedIn(*p)) == 0 {
 		p.State = inventory.PlanBuilding
+		goesOnAgain(p)
 		p.Note = fmt.Sprintf("tier %d retried by hand: %s asked again; %s sent again with the tier", p.Tier,
 			strings.Join(again, ", "), orNone(strings.Join(resent, ", ")))
 	}

cmd/mesh-controller/plans_follow.go

@@ -0,0 +1,158 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// Following a plan (novox/hq issue 229): `plans wait <id>` holds its answer until the plan moves, reaches its
+// next tier or ends, or until its bound passes, and says which. Before it, an agent following a rollout had
+// `plans` answer once, in prose, and wrote a loop of its own round the mesh's tools to be told the plan moved.
+//
+// **No wait is longer than a call is answered within** (link.LongestAnswer, inside the console's thirty
+// seconds): a longer one would answer "still running" and leave its caller to ask `calls` — the loop again.
+// So a caller following a plan to its end asks again; each call answers the moment the plan moves.
+
+// maxPlanWait is the longest bound a wait takes, and the bound when none is given: what a call is answered
+// within, less the time a verb's command takes to start and read the store.
+var maxPlanWait = link.LongestAnswer - planWaitStart
+
+// planWaitStart is what the verb's window allows beyond the bound: starting the command and opening the stores.
+// A store slow enough to push the read and the answer past it degrades as any long call does: the caller is
+// answered that the call is still running, and `calls` with its id says what came of it.
+const planWaitStart = 5 * time.Second
+
+// planWaitEvery is how often a wait reads the plan again.
+const planWaitEvery = time.Second
+
+// The things a wait waits until.
+var planWaitUntil = []string{"moved", "tier", "done"}
+
+// planWaitAsked checks what a wait is asked for: until (moved when empty) and a bound (a duration, or a number
+// of seconds; maxPlanWait when empty).
+func planWaitAsked(until, bound string) (string, time.Duration, error) {
+	if until == "" {
+		until = "moved"
+	}
+	known := false
+	for _, u := range planWaitUntil {
+		known = known || u == until
+	}
+	if !known {
+		return "", 0, fmt.Errorf("a wait is until %s, not %q", strings.Join(planWaitUntil, ", "), until)
+	}
+	d := maxPlanWait
+	if bound = strings.TrimSpace(bound); bound != "" {
+		var err error
+		if secs, isNumber := strconv.Atoi(bound); isNumber == nil {
+			d = time.Duration(secs) * time.Second
+		} else if d, err = time.ParseDuration(bound); err != nil {
+			return "", 0, fmt.Errorf("the bound %q is not a duration (such as 20s) or a number of seconds", bound)
+		}
+		if d <= 0 || d > maxPlanWait {
+			return "", 0, fmt.Errorf("the bound is at most %s, the longest a call is answered within; %s was asked "+
+				"— to follow a plan longer, ask again: each call answers the moment the plan moves", maxPlanWait, d)
+		}
+	}
+	return until, d, nil
+}
+
+// planEnded is a plan that will not move again: done, failed or superseded. A batch being assembled is not one.
+func planEnded(p inventory.Plan) bool { return !p.Open() && !p.Batch() }
+
+// waitOnPlan reads the plan until what it waits for happens or the bound passes, and answers the plan as last
+// read and what ended the wait: moved (any save of it), tier (its tier changed), done (it ended — which ends
+// every wait, since nothing comes after it), or bound. Moved and tier are judged against the plan as first read.
+func waitOnPlan(ctx context.Context, read func(context.Context) (inventory.Plan, error), until string,
+	bound, every time.Duration) (inventory.Plan, string, error) {
+	first, err := read(ctx)
+	if err != nil {
+		return inventory.Plan{}, "", err
+	}
+	if planEnded(first) {
+		return first, "done", nil
+	}
+	deadline := time.Now().Add(bound)
+	tick := time.NewTicker(every)
+	defer tick.Stop()
+	last := first
+	for {
+		select {
+		case <-ctx.Done():
+			return last, "", ctx.Err()
+		case <-tick.C:
+		}
+		if !time.Now().Before(deadline) {
+			return last, "bound", nil
+		}
+		p, err := read(ctx)
+		if err != nil {
+			return last, "", err
+		}
+		last = p
+		switch {
+		case planEnded(p):
+			return p, "done", nil
+		case until == "moved" && p.Revision != first.Revision:
+			return p, "moved", nil
+		case until == "tier" && p.Tier != first.Tier:
+			return p, "tier", nil
+		}
+	}
+}
+
+// planWaited is what `plans wait` answers: the plan, what ended the wait, and the line a person reads (`text`,
+// which the verb answers as its output and not again in the data).
+type planWaited struct {
+	// Came is what ended the wait: moved, tier, done, or bound when nothing did.
+	Came   string     `json:"came"`
+	Until  string     `json:"until"`
+	Waited string     `json:"waited"`
+	Plan   planStatus `json:"plan"`
+	// Revision is the plan's as read: a caller asking again with the same plan sees whether it moved since.
+	Revision int64  `json:"revision"`
+	Text     string `json:"text"`
+}
+
+func planWaitedDoc(p inventory.Plan, st planStatus, until, came string, waited time.Duration, line string) planWaited {
+	said := map[string]string{
+		"moved": "moved", "tier": "reached another tier", "done": "ended",
+		"bound": "did not " + map[string]string{"moved": "move", "tier": "reach another tier", "done": "end"}[until],
+	}[came]
+	text := fmt.Sprintf("%s %s in %s (waited until %s)\n%s — %s\n", p.ID, said, waited.Round(time.Second), until,
+		p.ID, line)
+	return planWaited{Came: came, Until: until, Waited: waited.Round(time.Millisecond).String(), Plan: st,
+		Revision: p.Revision, Text: text}
+}
+
+// planWaitCommand is `plans wait <id>`: the plan followed until it moves, or the bound passes.
+func planWaitCommand(ctx context.Context, inv *inventory.Inventory, id, untilAsked, boundAsked string) error {
+	until, bound, err := planWaitAsked(untilAsked, boundAsked)
+	if err != nil {
+		return err
+	}
+	began := time.Now()
+	p, came, err := waitOnPlan(ctx, func(ctx context.Context) (inventory.Plan, error) {
+		return inv.PlanByID(ctx, id)
+	}, until, bound, planWaitEvery)
+	if err != nil {
+		return err
+	}
+	// Said as `plans <id>` says its first line, and as `status` says the plan.
+	now, one := time.Now(), []inventory.Plan{p}
+	bounds, pause := readTierBounds(ctx, inv, now), buildSeatPause(ctx, inv, one)
+	line := planLineSaid(p, now, pause, bounds.of(p.Repository), func(module string) []string {
+		on, _ := inv.Running(ctx, module)
+		return on
+	}, waitsOf(ctx, inv, one))
+	doc := planWaitedDoc(p, planStatuses(one, now, pause, bounds)[0], until, came, now.Sub(began), line)
+	return json.NewEncoder(os.Stdout).Encode(doc)
+}

cmd/mesh-controller/plans_follow_test.go

@@ -0,0 +1,196 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// A plan as the store would answer it at each read: the reads are counted, and each answers the next.
+type planReads struct {
+	plans []inventory.Plan
+	n     int
+}
+
+func (r *planReads) read(context.Context) (inventory.Plan, error) {
+	p := r.plans[min(r.n, len(r.plans)-1)]
+	r.n++
+	return p, nil
+}
+
+func followedPlan(rev int64, state string, tier int) inventory.Plan {
+	return inventory.Plan{ID: "plan-1", Repository: "novox/x", Commit: "abc", State: state, Tier: tier,
+		Tiers: [][]string{{"a"}, {"b"}}, Revision: rev}
+}
+
+// **`plans` waits for a plan, and says what ended the wait** (novox/hq issue 229): an agent following a
+// rollout is told when the plan moved, reached its next tier or ended, or that the bound passed — in one
+// call, without a loop of its own.
+func TestAWaitForAPlanEndsWhenWhatItWaitsForHappens(t *testing.T) {
+	cases := []struct {
+		name  string
+		until string
+		reads []inventory.Plan
+		came  string
+		times int
+	}{
+		{"moved: any save", "moved", []inventory.Plan{
+			followedPlan(1, inventory.PlanBuilding, 0), followedPlan(1, inventory.PlanBuilding, 0),
+			followedPlan(2, inventory.PlanBuilding, 0)}, "moved", 3},
+		{"tier: a save inside the tier is not enough", "tier", []inventory.Plan{
+			followedPlan(1, inventory.PlanBuilding, 0), followedPlan(2, inventory.PlanBuilding, 0),
+			followedPlan(3, inventory.PlanRolling, 1)}, "tier", 3},
+		{"tier: a plan that ended has no next tier to wait for", "tier", []inventory.Plan{
+			followedPlan(1, inventory.PlanBuilding, 0), followedPlan(2, inventory.PlanFailed, 0)}, "done", 2},
+		{"done: a new tier is not the end", "done", []inventory.Plan{
+			followedPlan(1, inventory.PlanBuilding, 0), followedPlan(2, inventory.PlanRolling, 1),
+			followedPlan(3, inventory.PlanDone, 1)}, "done", 3},
+		{"done: a plan already ended answers at once", "done", []inventory.Plan{
+			followedPlan(4, inventory.PlanSuperseded, 1)}, "done", 1},
+		{"the bound passes", "moved", []inventory.Plan{followedPlan(1, inventory.PlanBuilding, 0)}, "bound", -1},
+	}
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			r := &planReads{plans: c.reads}
+			p, came, err := waitOnPlan(context.Background(), r.read, c.until, 50*time.Millisecond, time.Millisecond)
+			if err != nil {
+				t.Fatal(err)
+			}
+			if came != c.came {
+				t.Fatalf("the wait ended as %q, want %q", came, c.came)
+			}
+			if c.times > 0 && r.n != c.times {
+				t.Errorf("read the plan %d times, want %d: it answered before or after what it waited for", r.n, c.times)
+			}
+			if want := c.reads[min(r.n, len(c.reads))-1]; p.Revision != want.Revision {
+				t.Errorf("answered revision %d, not the plan as it was last read (%d)", p.Revision, want.Revision)
+			}
+		})
+	}
+}
+
+// What a wait is asked for is checked before anything is read: what it waits until, and a bound no longer than
+// a call is answered within.
+func TestAWaitIsRefusedWhatItCannotDo(t *testing.T) {
+	for _, bad := range []struct{ until, bound string }{{"landed", ""}, {"", "1h"}, {"", "-3s"}, {"", "soon"}} {
+		if _, _, err := planWaitAsked(bad.until, bad.bound); err == nil {
+			t.Errorf("until %q, bound %q was taken", bad.until, bad.bound)
+		}
+	}
+	until, bound, err := planWaitAsked("", "")
+	if err != nil || until != "moved" || bound != maxPlanWait {
+		t.Fatalf("the defaults are %q %s %v, want moved and %s", until, bound, err, maxPlanWait)
+	}
+	if _, bound, _ := planWaitAsked("tier", "12"); bound != 12*time.Second {
+		t.Errorf("a bare number is seconds; read %s", bound)
+	}
+}
+
+// **The answer is data, with its prose as a field beside it** (novox/hq issue 229): the verb's `answer` carries
+// the plan and what ended the wait, and its output is the line a person reads — never JSON inside a string.
+func TestAWaitForAPlanAnswersAsData(t *testing.T) {
+	p := followedPlan(7, inventory.PlanRolling, 1)
+	st := planStatuses([]inventory.Plan{p}, time.Now(), pauseView{}, tierBounds{})[0]
+	doc := planWaitedDoc(p, st, "tier", "tier", 3*time.Second, "rolling, tier 2 of 2")
+	stdout, _ := json.Marshal(doc)
+	a := answerOf([]string{"plans", "wait", "plan-1"}, stdout, "", true)
+	data, ok := a.Answer.(map[string]any)
+	if !ok {
+		t.Fatalf("the answer is not data: %v", a.Answer)
+	}
+	if data["came"] != "tier" || data["revision"] != float64(7) {
+		t.Errorf("the data does not say what ended the wait: %v", data)
+	}
+	if plan, _ := data["plan"].(map[string]any); plan["state"] != "rolling" || plan["tier"] != float64(1) {
+		t.Errorf("the data does not carry the plan: %v", data["plan"])
+	}
+	if _, text := data["text"]; text {
+		t.Errorf("the prose is in the data too: %v", data)
+	}
+	if strings.Contains(a.Output, "{") || !strings.Contains(a.Output, "plan-1") || !strings.Contains(a.Output, "tier") {
+		t.Errorf("the output is not the line a person reads: %q", a.Output)
+	}
+}
+
+// The verb composes the wait, and asks for a window as long as its bound.
+func TestThePlansVerbComposesAWait(t *testing.T) {
+	argv, err := argvFor("plans", map[string]any{"wait": "plan-1", "until": "done", "bound": "15s"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got := strings.Join(argv, " "); got != "plans wait plan-1 --until done --bound 15s" {
+		t.Fatalf("composed %q", got)
+	}
+	if _, err := argvFor("plans", map[string]any{"until": "done"}); err == nil {
+		t.Error("until without wait was taken")
+	}
+	if _, err := argvFor("plans", map[string]any{"wait": "plan-1", "bound": "1h"}); err == nil {
+		t.Error("a bound past what a call can wait was taken")
+	}
+}
+
+// Live, with the store: `plans wait` run as the verb runs it answers when the plan reaches its next tier, as
+// data, and says the bound passed when nothing moved (novox/hq issue 229).
+func TestAPlanFollowedFromTheStoreAnswersWhenItMoves(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	now := time.Now().UTC()
+	walk := inventory.Plan{ID: "plan-229", Repository: "novox/mesh-catalog", Branch: "main", Commit: "c229c229",
+		Created: now, State: inventory.PlanBuilding, Tiers: [][]string{{"a"}, {"b"}},
+		Modules: map[string]*inventory.PlanModule{"a": {}, "b": {}}}
+	if err := open.inventory.SavePlan(ctx, &walk); err != nil {
+		t.Fatal(err)
+	}
+	moved := make(chan error, 1)
+	go func() {
+		time.Sleep(1500 * time.Millisecond)
+		p, err := open.inventory.PlanByID(ctx, walk.ID)
+		if err == nil {
+			p.Tier, p.State = 1, inventory.PlanRolling
+			err = open.inventory.SavePlan(ctx, &p)
+		}
+		moved <- err
+	}()
+	began := time.Now()
+	var got planWaited
+	out := printed(t, func() error {
+		return plansCommand(ctx, []string{"wait", walk.ID, "--until", "tier", "--bound", "15s"})
+	})
+	if err := <-moved; err != nil {
+		t.Fatal(err)
+	}
+	if err := json.Unmarshal([]byte(out), &got); err != nil {
+		t.Fatalf("plans wait did not answer data: %v: %q", err, out)
+	}
+	if got.Came != "tier" || got.Plan.Tier != 1 || got.Plan.State != inventory.PlanRolling {
+		t.Fatalf("the wait answered %+v", got)
+	}
+	if waited := time.Since(began); waited > 10*time.Second {
+		t.Errorf("it answered after %s, not when the plan moved", waited)
+	}
+	out = printed(t, func() error {
+		return plansCommand(ctx, []string{"wait", walk.ID, "--bound", "2"})
+	})
+	if err := json.Unmarshal([]byte(out), &got); err != nil || got.Came != "bound" || got.Until != "moved" {
+		t.Fatalf("a plan that did not move answered %+v (%v)", got, err)
+	}
+}
+
+// The verb's schema says the longest bound in words, and the words are the value (review 75 on #266): the
+// catalogue cannot read maxPlanWait, so this holds them together.
+func TestThePlansSchemaSaysTheLongestBoundThereIs(t *testing.T) {
+	v, ok := controllerVerb("plans")
+	if !ok {
+		t.Fatal("no plans verb")
+	}
+	props, _ := v.Input["properties"].(map[string]any)
+	bound, _ := props["bound"].(map[string]any)
+	said, _ := bound["description"].(string)
+	if !strings.Contains(said, maxPlanWait.String()+", the default, is the longest") {
+		t.Fatalf("the schema says %q; the longest bound is %s", said, maxPlanWait)
+	}
+}

cmd/mesh-controller/proposals.go

@@ -591,7 +591,7 @@ func proposeCommand(ctx context.Context, module, node, valuesArg string, clear,
 			return err
 		},
 		routerHere: routerHereIn(open.inventory),
-		grantHeld:  grantHeldIn(open),
+		grantHeld:  grantHeldIn(open, conn),
 		routerRecord: func(ctx context.Context, id string) (string, error) {
 			bucket, err := asksRecords(ctx, open.inventory)
 			if err != nil || bucket == "" {

cmd/mesh-controller/push.go

@@ -249,7 +249,7 @@ func serve(ctx context.Context) (err error) {
 	// (novox/hq to-be 45 §9).
 	checkEvents = bus
 	// And every walk this controller keeps in a new state, for the delivery it walks (novox/hq ADR 0239).
-	inventory.PlanSaved = func(p inventory.Plan) { sayPlanMoved(ctx, bus, p) }
+	inventory.PlanSaved = func(_ *inventory.Inventory, p inventory.Plan) { sayPlanMoved(ctx, bus, open.inventory, p) }
 	if err := server.Checks(following{open}); err != nil {
 		return err
 	}
@@ -1027,6 +1027,9 @@ func (b overTheBus) declare(ctx context.Context, s readyNode, body []byte) (stri
 	if err != nil {
 		return "", err
 	}
+	// A send that carried the mesh's record of the controller and the node-engine — a person's push included —
+	// ends the condition of one kept over it (novox/hq issue 201).
+	settleCoreDowngrades(ctx, b.open.inventory, s.node, s.declared.Builds)
 	if len(s.declared.Bindings) > 0 {
 		// And where it bound each consumer of a provision that keeps its data (novox/hq ADR 0232):
 		// what the next resolution keeps it at. On the same outliving context as the send's record.
@@ -1084,42 +1087,58 @@ func brokerFirst(names []string, holder string, behind bool) []string {
 // send anywhere, and a module running there always put it in its first wave. A digest of the list
 // last sent is kept for this (ADR 0043: the list is composed on each push, never kept itself).
 func brokerBehind(ctx context.Context, open *stores, names []string) (string, bool, error) {
+	s, err := brokerListState(ctx, open, names)
+	return s.Machine, s.Behind, err
+}
+
+// brokerListState is brokerBehind with why the list could not be composed, when it could not: the plan's own
+// reason, which a remedy names rather than a push that would fail on it (the review of hq issue 353).
+func brokerListState(ctx context.Context, open *stores, names []string) (busListState, error) {
 	inv := open.inventory
 	holders, err := seatHolders(ctx, inv)
 	if err != nil {
-		return "", false, err
+		return busListState{}, err
 	}
 	h, held := holders[theBrokerSeat]
 	if !held || h.Node == "" {
-		return "", false, nil
+		return busListState{}, nil
 	}
 	shelf, err := inv.Catalogue(ctx)
 	if err != nil {
-		return "", false, err
+		return busListState{}, err
 	}
 	if m, known := shelf[h.Module]; !known || m.BusUsers == "" {
 		// A holder that is sent no user list carries no grant: nothing to send first.
-		return "", false, nil
+		return busListState{}, nil
 	}
 	for _, n := range names {
 		if n == h.Node {
-			return h.Node, false, nil
+			return busListState{Machine: h.Node}, nil
 		}
 	}
+	// **What cannot be worked out is behind** (the review of hq issue 353). The list it would be sent cannot be
+	// composed, so whether it carries the grants a send relies on is not known; it is taken as behind, so a push
+	// sends that machine first and says why it cannot (`plan` says it too), and a rollout that needs the list
+	// refuses rather than sending code whose grants the bus may not hold. It said "not behind" until then: a
+	// send went ahead as if the bus held a list nobody could compose.
+	list, composeErr := "", error(nil)
 	plan, _, err := planFor(ctx, open, h.Node)
 	if err != nil {
-		// It cannot be worked out: sending it would refuse the whole send, and `plan` says why.
-		return h.Node, false, nil
-	}
-	list, _, err := busUserList(ctx, inv, plan.Modules)
-	if err != nil {
-		return h.Node, false, nil
+		composeErr = err
+	} else if list, _, err = busUserList(ctx, inv, plan.Modules); err != nil {
+		composeErr = err
 	}
 	sent, err := inv.SentBusUsers(ctx, h.Node)
 	if err != nil {
-		return "", false, err
+		return busListState{}, err
 	}
-	return h.Node, userListBehind(list, sent), nil
+	return busListState{Machine: h.Node, Behind: listBehind(list, composeErr, sent), Uncomposed: composeErr}, nil
+}
+
+// listBehind is whether the bus's machine is behind: the list composed now is not the one last sent, or it
+// could not be composed at all — not known is behind, never "not behind".
+func listBehind(list string, composeErr error, sentDigest string) bool {
+	return composeErr != nil || userListBehind(list, sentDigest)
 }
 
 // userListBehind is whether the user list composed now is not the one last sent, by its digest. An

cmd/mesh-controller/queue.go

@@ -8,12 +8,12 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"regexp"
 	"sort"
 	"strings"
 	"time"
 
 	"github.com/nats-io/nats.go"
-	"github.com/nats-io/nats.go/jetstream"
 
 	"github.com/novox/mesh-controller/internal/broker"
 	"github.com/novox/mesh-controller/internal/inventory"
@@ -67,18 +67,117 @@ func listQueue(ctx context.Context, args []string, w io.Writer) error {
 	if err != nil {
 		return err
 	}
+	now := time.Now()
 	if *asJSON {
-		body, err := json.MarshalIndent(q, "", "  ")
+		body, err := json.MarshalIndent(queueAnswerOf(q, now), "", "  ")
 		if err != nil {
 			return err
 		}
 		fmt.Fprintln(w, string(body))
 		return nil
 	}
-	fmt.Fprint(w, queueText(q, time.Now()))
+	fmt.Fprint(w, queueText(q, now))
 	return nil
 }
 
+// keepingTheQueueInOrder runs the build queue's passes while this controller acts (novox/hq issue 558):
+// the one process that puts the queue in order, so no two passes pause and resume it over each other.
+// The build seat is read from the catalogue at most every half minute.
+func keepingTheQueueInOrder(ctx context.Context, open *stores, js *broker.JetStream) {
+	if js == nil {
+		return
+	}
+	seat, readAt := link.TheBuildMachine, time.Time{}
+	seatNow := func() string {
+		if time.Since(readAt) < watchEvery {
+			return seat
+		}
+		if entries, err := open.inventory.Catalogued(ctx); err == nil {
+			seat, readAt = buildSeatAmong(entries), time.Now()
+		} else {
+			fmt.Printf("the build seat is read as %s: the catalogue cannot be read: %v\n", seat, err)
+		}
+		return seat
+	}
+	link.KeepingInOrder(ctx, js, seatNow, link.Holding, func(format string, args ...any) {
+		fmt.Printf(format+"\n", args...)
+	})
+}
+
+// queueAnswer is the queue as data (novox/hq issue 455): what a caller reads to say how far back an ask
+// waits — "waiting in the build queue behind 2" — which the table alone could not tell it. Text is the
+// table, written from the same read: the verb answers it as its output and the rest as its answer, so the
+// two never disagree.
+type queueAnswer struct {
+	Seat       string         `json:"seat"`
+	Waiting    int            `json:"waiting"`
+	InFlight   int            `json:"in-flight"`
+	Dead       int            `json:"dead"`
+	MaxDeliver int            `json:"max-deliver"`
+	Asks       []queuedAnswer `json:"asks"`
+	Text       string         `json:"text"`
+}
+
+// queuedAnswer is one ask as data. Never what the request carries beyond its source — not `held`, every
+// artifact the mesh has built, nor a check's checkouts beside it.
+type queuedAnswer struct {
+	ID    string `json:"id"`
+	State string `json:"state"`
+	// Kind is "delivery" for a build a walk waits for, "check" for a pull request's check and any ask
+	// whose kind cannot be told (link.KindOf, novox/hq issue 558).
+	Kind       string `json:"kind"`
+	Repository string `json:"repository"`
+	Path       string `json:"path,omitempty"`
+	Ref        string `json:"ref,omitempty"`
+	// Commit is the ref when it names a commit; empty when the ask follows a branch or the default.
+	Commit string `json:"commit,omitempty"`
+	// Machine is the one building an ask in flight; WasOn the one that started it and handed it back.
+	Machine string    `json:"machine,omitempty"`
+	WasOn   string    `json:"was-on,omitempty"`
+	AskedAt time.Time `json:"asked-at,omitzero"`
+	// Since is when the ask came to its state: its start on the machine for one in flight that a
+	// machine said it started, otherwise when it was asked.
+	Since time.Time `json:"since,omitzero"`
+	// Position is its place among the waiting, 1 being handed out next; 0 for an ask not waiting.
+	Position int    `json:"position,omitempty"`
+	Seq      uint64 `json:"seq"`
+}
+
+// aCommitRef is a ref that names a commit by its full hash (SHA-1 or SHA-256).
+var aCommitRef = regexp.MustCompile(`^(?:[0-9a-f]{40}|[0-9a-f]{64})$`)
+
+// queueAnswerOf is the queue as data, in the table's order: in flight, the waiting from the next one to
+// be handed out, then the dead. A pure function of one read (novox/hq issue 455).
+func queueAnswerOf(q link.Queue, now time.Time) queueAnswer {
+	waiting, running, dead := q.Of(link.AskWaiting), q.Of(link.AskInFlight), q.Of(link.AskDead)
+	out := queueAnswer{Seat: q.Seat, Waiting: len(waiting), InFlight: len(running), Dead: len(dead),
+		MaxDeliver: q.MaxDeliver, Asks: []queuedAnswer{}, Text: queueText(q, now)}
+	one := func(a link.QueuedAsk, position int) queuedAnswer {
+		kind := link.KindOf(a.Request)
+		since := a.AskedAt
+		if a.State == link.AskInFlight && a.On != "" && !a.Started.IsZero() {
+			since = a.Started
+		}
+		commit := ""
+		if aCommitRef.MatchString(a.Ref) {
+			commit = a.Ref
+		}
+		return queuedAnswer{ID: a.ID, State: a.State, Kind: kind, Repository: link.WithoutPassword(a.Repository), Path: a.Path,
+			Ref: a.Ref, Commit: commit, Machine: a.On, WasOn: a.Was, AskedAt: a.AskedAt, Since: since,
+			Position: position, Seq: a.Seq}
+	}
+	for _, a := range running {
+		out.Asks = append(out.Asks, one(a, 0))
+	}
+	for i, a := range waiting {
+		out.Asks = append(out.Asks, one(a, i+1))
+	}
+	for _, a := range dead {
+		out.Asks = append(out.Asks, one(a, 0))
+	}
+	return out
+}
+
 // queueText is the queue as a person reads it: a summary line, then each kind in queue order.
 // Never what an ask carries as `held` — that is every artifact the mesh has built.
 func queueText(q link.Queue, now time.Time) string {
@@ -92,7 +191,7 @@ func queueText(q link.Queue, now time.Time) string {
 		return "asked " + now.Sub(t).Round(time.Second).String() + " ago"
 	}
 	what := func(a link.QueuedAsk) string {
-		s := a.Repository
+		s := link.WithoutPassword(a.Repository)
 		if a.Path != "" {
 			s += " at " + a.Path
 		}
@@ -111,19 +210,20 @@ func queueText(q link.Queue, now time.Time) string {
 			case a.Was != "":
 				where = fmt.Sprintf("handed back by %s, to be handed out again", a.Was)
 			}
-			fmt.Fprintf(&b, "  %-26s %s — %s, %s (seq %d)\n", a.ID, what(a), where, ago(a.AskedAt), a.Seq)
+			fmt.Fprintf(&b, "  %-26s %-8s %s — %s, %s (seq %d)\n", a.ID, link.KindOf(a.Request), what(a), where,
+				ago(a.AskedAt), a.Seq)
 		}
 	}
 	if len(waiting) > 0 {
-		fmt.Fprintln(&b, "\nwaiting:")
+		fmt.Fprintln(&b, "\nwaiting, in the order they are handed out:")
 		for _, a := range waiting {
-			fmt.Fprintf(&b, "  %-26s %s — %s (seq %d)\n", a.ID, what(a), ago(a.AskedAt), a.Seq)
+			fmt.Fprintf(&b, "  %-26s %-8s %s — %s (seq %d)\n", a.ID, link.KindOf(a.Request), what(a), ago(a.AskedAt), a.Seq)
 		}
 	}
 	if len(dead) > 0 {
 		fmt.Fprintf(&b, "\ndead — handed out as often as the worker allows (%d) and never settled, still held:\n", q.MaxDeliver)
 		for _, a := range dead {
-			fmt.Fprintf(&b, "  %-26s %s — %s (seq %d)\n", a.ID, what(a), ago(a.AskedAt), a.Seq)
+			fmt.Fprintf(&b, "  %-26s %-8s %s — %s (seq %d)\n", a.ID, link.KindOf(a.Request), what(a), ago(a.AskedAt), a.Seq)
 		}
 	}
 	switch {
@@ -197,6 +297,15 @@ func cancelAsk(ctx context.Context, js *broker.JetStream, open *stores, seat str
 		}
 	}
 	worker, _ := broker.HolderConsumerFor("", "", broker.DeclaredSeat{Name: seat, Accepts: []string{"build"}})
+	// **Where it waits now** (novox/hq issue 558): moved into order since it was read, a waiting ask has a
+	// later sequence, and the worker handing out what was behind its old one is not it being taken.
+	if ask.State == link.AskWaiting {
+		if q, err := link.ReadQueue(ctx, js, seat); err == nil {
+			if now, ok := q.Find(ask.ID); ok && now.State == link.AskWaiting {
+				ask.Seq = now.Seq
+			}
+		}
+	}
 	switch ask.State {
 	case link.AskWaiting:
 		if taken, err := takenSince(js, worker, ask.Seq); err != nil {
@@ -218,14 +327,25 @@ func cancelAsk(ctx context.Context, js *broker.JetStream, open *stores, seat str
 				"ends it there", ask.ID, started, ask.ID)
 		}
 	}
-	if err := js.Context().DeleteMsg(worker.Stream, ask.Seq); err != nil && !errors.Is(err, nats.ErrMsgNotFound) &&
-		!errors.Is(err, jetstream.ErrMsgNotFound) && !strings.Contains(err.Error(), "no message found") {
+	// Found by its id when it was moved into order since it was read (novox/hq issue 558).
+	removed, err := link.DeleteAsk(ctx, js, seat, ask)
+	if err != nil {
 		return "", fmt.Errorf("%s is marked cancelled and could not be deleted from the queue (seq %d): %w — a "+
 			"holder taking it ends it as cancelled", ask.ID, ask.Seq, err)
 	}
 	recordCancelled(ctx, open, ask)
-	return fmt.Sprintf("cancelled %s (%s, %s): deleted from the %s queue and recorded failed, %s — a plan "+
-		"that asked for it fails with that", ask.ID, ask.Repository, ask.State, seat, link.CancelledByHand), nil
+	return cancelSaid(ask, seat, removed), nil
+}
+
+// cancelSaid is what a cancel says: deleted from the queue only when it was.
+func cancelSaid(ask link.QueuedAsk, seat string, removed uint64) string {
+	where := fmt.Sprintf("deleted from the %s queue", seat)
+	if removed == 0 {
+		where = fmt.Sprintf("no longer in the %s queue to delete, and marked cancelled, so a holder taking it "+
+			"ends it", seat)
+	}
+	return fmt.Sprintf("cancelled %s (%s, %s): %s and recorded failed, %s — a plan "+
+		"that asked for it fails with that", ask.ID, ask.Repository, ask.State, where, link.CancelledByHand)
 }
 
 // holderLooks is how long a cancel waits for a holder that took the ask before the mark to say it

cmd/mesh-controller/queue_answer_test.go

@@ -0,0 +1,157 @@
+package main
+
+import (
+	"encoding/json"
+	"reflect"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// The queue answers as data as well as text (novox/hq issue 455): each ask's repository, commit, kind,
+// machine, since and position among the waiting, read from the same queue the table is written from.
+
+const aCommit = "0123456789abcdef0123456789abcdef01234567"
+
+func aQueueOfEachKind(now time.Time) link.Queue {
+	asked := now.Add(-5 * time.Minute)
+	started := now.Add(-2 * time.Minute)
+	return link.Queue{Seat: link.TheBuildMachine, Delivered: 2, AckPending: 1, MaxDeliver: 5, Asks: []link.QueuedAsk{
+		{Seq: 1, ID: "build-dead", Repository: "ssh://forge/novox/x", AskedAt: asked, State: link.AskDead},
+		{Seq: 2, ID: "build-running", Repository: "ssh://forge/novox/mesh-host", Ref: aCommit, AskedAt: asked,
+			State: link.AskInFlight, On: "ace", Started: started,
+			Request: link.BuildRequest{ID: "build-running", Check: &link.CheckRequest{Owner: "novox", Repo: "mesh-host"}}},
+		{Seq: 3, ID: "build-first", Repository: "ssh://forge/novox/mesh-catalog", Ref: "main", AskedAt: asked,
+			State: link.AskWaiting, Request: link.BuildRequest{ID: "build-first", Repository: "ssh://forge/novox/mesh-catalog"}},
+		{Seq: 4, ID: "build-second", Repository: "ssh://forge/novox/mesh-catalog", Path: "modules/gitea", Ref: aCommit,
+			AskedAt: now.Add(-time.Minute), State: link.AskWaiting,
+			Request: link.BuildRequest{ID: "build-second", Check: &link.CheckRequest{Owner: "novox", Repo: "mesh-catalog"}}},
+	}}
+}
+
+func TestTheQueueVerbAnswersEachAskAsData(t *testing.T) {
+	now := time.Date(2026, 10, 12, 12, 0, 0, 0, time.UTC)
+	q := aQueueOfEachKind(now)
+	got := queueAnswerOf(q, now)
+	if got.Waiting != 2 || got.InFlight != 1 || got.Dead != 1 || got.Seat != link.TheBuildMachine {
+		t.Fatalf("counts: %+v", got)
+	}
+	if got.Text != queueText(q, now) {
+		t.Fatalf("the data's text is not the table read from the same queue:\n%s", got.Text)
+	}
+	byID := map[string]queuedAnswer{}
+	for _, a := range got.Asks {
+		byID[a.ID] = a
+	}
+	running := byID["build-running"]
+	if running.Kind != "check" || running.Machine != "ace" || running.Commit != aCommit || running.Position != 0 ||
+		!running.Since.Equal(now.Add(-2*time.Minute)) || running.State != link.AskInFlight {
+		t.Errorf("in flight: %+v", running)
+	}
+	first, second := byID["build-first"], byID["build-second"]
+	if first.Position != 1 || first.Kind != "delivery" || first.Commit != "" || first.Ref != "main" || first.Machine != "" ||
+		!first.Since.Equal(now.Add(-5*time.Minute)) {
+		t.Errorf("first waiting: %+v", first)
+	}
+	if second.Position != 2 || second.Kind != "check" || second.Commit != aCommit || second.Path != "modules/gitea" ||
+		second.Repository != "ssh://forge/novox/mesh-catalog" {
+		t.Errorf("second waiting: %+v", second)
+	}
+	if dead := byID["build-dead"]; dead.Position != 0 || dead.State != link.AskDead {
+		t.Errorf("dead: %+v", dead)
+	}
+	// And the table says each ask's kind too (novox/hq issue 558).
+	for _, line := range []string{"build-running              check    ", "build-first                delivery ",
+		"build-second               check    ", "build-dead                 check    "} {
+		if !strings.Contains(got.Text, line) {
+			t.Errorf("the table does not say %q:\n%s", line, got.Text)
+		}
+	}
+	// In the table's order: in flight, then the waiting by position, then the dead.
+	var order []string
+	for _, a := range got.Asks {
+		order = append(order, a.ID)
+	}
+	if want := []string{"build-running", "build-first", "build-second", "build-dead"}; !reflect.DeepEqual(order, want) {
+		t.Errorf("order %v, want %v", order, want)
+	}
+}
+
+// The verb asks its command for JSON, and its answer carries the data while its output stays the table a
+// person reads, so a text caller reads what it always did.
+func TestTheQueueVerbKeepsTheTableAndCarriesTheData(t *testing.T) {
+	argv, err := argvFor("queue", nil)
+	if err != nil || !reflect.DeepEqual(argv, []string{"queue", "--json"}) {
+		t.Fatalf("queue's command line: %v %v", argv, err)
+	}
+	now := time.Now()
+	q := aQueueOfEachKind(now)
+	body, err := json.Marshal(queueAnswerOf(q, now))
+	if err != nil {
+		t.Fatal(err)
+	}
+	answer := answerOf(argv, body, "", true)
+	if answer.Output != queueText(q, now) {
+		t.Fatalf("the output is not the table:\n%s", answer.Output)
+	}
+	data, ok := answer.Answer.(map[string]any)
+	if !ok {
+		t.Fatalf("no data: %#v", answer.Answer)
+	}
+	if _, doubled := data["text"]; doubled {
+		t.Error("the table is said twice: once as the output and again inside the data")
+	}
+	asks, _ := data["asks"].([]any)
+	if len(asks) != 4 || data["waiting"] != float64(2) {
+		t.Fatalf("data: %v", data)
+	}
+	second := asks[2].(map[string]any)
+	if second["position"] != float64(2) || second["kind"] != "check" || second["commit"] != aCommit {
+		t.Errorf("second waiting: %v", second)
+	}
+	for _, a := range asks {
+		if _, held := a.(map[string]any)["held"]; held {
+			t.Error("an ask carries what the mesh holds")
+		}
+	}
+	// A failure is said as text, as before.
+	failed := answerOf(argv, nil, "mesh-controller: the bus cannot be reached\n", false)
+	if failed.Answer != nil || !strings.Contains(failed.Output, "cannot be reached") {
+		t.Errorf("a failure: %+v", failed)
+	}
+}
+
+// A repository named with a password never shows it, in the table or the data.
+func TestTheQueueNeverShowsARepositorysPassword(t *testing.T) {
+	if got := link.WithoutPassword("https://agent:s3cret@forge.example/novox/x.git"); strings.Contains(got, "s3cret") ||
+		!strings.Contains(got, "agent@forge.example/novox/x.git") {
+		t.Errorf("redacted: %s", got)
+	}
+	now := time.Now()
+	q := link.Queue{Seat: link.TheBuildMachine, Asks: []link.QueuedAsk{{Seq: 1, ID: "build-1",
+		Repository: "https://agent:s3cret@forge.example/novox/x.git", State: link.AskWaiting}}}
+	body, _ := json.Marshal(queueAnswerOf(q, now))
+	if strings.Contains(string(body), "s3cret") {
+		t.Errorf("the queue said a password: %s", body)
+	}
+	for _, kept := range []string{"ssh://git@forge:222/novox/x.git", "novox/x", "git@forge:novox/x.git", ""} {
+		if got := link.WithoutPassword(kept); got != kept {
+			t.Errorf("%q became %q", kept, got)
+		}
+	}
+}
+
+// A cancel says it deleted the ask only when it did: moved into order and gone since, it says so (novox/hq
+// issue 558).
+func TestACancelSaysDeletedOnlyWhenItDeleted(t *testing.T) {
+	ask := link.QueuedAsk{ID: "build-1", Repository: "novox/x", State: link.AskWaiting, Seq: 4}
+	if said := cancelSaid(ask, link.TheBuildMachine, 9); !strings.Contains(said, "deleted from the") {
+		t.Errorf("removed, it says: %s", said)
+	}
+	if said := cancelSaid(ask, link.TheBuildMachine, 0); strings.Contains(said, "deleted from") ||
+		!strings.Contains(said, "no longer in the") {
+		t.Errorf("gone already, it says: %s", said)
+	}
+}

cmd/mesh-controller/queue_test.go

@@ -326,7 +326,7 @@ func TestTheQueueVerbsRunTheirCommands(t *testing.T) {
 		args map[string]any
 		want []string
 	}{
-		{"queue", nil, []string{"queue"}},
+		{"queue", nil, []string{"queue", "--json"}},
 		{"cancel", map[string]any{"id": "build-1"}, []string{"cancel", "build-1"}},
 		{"clear", nil, []string{"clear"}},
 		{"clear", map[string]any{"dead": "true"}, []string{"clear", "--dead"}},

cmd/mesh-controller/reconnects_test.go

@@ -80,7 +80,7 @@ func TestAVerbsOwnProcessNamesItsConnection(t *testing.T) {
 	// A silence acts, so it is still its own process; it dials, and finds no such condition.
 	_, _ = handlers["conditions"](context.Background(),
 		json.RawMessage(`{"silence":"bus.nothing.here","for":"1h","why":"a test"}`))
-	names := closedNames(t, bus)
+	names := closedNames(t, bus, "mesh-controller verb conditions")
 	found := false
 	for _, n := range names {
 		found = found || n == "mesh-controller verb conditions"

cmd/mesh-controller/recorded_kept.go

@@ -135,6 +135,17 @@ func recordedKept(ctx context.Context, open *stores, node string) (map[string]st
 		}
 		out[m] = was
 	}
+	// **And the controller and the node-engine at the build the machine was last sent, over an older record**
+	// (novox/hq issue 201, core_downgrade.go). Under keepingEveryBuild they are kept already.
+	if !every {
+		core, err := coreKept(ctx, inv, node, sent, current)
+		if err != nil {
+			return nil, err
+		}
+		for m, was := range core {
+			out[m] = was
+		}
+	}
 	return out, nil
 }
 
@@ -159,6 +170,12 @@ func keepRecorded(ctx context.Context, open *stores, node string, shelf map[stri
 			return nil, fmt.Errorf("%s runs %s's build %s, which the build records no longer hold: the bus's user "+
 				"list cannot be sent there alone with it kept (novox/hq issue 490)", node, m, short(kept[m]))
 		}
+		if !found && guarded(coreComponent(m)) {
+			return nil, fmt.Errorf("%s was last sent %s's build %s, newer than the one the mesh holds, and the build records "+
+				"no longer hold it: this send cannot keep it and does not move it back — `push %s` sends the older build on "+
+				"a person's word, and a newer merge or `rebuild %s` moves the record forward (novox/hq issue 201)",
+				node, m, short(kept[m]), node, m)
+		}
 		if !found {
 			return nil, fmt.Errorf("%s records rather than rolls out, and %s runs its build %s, which the build "+
 				"records no longer hold: this send cannot keep it and does not move it — `push %s` sends the new "+

cmd/mesh-controller/release.go

@@ -51,6 +51,9 @@ type sendScope struct {
 	modules map[string]bool
 	// person is a person's act: it carries what it carries.
 	person bool
+	// puttingBack is a gate's own put-back of its modules: the one send that may carry a core module to a build
+	// older than the one its machine runs (novox/hq issue 201).
+	puttingBack bool
 }
 
 type sendScopeKey struct{}
@@ -237,6 +240,32 @@ var machineMoves = func(ctx context.Context, open *stores, f moveFacts, node str
 	return f.moves(node, modules, sent, known, all), nil
 }
 
+// withoutKept is a machine's moves less those its send keeps at the build the machine was last sent, and so does
+// not make: the grants step keeps every module (novox/hq issue 490), and every send keeps the controller and the
+// node-engine over an older record (issue 201). Read as the send composes it (sendKeeps, set after the checks that
+// call this), so a move it could not keep is still counted.
+func withoutKept(ctx context.Context, open *stores, node string, moves []inventory.CarriedMove) ([]inventory.CarriedMove, error) {
+	if len(moves) == 0 {
+		return moves, nil
+	}
+	keeping := ctx
+	if _, on := keptExcept(ctx); !on {
+		keeping = keepingRecorded(ctx)
+	}
+	keeps, err := recordedKept(keeping, open, node)
+	if err != nil || len(keeps) == 0 {
+		return moves, err
+	}
+	var out []inventory.CarriedMove
+	for _, mv := range moves {
+		if was, kept := keeps[mv.Module]; kept && sameCommit(was, mv.From) {
+			continue
+		}
+		out = append(out, mv)
+	}
+	return out, nil
+}
+
 // ungatedIn refuses a send whose machines would move a build no gate has seen, outside its scope: the
 // machines named, and why; the machine holding the bus, added only for its user list, is left instead.
 func ungatedIn(ctx context.Context, open *stores, names []string, addedHolder string) ([]string, error) {
@@ -254,19 +283,11 @@ func ungatedIn(ctx context.Context, open *stores, names []string, addedHolder st
 		if err != nil {
 			return nil, err
 		}
-		// The grants step composes every module at the build its machine was last sent (novox/hq issue 490):
-		// a move it keeps is not made. Read, not assumed, so a move it could not keep is still refused here.
-		var keeps map[string]string
-		if everyBuildKept(ctx, n) {
-			if keeps, err = recordedKept(ctx, open, n); err != nil {
-				return nil, err
-			}
+		if moves, err = withoutKept(ctx, open, n, moves); err != nil {
+			return nil, err
 		}
 		var waiting []string
 		for _, mv := range moves {
-			if was, kept := keeps[mv.Module]; kept && sameCommit(was, mv.From) {
-				continue
-			}
 			if !scope.judged[n] && !scope.modules[mv.Module] {
 				waiting = append(waiting, fmt.Sprintf("%s %s → %s", mv.Module, short(mv.From), short(mv.To)))
 			}
@@ -308,6 +329,11 @@ func gatedSend(ctx context.Context, open *stores, node string, owns []inventory.
 	if err != nil {
 		return nil, nil, nil, err
 	}
+	// A move the send keeps is not made, and is no move for the gate to judge (novox/hq issue 201): a core module
+	// kept over an older record judged as moving back to it would read the gate as superseded by its own send.
+	if moves, err = withoutKept(ctx, open, node, moves); err != nil {
+		return nil, nil, nil, err
+	}
 	own := func(module string) bool {
 		return slices.ContainsFunc(owns, func(o inventory.CarriedMove) bool { return o.Module == module })
 	}
@@ -812,14 +838,19 @@ func backlogCommand(ctx context.Context, sub string, args []string) error {
 	}
 	defer open.Close()
 	if sub == "release-backlog" {
-		release, err := open.inventory.HoldPlans(ctx, true)
-		if err != nil {
+		// Said on the bus (novox/hq ADR 0308 decision 1): the release plan starts walking here, and its start is
+		// said by the verb that opens it.
+		var p *inventory.Plan
+		if err := sayingOnTheBus(ctx, open.inventory, func() error {
+			release, err := open.inventory.HoldPlans(ctx, true)
+			if err != nil {
+				return err
+			}
+			defer release()
+			why.record(ctx, "upgrade release-backlog", nil)
+			p, err = releaseBacklog(ctx, open, link.Caller())
 			return err
-		}
-		defer release()
-		why.record(ctx, "upgrade release-backlog", nil)
-		p, err := releaseBacklog(ctx, open, link.Caller())
-		if err != nil {
+		}); err != nil {
 			return err
 		}
 		if p == nil {

cmd/mesh-controller/release_plan.go

@@ -1463,6 +1463,10 @@ func plansCommand(ctx context.Context, args []string) error {
 	modules := set.String("modules", "", "or the modules it would change, comma-separated")
 	moduleDirs := set.String("module-dirs", "", "with --paths: the directories holding a module.json at the commit, "+
 		"comma-separated, as the forge's announcer says them (novox/hq issue 278)")
+	// Following a plan (novox/hq issue 229): `plans wait <id>`.
+	until := set.String("until", "", "with wait: what to wait for — moved (any change), tier (its next tier) or done (its end)")
+	bound := set.String("bound", "", "with wait: how long to wait at most, as 15s or seconds (default and at most the "+
+		"longest a call is answered within)")
 	// Ending a plan by hand is a repair, and says why (novox/hq to-be 45 §7).
 	why := addHandActFlags(set)
 	positionals, err := parseAround(set, args)
@@ -1482,6 +1486,9 @@ func plansCommand(ctx context.Context, args []string) error {
 	defer open.Close()
 	inv := open.inventory
 	now := time.Now()
+	if len(positionals) == 2 && positionals[0] == "wait" {
+		return planWaitCommand(ctx, inv, positionals[1], *until, *bound)
+	}
 	if len(positionals) == 1 {
 		p, err := inv.PlanByID(ctx, positionals[0])
 		if err != nil {
@@ -1559,7 +1566,7 @@ func plansCommand(ctx context.Context, args []string) error {
 	if len(positionals) == 2 && positionals[0] == "go" {
 		why.record(ctx, "plans go", positionals[1:])
 		var p inventory.Plan
-		if err := sayingOnTheBus(ctx, func() (err error) {
+		if err := sayingOnTheBus(ctx, inv, func() (err error) {
 			p, err = letGo(ctx, inv, positionals[1], "a person ("+whoAsked()+")", strings.TrimSpace(*why.why))
 			return err
 		}); err != nil {
@@ -1571,8 +1578,13 @@ func plansCommand(ctx context.Context, args []string) error {
 	}
 	// `retry` (novox/hq ADR 0219): a failed plan's failed builds asked again, and the plan goes on.
 	if len(positionals) == 2 && positionals[0] == "retry" {
-		said, err := retryPlan(ctx, open, positionals[1])
-		if err != nil {
+		// Said on the bus (novox/hq ADR 0308 decision 1): a retried walk starts again, and its start is said
+		// by the verb that starts it.
+		var said string
+		if err := sayingOnTheBus(ctx, inv, func() (err error) {
+			said, err = retryPlan(ctx, open, positionals[1])
+			return err
+		}); err != nil {
 			return err
 		}
 		fmt.Println(said)
@@ -1586,26 +1598,29 @@ func plansCommand(ctx context.Context, args []string) error {
 		if positionals[0] == "close" {
 			how = "closed"
 		}
-		release, err := inv.HoldPlans(ctx, true)
-		if err != nil {
-			return err
-		}
-		defer release()
-		p, err := inv.PlanByID(ctx, positionals[1])
-		if err != nil {
-			return err
-		}
-		if !p.Open() {
-			return fmt.Errorf("%s is already %s", p.ID, p.State)
-		}
-		why.record(ctx, "plans "+positionals[0], positionals[1:])
-		p.State = inventory.PlanFailed
-		p.Note = how + " by hand at tier " + fmt.Sprint(p.Tier) + ": " + strings.TrimSpace(*why.why)
-		sayUnsent(&p, func(m string) bool {
-			u, err := inv.UpgradeOf(ctx, m)
-			return err == nil && u.RollOut
-		})
-		if err := inv.SavePlan(ctx, &p); err != nil {
+		// Said on the bus (novox/hq ADR 0308 decision 1): the walk's end, outcome stopped, is said by the verb
+		// that ends it, so what it touched is not held until its bound.
+		var p inventory.Plan
+		if err := sayingOnTheBus(ctx, inv, func() error {
+			release, err := inv.HoldPlans(ctx, true)
+			if err != nil {
+				return err
+			}
+			defer release()
+			if p, err = inv.PlanByID(ctx, positionals[1]); err != nil {
+				return err
+			}
+			if !p.Open() {
+				return fmt.Errorf("%s is already %s", p.ID, p.State)
+			}
+			why.record(ctx, "plans "+positionals[0], positionals[1:])
+			stopByHand(&p, how, "a person ("+whoAsked()+")", strings.TrimSpace(*why.why))
+			sayUnsent(&p, func(m string) bool {
+				u, err := inv.UpgradeOf(ctx, m)
+				return err == nil && u.RollOut
+			})
+			return inv.SavePlan(ctx, &p)
+		}); err != nil {
 			return err
 		}
 		fmt.Printf("%s %s at tier %d of %d; what was asked still builds and registers, nothing further is asked\n",
@@ -1924,3 +1939,15 @@ func forgetDeleted(ctx context.Context, inv *inventory.Inventory, module string,
 			"`module forget %s`: %v\n", p.ID, module, module, firstLine(err.Error()))
 	}
 }
+
+// stopByHand ends a walk a person stopped or closed (`plans stop|close`): failed, with who stopped it and why
+// kept as the delivery's owner keeps its own stop, so the walk ends with outcome stopped, not failed (novox/hq
+// ADR 0308 decision 1).
+func stopByHand(p *inventory.Plan, how, by, why string) {
+	p.State = inventory.PlanFailed
+	p.Note = how + " by hand at tier " + fmt.Sprint(p.Tier) + ": " + why
+	if p.Delivery == nil {
+		p.Delivery = &inventory.PlanDelivery{}
+	}
+	p.Delivery.Stopped, p.Delivery.StoppedWhy = by, why
+}

cmd/mesh-controller/replay201_test.go

@@ -0,0 +1,90 @@
+package main
+
+import (
+	"encoding/json"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// TestReplay201ThePlansSend replays novox/hq issue 201 (2026-10-02): two merges a minute apart made two plans; the
+// controller's plan rolled the newer controller onto the control node, and the node-engine's plan then sent that
+// machine the controller build before it, whose binary refused the seat row the newer one had widened. Here the
+// control node, anchor, was last sent the newer controller c2 while the mesh's record of the controller is the
+// build before it, c1, which passed its gate. The outcome asserted: a send that is no person's push — composed as a
+// plan's send composes it (keepingRecorded, what sendKeeps gives every send through sendToEach) — carries the
+// controller at c2, the build the machine was last sent, and not the older record; a person's push still carries
+// the record. Written with only what the controller had before its fix (mesh-controller #273) — the inventory's
+// build, gate, assignment and send records, keepingRecorded, planFor and declarationFor — so it is laid over the
+// commit before; the fix's own TestReplay201 reads what the fix added. Needs the store (MESH_TEST_POSTGRES), and
+// is named in testdata/store-tests.
+func TestReplay201ThePlansSend(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	inv := open.inventory
+	const older, newer = "c1aaaaaaaaaa", "c2bbbbbbbbbb"
+	old, now := time.Now().Add(-2*time.Hour), time.Now().Add(-time.Minute)
+	record := func(commit string, asked time.Time) inventory.Build {
+		t.Helper()
+		manifest, _ := json.Marshal(catalogue.Manifest{Module: "mesh-controller", Version: "1"})
+		b := inventory.Build{ID: "build-mesh-controller-" + commit, Module: "mesh-controller", Commit: commit,
+			Repository: "novox/mesh-controller", Manifest: manifest, Asked: asked, At: asked,
+			Made: []inventory.Artifact{{Name: "x", Kind: "bundle", Reference: "sha256:" + commit + "0000000000000000"}}}
+		if err := inv.RecordBuild(ctx, b); err != nil {
+			t.Fatal(err)
+		}
+		return b
+	}
+
+	// The older controller rolled out and passed its gate; the newer one was asked after it and registered.
+	before := record(older, old)
+	if err := inv.RecordGate(ctx, inventory.GateVerdict{Build: before.ID, Module: "mesh-controller", Commit: older,
+		Machines: []string{"anchor"}, Verdict: inventory.GatePassed}); err != nil {
+		t.Fatal(err)
+	}
+	record(newer, now)
+	if err := inv.RegisterModule(ctx, catalogue.Manifest{Module: "mesh-controller", Version: "1"}, inventory.Source{
+		Repository: "novox/mesh-controller", BuiltFrom: newer, Head: newer, Asked: now}); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := inv.Assign(ctx, "anchor", "mesh-controller"); err != nil {
+		t.Fatal(err)
+	}
+	// The controller's plan sent anchor the newer controller.
+	if err := inv.RecordSent(ctx, nodeID(t, open, "anchor"), "d-anchor", map[string]string{"mesh-controller": newer}); err != nil {
+		t.Fatal(err)
+	}
+	// And the mesh's record of the controller is the build before it — whatever made it so.
+	if err := inv.RestoreModule(ctx, before); err != nil {
+		t.Fatal(err)
+	}
+
+	// The controller each send to anchor carries: a plan's send keeps recorded builds (keepingRecorded, what
+	// sendKeeps gives every send but a person's push); a person's push composes the mesh's record.
+	controllerSent := func(sends string, keeping bool) string {
+		t.Helper()
+		c := ctx
+		if keeping {
+			c = keepingRecorded(ctx)
+		}
+		plan, settings, err := planFor(c, open, "anchor")
+		if err != nil {
+			t.Fatalf("%s to anchor did not compose: %v", sends, err)
+		}
+		declared, err := declarationFor(c, open, "anchor", plan, settings)
+		if err != nil {
+			t.Fatalf("%s to anchor did not compose: %v", sends, err)
+		}
+		return declared.Builds["mesh-controller"]
+	}
+
+	if got := controllerSent("a plan's send", true); got != newer {
+		t.Fatalf("a plan's send carried anchor the controller %s, older than the %s anchor was last sent: the "+
+			"older binary would read the row its successor widened", short(got), short(newer))
+	}
+	if got := controllerSent("a person's push", false); got != older {
+		t.Fatalf("a person's push carried the controller %s, not the mesh's record %s", short(got), short(older))
+	}
+}

cmd/mesh-controller/replay237_test.go

@@ -0,0 +1,85 @@
+package main
+
+import (
+	"bytes"
+	"io"
+	"os"
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+)
+
+// TestReplay237 replays novox/hq issue 237 (2026-10-04): a workstation already ran a module that
+// depends on a node seat nothing there held, and the module holding that seat was assigned to it. The
+// answer said the seat was now held, and then that the workstation was left out of the rest of the mesh
+// for lack of it, naming as the remedy the assignment just made. `plan` for the node, right after,
+// resolved. The outcome asserted: every line of the answer, as the controller seat's verb gives it
+// (standard output, then standard error), agrees with `plan` for the node right after the act. Written
+// with only what the controller had before its fix — register, assign's command, planFor — so it is laid
+// over the commit before.
+func TestReplay237(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	register(t, open, aContainer("web"))
+	register(t, open, catalogue.Manifest{Module: "docker", Version: "1",
+		Claims: []catalogue.Claim{{Name: catalogue.ContainerRuntimeSeat, Scope: catalogue.ScopeNode}}})
+	// Already on the node, from before the rule refused it: the node does not resolve until the
+	// holder comes.
+	if _, err := open.inventory.Assign(ctx, "laptop", "web"); err != nil {
+		t.Fatal(err)
+	}
+
+	said := answered(t, func() error { return assignCommand(ctx, "assign", []string{"laptop", "docker"}) })
+
+	if _, _, err := planFor(ctx, open, "laptop"); err != nil {
+		t.Fatalf("laptop does not resolve right after the act: %v\nthe answer was:\n%s", err, said)
+	}
+	if !strings.Contains(said, "web on laptop now has "+catalogue.ContainerRuntimeSeat+" held") {
+		t.Errorf("the answer does not say the seat is now held:\n%s", said)
+	}
+	for _, not := range []string{"laptop is left out", "does not resolve", "which nothing on laptop holds"} {
+		if strings.Contains(said, not) {
+			t.Errorf("the answer says %q, which `plan` right after contradicts:\n%s", not, said)
+		}
+	}
+}
+
+// answered is what a command says as the controller seat's verb answers it: standard output, then
+// standard error (answerOf).
+func answered(t *testing.T, f func() error) string {
+	t.Helper()
+	read := func(w **os.File) (func() string, error) {
+		old := *w
+		r, pw, err := os.Pipe()
+		if err != nil {
+			return nil, err
+		}
+		*w = pw
+		got := make(chan string)
+		go func() {
+			var buf bytes.Buffer
+			_, _ = io.Copy(&buf, r)
+			got <- buf.String()
+		}()
+		return func() string {
+			_ = pw.Close()
+			*w = old
+			return <-got
+		}, nil
+	}
+	stdout, err := read(&os.Stdout)
+	if err != nil {
+		t.Fatal(err)
+	}
+	stderr, err := read(&os.Stderr)
+	if err != nil {
+		t.Fatal(err)
+	}
+	runErr := f()
+	said := stdout() + stderr()
+	if runErr != nil {
+		t.Fatalf("%v\n%s", runErr, said)
+	}
+	return said
+}

cmd/mesh-controller/replay327_test.go

@@ -84,8 +84,12 @@ func asAProcess(t *testing.T, url string) {
 	t.Setenv(broker.CertificateVar, "")
 }
 
-// closedNames are the names of the connections the bus saw closed.
-func closedNames(t *testing.T, bus *server.Server) []string {
+// closedNames are the names of the connections the bus saw closed, waited for by want's own name: the
+// bus can register another connection's close first (the test's own setup connection, say), so returning
+// on the first non-empty list names whichever closed first, not necessarily the one being waited for
+// (novox/hq issue 543). closedNames instead waits until want itself appears among the closed connections,
+// or the deadline passes, and returns whatever names it last saw either way.
+func closedNames(t *testing.T, bus *server.Server, want string) []string {
 	t.Helper()
 	deadline := time.Now().Add(5 * time.Second)
 	var names []string
@@ -95,10 +99,14 @@ func closedNames(t *testing.T, bus *server.Server) []string {
 			t.Fatal(err)
 		}
 		names = names[:0]
+		found := false
 		for _, c := range connz.Conns {
 			names = append(names, c.Name)
+			if c.Name == want {
+				found = true
+			}
 		}
-		if len(names) > 0 {
+		if found {
 			return names
 		}
 		time.Sleep(50 * time.Millisecond)

cmd/mesh-controller/replay401_test.go

@@ -0,0 +1,83 @@
+package main
+
+import (
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+)
+
+// TestReplay401 replays novox/hq issue 401 (2026-10-10): the mounts module's smb-credentials, an own secret
+// only an outside party issues, was given by nobody, and the send made a random value for it and placed it on
+// the machine; the module read it as a credential given and wrong. The outcome asserted (ADR 0228): the send
+// makes no value for an own secret issued outside the mesh that nobody gave and places none, and a value the
+// mesh made for it before is not placed either; once a person gives one, that value is placed. Written with
+// only what the controller had before its fix (mesh-controller #262) — register, assign, planFor,
+// declarationFor and the inventory's secret reads — so it is laid over the commit before. Needs the store
+// (MESH_TEST_POSTGRES), and is named in testdata/store-tests.
+func TestReplay401(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	const made, outside = "/var/lib/mesh/mounts/password", "/var/lib/mesh/mounts/smb-credentials"
+	register(t, open, catalogue.Manifest{Module: "mounts", Version: "1",
+		OwnSecrets: catalogue.OwnSecrets{
+			"password":        {Path: made, Taken: catalogue.TakenAtStart},
+			"smb-credentials": {Path: outside, Taken: catalogue.TakenAtStart, IssuedBy: catalogue.IssuedOutside},
+		},
+		Resources: []map[string]any{
+			{"id": "state", "type": "directory", "path": "/var/lib/mesh/mounts", "mode": "0700"},
+		}})
+	if _, err := assign(ctx, open, "laptop", "mounts"); err != nil {
+		t.Fatal(err)
+	}
+	sent := func() []map[string]any {
+		t.Helper()
+		plan, settings, err := planFor(ctx, open, "laptop")
+		if err != nil {
+			t.Fatal(err)
+		}
+		declared, err := declarationFor(ctx, open, "laptop", plan, settings)
+		if err != nil {
+			t.Fatalf("the send to laptop did not compose: %v", err)
+		}
+		return declared.Resources
+	}
+	placed := func(resources []map[string]any, path string) map[string]any {
+		for _, r := range resources {
+			if r["path"] == path && r["sealed"] != nil {
+				return r
+			}
+		}
+		return nil
+	}
+
+	first := sent()
+	if placed(first, made) == nil {
+		t.Fatal("the secret the mesh makes was not placed")
+	}
+	if got := placed(first, outside); got != nil {
+		t.Errorf("the send placed a value for smb-credentials, which nobody gave: %v", got)
+	}
+	if _, held, err := open.inventory.ModuleSecretIfIssued(ctx, "laptop", "mounts", "smb-credentials"); err != nil || held {
+		t.Fatalf("the send made a value for a secret issued outside the mesh (held %v, %v)", held, err)
+	}
+
+	// A value the mesh made for it before the rule is not one a person gave: it is not placed.
+	if _, err := open.inventory.SecretForModule(ctx, "laptop", "mounts", "smb-credentials"); err != nil {
+		t.Fatal(err)
+	}
+	if got := placed(sent(), outside); got != nil {
+		t.Fatalf("a value the mesh made for a secret issued outside was placed: %v", got)
+	}
+
+	// Given by a person, it is placed, as given.
+	if err := open.inventory.AcceptSecretForModule(ctx, "laptop", "mounts", "smb-credentials", "the share's credentials"); err != nil {
+		t.Fatal(err)
+	}
+	given, held, err := open.inventory.ModuleSecretIfIssued(ctx, "laptop", "mounts", "smb-credentials")
+	if err != nil || !held {
+		t.Fatalf("the value given is not held (%v)", err)
+	}
+	if got := placed(sent(), outside); got == nil || got["sealed"] != given {
+		t.Fatalf("the value given is placed as %v", got)
+	}
+}

cmd/mesh-controller/seat_dependencies_test.go

@@ -15,7 +15,8 @@ import (
 func serviceManagerHolder() catalogue.Manifest {
 	return catalogue.Manifest{Module: "systemd", Version: "1",
 		Claims: []catalogue.Claim{{Name: catalogue.ServiceManagerSeat, Scope: catalogue.ScopeNode,
-			Serves: []string{"units", "status", "start", "stop", "restart", "enable", "disable", "journal"}}},
+			Serves: []string{"units", "status", "start", "stop", "restart", "enable", "disable", "journal",
+				"reset-failed", "wanted-by", "unlink-dangling"}}},
 		Resources: []map[string]any{{"id": "systemd", "type": "package", "package": "systemd"}}}
 }
 

cmd/mesh-controller/seats.go

@@ -34,8 +34,10 @@ type seatRow struct {
 	Delivers string `json:"delivers,omitempty"`
 	Decision string `json:"decision"`
 	// Replicated says the seat may be held on several machines at once (novox/hq ADR 0223).
-	Replicated bool         `json:"replicated,omitempty"`
-	Holders    []seatHolder `json:"holders"`
+	Replicated bool `json:"replicated,omitempty"`
+	// Paths are the paths on its machine the seat's holder owns (novox/hq ADR 0287).
+	Paths   []catalogue.SeatPath `json:"paths,omitempty"`
+	Holders []seatHolder         `json:"holders"`
 }
 
 // seatsHeld is every seat the mesh defines with its holders, and every claim held that names no
@@ -49,7 +51,7 @@ func seatsHeld(seats []catalogue.Seat, held []catalogue.Held) ([]seatRow, []cata
 	rows := make([]seatRow, 0, len(seats))
 	for _, s := range seats {
 		row := seatRow{Seat: s.Name, Scope: s.Scope, Delivers: s.Delivers, Decision: s.Decision,
-			Replicated: s.Replicated, Holders: []seatHolder{}}
+			Replicated: s.Replicated, Paths: s.Paths, Holders: []seatHolder{}}
 		seen := map[seatHolder]bool{}
 		for _, h := range held {
 			// Resolve the held claim to a seat rather than comparing names, so a record naming a
@@ -255,12 +257,16 @@ func seatsCommand(ctx context.Context, args []string) error {
 		return err
 	}
 	rows, outside := seatsHeld(catalogue.Seats(), world.Held)
+	// Which module owns each seat's path on each machine (novox/hq ADR 0287): the seat naming it, and
+	// that seat's holder there, with the stepping back applied.
+	owners := catalogue.PathOwners(catalogue.Seats(), world.Held)
 
 	if *asJSON {
 		out := struct {
-			Seats   []seatRow        `json:"seats"`
-			Outside []catalogue.Held `json:"outside,omitempty"`
-		}{rows, outside}
+			Seats   []seatRow             `json:"seats"`
+			Owners  []catalogue.PathOwner `json:"path-owners,omitempty"`
+			Outside []catalogue.Held      `json:"outside,omitempty"`
+		}{rows, owners, outside}
 		body, err := json.MarshalIndent(out, "", "  ")
 		if err != nil {
 			return err
@@ -270,7 +276,7 @@ func seatsCommand(ctx context.Context, args []string) error {
 	}
 
 	w := tabwriter.NewWriter(os.Stdout, 0, 0, 2, ' ', 0)
-	fmt.Fprintln(w, "SEAT\tSCOPE\tDELIVERS\tHELD BY")
+	fmt.Fprintln(w, "SEAT\tSCOPE\tDELIVERS\tPATHS\tHELD BY")
 	for _, r := range rows {
 		delivers := r.Delivers
 		if delivers == "" {
@@ -284,11 +290,22 @@ func seatsCommand(ctx context.Context, args []string) error {
 			}
 			holders = strings.Join(parts, ", ")
 		}
-		fmt.Fprintf(w, "%s\t%s\t%s\t%s\n", r.Seat, r.Scope, delivers, holders)
+		fmt.Fprintf(w, "%s\t%s\t%s\t%s\t%s\n", r.Seat, r.Scope, delivers, seatPathsText(r.Paths), holders)
 	}
 	if err := w.Flush(); err != nil {
 		return err
 	}
+	if len(owners) > 0 {
+		fmt.Println("\nwho owns each seat's path, by machine (novox/hq ADR 0287):")
+		w = tabwriter.NewWriter(os.Stdout, 0, 0, 2, ' ', 0)
+		fmt.Fprintln(w, "PATH\tMACHINE\tSEAT\tMODULE")
+		for _, o := range owners {
+			fmt.Fprintf(w, "%s\t%s\t%s\t%s\n", o.Path, o.Node, o.Seat, o.Module)
+		}
+		if err := w.Flush(); err != nil {
+			return err
+		}
+	}
 	if len(outside) > 0 {
 		fmt.Println("\nheld, and not a seat this mesh defines (registered before the set closed — novox/hq ADR 0110):")
 		for _, h := range outside {
@@ -297,3 +314,19 @@ func seatsCommand(ctx context.Context, args []string) error {
 	}
 	return nil
 }
+
+// seatPathsText is a seat's paths in one column: each path, and the seat it steps back for, if any.
+func seatPathsText(paths []catalogue.SeatPath) string {
+	if len(paths) == 0 {
+		return "—"
+	}
+	parts := make([]string, 0, len(paths))
+	for _, p := range paths {
+		if p.StepsBackFor != "" {
+			parts = append(parts, p.Path+" (steps back for "+p.StepsBackFor+")")
+			continue
+		}
+		parts = append(parts, p.Path)
+	}
+	return strings.Join(parts, ", ")
+}

cmd/mesh-controller/seats_test.go

@@ -74,3 +74,22 @@ func TestAKindedBenchIsNotHandedOver(t *testing.T) {
 		}
 	}
 }
+
+// The listing shows each seat's paths, and the seat a path steps back for (novox/hq ADR 0287).
+func TestTheSeatsListingShowsEachSeatsPaths(t *testing.T) {
+	rows, _ := seatsHeld(catalogue.Seats(), nil)
+	got := map[string]string{}
+	for _, r := range rows {
+		got[r.Seat] = seatPathsText(r.Paths)
+	}
+	for seat, want := range map[string]string{
+		"node-hostname":      "/etc/hosts, /etc/hostname",
+		"node-uplink":        "/etc/resolv.conf (steps back for node-resolver)",
+		"node-resolver":      "/etc/resolv.conf",
+		"node-packet-filter": "—",
+	} {
+		if got[seat] != want {
+			t.Errorf("%s lists its paths as %q, not %q", seat, got[seat], want)
+		}
+	}
+}

cmd/mesh-controller/seatverbs.go

@@ -314,6 +314,11 @@ func (a *verbArguments) commandLine() ([]string, error) {
 			return nil, err
 		}
 		return []string{"node", "show", str("node")}, nil
+	case "judge-directories":
+		if err := need("node"); err != nil {
+			return nil, err
+		}
+		return []string{"node", "judge-directories", str("node")}, nil
 	case "modules":
 		return []string{"module", "list", "--json"}, nil
 	case "seats":
@@ -331,6 +336,9 @@ func (a *verbArguments) commandLine() ([]string, error) {
 		}
 		return argv, nil
 	case "plans":
+		if err := plainPlanIDs(a.given); err != nil {
+			return nil, err
+		}
 		if r := str("repository"); r != "" {
 			argv := []string{"plans", "--what-if", r}
 			if p := str("paths"); p != "" {
@@ -360,6 +368,21 @@ func (a *verbArguments) commandLine() ([]string, error) {
 				return argv, nil
 			}
 		}
+		if id := str("wait"); id != "" {
+			// Following a plan (novox/hq issue 229): checked here too, so a call asking what no wait can do is
+			// refused before a command is started.
+			if _, _, err := planWaitAsked(a.given["until"], a.given["bound"]); err != nil {
+				return nil, err
+			}
+			argv := []string{"plans", "wait", id}
+			if u := str("until"); u != "" {
+				argv = append(argv, "--until", u)
+			}
+			if b := str("bound"); b != "" {
+				argv = append(argv, "--bound", b)
+			}
+			return argv, nil
+		}
 		if id := str("id"); id != "" {
 			return []string{"plans", id}, nil
 		}
@@ -426,7 +449,8 @@ func (a *verbArguments) commandLine() ([]string, error) {
 		return argv, nil
 	// The build queue (novox/hq ADR 0219).
 	case "queue":
-		return []string{"queue"}, nil
+		// As data, the table its output (novox/hq issue 455).
+		return []string{"queue", "--json"}, nil
 	case "cancel", "kill":
 		if err := need("id"); err != nil {
 			return nil, err
@@ -977,7 +1001,16 @@ var jsonVerbs = map[string]bool{"status": true, "seats": true, "plan": true, "co
 	// What the records say the registries may keep (novox/hq ADR 0251).
 	"artifacts": true, "collect": true, "images": true, "mirrors": true,
 	// The delivery's owner's verbs answer JSON where they read (plan, order, check, walks) — novox/hq ADR 0239.
-	"delivery": true}
+	"delivery": true,
+	// The build queue, each ask with its position among the waiting (novox/hq issue 455).
+	"queue": true,
+	// A plan followed (novox/hq issue 229): `plans wait` answers JSON; its other forms say text, and so answer no data.
+	"plans": true}
+
+// tableBesideVerbs are the JSON verbs whose document carries the table a person reads as its `text`: the
+// verb answers that table as its output, as it did before it answered data, and the rest as `answer` —
+// both from the one read, so they never disagree (novox/hq issue 455).
+var tableBesideVerbs = map[string]bool{"queue": true, "plans": true}
 
 // overviewVerbs are the JSON verbs whose answer is said once, as data, and not again as the text the
 // command printed: the overviews, which grow with the mesh (novox/hq issue 314). Every reader of theirs
@@ -1097,6 +1130,12 @@ func answerOf(argv []string, stdout []byte, stderr string, ok bool) verbAnswer {
 		var parsed any
 		if json.Unmarshal(bytes.TrimSpace(stdout), &parsed) == nil {
 			answer.Answer = parsed
+			if doc, isDoc := parsed.(map[string]any); isDoc && tableBesideVerbs[argv[0]] {
+				if table, said := doc["text"].(string); said {
+					answer.Output = table + stderr
+					delete(doc, "text")
+				}
+			}
 			if overviewVerbs[argv[0]] {
 				// Once, as data: the same document again as text doubled an answer that already
 				// outgrew one message of the bus (novox/hq issue 314).
@@ -1245,6 +1284,16 @@ func seatToolHandlers() (map[string]link.ToolHandler, []string, error) {
 				// Whatever it did, `status` is composed again once it has.
 				defer statusFrom.nudge()
 			}
+			if verb == "plans" && len(argv) > 1 && argv[1] == "wait" {
+				// A wait holds its answer up to its bound (novox/hq issue 229), and is answered in full inside it.
+				asked := ""
+				if i := slices.Index(argv, "--bound"); i > 0 && i+1 < len(argv) {
+					asked = argv[i+1]
+				}
+				if _, bound, err := planWaitAsked("", asked); err == nil {
+					link.AnswersWithin(ctx, bound+planWaitStart)
+				}
+			}
 			if answer, read := readHere(ctx, argv); read {
 				return answer, nil
 			}
@@ -1479,7 +1528,9 @@ func seatAnnouncement(handlers map[string]link.ToolHandler) micro.Info {
 }
 
 // nodeReads are the `node` subcommands a verb may run: the ones that only read.
-var nodeReads = map[string]bool{"list": true, "show": true}
+var nodeReads = map[string]bool{"list": true, "show": true,
+	// Read-only on the node too: the engine judges its directories and changes nothing (novox/hq issue 358).
+	"judge-directories": true}
 
 // flagsOnly says a command line's rest names no subcommand: empty, or beginning with a flag. For a command
 // with no subcommands every word is a flag, its value or a name it reads.

cmd/mesh-controller/seatverbs_schema_test.go

@@ -256,7 +256,7 @@ func stringLit(e ast.Expr) (string, bool) {
 var accountedFlags = map[string]map[string]string{
 	"status": {"json": "set by the verb: the answer is data"},
 	"seats":  {"json": "set by the verb: the answer is data"},
-	"queue":  {"json": "not set: the verb answers the table a person reads"},
+	"queue":  {"json": "set by the verb: the answer is data, its output the table (novox/hq issue 455)"},
 	"plan":   {"json": "set by the verb unless files is asked"},
 	"push": {
 		"wait": "set by the verb to 0: a tool call cannot hold a connection for a whole apply",

cmd/mesh-controller/signals.go

@@ -254,6 +254,16 @@ var signalsTable = []signalRow{
 		newest: func(f *signalFacts) time.Time {
 			return newestOf(f.bus.waits, func(w busWaitFacts) time.Time { return w.since })
 		}},
+	{Row: "S21", Signal: "a clean apply", Emitter: "node-engine", Trigger: "each report of a declaration refused or applied only in part (novox/hq issue 233)",
+		Bound: "one apply interval (5 min) past the first report of the same failure, judged by time while the machine " +
+			"is heard — the node-engine says a re-apply only when how it went changed; not while it is silent or " +
+			"asleep; naming the refusal, or the package manager that does not answer with its words; cleared by the " +
+			"clean apply it then says",
+		Kind: kindApplyFailing, Severity: conditions.Warning, Phase: 2,
+		needs: func(f *signalFacts) error { return f.doingErr }, watch: watchApplyFailing,
+		newest: func(f *signalFacts) time.Time {
+			return newestOf(f.doing, func(d inventory.Doing) time.Time { return d.At })
+		}},
 }
 
 // watchFacts is S14: the snapshot a merge check is fed is older than its bound, or none was kept since

cmd/mesh-controller/signals_test.go

@@ -186,6 +186,14 @@ var suppressions = map[string]suppression{
 		},
 		past: func(f *signalFacts) { f.refusedSends = []inventory.Send{refusedSend(f.now.Add(-time.Second))} },
 	},
+	// A machine whose package manager does not answer (novox/hq issue 233): said once its first report of the
+	// failure is older than one apply interval while it is heard. Inside: exactly five minutes old.
+	"S21": {
+		inside: func(f *signalFacts) { f.doing = []inventory.Doing{unansweringPackageManager(f.now, 5*time.Minute, 1)} },
+		past: func(f *signalFacts) {
+			f.doing = []inventory.Doing{unansweringPackageManager(f.now, 5*time.Minute+time.Second, 1)}
+		},
+	},
 	// Twice by hand within a fortnight is a healer wanted; once, or the first of two a day too old, is not.
 	"S15": {
 		inside: func(f *signalFacts) {

cmd/mesh-controller/status_summary.go

@@ -172,7 +172,7 @@ func composeStatus(open *stores) func(context.Context) ([]byte, error) {
 var readingVerbs = map[string]bool{
 	"tools": true, "calls": true, "status": true, "nodes": true, "node": true, "modules": true,
 	"seats": true, "builds": true, "plan": true, "queue": true, "durations": true, "hand-acts": true,
-	"doctor": true, "conditions": true, "healers": true,
+	"doctor": true, "conditions": true, "healers": true, "judge-directories": true,
 }
 
 // nudgingListener is the enrolment, nudging the summary when a machine said something new.

cmd/mesh-controller/terminal_settings_test.go

@@ -344,3 +344,58 @@ func TestAnyKeyOfAModuleWithATrustedMergeableFileIsRefusedThroughAVerb(t *testin
 		t.Fatalf("a file marked untrusted through the verb: %v", err)
 	}
 }
+
+// Who owns a module's directory is said at the terminal alone (novox/hq issue 279): a directory's owner may name
+// the settings the module runs as, root chowns the folder to them at the next push, and through the settings verb
+// any caller could have set puid to 0 or to its own uid. The key is refused through every verb route even where a
+// file nothing trusts also asks for it, and taken at the terminal; the layer a refused call meets is unchanged.
+func TestADirectoryOwnersKeyIsRefusedThroughAVerb(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	register(t, open, catalogue.Manifest{Module: "sonarr", Version: "1",
+		Resources: []map[string]any{
+			{"id": "recycle-bin", "type": "directory", "mode": "0755", "owner": "${setting:puid}:${setting:pgid}"},
+			{"id": "identity", "type": "file", "path": "/etc/sonarr.env", "mode": "0644", "trusted": false,
+				"content": "PUID=${setting:puid}\nPGID=${setting:pgid}\nX=${setting:x}\n"}}})
+	if err := atTheTerminal(t, "settings", "set", "sonarr", `{"puid":1001,"pgid":2000,"x":0}`,
+		"--node", "anchor"); err != nil {
+		t.Fatalf("the owner at the terminal: %v", err)
+	}
+	if _, err := assign(ctx, open, "anchor", "sonarr"); err != nil {
+		t.Fatal(err)
+	}
+	layer := func() string {
+		t.Helper()
+		values, _, err := open.inventory.Layer(ctx, "anchor", "sonarr")
+		if err != nil {
+			t.Fatal(err)
+		}
+		raw, _ := json.Marshal(values)
+		return string(raw)
+	}
+	kept := layer()
+	refused := func(what string, err error) {
+		t.Helper()
+		if err == nil || !strings.Contains(err.Error(), "controller's terminal") {
+			t.Fatalf("%s: %v", what, err)
+		}
+	}
+	refused("puid 0 through the verb", throughVerb(t, "settings", map[string]any{"module": "sonarr",
+		"node": "anchor", "values": `{"puid":0,"pgid":2000,"x":0}`}))
+	refused("pgid through the verb, mesh-wide", throughVerb(t, "settings", map[string]any{"module": "sonarr",
+		"values": `{"pgid":0}`}))
+	refused("cleared through the verb", throughVerb(t, "settings", map[string]any{"module": "sonarr",
+		"node": "anchor", "clear": "true"}))
+	if err := throughVerb(t, "command", map[string]any{
+		"command": `settings set sonarr '{"puid":0,"pgid":2000,"x":0}' --node anchor`}); err == nil {
+		t.Fatal("the command verb set the owner")
+	}
+	if got := layer(); got != kept {
+		t.Fatalf("a refused call changed the layer: %s, was %s", got, kept)
+	}
+	// Another key, the owner kept, is still the verb's.
+	if err := throughVerb(t, "settings", map[string]any{"module": "sonarr", "node": "anchor",
+		"values": `{"puid":1001,"pgid":2000,"x":1}`}); err != nil {
+		t.Fatalf("another key through the verb, the owner kept: %v", err)
+	}
+}

cmd/mesh-controller/unbound.go

@@ -0,0 +1,21 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+)
+
+// unboundLines say which optional requirements of a machine's modules nothing assigned answers
+// (novox/hq ADR 0330 §7): left unbound rather than refused, with nothing installed for them, so the
+// module runs without — and said, because a data source that never appears is otherwise a silence.
+// Each binds without anybody's act on the first composition after a provider is assigned.
+func unboundLines(plan catalogue.Resolution) []string {
+	lines := make([]string, 0, len(plan.Absent))
+	for _, a := range plan.Absent {
+		lines = append(lines, fmt.Sprintf(
+			"  unbound  %s, optional for %s — nothing assigned provides it; it binds once a provider is "+
+				"assigned (novox/hq ADR 0330)", a.Requirement, a.Consumer))
+	}
+	return lines
+}

cmd/mesh-controller/unbound_test.go

@@ -0,0 +1,59 @@
+package main
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+)
+
+// A machine running grafana without influxdb says so (novox/hq ADR 0330 §7, issue 166): `plan` and
+// `node` list the optional requirement nothing assigned answers, and the requirement is left
+// absent rather than refused — influxdb is in the catalogue and is not installed for it.
+func TestPlanAndNodeListAnOptionalRequirementLeftUnbound(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	register(t, open, catalogue.Manifest{Module: "influxdb", Version: "1",
+		Provides: catalogue.FromAnywhere("influxdb-api")})
+	register(t, open, catalogue.Manifest{Module: "grafana", Version: "1",
+		Requires: []string{"influxdb-api"}, OptionalRequires: map[string]bool{"influxdb-api": true},
+		Resources: []map[string]any{{"id": "state", "type": "directory", "path": "/var/lib/grafana", "mode": "0700"}}})
+	if _, err := assign(ctx, open, "laptop", "grafana"); err != nil {
+		t.Fatalf("grafana could not be assigned on a mesh without influxdb: %v", err)
+	}
+
+	plan, _, err := planFor(ctx, open, "laptop")
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, m := range plan.Modules {
+		if m.Module == "influxdb" {
+			t.Fatal("influxdb was installed for grafana's optional requirement (ADR 0330 §3)")
+		}
+	}
+	const said = "unbound  influxdb-api, optional for grafana"
+	if shown := printed(t, func() error { return planCommand(ctx, []string{"laptop"}) }); !strings.Contains(shown, said) {
+		t.Errorf("plan laptop does not say influxdb-api is unbound:\n%s", shown)
+	}
+	if shown := printed(t, func() error { return showNode(ctx, open, "laptop") }); !strings.Contains(shown, said) {
+		t.Errorf("node show laptop does not say influxdb-api is unbound:\n%s", shown)
+	}
+	// And once influxdb is assigned somewhere, grafana binds to it with no act on grafana.
+	if _, err := assign(ctx, open, "anchor", "influxdb"); err != nil {
+		t.Fatal(err)
+	}
+	plan, _, err = planFor(ctx, open, "laptop")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(plan.Absent) != 0 {
+		t.Fatalf("still absent after influxdb was assigned: %+v", plan.Absent)
+	}
+	var bound bool
+	for _, n := range plan.Needs {
+		bound = bound || n.For == "grafana" && n.Name == "influxdb-api" && n.From == "anchor"
+	}
+	if !bound {
+		t.Fatalf("grafana was not bound to influxdb on anchor: %+v", plan.Needs)
+	}
+}

cmd/mesh-controller/walk_said.go

@@ -0,0 +1,334 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"slices"
+	"sort"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/broker"
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// What a walk touches, its bound and its outcome (novox/hq ADR 0308 decision 1, decision 5): said in
+// `plan-moved` on the save that starts the walk and the save that ends it, beside the walk whole, for the holder
+// of the operator's channel to hold what the walk touches while it runs and tell its result once.
+//
+// **What a walk touches** is every module it moves on every machine it sends it to, and every module a moved
+// tool runner (node-tools) or node-engine (mesh-host) carries on that machine: what restarts there. At the start
+// that is what the walk will send — each module of its tiers whose policy rolls it out, on every machine running
+// it; at the end it is what it reached — the machines each module was sent to, first and rest, and what a gated
+// send carried with it.
+//
+// **Its bound** is twice the largest delivery budget among the walk's deliveries (deliveryBudgets: a core
+// module's ten minutes, a leaf module's budget in force), and fifteen minutes, not doubled, for a walk none of
+// whose deliveries has a budget: a release plan (builds waiting for a person's gate), a walk whose every module's
+// policy records rather than rolls out (held for a person, ADR 0282 decision 1), or a walk kept without a class.
+
+// walkNoBudgetBound is the bound of a walk with no budget (ADR 0308 decision 5): not doubled.
+const walkNoBudgetBound = 15 * time.Minute
+
+// budgetNone is the budget class of a walk none of whose deliveries has a budget.
+const budgetNone = "none"
+
+// walkSaid is what `plan-moved` adds on a walk's start and end, beside the walk whole.
+type walkSaid struct {
+	Walk  string `json:"walk"`
+	Phase string `json:"phase"`
+	// Touches is, per machine, the modules the walk moves or reaches there and what a moved tool runner or
+	// node-engine carries there; never null.
+	Touches []walkTouch `json:"touches"`
+	// Outcome is on the end only: delivered, failed or stopped.
+	Outcome string `json:"outcome,omitempty"`
+	// BoundSeconds and BudgetClass are said on both, read from the walk's class at the start.
+	BoundSeconds int    `json:"bound_seconds"`
+	BudgetClass  string `json:"budget_class"`
+	// StartedAt is when the walk was said started, on both; EndedAt when it was said ended, on the end: the
+	// bound runs from StartedAt, whenever the event is heard.
+	StartedAt *time.Time `json:"started_at,omitempty"`
+	EndedAt   *time.Time `json:"ended_at,omitempty"`
+}
+
+// walkTouch is what a walk touches on one machine.
+type walkTouch struct {
+	Machine string   `json:"machine"`
+	Modules []string `json:"modules"`
+	// Carried names those of Modules that are there only because a moved tool runner or node-engine carries
+	// them: what restarts with it, not what the walk builds.
+	Carried []string `json:"carried,omitempty"`
+}
+
+// planMovedBody is `plan-moved`'s body: the walk whole, as before, and on its start and end what it touches.
+type planMovedBody struct {
+	inventory.Plan
+	*walkSaid
+}
+
+// walkFacts is what the touches are read from: the controller's inventory.
+type walkFacts interface {
+	Running(ctx context.Context, module string) ([]string, error)
+	UpgradeOf(ctx context.Context, module string) (inventory.Upgrade, error)
+	Assigned(ctx context.Context, node string) ([]string, error)
+	SentBuilds(ctx context.Context, node string) (map[string]string, bool, error)
+	Catalogue(ctx context.Context) (map[string]catalogue.Manifest, error)
+}
+
+// sayWalk is what `plan-moved` adds to the save that started or ended the walk; nil on every other save. A fact
+// that cannot be read is said on the controller's log and left out, never in the way of the event: a walk said
+// with fewer touches is held less, never longer.
+func sayWalk(ctx context.Context, facts walkFacts, p inventory.Plan) *walkSaid {
+	if p.WalkSaid == "" {
+		return nil
+	}
+	w := &walkSaid{Walk: p.ID, Phase: p.WalkSaid}
+	if p.Times != nil {
+		w.StartedAt = p.Times.Started
+		if p.WalkSaid == inventory.WalkEnded {
+			w.EndedAt, w.Outcome = p.Times.Ended, p.Outcome()
+		}
+	}
+	read := readWalkFacts(ctx, facts, p)
+	w.BudgetClass = walkBudgetClass(p, read.rollsOut)
+	w.BoundSeconds = int(walkBound(w.BudgetClass) / time.Second)
+	var moved map[string][]string
+	if p.WalkSaid == inventory.WalkStarted {
+		moved = walkSends(p, read.running, read.rollsOut)
+	} else {
+		moved = walkReached(p, read.running)
+	}
+	var shelf map[string]catalogue.Manifest
+	if len(moved[broker.RuntimeModule]) > 0 {
+		// Which modules the tool runner serves is the catalogue's: read only when the walk moves it.
+		shelf = read.shelf()
+	}
+	w.Touches = touchesOf(moved, read.onMachine(moved), shelf)
+	return w
+}
+
+// walkBudgetClass is the largest budget class among the walk's deliveries: its class read at the cut when one of
+// its modules rolls out, and none when it has no budget.
+func walkBudgetClass(p inventory.Plan, rollsOut func(string) bool) string {
+	if p.Release != nil || p.Times == nil {
+		return budgetNone
+	}
+	if _, budgeted := deliveryBudgets[p.Times.Class]; !budgeted {
+		return budgetNone
+	}
+	for _, tier := range p.Tiers {
+		for _, m := range tier {
+			if rollsOut(m) {
+				return p.Times.Class
+			}
+		}
+	}
+	return budgetNone
+}
+
+// walkBound is a walk's bound by its budget class: twice its budget, or fifteen minutes with none.
+func walkBound(class string) time.Duration {
+	if b, ok := deliveryBudgets[class]; ok {
+		return 2 * b
+	}
+	return walkNoBudgetBound
+}
+
+// walkSends is what a walk will send at its start, per module the machines it goes to: each module of its tiers
+// whose policy rolls it out, on every machine running it (for a release plan, those of its order).
+func walkSends(p inventory.Plan, running func(string) []string, rollsOut func(string) bool) map[string][]string {
+	out := map[string][]string{}
+	for _, tier := range p.Tiers {
+		for _, m := range tier {
+			if s := p.Modules[m]; s != nil && s.State == planDeleted {
+				continue
+			}
+			if p.Release == nil && !rollsOut(m) {
+				continue
+			}
+			for _, n := range running(m) {
+				if p.Release != nil && !slices.Contains(p.Release.Order, n) {
+					continue
+				}
+				out[m] = appendNew(out[m], n)
+			}
+		}
+	}
+	return out
+}
+
+// walkReached is what a walk sent by its end, per module the machines it reached: its first machines, its rest,
+// and every module a gated send carried with it. A release plan reached the machines it walked: those done and
+// the one being judged.
+func walkReached(p inventory.Plan, running func(string) []string) map[string][]string {
+	out := map[string][]string{}
+	carried := func(g *inventory.PlanGate) {
+		if g == nil {
+			return
+		}
+		for _, c := range g.Carried {
+			out[c.Module] = appendNew(out[c.Module], c.Node)
+		}
+	}
+	if r := p.Release; r != nil {
+		reached := append([]string{}, r.Done...)
+		if r.Gate != nil {
+			reached = appendNew(reached, r.Gate.Machines...)
+			carried(r.Gate)
+		}
+		for _, tier := range p.Tiers {
+			for _, m := range tier {
+				for _, n := range running(m) {
+					if slices.Contains(reached, n) {
+						out[m] = appendNew(out[m], n)
+					}
+				}
+			}
+		}
+		return out
+	}
+	for m, s := range p.Modules {
+		if s == nil {
+			continue
+		}
+		out[m] = appendNew(out[m], s.First...)
+		for n := range s.Rest {
+			out[m] = appendNew(out[m], n)
+		}
+		carried(s.Gate)
+		if len(out[m]) == 0 {
+			delete(out, m)
+		}
+	}
+	return out
+}
+
+// touchesOf turns what a walk moves, per module, into what it touches, per machine: the modules it moves there,
+// and, where it moves the tool runner, every module there whose tools it serves, and where it moves the
+// node-engine, every module there. Sorted by machine and module.
+func touchesOf(moved map[string][]string, on map[string][]string, shelf map[string]catalogue.Manifest) []walkTouch {
+	byMachine := map[string][]string{}
+	for m, machines := range moved {
+		for _, n := range machines {
+			byMachine[n] = appendNew(byMachine[n], m)
+		}
+	}
+	out := make([]walkTouch, 0, len(byMachine))
+	for n, modules := range byMachine {
+		t := walkTouch{Machine: n, Modules: modules}
+		engine, runner := slices.Contains(modules, hostModule), slices.Contains(modules, broker.RuntimeModule)
+		if engine || runner {
+			for _, m := range on[n] {
+				if slices.Contains(t.Modules, m) || (!engine && !servesTools(shelf[m])) {
+					continue
+				}
+				t.Modules = append(t.Modules, m)
+				t.Carried = append(t.Carried, m)
+			}
+		}
+		sort.Strings(t.Modules)
+		sort.Strings(t.Carried)
+		out = append(out, t)
+	}
+	sort.Slice(out, func(i, j int) bool { return out[i].Machine < out[j].Machine })
+	return out
+}
+
+// servesTools says the tool runner serves something of this module: a bundle it loads entrypoints from, or the
+// module's own tools.
+func servesTools(m catalogue.Manifest) bool {
+	if len(m.Tools) > 0 {
+		return true
+	}
+	for _, b := range m.Bundles {
+		if len(b.Loads) > 0 {
+			return true
+		}
+	}
+	return false
+}
+
+// walkRead is the facts a walk's touches are worked out from, read once per event.
+type walkRead struct {
+	running   func(string) []string
+	rollsOut  func(string) bool
+	onMachine func(moved map[string][]string) map[string][]string
+	shelf     func() map[string]catalogue.Manifest
+}
+
+// readWalkFacts reads what the walk's touches need. Without facts (a test, a command with no store), nothing runs
+// anywhere and every module rolls out: the touches are then what the walk itself recorded.
+func readWalkFacts(ctx context.Context, facts walkFacts, p inventory.Plan) walkRead {
+	cantRead := func(what string, err error) {
+		fmt.Fprintf(os.Stderr, "%s: %s cannot be read for what the walk touches: %v\n", p.ID, what, err)
+	}
+	r := walkRead{
+		running:   func(string) []string { return nil },
+		rollsOut:  func(string) bool { return true },
+		onMachine: func(map[string][]string) map[string][]string { return nil },
+		shelf:     func() map[string]catalogue.Manifest { return nil },
+	}
+	if facts == nil {
+		return r
+	}
+	running := map[string][]string{}
+	r.running = func(m string) []string {
+		if on, read := running[m]; read {
+			return on
+		}
+		on, err := facts.Running(ctx, m)
+		if err != nil {
+			cantRead("where "+m+" runs", err)
+		}
+		running[m] = on
+		return on
+	}
+	rolls := map[string]bool{}
+	r.rollsOut = func(m string) bool {
+		if yes, read := rolls[m]; read {
+			return yes
+		}
+		u, err := facts.UpgradeOf(ctx, m)
+		if err != nil {
+			cantRead(m+"'s policy", err)
+		}
+		// A policy that cannot be read is taken to roll out: the walk is then held more, never less.
+		rolls[m] = err != nil || u.RollOut
+		return rolls[m]
+	}
+	r.onMachine = func(moved map[string][]string) map[string][]string {
+		out := map[string][]string{}
+		for _, core := range []string{hostModule, broker.RuntimeModule} {
+			for _, n := range moved[core] {
+				if _, read := out[n]; read {
+					continue
+				}
+				var there []string
+				if sent, known, err := facts.SentBuilds(ctx, n); err != nil {
+					cantRead("what "+n+" was sent", err)
+				} else if known {
+					for m := range sent {
+						there = append(there, m)
+					}
+				}
+				if assigned, err := facts.Assigned(ctx, n); err != nil {
+					cantRead("what "+n+" is assigned", err)
+				} else {
+					there = appendNew(there, assigned...)
+				}
+				sort.Strings(there)
+				out[n] = there
+			}
+		}
+		return out
+	}
+	r.shelf = func() map[string]catalogue.Manifest {
+		shelf, err := facts.Catalogue(ctx)
+		if err != nil {
+			cantRead("the catalogue", err)
+		}
+		return shelf
+	}
+	return r
+}

cmd/mesh-controller/walk_said_test.go

@@ -0,0 +1,514 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"os"
+	"reflect"
+	"testing"
+	"time"
+
+	"github.com/nats-io/nats.go"
+
+	"github.com/novox/mesh-controller/internal/broker"
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+	"github.com/novox/mesh-controller/internal/testbus"
+)
+
+// fakeWalkFacts is the inventory as far as a walk's touches read it.
+type fakeWalkFacts struct {
+	running  map[string][]string
+	records  map[string]bool // modules whose policy records rather than rolls out
+	sent     map[string]map[string]string
+	assigned map[string][]string
+	shelf    map[string]catalogue.Manifest
+}
+
+func (f fakeWalkFacts) Running(_ context.Context, m string) ([]string, error) {
+	return f.running[m], nil
+}
+func (f fakeWalkFacts) UpgradeOf(_ context.Context, m string) (inventory.Upgrade, error) {
+	return inventory.Upgrade{RollOut: !f.records[m]}, nil
+}
+func (f fakeWalkFacts) Assigned(_ context.Context, n string) ([]string, error) {
+	return f.assigned[n], nil
+}
+func (f fakeWalkFacts) SentBuilds(_ context.Context, n string) (map[string]string, bool, error) {
+	s, ok := f.sent[n]
+	return s, ok, nil
+}
+func (f fakeWalkFacts) Catalogue(context.Context) (map[string]catalogue.Manifest, error) {
+	return f.shelf, nil
+}
+
+// theMesh is four machines: the tool runner on each, messenger and mesh-issues on novox, gitea on ace.
+func theMesh() fakeWalkFacts {
+	return fakeWalkFacts{
+		running: map[string][]string{
+			broker.RuntimeModule: {"ace", "g14", "novox", "shanks"},
+			"messenger":          {"novox"},
+			"gitea":              {"ace"},
+			"plex":               {"ace"},
+		},
+		sent: map[string]map[string]string{
+			"novox": {broker.RuntimeModule: "c0", "messenger": "c1", "mesh-issues": "c2", "postgres": "c3"},
+			"ace":   {broker.RuntimeModule: "c0", "gitea": "c4"},
+		},
+		assigned: map[string][]string{"g14": {broker.RuntimeModule, "desktop"}, "shanks": {broker.RuntimeModule}},
+		shelf: map[string]catalogue.Manifest{
+			"messenger":   {Module: "messenger", Tools: []string{"notify"}},
+			"mesh-issues": {Module: "mesh-issues", Bundles: []catalogue.Bundle{{Name: "tools", Loads: []string{"main"}}}},
+			"postgres":    {Module: "postgres"},
+			"gitea":       {Module: "gitea", Tools: []string{"gitea_api"}},
+			"desktop":     {Module: "desktop", Tools: []string{"notify_send"}},
+		},
+	}
+}
+
+func walkOfTiers(class string, tiers ...[]string) inventory.Plan {
+	cut := time.Date(2026, 10, 12, 11, 0, 0, 0, time.UTC)
+	started := cut.Add(time.Second)
+	p := inventory.Plan{ID: "plan-308", State: inventory.PlanBuilding, Tiers: tiers,
+		Modules: map[string]*inventory.PlanModule{}, Times: &inventory.PlanTimes{Cut: &cut, Class: class, Started: &started}}
+	for _, tier := range tiers {
+		for _, m := range tier {
+			p.Modules[m] = &inventory.PlanModule{}
+		}
+	}
+	p.WalkSaid = inventory.WalkStarted
+	return p
+}
+
+// novox/hq ADR 0308 How it is checked §1: the start names the modules the walk moves and the machines it sends
+// them to, and every module a moved tool runner carries there.
+func TestAWalksStartNamesWhatItTouchesWithWhatTheToolRunnerCarries(t *testing.T) {
+	p := walkOfTiers(inventory.ClassCore, []string{broker.RuntimeModule}, []string{"messenger"})
+	w := sayWalk(t.Context(), theMesh(), p)
+	if w == nil || w.Walk != "plan-308" || w.Phase != inventory.WalkStarted || w.Outcome != "" {
+		t.Fatalf("the start is said: %+v", w)
+	}
+	want := []walkTouch{
+		{Machine: "ace", Modules: []string{"gitea", broker.RuntimeModule}, Carried: []string{"gitea"}},
+		{Machine: "g14", Modules: []string{"desktop", broker.RuntimeModule}, Carried: []string{"desktop"}},
+		// postgres serves no tools: the tool runner does not carry it.
+		{Machine: "novox", Modules: []string{"mesh-issues", "messenger", broker.RuntimeModule}, Carried: []string{"mesh-issues"}},
+		{Machine: "shanks", Modules: []string{broker.RuntimeModule}},
+	}
+	if !reflect.DeepEqual(w.Touches, want) {
+		t.Fatalf("touches:\n got %+v\nwant %+v", w.Touches, want)
+	}
+	if w.BudgetClass != inventory.ClassCore || w.BoundSeconds != 1200 || w.StartedAt == nil {
+		t.Fatalf("a core walk is bound at 20 minutes: %+v", w)
+	}
+}
+
+// A moved node-engine carries every module on its machine; a module whose policy records is not sent, and not
+// touched.
+func TestAMovedNodeEngineCarriesEverythingOnItsMachine(t *testing.T) {
+	f := theMesh()
+	f.running[hostModule] = []string{"novox"}
+	f.records = map[string]bool{"plex": true}
+	p := walkOfTiers(inventory.ClassCore, []string{hostModule, "plex"})
+	w := sayWalk(t.Context(), f, p)
+	want := []walkTouch{{Machine: "novox",
+		Modules: []string{"mesh-host", "mesh-issues", "messenger", "node-tools", "postgres"},
+		Carried: []string{"mesh-issues", "messenger", "node-tools", "postgres"}}}
+	if !reflect.DeepEqual(w.Touches, want) {
+		t.Fatalf("touches:\n got %+v\nwant %+v", w.Touches, want)
+	}
+}
+
+// The end names what the walk reached — its first machines, its rest, what a gated send carried — and its
+// outcome; the modules a reached tool runner carries are touched there too.
+func TestAWalksEndNamesWhatItReachedAndItsOutcome(t *testing.T) {
+	p := walkOfTiers(inventory.ClassCore, []string{broker.RuntimeModule}, []string{"messenger"})
+	ended := p.Times.Started.Add(4 * time.Minute)
+	p.Times.Ended = &ended
+	p.State, p.WalkSaid = inventory.PlanDone, inventory.WalkEnded
+	p.Modules[broker.RuntimeModule] = &inventory.PlanModule{First: []string{"shanks"},
+		Rest: map[string]inventory.SentDeclaration{"novox": {}},
+		Gate: &inventory.PlanGate{Carried: []inventory.CarriedMove{{Module: "gitea", Node: "shanks"}}}}
+	// messenger was built and found unchanged: no move, not reached.
+	p.Modules["messenger"] = &inventory.PlanModule{Why: "no move"}
+	w := sayWalk(t.Context(), theMesh(), p)
+	if w.Phase != inventory.WalkEnded || w.Outcome != inventory.WalkDelivered || w.EndedAt == nil {
+		t.Fatalf("the end is said with its outcome: %+v", w)
+	}
+	want := []walkTouch{
+		{Machine: "novox", Modules: []string{"mesh-issues", "messenger", broker.RuntimeModule},
+			Carried: []string{"mesh-issues", "messenger"}},
+		{Machine: "shanks", Modules: []string{"gitea", broker.RuntimeModule}},
+	}
+	if !reflect.DeepEqual(w.Touches, want) {
+		t.Fatalf("touches:\n got %+v\nwant %+v", w.Touches, want)
+	}
+	for outcome, end := range map[string]func(*inventory.Plan){
+		inventory.WalkFailed: func(p *inventory.Plan) { p.State = inventory.PlanFailed },
+		inventory.WalkStopped: func(p *inventory.Plan) {
+			p.State, p.Delivery = inventory.PlanFailed, &inventory.PlanDelivery{Stopped: "a person"}
+		},
+	} {
+		q := p
+		end(&q)
+		if got := sayWalk(t.Context(), theMesh(), q).Outcome; got != outcome {
+			t.Errorf("outcome %q, want %q", got, outcome)
+		}
+	}
+}
+
+// novox/hq ADR 0308 How it is checked §1 and decision 5: the bound is twice the largest budget in force among
+// the walk's deliveries — 20 minutes for a core walk, twice the leaf budget for a leaf walk — and 15 minutes, not
+// doubled, for a walk none of whose deliveries has a budget.
+func TestAWalksBoundIsTwiceItsBudgetOrFifteenMinutesWithNone(t *testing.T) {
+	f := theMesh()
+	f.records = map[string]bool{"plex": true}
+	release := walkOfTiers("", []string{"gitea"})
+	release.Times, release.Release = &inventory.PlanTimes{}, &inventory.PlanRelease{Order: []string{"ace"}}
+	for name, c := range map[string]struct {
+		p     inventory.Plan
+		class string
+		bound int
+	}{
+		"core":                 {walkOfTiers(inventory.ClassCore, []string{"messenger"}), inventory.ClassCore, 1200},
+		"leaf":                 {walkOfTiers(inventory.ClassLeaf, []string{"messenger"}), inventory.ClassLeaf, int(2 * deliveryBudgets[inventory.ClassLeaf] / time.Second)},
+		"held for a person":    {walkOfTiers(inventory.ClassLeaf, []string{"plex"}), budgetNone, 900},
+		"a release":            {release, budgetNone, 900},
+		"kept without a class": {walkOfTiers("", []string{"messenger"}), budgetNone, 900},
+	} {
+		w := sayWalk(t.Context(), f, c.p)
+		if w.BudgetClass != c.class || w.BoundSeconds != c.bound {
+			t.Errorf("%s: %s bound %ds, want %s %ds", name, w.BudgetClass, w.BoundSeconds, c.class, c.bound)
+		}
+	}
+	// The leaf budget in force is three minutes (ADR 0304 decision 4): a leaf walk is bound at six.
+	if deliveryBudgets[inventory.ClassLeaf] == 3*time.Minute {
+		if w := sayWalk(t.Context(), f, walkOfTiers(inventory.ClassLeaf, []string{"messenger"})); w.BoundSeconds != 360 {
+			t.Errorf("a leaf walk at a three-minute budget is bound at 360 s: %d", w.BoundSeconds)
+		}
+	}
+}
+
+// plan-moved's body: the walk whole as before, and on its start the walk's fields beside it; on any other save
+// none of them.
+func TestPlanMovedCarriesTheWalkWholeAndOnItsStartWhatItTouches(t *testing.T) {
+	p := walkOfTiers(inventory.ClassLeaf, []string{"messenger"})
+	body, err := json.Marshal(planMovedBody{Plan: p, walkSaid: sayWalk(t.Context(), theMesh(), p)})
+	if err != nil {
+		t.Fatal(err)
+	}
+	var said map[string]any
+	if err := json.Unmarshal(body, &said); err != nil {
+		t.Fatal(err)
+	}
+	for _, k := range []string{"id", "state", "tiers", "modules", "times", "walk", "phase", "touches", "bound_seconds", "budget_class", "started_at"} {
+		if _, ok := said[k]; !ok {
+			t.Errorf("plan-moved lacks %q: %s", k, body)
+		}
+	}
+	if _, ok := said["outcome"]; ok {
+		t.Errorf("a start says no outcome: %s", body)
+	}
+	if said["walk"] != "plan-308" || said["phase"] != "started" || said["budget_class"] != "leaf" {
+		t.Errorf("the walk's fields: %s", body)
+	}
+	p.WalkSaid = ""
+	body, _ = json.Marshal(planMovedBody{Plan: p, walkSaid: sayWalk(t.Context(), theMesh(), p)})
+	said = map[string]any{}
+	_ = json.Unmarshal(body, &said)
+	for _, k := range []string{"walk", "phase", "touches", "bound_seconds"} {
+		if _, ok := said[k]; ok {
+			t.Errorf("a save neither starting nor ending the walk says %q: %s", k, body)
+		}
+	}
+	// A walk that touches nothing says an empty list, never null.
+	q := walkOfTiers(inventory.ClassLeaf, []string{"nobody-runs-this"})
+	body, _ = json.Marshal(planMovedBody{Plan: q, walkSaid: sayWalk(t.Context(), theMesh(), q)})
+	said = map[string]any{}
+	_ = json.Unmarshal(body, &said)
+	if touches, ok := said["touches"].([]any); !ok || len(touches) != 0 {
+		t.Errorf("touches nothing: %s", body)
+	}
+}
+
+// Live, with the store and a bus: a walk let go by the delivery's verb is said started with what it touches and
+// its bound, and stopped by the verb is said ended, stopped (novox/hq ADR 0308 How it is checked §1).
+func TestAWalkLetGoAndStoppedByVerbsIsSaidStartedAndEnded(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	next := planMovedHeard(t)
+	register(t, open, catalogue.Manifest{Module: "app", Version: "1"})
+	if _, err := assign(ctx, open, "anchor", "app"); err != nil {
+		t.Fatal(err)
+	}
+	cut := time.Now().UTC()
+	waiting := inventory.Plan{ID: "plan-308-live", Repository: "novox/mesh-catalog", Branch: "main", Commit: "c8c8c8c8",
+		Created: cut, State: inventory.PlanBuilding, Tiers: [][]string{{"app"}},
+		Modules:  map[string]*inventory.PlanModule{"app": {}},
+		Delivery: &inventory.PlanDelivery{Awaits: catalogue.DeliverySeat},
+		Times:    &inventory.PlanTimes{Cut: &cut, Class: inventory.ClassLeaf}}
+	if err := open.inventory.SavePlan(ctx, &waiting); err != nil {
+		t.Fatal(err)
+	}
+	if err := deliveryCommand(ctx, []string{"go", waiting.ID, "--why", "its turn"}); err != nil {
+		t.Fatal(err)
+	}
+	started := next(inventory.WalkStarted)
+	touches, _ := json.Marshal(started["touches"])
+	if started["walk"] != waiting.ID || string(touches) != `[{"machine":"anchor","modules":["app"]}]` ||
+		started["budget_class"] != inventory.ClassLeaf ||
+		started["bound_seconds"] != float64(2*deliveryBudgets[inventory.ClassLeaf]/time.Second) {
+		t.Fatalf("the start: %v", started)
+	}
+	if err := deliveryCommand(ctx, []string{"stop", waiting.ID, "--why", "a test", "--by", "a person"}); err != nil {
+		t.Fatal(err)
+	}
+	ended := next(inventory.WalkEnded)
+	touches, _ = json.Marshal(ended["touches"])
+	if ended["walk"] != waiting.ID || ended["outcome"] != inventory.WalkStopped || string(touches) != `[]` {
+		t.Fatalf("the end, which sent nothing: %v", ended)
+	}
+}
+
+// planMovedHeard raises a bus of the test's own, points the verbs' hand-act connection at it, and returns what
+// waits for the next plan-moved said with the given phase, failing the test when none comes within 5 s.
+func planMovedHeard(t *testing.T) func(phase string) map[string]any {
+	t.Helper()
+	js, err := broker.Dial(testbus.URL(t))
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(js.Close)
+	if err := broker.AssertMeshStreams(js); err != nil {
+		t.Fatal(err)
+	}
+	before := handActConn
+	handActConn = js.Conn()
+	t.Cleanup(func() { handActConn = before })
+	heard := make(chan *nats.Msg, 64)
+	sub, err := js.Conn().ChanSubscribe(link.SeatEventSubject(link.MeshControllerSeat, link.KeyPlanMoved), heard)
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { _ = sub.Unsubscribe() })
+	return func(phase string) map[string]any {
+		t.Helper()
+		deadline := time.After(5 * time.Second)
+		for {
+			select {
+			case m := <-heard:
+				var said map[string]any
+				if err := json.Unmarshal(m.Data, &said); err != nil {
+					t.Fatal(err)
+				}
+				if said["phase"] == phase {
+					return said
+				}
+			case <-deadline:
+				t.Fatalf("no walk was said %s", phase)
+			}
+		}
+	}
+}
+
+// Live, with the store and a bus: a walk a person stops with `plans stop` is said ended, outcome stopped, by the
+// verb itself, and is kept stopped by that person; `plans close` ends one the same way (novox/hq ADR 0308
+// decision 1, review 15 on mesh-controller#247).
+func TestAWalkStoppedOrClosedByAPersonIsSaidEndedStopped(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	next := planMovedHeard(t)
+	register(t, open, catalogue.Manifest{Module: "app", Version: "1"})
+	if _, err := assign(ctx, open, "anchor", "app"); err != nil {
+		t.Fatal(err)
+	}
+	for _, verb := range []string{"stop", "close"} {
+		cut := time.Now().UTC()
+		walk := inventory.Plan{ID: "plan-308-" + verb, Repository: "novox/mesh-catalog", Branch: "main",
+			Commit: "c8c8c8c8", Created: cut, State: inventory.PlanBuilding, Tiers: [][]string{{"app"}},
+			Modules: map[string]*inventory.PlanModule{"app": {}},
+			Times:   &inventory.PlanTimes{Cut: &cut, Started: &cut, Class: inventory.ClassLeaf}}
+		if err := open.inventory.SavePlan(ctx, &walk); err != nil {
+			t.Fatal(err)
+		}
+		if err := plansCommand(ctx, []string{verb, walk.ID, "--why", "a test"}); err != nil {
+			t.Fatal(err)
+		}
+		ended := next(inventory.WalkEnded)
+		if ended["walk"] != walk.ID || ended["outcome"] != inventory.WalkStopped {
+			t.Fatalf("plans %s: the end is %v", verb, ended)
+		}
+		p, err := open.inventory.PlanByID(ctx, walk.ID)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if p.Outcome() != inventory.WalkStopped || p.Delivery == nil || p.Delivery.StoppedWhy != "a test" {
+			t.Fatalf("plans %s kept the walk %s, %+v", verb, p.Outcome(), p.Delivery)
+		}
+	}
+}
+
+// Live, with the store and a bus: a failed walk retried with `plans retry` starts again, and the verb says its
+// start (novox/hq ADR 0308 decision 1, review 15 on mesh-controller#247).
+func TestAWalkRetriedByAPersonIsSaidStartedAgain(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	asksRecorded(t)
+	next := planMovedHeard(t)
+	twoTiers(t, open)
+	before := time.Now().UTC().Add(-time.Hour)
+	ended := before.Add(time.Minute)
+	failed := inventory.Plan{ID: "plan-308-retry", Repository: "novox/a", Branch: "main", Commit: "c0ffee",
+		Created: before, State: inventory.PlanFailed, Tier: 0, Tiers: [][]string{{"a"}, {"b"}},
+		Note: "a failed to build in tier 0",
+		Modules: map[string]*inventory.PlanModule{"a": {State: "failed", AskedAt: &before, Build: "build-1",
+			Why: link.KilledByHand}},
+		Times: &inventory.PlanTimes{Cut: &before, Started: &before, Ended: &ended, Class: inventory.ClassLeaf}}
+	if err := open.inventory.SavePlan(ctx, &failed); err != nil {
+		t.Fatal(err)
+	}
+	if err := plansCommand(ctx, []string{"retry", failed.ID}); err != nil {
+		t.Fatal(err)
+	}
+	started := next(inventory.WalkStarted)
+	if started["walk"] != failed.ID || started["budget_class"] != inventory.ClassLeaf {
+		t.Fatalf("the retried start: %v", started)
+	}
+}
+
+// Live, with the store and a bus: the release plan `upgrade release-backlog` opens is said started by the verb
+// (novox/hq ADR 0308 decision 1, review 15 on mesh-controller#247).
+func TestABacklogReleasedByAPersonIsSaidStarted(t *testing.T) {
+	b := aBacklog(t)
+	next := planMovedHeard(t)
+	if err := backlogCommand(t.Context(), "release-backlog", []string{"--why", "a test"}); err != nil {
+		t.Fatal(err)
+	}
+	started := next(inventory.WalkStarted)
+	if p := b.release(t); started["walk"] != p.ID {
+		t.Fatalf("the release's start: %v", started)
+	}
+}
+
+// asTyped runs a verb as the controller's command line runs it, through run, as a person's terminal would.
+func asTyped(t *testing.T, args ...string) error {
+	t.Helper()
+	was := os.Args
+	os.Args = append([]string{"mesh-controller"}, args...)
+	t.Cleanup(func() { os.Args = was })
+	err := run()
+	// run gives back the lease as the process would end; the test's process goes on, and takes it again.
+	theLease.mu.Lock()
+	theLease.held, theLease.kv, theLease.noBus = nil, nil, false
+	theLease.mu.Unlock()
+	return err
+}
+
+// aStartedWalkAsking keeps a live walk, said started, whose first tier asked a as build.
+func aStartedWalkAsking(t *testing.T, open *stores, id, build string, asked time.Time) inventory.Plan {
+	t.Helper()
+	walk := inventory.Plan{ID: id, Repository: "novox/a", Branch: "main", Commit: "c0ffee", Created: asked,
+		State: inventory.PlanBuilding, Tiers: [][]string{{"a"}, {"b"}},
+		Modules: map[string]*inventory.PlanModule{"a": {State: "asked", AskedAt: &asked, Build: build}},
+		Times:   &inventory.PlanTimes{Cut: &asked, Started: &asked, Class: inventory.ClassLeaf}}
+	if err := open.inventory.SavePlan(t.Context(), &walk); err != nil {
+		t.Fatal(err)
+	}
+	return walk
+}
+
+// Live, with the store and a bus: `cancel <build>` and `clear` fail the walk that asked the build, and the verb
+// says its end, failed (novox/hq ADR 0308 decision 1, review 21 on mesh-controller#247).
+func TestAWalkEndedByCancelOrClearIsSaidEnded(t *testing.T) {
+	_, ask := aBuildQueue(t)
+	open := aMesh(t)
+	next := planMovedHeard(t)
+	twoTiers(t, open)
+	for _, verb := range [][]string{{"cancel"}, {"clear"}} {
+		id := link.NewBuildID(time.Now())
+		ask(id, "https://forge.example/novox/a.git")
+		asked, _ := link.BuildAskedAt(id)
+		walk := aStartedWalkAsking(t, open, "plan-308-"+verb[0], id, asked)
+		args := verb
+		if verb[0] == "cancel" {
+			args = append(args, id)
+		}
+		if err := asTyped(t, args...); err != nil {
+			t.Fatal(err)
+		}
+		ended := next(inventory.WalkEnded)
+		if ended["walk"] != walk.ID || ended["outcome"] != inventory.WalkFailed {
+			t.Fatalf("%s: the end is %v", verb[0], ended)
+		}
+		// Ended, and so the next walk may be cut on the same repository.
+		p, _ := open.inventory.PlanByID(t.Context(), walk.ID)
+		if p.State != inventory.PlanFailed {
+			t.Fatalf("%s left the walk %s", verb[0], p.State)
+		}
+	}
+}
+
+// Live, with the store and a bus: `rebuild <module>` joining a failed walk sets it building again, and the verb
+// says its start (novox/hq ADR 0308 decision 1, review 21 on mesh-controller#247).
+func TestAWalkRestartedByARebuildIsSaidStarted(t *testing.T) {
+	open := aMesh(t)
+	asksRecorded(t)
+	next := planMovedHeard(t)
+	twoTiers(t, open)
+	before := time.Now().UTC().Add(-time.Hour)
+	ended := before.Add(time.Minute)
+	failed := inventory.Plan{ID: "plan-308-rebuild", Repository: "novox/a", Branch: "main", Commit: "c0ffee",
+		Created: before, State: inventory.PlanFailed, Tiers: [][]string{{"a"}, {"b"}},
+		Modules: map[string]*inventory.PlanModule{"a": {State: "failed", AskedAt: &before, Build: "build-1",
+			Why: link.CancelledByHand}},
+		Times: &inventory.PlanTimes{Cut: &before, Started: &before, Ended: &ended, Class: inventory.ClassLeaf}}
+	if err := open.inventory.SavePlan(t.Context(), &failed); err != nil {
+		t.Fatal(err)
+	}
+	if err := asTyped(t, "rebuild", "a"); err != nil {
+		t.Fatal(err)
+	}
+	if started := next(inventory.WalkStarted); started["walk"] != failed.ID {
+		t.Fatalf("the rebuilt walk's start: %v", started)
+	}
+}
+
+// Live, with the store: a walk a person stopped and then retried, by `plans retry` or by `rebuild`, walks again
+// without the stop, so when it fails again it ends failed, not stopped, and the search for the merge that
+// brought the failure is not kept from it (novox/hq ADR 0308 decision 1, review 21 on mesh-controller#247).
+func TestAWalkStoppedByHandAndRetriedEndsFailedWhenItFailsAgain(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	asksRecorded(t)
+	twoTiers(t, open)
+	for _, again := range [][]string{{"plans", "retry"}, {"rebuild", "a"}} {
+		before := time.Now().UTC().Add(-time.Hour)
+		walk := aStartedWalkAsking(t, open, "plan-308-again-"+again[0], "build-1", before)
+		if err := asTyped(t, "plans", "stop", walk.ID, "--why", "a test"); err != nil {
+			t.Fatal(err)
+		}
+		// The build asked before the stop fails after it.
+		p, _ := open.inventory.PlanByID(ctx, walk.ID)
+		p.Modules["a"].State, p.Modules["a"].Why = "failed", "it broke"
+		if err := open.inventory.SavePlan(ctx, &p); err != nil {
+			t.Fatal(err)
+		}
+		args := again
+		if again[0] == "plans" {
+			args = append(append([]string(nil), again...), walk.ID)
+		}
+		if err := asTyped(t, args...); err != nil {
+			t.Fatal(err)
+		}
+		p, _ = open.inventory.PlanByID(ctx, walk.ID)
+		if p.State != inventory.PlanBuilding || (p.Delivery != nil && p.Delivery.Stopped != "") {
+			t.Fatalf("%s: the walk is %s and keeps its stop: %+v", again[0], p.State, p.Delivery)
+		}
+		asking, _ := link.BuildAskedAt(p.Modules["a"].Build)
+		planBuilt(ctx, open, "a", "c0ffee", "it broke again", asking, p.Modules["a"].Build)
+		if p, _ = open.inventory.PlanByID(ctx, walk.ID); p.State != inventory.PlanFailed || p.Outcome() != inventory.WalkFailed {
+			t.Fatalf("%s: failing again, the walk is %s and ends %s", again[0], p.State, p.Outcome())
+		}
+	}
+}

cmd/mesh-controller/watchdogs.go

@@ -59,6 +59,10 @@ type signalFacts struct {
 	// from, each naming its sender (S20, novox/hq issue 234).
 	refusedSends    []inventory.Send
 	refusedSendsErr error
+	// doing is every machine whose last report was not a clean apply, with since when it has said the same
+	// failure (S21, novox/hq issue 233).
+	doing    []inventory.Doing
+	doingErr error
 
 	loop    loopFacts
 	loopErr error
@@ -369,6 +373,7 @@ func (w *watchdogs) gather(ctx context.Context) *signalFacts {
 	}
 	f.handActs, f.handActsErr = w.gatherHandActs(ctx, now)
 	f.refusedSends, f.refusedSendsErr = inv.RefusedSendsSince(ctx, now.Add(-generationRefusalsSaid))
+	f.doing, f.doingErr = inv.NotDoingWhatTheyWereTold(ctx)
 	f.facts.taken, _, f.facts.began, f.facts.err = exportedFacts.last()
 	return f
 }
@@ -734,6 +739,9 @@ func watchTheMesh(ctx context.Context, open *stores, server *link.Server, bus li
 	// and the answer chosen is performed on its warrant.
 	startAsking(watching, open, server, bus.Conn, keeper)
 	go forgettingOldHeals(watching, open.inventory)
+	// And the build queue's order (novox/hq issue 558): a check that has waited its while goes ahead of the
+	// deliveries asked after it even when nothing new is asked.
+	go keepingTheQueueInOrder(watching, open, server.JetStream())
 	fmt.Printf("watching the mesh: %d signal(s) every %s, %d probe(s) every %s; what is wrong is kept in %s "+
 		"and said as %s events\n", len(watchedRows()), watchEvery, len(runnableProbes()), doctorEvery,
 		broker.ConditionsBucket, conditions.Seat)

go.mod

@@ -8,6 +8,7 @@ require (
 	github.com/nats-io/nats-server/v2 v2.11.17
 	github.com/nats-io/nats.go v1.54.0
 	github.com/novox/mesh-host v0.0.0
+	github.com/therootcompany/xz v1.0.1
 	golang.org/x/crypto v0.57.0
 	golang.org/x/net v0.58.0
 	golang.org/x/sys v0.48.0

go.sum

@@ -38,6 +38,8 @@ github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UV
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
 github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
+github.com/therootcompany/xz v1.0.1 h1:CmOtsn1CbtmyYiusbfmhmkpAAETj0wBIH6kCYaX+xzw=
+github.com/therootcompany/xz v1.0.1/go.mod h1:3K3UH1yCKgBneZYhuQUvJ9HPD19UEXEI0BWbMn8qNMY=
 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/net v0.58.0 h1:ynWG7rqYi4ccpTEuPZ2QGWHktVEM9DMCj9yzDE0Q7To=

internal/broker/nats.go

@@ -262,9 +262,12 @@ func MaySubscribe(perms Permissions, subject string) bool {
 // delivery held past its bound, and calls them on the operator's warrant, with its why.
 //
 // And, since novox/hq ADR 0282, `times`: the self-check reads the delivery times to say a delivery over its budget.
+//
+// And, since novox/hq ADR 0306, `groups`: a merge heard from a head waits for the window while its delivery group
+// has a member still to merge.
 var VerbsTheControllerAsksTheDeliveryOwner = []SeatVerb{{Seat: "mesh-delivery", Verb: "stalled"},
 	{Seat: "mesh-delivery", Verb: "close"}, {Seat: "mesh-delivery", Verb: "release"}, {Seat: "mesh-delivery", Verb: "stop"},
-	{Seat: "mesh-delivery", Verb: "times"}}
+	{Seat: "mesh-delivery", Verb: "times"}, {Seat: "mesh-delivery", Verb: "groups"}}
 
 // VerbsTheControllerActsOnAWarrant are the other seat verbs the controller calls when the operator's warrant
 // chooses them (novox/hq ADR 0259): a machine's service restarted, and a walk started or stopped through the
@@ -333,6 +336,13 @@ func AskHandOverSubject(node string) string { return "mesh.node." + node + ".ask
 // a hand-over is (link.SetuidSearchContext), for the same reason.
 func AskSetuidSearchSubject(node string) string { return "mesh.node." + node + ".ask.setuid-search" }
 
+// AskJudgeDirectoriesSubject is where the controller asks one machine's node-engine to judge, read-only, which of
+// its declared directories the walk that follows no link another account could make would refuse (novox/hq issue
+// 358): a request answered once, signed as a hand-over is (link.JudgeDirectoriesContext), for the same reason.
+func AskJudgeDirectoriesSubject(node string) string {
+	return "mesh.node." + node + ".ask.judge-directories"
+}
+
 // inbox is a principal's own reply space. No user is ever granted a bare `_INBOX.>` (design 25
 // §4): with one account, inbox privacy is the permission list or it is nothing, so each user's
 // inbox is derived from its own identity and its permissions name that prefix and no other.
@@ -611,7 +621,9 @@ func PermissionsFor(p Principal) (Permissions, error) {
 			// issue 356), which it answers on the request's reply: the one request a node is asked.
 			AskHandOverSubject(p.Node),
 			// And asking it for a fresh search for setuid programs (novox/hq issue 361), answered the same way.
-			AskSetuidSearchSubject(p.Node)}
+			AskSetuidSearchSubject(p.Node),
+			// And asking it to judge its declared directories, read-only (novox/hq issue 358), answered the same way.
+			AskJudgeDirectoriesSubject(p.Node)}
 		// The node-engine witnesses the core builds it places (novox/hq to-be 45 §8, ADR 0236; the
 		// contract is lease/witness.go): it asks its own machine's node tools PING, and, where the
 		// machine runs the controller, reads the lease's one key — read, never written.

internal/broker/nats_test.go

@@ -114,7 +114,9 @@ func TestOnlyWhatCanBeAskedMayAnswer(t *testing.T) {
 	node, _ := PermissionsFor(Principal{Kind: KindNode, Node: "one", PasswordHash: "x"})
 	if !node.AllowResponses || !slices.Contains(node.Subscribe, AskHandOverSubject("one")) ||
 		!slices.Contains(node.Subscribe, AskSetuidSearchSubject("one")) ||
-		slices.Contains(node.Subscribe, AskSetuidSearchSubject("two")) {
+		slices.Contains(node.Subscribe, AskSetuidSearchSubject("two")) ||
+		!slices.Contains(node.Subscribe, AskJudgeDirectoriesSubject("one")) ||
+		slices.Contains(node.Subscribe, AskJudgeDirectoriesSubject("two")) {
 		t.Fatalf("a node cannot answer the hand-over it is asked: %v %v", node.AllowResponses, node.Subscribe)
 	}
 	person, _ := PermissionsFor(Principal{Kind: KindPerson, Node: "one", Module: "jo", PasswordHash: "x"})

internal/broker/testdata/composed.conf

@@ -24,7 +24,7 @@ accounts {
     jetstream: enabled
     users = [
       { user: "controller", password: "$2a$11$cccccccccccccccccccccc", permissions: {
-        publish: { allow: ["$JS.ACK.CONTROL.controller.>", "$JS.ACK.DEAD_LETTER_NOTICES.controller.>", "$JS.ACK.EVENTS.controller.>", "$JS.API.>", "$KV.SEAT_MESH_BUILD_MACHINE_cancelled.>", "$KV.SEAT_NODE_BUILD_AGENT_cancelled.>", "$KV.mesh-controller_asked.>", "$KV.mesh-controller_calls.>", "$KV.mesh-controller_condition-history.>", "$KV.mesh-controller_conditions.>", "$KV.mesh-controller_hand-acts.>", "$KV.mesh-controller_lease.>", "$SRV.INFO", "_INBOX.enrol.>", "mesh.again.>", "mesh.assignment.>", "mesh.events.dead.>", "mesh.mod.*.tool.>", "mesh.node.>", "mesh.seat.mesh-build-machine.accept.>", "mesh.seat.mesh-build-machine.tool.>", "mesh.seat.mesh-controller.event.applied", "mesh.seat.mesh-controller.event.built-before", "mesh.seat.mesh-controller.event.checked", "mesh.seat.mesh-controller.event.condition-changed", "mesh.seat.mesh-controller.event.condition-cleared", "mesh.seat.mesh-controller.event.condition-raised", "mesh.seat.mesh-controller.event.doctor-heartbeat", "mesh.seat.mesh-controller.event.healer-acted", "mesh.seat.mesh-controller.event.plan-moved", "mesh.seat.mesh-controller.event.refused", "mesh.seat.mesh-controller.event.rolled-back", "mesh.seat.mesh-controller.event.secret-replaced", "mesh.seat.mesh-controller.tool.plans", "mesh.seat.mesh-delivery.tool.close", "mesh.seat.mesh-delivery.tool.release", "mesh.seat.mesh-delivery.tool.stalled", "mesh.seat.mesh-delivery.tool.stop", "mesh.seat.mesh-delivery.tool.times", "mesh.seat.node-backup.tool.backed-up.*", "mesh.seat.node-backup.tool.now.*", "mesh.seat.node-build-agent.accept.>", "mesh.seat.node-build-agent.tool.>", "mesh.seat.node-intrusion-prevention.tool.banned.*", "mesh.seat.node-launcher.tool.secret.*", "mesh.seat.node-service-manager.tool.restart.*"] }
+        publish: { allow: ["$JS.ACK.CONTROL.controller.>", "$JS.ACK.DEAD_LETTER_NOTICES.controller.>", "$JS.ACK.EVENTS.controller.>", "$JS.API.>", "$KV.SEAT_MESH_BUILD_MACHINE_cancelled.>", "$KV.SEAT_NODE_BUILD_AGENT_cancelled.>", "$KV.mesh-controller_asked.>", "$KV.mesh-controller_calls.>", "$KV.mesh-controller_condition-history.>", "$KV.mesh-controller_conditions.>", "$KV.mesh-controller_hand-acts.>", "$KV.mesh-controller_lease.>", "$SRV.INFO", "_INBOX.enrol.>", "mesh.again.>", "mesh.assignment.>", "mesh.events.dead.>", "mesh.mod.*.tool.>", "mesh.node.>", "mesh.seat.mesh-build-machine.accept.>", "mesh.seat.mesh-build-machine.tool.>", "mesh.seat.mesh-controller.event.applied", "mesh.seat.mesh-controller.event.built-before", "mesh.seat.mesh-controller.event.checked", "mesh.seat.mesh-controller.event.condition-changed", "mesh.seat.mesh-controller.event.condition-cleared", "mesh.seat.mesh-controller.event.condition-raised", "mesh.seat.mesh-controller.event.doctor-heartbeat", "mesh.seat.mesh-controller.event.healer-acted", "mesh.seat.mesh-controller.event.plan-moved", "mesh.seat.mesh-controller.event.refused", "mesh.seat.mesh-controller.event.rolled-back", "mesh.seat.mesh-controller.event.secret-replaced", "mesh.seat.mesh-controller.tool.plans", "mesh.seat.mesh-delivery.tool.close", "mesh.seat.mesh-delivery.tool.groups", "mesh.seat.mesh-delivery.tool.release", "mesh.seat.mesh-delivery.tool.stalled", "mesh.seat.mesh-delivery.tool.stop", "mesh.seat.mesh-delivery.tool.times", "mesh.seat.node-backup.tool.backed-up.*", "mesh.seat.node-backup.tool.now.*", "mesh.seat.node-build-agent.accept.>", "mesh.seat.node-build-agent.tool.>", "mesh.seat.node-intrusion-prevention.tool.banned.*", "mesh.seat.node-launcher.tool.secret.*", "mesh.seat.node-service-manager.tool.restart.*"] }
         subscribe: { allow: ["$JS.API.>", "$JS.EVENT.ADVISORY.CONSUMER.DELETED.>", "$JS.EVENT.ADVISORY.CONSUMER.MAX_DELIVERIES.>", "$SRV.INFO", "$SRV.INFO.mesh-controller", "$SRV.INFO.mesh-controller.>", "$SRV.PING", "$SRV.PING.mesh-controller", "$SRV.PING.mesh-controller.>", "$SRV.STATS", "$SRV.STATS.mesh-controller", "$SRV.STATS.mesh-controller.>", "_DELIVER.controller", "_DELIVER.controller.>", "_INBOX.controller.>", "mesh.control.>", "mesh.mod.*.event.provisioner.failing", "mesh.mod.*.event.provisioner.recovered", "mesh.mod.*.event.provisioner.retirement", "mesh.mod.gitea.event.pull.merged", "mesh.mod.gitea.event.pull.updated", "mesh.mod.mesh-catalog.event.catching-up", "mesh.mod.mesh-catalog.event.upgraded", "mesh.seat.mesh-build-machine.event.built", "mesh.seat.mesh-controller.tool.>", "mesh.seat.node-build-agent.event.built", "mesh.seat.operator-channel.event.decided.mesh-controller"] }
         allow_responses: { max: 1, ttl: "1m" }
       } }
@@ -34,7 +34,7 @@ accounts {
       } }
       { user: "node.one", password: "$2a$11$nnnnnnnnnnnnnnnnnnnnnn", permissions: {
         publish: { allow: ["$JS.ACK.NODES.one.>", "$JS.API.CONSUMER.INFO.NODES.one", "$SRV.PING.node-tools.one", "mesh.control.one.>"] }
-        subscribe: { allow: ["_DELIVER.one", "_DELIVER.one.>", "_INBOX.node.one.>", "mesh.node.one.ask.hand-over", "mesh.node.one.ask.report", "mesh.node.one.ask.setuid-search", "mesh.node.one.declare"] }
+        subscribe: { allow: ["_DELIVER.one", "_DELIVER.one.>", "_INBOX.node.one.>", "mesh.node.one.ask.hand-over", "mesh.node.one.ask.judge-directories", "mesh.node.one.ask.report", "mesh.node.one.ask.setuid-search", "mesh.node.one.declare"] }
         allow_responses: { max: 1, ttl: "1m" }
       } }
       { user: "one.nats", password: "$2a$11$bbbbbbbbbbbbbbbbbbbbbb", permissions: {

internal/broker/writers.go

@@ -96,6 +96,11 @@ var WritersTable = []WriterRow{
 	{State: "a fresh setuid search asked of a machine", Writer: "controller, at its terminal",
 		KeptIn: "the machine, which throws its last search away", Others: "the engine verifies the mesh's signature and starts it, or refuses",
 		Subjects: []string{"mesh.node.*.ask.setuid-search"}, Writes: isController},
+	// A read-only judgement of a machine's declared directories asked of its engine (novox/hq issue 358): signed as a
+	// hand-over is, under a signing context of its own. It changes nothing on the machine.
+	{State: "a judgement of a machine's directories asked of it", Writer: "controller",
+		KeptIn: "nowhere: the engine answers it and keeps nothing", Others: "the engine verifies the mesh's signature and answers, or refuses",
+		Subjects: []string{"mesh.node.*.ask.judge-directories"}, Writes: isController},
 	{State: "a machine's applied state and its report", Writer: "the node-engine's apply queue",
 		KeptIn: "the machine; the report on the bus", Others: "the reconcile and a delivery enqueue, never apply",
 		// And its health statement between reports (novox/hq ADR 0240): the same writer stating the same

internal/broker/writers_test.go

@@ -17,6 +17,7 @@ var designRows = []string{
 	"a machine's declaration",
 	"a hand-over asked of a machine",
 	"a fresh setuid search asked of a machine",
+	"a judgement of a machine's directories asked of it",
 	"a machine's applied state and its report",
 	"the controller lease",
 	"plans and their tiers",
@@ -186,3 +187,21 @@ func TestASetuidSearchAskHasOnePublisher(t *testing.T) {
 		}
 	}
 }
+
+// **A judgement of a machine's directories asked of it has one publisher, the controller** (novox/hq issue 358), as a
+// hand-over has.
+func TestADirectoryJudgementAskHasOnePublisher(t *testing.T) {
+	for _, p := range []Principal{
+		{Kind: KindNode, Node: "laptop"},
+		{Kind: KindNodeTools, Node: "laptop", Module: RuntimeModule},
+		{Kind: KindModule, Node: "laptop", Module: "notes"},
+	} {
+		err := CheckWriters(p, []string{AskJudgeDirectoriesSubject("laptop")})
+		if err == nil || !strings.Contains(err.Error(), "a judgement of a machine's directories asked of it") {
+			t.Errorf("%s may ask a judgement of directories: %v", p.Username(), err)
+		}
+	}
+	if err := CheckWriters(Principal{Kind: KindController}, []string{AskJudgeDirectoriesSubject("laptop")}); err != nil {
+		t.Fatalf("the controller may not ask a judgement: %v", err)
+	}
+}

internal/builder/builder.go

@@ -971,8 +971,19 @@ func one(ctx context.Context, run Runner, publish Publisher,
 		return catalogue.Built{Name: a.Name, Kind: a.Kind, Reference: reference}, nil
 
 	case catalogue.ArtifactArchive:
-		src.ownHas(cleanEntry(a.From) + "/**")
-		body, err := pack(filepath.Join(tree, a.From))
+		var body []byte
+		var err error
+		if a.URL != "" {
+			// An upstream file pinned by URL and sha256 (novox/hq ADR 0316): its build source is the pin, which
+			// is in module.json, always part of it.
+			body, err = upstreamArchive(ctx, workspace, a, say)
+			if err != nil {
+				return catalogue.Built{}, fmt.Errorf("%s: %s: %w", module, a.Name, err)
+			}
+		} else {
+			src.ownHas(cleanEntry(a.From) + "/**")
+			body, err = pack(filepath.Join(tree, a.From))
+		}
 		if err != nil {
 			return catalogue.Built{}, fmt.Errorf("%s: packing %s failed: %w", module, a.Name, err)
 		}

internal/builder/check.go

@@ -49,8 +49,10 @@ import (
 //
 // One check:
 //
-//  1. clones the repository at the pull request's head, and beside it the repositories its check
-//     reads — the controller the mesh runs, the catalogue, the host, the lab — each at the ref asked;
+//  1. clones the repository at the pull request's head and **makes the merge of that head into the trunk's
+//     head**, the check's trunk commit, in its own clone (novox/hq ADR 0323, issue 341; check_merge.go): what
+//     is judged is what merging makes, never pushed. Beside it the repositories its check reads — the
+//     controller the mesh runs, the catalogue, the host, the lab — each at the ref asked;
 //  2. reads the facts snapshot the controller keeps, and with it **the versions the mesh runs**: the
 //     store a check's tests stand on is the store's own release, and the bus the bus's;
 //  3. raises a throwaway PostgreSQL and a throwaway bus of those versions, labelled with the ask so a
@@ -79,7 +81,8 @@ type CheckSpec struct {
 	Modules   []string
 	New       []string
 	Manifests []string
-	// Base is the branch the pull request merges into: what the gate compares the change against.
+	// Base is the branch the pull request merges into: what the gate compares the change against, and the trunk
+	// whose head the change is merged into before it is judged (novox/hq ADR 0323). Empty judges the head alone.
 	Base string
 	// Judge is who judges the gate: "" the controller the mesh runs, "self" the change's own, "validator"
 	// the running one with the change's validator.
@@ -104,6 +107,9 @@ type GroupHead struct {
 	Repository string
 	Ref        string
 	Paths      []string
+	// Base is the branch it merges into: the head is merged into that trunk's head before it is composed
+	// (novox/hq ADR 0323 §6). Empty composes the head alone, as a controller from before it asks.
+	Base string
 }
 
 // Gated is whether the change touches the mesh's graph, and so whether the gate runs.
@@ -139,6 +145,16 @@ type CheckVerdict struct {
 	Took    time.Duration
 	Gate    *Layer
 	Repo    *Layer
+	// Head and Trunk are what was judged (novox/hq ADR 0323 §3): the pull request's head merged into the trunk
+	// commit, each as twelve characters. Trunk is empty for a check asked with no trunk, which judged the head
+	// alone. Merge is the merge commit made for the check, whole: only checked, never pushed or registered.
+	Head, Trunk, Merge string
+	// Beside are the commits of the repositories the check read beside its own, by the directory each was
+	// cloned under, as twelve characters: named, not judged against (ADR 0323 §3, issue 568).
+	Beside map[string]string
+	// Members are a delivery group's other heads as the composed check judged them, each with the trunk
+	// commit it was merged into (ADR 0323 §6).
+	Members []JudgedHead
 }
 
 // Layer is one layer of a check, judged.
@@ -281,6 +297,34 @@ func Check(ctx context.Context, run Runner, spec CheckSpec, workspace, registry
 		return CheckVerdict{}, err
 	}
 	tree := filepath.Join(root, name)
+	// **What merging makes is judged, not the head** (novox/hq ADR 0323, issue 341): the head merged into the
+	// trunk's head as this clone found it, in this clone alone. A head that does not merge cleanly fails here.
+	judged := CheckVerdict{Head: twelve(spec.Ref)}
+	paths := spec.Paths
+	if spec.Base != "" {
+		m, err := mergeIntoTrunk(ctx, run, tree, spec.Base, spec.Ref)
+		if err != nil {
+			return CheckVerdict{}, err
+		}
+		judged.Head, judged.Trunk = twelve(m.Head), twelve(m.Trunk)
+		if len(m.Conflicts) > 0 {
+			said := conflictWords(m)
+			say("check", "%s", said)
+			return CheckVerdict{Verdict: "fail", Summary: said, Report: said, Took: time.Since(began),
+				Gate: &Layer{Verdict: "fail", Summary: said}, Repo: &Layer{Verdict: "fail", Summary: said},
+				Head: judged.Head, Trunk: judged.Trunk}, nil
+		}
+		judged.Merge = m.Merge
+		if changed := changedByMerge(ctx, run, tree, m); len(changed) > 0 {
+			paths = changed
+		}
+		say("check", "head %s merged into trunk %s (%s): the merge is judged, and never pushed", judged.Head,
+			judged.Trunk, spec.Base)
+	}
+	named := func(v CheckVerdict) CheckVerdict {
+		v.Head, v.Trunk, v.Merge, v.Beside, v.Members = judged.Head, judged.Trunk, judged.Merge, judged.Beside, judged.Members
+		return v
+	}
 	// **The base branch's check judges the change** (novox/hq issue 310), never the one the change brings.
 	judging, err := TheCheckThatJudges(ctx, tree, spec.Base)
 	if err != nil {
@@ -297,7 +341,7 @@ func Check(ctx context.Context, run Runner, spec CheckSpec, workspace, registry
 		v := CheckVerdict{Verdict: "pass", Summary: noModule, Took: time.Since(began),
 			Gate: &Layer{Verdict: "pass", Summary: noModule}, Repo: &Layer{Verdict: "warning", Summary: noScript}}
 		say("check", "%s; %s", noModule, noScript)
-		return v, nil
+		return named(v), nil
 	}
 	for dir, b := range spec.Beside {
 		if dir == name || !safeName.MatchString(dir) {
@@ -306,6 +350,13 @@ func Check(ctx context.Context, run Runner, spec CheckSpec, workspace, registry
 		if err := clone(b.Repository, b.Ref, dir); err != nil {
 			return CheckVerdict{}, fmt.Errorf("beside it, %w", err)
 		}
+		// The commit each one read is named in the verdict (ADR 0323 §3): its move is issue 568's question.
+		if at := headAt(ctx, run, filepath.Join(root, dir)); at != "" {
+			if judged.Beside == nil {
+				judged.Beside = map[string]string{}
+			}
+			judged.Beside[dir] = at
+		}
 		say("check", "beside it %s at %s", dir, short(b.Ref))
 	}
 
@@ -322,6 +373,26 @@ func Check(ctx context.Context, run Runner, spec CheckSpec, workspace, registry
 				return CheckVerdict{}, fmt.Errorf("a head of the group, %w", err)
 			}
 			say("check", "with it, of its group, %s/%s at %s", g.Owner, g.Repo, short(g.Ref))
+			// Each member is composed as its merge into its own trunk's head (ADR 0323 §6).
+			member := JudgedHead{Owner: g.Owner, Repo: g.Repo, Head: twelve(g.Ref)}
+			if g.Base != "" {
+				m, err := mergeIntoTrunk(ctx, run, filepath.Join(root, dir), g.Base, g.Ref)
+				if err != nil {
+					return CheckVerdict{}, fmt.Errorf("a head of the group, %s/%s: %w", g.Owner, g.Repo, err)
+				}
+				member.Head, member.Trunk = twelve(m.Head), twelve(m.Trunk)
+				if len(m.Conflicts) > 0 {
+					said := fmt.Sprintf("%s/%s: %s", g.Owner, g.Repo, conflictWords(m))
+					say("check", "%s", said)
+					judged.Members = append(judged.Members, member)
+					return named(CheckVerdict{Verdict: "fail", Summary: said, Report: said, Took: time.Since(began),
+						Gate: &Layer{Verdict: "fail", Summary: said}, Repo: &Layer{Verdict: "fail", Summary: said}}), nil
+				}
+				if changed := changedByMerge(ctx, run, filepath.Join(root, dir), m); len(changed) > 0 {
+					g.Paths = changed
+				}
+			}
+			judged.Members = append(judged.Members, member)
 			heads = append(heads, map[string]any{"repository": g.Owner + "/" + g.Repo,
 				"tree": filepath.Join(root, dir), "changed": g.Paths})
 		}
@@ -433,7 +504,7 @@ func Check(ctx context.Context, run Runner, spec CheckSpec, workspace, registry
 	verdictFile := filepath.Join(root, "verdict.json")
 	env := []string{EnvFacts + "=" + factsFile, EnvGate + "=" + gate, EnvGateStore + "=" + storeURL,
 		EnvTestStore + "=" + storeURL, EnvTestBus + "=nats://" + bus, EnvRepository + "=" + spec.Owner + "/" + spec.Repo,
-		EnvChanged + "=" + strings.Join(spec.Paths, ","), EnvBeside + "=" + root,
+		EnvChanged + "=" + strings.Join(paths, ","), EnvBeside + "=" + root,
 		EnvModules + "=" + strings.Join(append(append([]string{}, spec.Modules...), spec.New...), ","),
 		EnvGroup + "=" + groupFile,
 		"GOCACHE=" + filepath.Join(workspace, "go-cache"), "GOMODCACHE=" + filepath.Join(workspace, "go-modules")}
@@ -501,7 +572,7 @@ func Check(ctx context.Context, run Runner, spec CheckSpec, workspace, registry
 	v.Report, v.Took = redact.redact(withWhatFailed(out.String(), v.Repo)), time.Since(began)
 	say("check", "gate %s — %s; repository %s — %s (%s)", strings.ToUpper(v.Gate.Verdict), v.Gate.Summary,
 		strings.ToUpper(v.Repo.Verdict), v.Repo.Summary, v.Took.Round(time.Second))
-	return v, nil
+	return named(v), nil
 }
 
 // ownCheck runs the repository's own check, part by part, each in its toolchain's own container: the

internal/builder/check_merge.go

@@ -0,0 +1,115 @@
+package builder
+
+import (
+	"context"
+	"fmt"
+	"strings"
+)
+
+// **A merge check judges the merge, not the head** (novox/hq ADR 0323, issue 341).
+//
+// On 2026-10-09 a node-engine pull request was checked green at its head and broke the trunk when it merged:
+// a merge an hour earlier had added a field under the same JSON key on other lines, git merged the two edits
+// without a conflict, and the result did not compile. The check had judged the head alone. So a check now
+// takes the trunk the pull request merges into, its head at the moment the check clones it as the check's
+// **trunk commit**, and makes in its own clone the merge of the head into that commit, as the forge's
+// default merge would. The gate and the repository's own check judge that merge.
+//
+// **The merge is only checked** (ADR 0323 §2, ADR 0238 §1): it is a commit off the trunk, made in the
+// check's own clone, never pushed to the forge and never registered; the clone is removed when the check
+// ends. Nothing here writes to a remote.
+//
+// The forge keeps no merge reference for a pull request, only its head, so the builder makes it itself.
+
+// TrunkMerge is the merge a check made: the head and the trunk commit it was merged into, whole, and the merge
+// commit; or the files in conflict when the head does not merge cleanly.
+type TrunkMerge struct {
+	Head, Trunk, Merge string
+	Conflicts          []string
+}
+
+// JudgedHead is one head a check judged, with the trunk commit it merged that head into, each as twelve
+// characters (ADR 0323 §3, §6).
+type JudgedHead struct {
+	Owner, Repo string
+	Head, Trunk string
+}
+
+// mergeIdentity is who a check's merge is made as: it is never pushed, so it names nobody's account. No hook of the
+// clone's or the build machine's git configuration runs, and no setting there changes the merge.
+var mergeIdentity = []string{"-c", "user.name=mesh merge check", "-c", "user.email=merge-check@mesh.invalid",
+	"-c", "commit.gpgsign=false", "-c", "core.hooksPath=/dev/null", "-c", "merge.verifySignatures=false"}
+
+// mergeIntoTrunk makes, in the clone at tree, the merge of head into the head of origin/<base> as it stands in
+// that fresh clone: the trunk commit. A head that does not merge cleanly answers the files in conflict and leaves
+// the tree at the trunk commit; an error is that the merge could not be tried at all.
+func mergeIntoTrunk(ctx context.Context, run Runner, tree, base, head string) (TrunkMerge, error) {
+	var m TrunkMerge
+	revParse := func(ref string) (string, error) {
+		out, err := run(ctx, tree, "git", "rev-parse", "--verify", "--quiet", ref+"^{commit}")
+		return strings.TrimSpace(out), err
+	}
+	var err error
+	if m.Head, err = revParse(head); err != nil || m.Head == "" {
+		return m, fmt.Errorf("the head %s cannot be read in the check's clone: %v", head, err)
+	}
+	if m.Trunk, err = revParse("refs/remotes/origin/" + base); err != nil || m.Trunk == "" {
+		return m, fmt.Errorf("the trunk %s cannot be read, and a check judges the head merged into it "+
+			"(novox/hq ADR 0323): %v", base, err)
+	}
+	if _, err := run(ctx, tree, "git", "checkout", "--quiet", "--detach", m.Trunk); err != nil {
+		return m, fmt.Errorf("the trunk commit %s cannot be checked out: %w", twelve(m.Trunk), err)
+	}
+	message := fmt.Sprintf("Check the merge of %s into %s at %s (made for a merge check, never pushed)",
+		twelve(m.Head), base, twelve(m.Trunk))
+	args := append(append([]string{}, mergeIdentity...), "merge", "--no-ff", "--no-edit", "--no-verify", "--quiet", "-m", message, m.Head)
+	if _, err := run(ctx, tree, "git", args...); err != nil {
+		out, _ := run(ctx, tree, "git", "diff", "--name-only", "--diff-filter=U")
+		m.Conflicts = strings.Fields(out)
+		_, _ = run(ctx, tree, "git", "merge", "--abort")
+		if len(m.Conflicts) == 0 {
+			return m, fmt.Errorf("the head %s could not be merged into trunk %s: %w", twelve(m.Head), twelve(m.Trunk), err)
+		}
+		return m, nil
+	}
+	if m.Merge, err = revParse("HEAD"); err != nil {
+		return m, fmt.Errorf("the merge made for the check cannot be read: %w", err)
+	}
+	return m, nil
+}
+
+// changedByMerge is every path the merge changes against the trunk commit: what the gate's delivery plan is
+// computed from (ADR 0323 §1). Nil when it cannot be read; the caller keeps the pull request's own list.
+func changedByMerge(ctx context.Context, run Runner, tree string, m TrunkMerge) []string {
+	if m.Merge == "" || m.Trunk == "" {
+		return nil
+	}
+	out, err := run(ctx, tree, "git", "diff", "--name-only", "--no-renames", m.Trunk, m.Merge)
+	if err != nil {
+		return nil // empty-on-error: the caller keeps the pull request's own list of changed files, the safe one
+	}
+	return strings.Fields(out)
+}
+
+// conflictWords is a head that does not merge cleanly, said as its check's failure.
+func conflictWords(m TrunkMerge) string {
+	return fmt.Sprintf("head %s does not merge cleanly into trunk %s: in conflict %s", twelve(m.Head), twelve(m.Trunk),
+		strings.Join(m.Conflicts, ", "))
+}
+
+// headAt is the commit a clone is checked out at, as twelve characters; empty when it cannot be read.
+func headAt(ctx context.Context, run Runner, tree string) string {
+	out, err := run(ctx, tree, "git", "rev-parse", "--verify", "--quiet", "HEAD^{commit}")
+	if err != nil {
+		return ""
+	}
+	return twelve(strings.TrimSpace(out))
+}
+
+// twelve is a commit as a verdict names it: its first twelve characters.
+func twelve(commit string) string {
+	if len(commit) > 12 {
+		return commit[:12]
+	}
+	return commit
+}

internal/builder/check_merge_test.go

@@ -0,0 +1,212 @@
+package builder
+
+import (
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+// **A merge check judges the merge, not the head** (novox/hq ADR 0323, issue 341): the head merged into the trunk
+// commit in the check's own clone, never pushed; a head that does not merge cleanly fails, naming the files; the
+// verdict names the head, the trunk commit and the commits of the repositories read beside it.
+
+// aTrunkAndABranch is a repository whose main moved after the branch was cut: main holds trunkFiles over the
+// common files, the branch headFiles. It answers the repository, the branch's head and main's head.
+func aTrunkAndABranch(t *testing.T, common, trunkFiles, headFiles map[string]string) (string, string, string) {
+	t.Helper()
+	dir := t.TempDir()
+	git := func(args ...string) string {
+		t.Helper()
+		cmd := exec.Command("git", args...)
+		cmd.Dir = dir
+		cmd.Env = append(os.Environ(), "GIT_AUTHOR_NAME=t", "GIT_AUTHOR_EMAIL=t@example.org",
+			"GIT_COMMITTER_NAME=t", "GIT_COMMITTER_EMAIL=t@example.org")
+		out, err := cmd.CombinedOutput()
+		if err != nil {
+			t.Fatalf("git %v: %v\n%s", args, err, out)
+		}
+		return strings.TrimSpace(string(out))
+	}
+	write := func(files map[string]string) {
+		for name, body := range files {
+			if err := os.MkdirAll(filepath.Dir(filepath.Join(dir, name)), 0o755); err != nil {
+				t.Fatal(err)
+			}
+			if err := os.WriteFile(filepath.Join(dir, name), []byte(body), 0o755); err != nil {
+				t.Fatal(err)
+			}
+		}
+		git("add", "-A")
+	}
+	git("init", "--quiet", "-b", "main")
+	write(common)
+	git("commit", "--quiet", "-m", "common")
+	git("checkout", "--quiet", "-b", "change")
+	write(headFiles)
+	git("commit", "--quiet", "-m", "the change")
+	head := git("rev-parse", "HEAD")
+	git("checkout", "--quiet", "main")
+	write(trunkFiles)
+	git("commit", "--quiet", "-m", "the trunk moved")
+	return dir, head, git("rev-parse", "HEAD")
+}
+
+func TestACheckJudgesTheHeadMergedIntoTheTrunk(t *testing.T) {
+	// main's script passes only in a tree holding both the trunk's file and the head's: the merge.
+	repo, head, trunk := aTrunkAndABranch(t,
+		map[string]string{CheckScript: "test -f trunk-only && test -f head-only || { echo 'FAIL: not the merge'; exit 1; }\n"},
+		map[string]string{"trunk-only": "t"}, map[string]string{"head-only": "h"})
+	beside, besideHead := aCheckedRepository(t, map[string]string{"README": "the catalogue"})
+	registry := aFactsRegistry(t)
+	aRuntimeOnThisMachine(t)
+
+	v, err := Check(t.Context(), Command, CheckSpec{ID: "check-341", Repository: repo, Ref: head, Owner: "novox",
+		Repo: "mesh-lab", Number: 1, Base: "main", Toolchain: "golang",
+		Beside: map[string]Beside{"mesh-catalog": {Repository: beside, Ref: besideHead}}}, t.TempDir(), registry,
+		GitCredential{}, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if v.Repo == nil || v.Repo.Verdict != "pass" {
+		t.Fatalf("the check did not judge the head merged into the trunk: %+v\n%s", v.Repo, v.Report)
+	}
+	if v.Head != head[:12] || v.Trunk != trunk[:12] {
+		t.Fatalf("the verdict names head %q and trunk %q, not %s and %s", v.Head, v.Trunk, head[:12], trunk[:12])
+	}
+	if v.Beside["mesh-catalog"] != besideHead[:12] {
+		t.Fatalf("the verdict names the catalogue read beside it as %q, not %s: %v", v.Beside["mesh-catalog"],
+			besideHead[:12], v.Beside)
+	}
+	if v.Merge == "" || v.Merge == head || v.Merge == trunk {
+		t.Fatalf("no merge of the head into the trunk was made for the check: %q", v.Merge)
+	}
+}
+
+func TestAHeadThatDoesNotMergeCleanlyFailsNamingTheFiles(t *testing.T) {
+	repo, head, trunk := aTrunkAndABranch(t,
+		map[string]string{"store.go": "package store\n\nconst Declared = 1\n", "other.go": "package store\n"},
+		map[string]string{"store.go": "package store\n\nconst Declared = 2\n"},
+		map[string]string{"store.go": "package store\n\nconst Declared = 3\n"})
+
+	// No artifact store and no container runtime: a head that does not merge is judged before either is needed.
+	v, err := Check(t.Context(), Command, CheckSpec{ID: "check-341-conflict", Repository: repo, Ref: head,
+		Owner: "novox", Repo: "mesh-lab", Number: 2, Base: "main", Toolchain: "golang"}, t.TempDir(), "",
+		GitCredential{}, nil)
+	if err != nil {
+		t.Fatalf("a head that does not merge cleanly was not judged: %v", err)
+	}
+	want := "does not merge cleanly into trunk " + trunk[:12]
+	for name, l := range map[string]*Layer{"gate": v.Gate, "repository": v.Repo} {
+		if l == nil || l.Verdict != "fail" || !strings.Contains(l.Summary, want) || !strings.Contains(l.Summary, "store.go") {
+			t.Fatalf("its %s layer said %+v, not a failure saying %q and naming store.go", name, l, want)
+		}
+	}
+	if strings.Contains(v.Summary, "other.go") {
+		t.Fatalf("a file not in conflict is named: %s", v.Summary)
+	}
+	if v.Head != head[:12] || v.Trunk != trunk[:12] {
+		t.Fatalf("the failure names head %q and trunk %q", v.Head, v.Trunk)
+	}
+}
+
+// **The merge made for a check is only checked** (ADR 0323 §2): the forge never receives it.
+func TestTheMergeMadeForACheckIsNeverPushed(t *testing.T) {
+	repo, head, trunk := aTrunkAndABranch(t, map[string]string{CheckScript: "true\n"},
+		map[string]string{"trunk-only": "t"}, map[string]string{"head-only": "h"})
+	registry := aFactsRegistry(t)
+	aRuntimeOnThisMachine(t)
+	refsBefore := gitOut(t, repo, "for-each-ref")
+
+	v, err := Check(t.Context(), Command, CheckSpec{ID: "check-341-push", Repository: repo, Ref: head, Owner: "novox",
+		Repo: "mesh-lab", Number: 3, Base: "main", Toolchain: "golang"}, t.TempDir(), registry, GitCredential{}, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if v.Merge == "" {
+		t.Fatal("the check made no merge of the head into the trunk")
+	}
+	if err := exec.Command("git", "-C", repo, "cat-file", "-e", v.Merge+"^{commit}").Run(); err == nil {
+		t.Fatalf("the merge %s made for the check reached the forge's repository", v.Merge)
+	}
+	if after := gitOut(t, repo, "for-each-ref"); after != refsBefore {
+		t.Fatalf("the check moved a ref of the forge's repository:\nbefore %s\nafter %s", refsBefore, after)
+	}
+	if got := gitOut(t, repo, "rev-parse", "main"); got != trunk {
+		t.Fatalf("the trunk moved to %s", got)
+	}
+}
+
+// A delivery group's composed check merges each member's head into its own trunk's head (ADR 0323 §6), and names
+// both for each; a member that does not merge cleanly fails the composed check, naming it.
+func TestAGroupsComposedCheckMergesEachMemberIntoItsTrunk(t *testing.T) {
+	repo, head, trunk := aTrunkAndABranch(t, map[string]string{CheckScript: "true\n"},
+		map[string]string{"trunk-only": "t"}, map[string]string{"head-only": "h"})
+	member, memberHead, memberTrunk := aTrunkAndABranch(t, map[string]string{"a": "1"},
+		map[string]string{"b": "trunk"}, map[string]string{"c": "head"})
+	registry := aFactsRegistry(t)
+	aRuntimeOnThisMachine(t)
+
+	v, err := Check(t.Context(), Command, CheckSpec{ID: "check-341-group", Repository: repo, Ref: head, Owner: "novox",
+		Repo: "mesh-controller", Number: 4, Base: "main", Toolchain: "golang", Group: []GroupHead{{Owner: "novox",
+			Repo: "mesh-host", Repository: member, Ref: memberHead, Base: "main"}}}, t.TempDir(), registry,
+		GitCredential{}, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if v.Head != head[:12] || v.Trunk != trunk[:12] {
+		t.Fatalf("the composed check names its first head %q into %q", v.Head, v.Trunk)
+	}
+	if len(v.Members) != 1 || v.Members[0].Head != memberHead[:12] || v.Members[0].Trunk != memberTrunk[:12] {
+		t.Fatalf("the composed check names its members %+v, not mesh-host %s into %s", v.Members, memberHead[:12],
+			memberTrunk[:12])
+	}
+
+	conflicting, conflictHead, _ := aTrunkAndABranch(t, map[string]string{"a": "1"}, map[string]string{"a": "2"},
+		map[string]string{"a": "3"})
+	v, err = Check(t.Context(), Command, CheckSpec{ID: "check-341-group-conflict", Repository: repo, Ref: head,
+		Owner: "novox", Repo: "mesh-controller", Number: 4, Base: "main", Toolchain: "golang", Group: []GroupHead{{
+			Owner: "novox", Repo: "mesh-host", Repository: conflicting, Ref: conflictHead, Base: "main"}}}, t.TempDir(),
+		registry, GitCredential{}, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if v.Verdict != "fail" || !strings.Contains(v.Summary, "novox/mesh-host") ||
+		!strings.Contains(v.Summary, "does not merge cleanly") {
+		t.Fatalf("a member that does not merge cleanly was answered %s: %s", v.Verdict, v.Summary)
+	}
+}
+
+func gitOut(t *testing.T, dir string, args ...string) string {
+	t.Helper()
+	out, err := exec.Command("git", append([]string{"-C", dir}, args...)...).CombinedOutput()
+	if err != nil {
+		t.Fatalf("git %v: %v\n%s", args, err, out)
+	}
+	return strings.TrimSpace(string(out))
+}
+
+// No hook runs when a check makes its merge: not one in the clone, whatever the build machine's git configuration says.
+func TestACheckMergeRunsNoHook(t *testing.T) {
+	repo, head, _ := aTrunkAndABranch(t, map[string]string{"a": "1"}, map[string]string{"b": "trunk"},
+		map[string]string{"c": "head"})
+	clone := filepath.Join(t.TempDir(), "clone")
+	if out, err := exec.Command("git", "clone", "--quiet", repo, clone).CombinedOutput(); err != nil {
+		t.Fatalf("%v\n%s", err, out)
+	}
+	ran := filepath.Join(t.TempDir(), "ran")
+	for _, hook := range []string{"pre-merge-commit", "commit-msg", "prepare-commit-msg", "post-merge"} {
+		if err := os.WriteFile(filepath.Join(clone, ".git", "hooks", hook),
+			[]byte("#!/bin/sh\necho "+hook+" >> "+ran+"\n"), 0o755); err != nil {
+			t.Fatal(err)
+		}
+	}
+	m, err := mergeIntoTrunk(t.Context(), Command, clone, "main", head)
+	if err != nil || m.Merge == "" {
+		t.Fatalf("the merge was not made: %+v, %v", m, err)
+	}
+	if said, err := os.ReadFile(ran); err == nil {
+		t.Fatalf("a hook ran when the check made its merge: %s", said)
+	}
+}

internal/builder/replay341_test.go

@@ -0,0 +1,139 @@
+package builder
+
+import (
+	"net"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+// TestReplay341 is the replay of novox/hq issue 341, written with only what the build agent had before its fix,
+// so mesh-lab's prover can lay it over the commit before. On 2026-10-09 node-engine #64/#65 merged at 00:15 and
+// added Applied.Declared, under the JSON key `declared`, to the store record. #66, checked at 00:49 at its head,
+// had added its own Applied.Declared under the same key on other lines. Its check passed; git merged the two
+// edits without a conflict, and the trunk no longer compiled: "Declared redeclared". Before the fix the check
+// judged the head alone and passed. After it (novox/hq ADR 0323), the check judges the head merged into the
+// trunk commit that held the other field, and fails saying the trunk does not compile.
+//
+// It runs the check whole, with a container runtime that runs each container's command on this machine
+// (aRuntimeOnThisMachine): the repository's own check is `go build ./...`.
+func TestReplay341(t *testing.T) {
+	origin, head := theNinthOfOctober(t)
+	registry := aFactsRegistry(t)
+	aRuntimeOnThisMachine(t)
+
+	v, err := Check(t.Context(), Command, CheckSpec{ID: "replay-341", Repository: origin, Ref: head, Owner: "novox",
+		Repo: "mesh-host", Number: 66, Base: "main", Toolchain: "golang"}, t.TempDir(), registry, GitCredential{}, nil)
+	if err != nil {
+		t.Fatalf("the check could not run: %v", err)
+	}
+	if v.Repo == nil || v.Repo.Verdict != "fail" {
+		t.Fatalf("node-engine #66 at its head was answered %+v: the merge it makes into the trunk that holds #65's "+
+			"field does not compile, and the check let it merge", v.Repo)
+	}
+	if said := v.Repo.Summary + "\n" + v.Repo.Failed + "\n" + v.Report; !strings.Contains(said, "Declared redeclared") {
+		t.Fatalf("the check failed without saying the trunk does not compile:\n%s", said)
+	}
+}
+
+// theNinthOfOctober is the node-engine's repository as it stood at 00:49 on 2026-10-09, in miniature: a trunk
+// holding #65's Applied.Declared (a string, key `declared`), and #66's head, branched before it, holding its own
+// Applied.Declared (a *FoundUnit, the same key) on other lines. Each compiles alone; their merge does not.
+func theNinthOfOctober(t *testing.T) (string, string) {
+	t.Helper()
+	origin := t.TempDir()
+	git := func(args ...string) string {
+		t.Helper()
+		cmd := exec.Command("git", args...)
+		cmd.Dir = origin
+		cmd.Env = append(os.Environ(), "GIT_AUTHOR_NAME=t", "GIT_AUTHOR_EMAIL=t@example.org",
+			"GIT_COMMITTER_NAME=t", "GIT_COMMITTER_EMAIL=t@example.org")
+		out, err := cmd.CombinedOutput()
+		if err != nil {
+			t.Fatalf("git %v: %v\n%s", args, err, out)
+		}
+		return strings.TrimSpace(string(out))
+	}
+	write := func(name, body string) {
+		t.Helper()
+		if err := os.MkdirAll(filepath.Dir(filepath.Join(origin, name)), 0o755); err != nil {
+			t.Fatal(err)
+		}
+		if err := os.WriteFile(filepath.Join(origin, name), []byte(body), 0o755); err != nil {
+			t.Fatal(err)
+		}
+	}
+	store := func(declared65, declared66 string) string {
+		return "package store\n\n// FoundUnit is a unit found on the machine.\ntype FoundUnit struct{ Name string }\n\n" +
+			"// Applied is what the node-engine applied.\ntype Applied struct {\n\tGeneration int `json:\"generation\"`\n" +
+			declared66 + "\tModules []string `json:\"modules\"`\n\tFiles []string `json:\"files\"`\n" +
+			"\tUnits []string `json:\"units\"`\n\tAt string `json:\"at\"`\n" + declared65 + "}\n"
+	}
+	git("init", "--quiet", "-b", "main")
+	write("go.mod", "module example.org/mesh-host\n\ngo 1.21\n")
+	write("internal/store/store.go", store("", ""))
+	write(CheckScript, "# mesh-check-toolchain: go\nset -e\nGOFLAGS= GOWORK=off GOTOOLCHAIN=local GOPROXY=off go build ./...\n")
+	git("add", "-A")
+	git("commit", "--quiet", "-m", "#63: the store record")
+	git("checkout", "--quiet", "-b", "adr-0269")
+	write("internal/store/store.go", store("", "\tDeclared *FoundUnit `json:\"declared\"`\n"))
+	git("commit", "--quiet", "-am", "#66: the unit a declaration names")
+	head := git("rev-parse", "HEAD")
+	git("checkout", "--quiet", "main")
+	write("internal/store/store.go", store("\tDeclared string `json:\"declared\"`\n", ""))
+	git("commit", "--quiet", "-am", "#65: the declaration applied")
+	return origin, head
+}
+
+// aRuntimeOnThisMachine puts a container runtime on PATH that runs a container's command on this machine, in the
+// directory and with the environment the check gives it: a store and a bus that answer, a judge that is never
+// built, and the repository's own check run as written. Only for a check whose code is the test's own.
+func aRuntimeOnThisMachine(t *testing.T) {
+	t.Helper()
+	bus, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { bus.Close() })
+	go func() {
+		for {
+			c, err := bus.Accept()
+			if err != nil {
+				return
+			}
+			c.Close()
+		}
+	}()
+	dir := t.TempDir()
+	runtime := `#!/bin/sh
+cmd="$1"; shift
+case "$cmd" in
+ps|rm|exec) exit 0 ;;
+port) echo "` + bus.Addr().String() + `"; exit 0 ;;
+run)
+  workdir=""; detached=""
+  while [ $# -gt 0 ]; do
+    case "$1" in
+      -d) detached=1; shift ;;
+      --rm) shift ;;
+      --workdir) workdir="$2"; shift 2 ;;
+      --env) export "$2"; shift 2 ;;
+      --network|--volume|--user|--label|--name|-p|-e) shift 2 ;;
+      *) break ;;
+    esac
+  done
+  if [ -n "$detached" ]; then echo replay-container; exit 0; fi
+  shift
+  if [ "$1" = "sh" ] && [ -n "$workdir" ]; then cd "$workdir" && exec "$@"; fi
+  echo "no such image on this machine" >&2
+  exit 1 ;;
+esac
+exit 1
+`
+	if err := os.WriteFile(filepath.Join(dir, "docker"), []byte(runtime), 0o755); err != nil {
+		t.Fatal(err)
+	}
+	t.Setenv("PATH", dir+string(os.PathListSeparator)+os.Getenv("PATH"))
+}

internal/builder/upstream_file.go

@@ -0,0 +1,305 @@
+package builder
+
+import (
+	"archive/tar"
+	"bufio"
+	"bytes"
+	"compress/bzip2"
+	"compress/gzip"
+	"context"
+	"crypto/sha256"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/therootcompany/xz"
+)
+
+// An archive whose source is somebody else's published file, pinned by URL and sha256 (novox/hq ADR 0316
+// §2, §6, to-be 56 §7): a mail client's release, an add-on's xpi.
+//
+// **Fetched by the build seat, checked against the pin before anything is read from it, and packed as any
+// archive is packed.** What a machine receives is the mesh's own archive from the artifact store, by digest,
+// exactly as for a directory of the repository; no machine ever asks the vendor. A file whose bytes are not
+// the pin's fails the build and names both digests, because the address serving something else is the one
+// thing the pin exists to catch.
+//
+// **Kept in the build seat's workspace under its sha256**, so it is fetched once: a vendor that serves only
+// its newest version at one address (Owl) would otherwise break every later build of the same pin.
+
+// maxUpstream is the largest upstream file fetched, and the largest a release may unpack to: the node-engine
+// unpacks no archive larger than this either (mesh-host internal/apply/archive.go, maxArchive).
+const maxUpstream = 512 << 20
+
+// maxEntries is the most entries an upstream archive may hold: millions of empty ones would fill the build
+// seat's inodes and the node's. Betterbird's release holds 64.
+const maxEntries = 100_000
+
+// noDowngrade refuses a redirect off https: the digest still guards the bytes, and a fetch in the clear says
+// to whoever is on the path what the build seat fetches.
+func noDowngrade(req *http.Request, via []*http.Request) error {
+	if req.URL.Scheme != "https" {
+		return fmt.Errorf("%s redirected to %s, which is not https", via[0].URL, req.URL)
+	}
+	if len(via) >= 10 {
+		return errors.New("more than 10 redirects")
+	}
+	return nil
+}
+
+// upstreamClient fetches upstream files: a variable so a test serves its own.
+var upstreamClient = &http.Client{Timeout: 15 * time.Minute}
+
+// upstreamDir is where the build seat keeps the upstream files it fetched, by sha256.
+func upstreamDir(workspace string) string { return filepath.Join(workspace, "upstream") }
+
+// upstreamArchive is the packed archive of an artifact pinned by URL: the file fetched (or kept from an
+// earlier build) and checked, then laid out as the artifact says and packed.
+func upstreamArchive(ctx context.Context, workspace string, a catalogue.Artifact,
+	say func(step, format string, args ...any)) ([]byte, error) {
+	file, err := upstreamFile(ctx, workspace, a, say)
+	if err != nil {
+		return nil, err
+	}
+	laid := filepath.Join(workspace, "upstream-"+a.Name)
+	if err := os.RemoveAll(laid); err != nil {
+		return nil, err
+	}
+	defer os.RemoveAll(laid)
+	if err := os.MkdirAll(laid, 0o755); err != nil {
+		return nil, err
+	}
+	if a.File != "" {
+		body, err := os.ReadFile(file)
+		if err != nil {
+			return nil, err
+		}
+		if err := os.WriteFile(filepath.Join(laid, a.File), body, 0o644); err != nil {
+			return nil, err
+		}
+	} else if err := unpackUpstream(ctx, file, laid, a.Within); err != nil {
+		return nil, fmt.Errorf("%s (%s): %w", a.URL, a.Version, err)
+	}
+	return pack(laid)
+}
+
+// upstreamFile is the path of the pinned file in the workspace: kept from an earlier build when its bytes
+// are still the pin's, else fetched now and kept only when they are.
+func upstreamFile(ctx context.Context, workspace string, a catalogue.Artifact,
+	say func(step, format string, args ...any)) (string, error) {
+	want := strings.ToLower(a.SHA256)
+	dir := upstreamDir(workspace)
+	kept := filepath.Join(dir, want)
+	if got, err := sumOf(kept); err == nil {
+		if got == want {
+			say("upstream", "%s %s: kept from an earlier build (sha256:%s)", a.Name, a.Version, short(want))
+			return kept, nil
+		}
+		// Changed on disk since it was kept: fetched again rather than trusted.
+		os.Remove(kept)
+	}
+	if err := os.MkdirAll(dir, 0o755); err != nil {
+		return "", err
+	}
+	say("upstream", "fetching %s (%s)", a.URL, a.Version)
+	request, err := http.NewRequestWithContext(ctx, http.MethodGet, a.URL, nil)
+	if err != nil {
+		return "", err
+	}
+	client := *upstreamClient
+	client.CheckRedirect = noDowngrade
+	response, err := client.Do(request)
+	if err != nil {
+		return "", fmt.Errorf("cannot fetch %s: %w", a.URL, err)
+	}
+	defer response.Body.Close()
+	if response.StatusCode != http.StatusOK {
+		return "", fmt.Errorf("%s answered %s", a.URL, response.Status)
+	}
+	part, err := os.CreateTemp(dir, want+".*.part")
+	if err != nil {
+		return "", err
+	}
+	defer os.Remove(part.Name())
+	hash := sha256.New()
+	n, err := io.Copy(io.MultiWriter(part, hash), io.LimitReader(response.Body, maxUpstream+1))
+	if cerr := part.Close(); err == nil {
+		err = cerr
+	}
+	if err != nil {
+		return "", fmt.Errorf("fetching %s: %w", a.URL, err)
+	}
+	if n > maxUpstream {
+		return "", fmt.Errorf("%s is larger than %d bytes, more than a machine unpacks; nothing was kept", a.URL, maxUpstream)
+	}
+	got := hex.EncodeToString(hash.Sum(nil))
+	if got != want {
+		return "", fmt.Errorf("%s was pinned as sha256:%s and what it served is sha256:%s (%d bytes); nothing "+
+			"was kept. The address serves another file than the one reviewed: compare it, then move the pin "+
+			"in a reviewed change (novox/hq ADR 0316)", a.URL, want, got, n)
+	}
+	if err := os.Rename(part.Name(), kept); err != nil {
+		return "", err
+	}
+	say("upstream", "%s %s: %d bytes, sha256:%s as pinned", a.Name, a.Version, n, short(want))
+	return kept, nil
+}
+
+// sumOf is the sha256 of a file, in hexadecimal.
+func sumOf(file string) (string, error) {
+	f, err := os.Open(file)
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+	hash := sha256.New()
+	if _, err := io.Copy(hash, f); err != nil {
+		return "", err
+	}
+	return hex.EncodeToString(hash.Sum(nil)), nil
+}
+
+// unpackUpstream unpacks a tar archive, compressed with gzip, bzip2 or xz (told by its first bytes), into a
+// directory: of its entries only those within `within` (all, when empty), with that prefix taken off.
+//
+// **Only files and directories, and nothing outside.** A link, a device or an entry naming a path outside
+// the archive, or outside `within`, refuses the build by name: the node-engine unpacks only files and
+// directories, and an archive quietly unpacked without what it held would be a release that is not the one
+// pinned.
+func unpackUpstream(ctx context.Context, file, into, within string) error {
+	f, err := os.Open(file)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	buffered := bufio.NewReader(f)
+	magic, _ := buffered.Peek(6)
+	var stream io.Reader
+	switch {
+	case bytes.HasPrefix(magic, []byte{0x1f, 0x8b}):
+		zipped, err := gzip.NewReader(buffered)
+		if err != nil {
+			return err
+		}
+		defer zipped.Close()
+		stream = zipped
+	case bytes.HasPrefix(magic, []byte("BZh")):
+		stream = bzip2.NewReader(buffered)
+	case bytes.HasPrefix(magic, []byte{0xfd, '7', 'z', 'X', 'Z', 0x00}):
+		// Read in Go (github.com/therootcompany/xz, a port of xz-embedded), never by a tool the build seat's image
+		// may not carry: the seat's image is the catalogue's build-agent recipe, which installs git and docker-cli
+		// alone, and a release pinned as .tar.xz failed there on 2026-10-12 (hq issue 345). xzDictMax is a real
+		// maximum: a block whose LZMA2 dictionary is larger is refused before its dictionary is allocated
+		// (ErrMemlimit). The reader keeps a filter decoder for every block of a stream, so the file's framing is
+		// walked first and a file of more blocks than xzBlocksMax is refused before anything is decoded
+		// (xz_framing.go). What the stream unpacks to is bounded by untar (maxUpstream, maxEntries).
+		if err := xzWithinLimits(file); err != nil {
+			return err
+		}
+		zipped, err := xz.NewReader(buffered, xzDictMax)
+		if err != nil {
+			return fmt.Errorf("it is not an xz stream this build seat reads (a dictionary of %d MiB at most): %v",
+				xzDictMax>>20, err)
+		}
+		stream = zipped
+	default:
+		return errors.New("it is not a tar archive compressed with gzip, bzip2 or xz; a single file is kept " +
+			"whole by naming it in `file`")
+	}
+	return untar(stream, into, within)
+}
+
+// xzDictMax is the largest xz dictionary read: xz's own presets use at most 64 MiB (-9); a stream asking for
+// more is refused rather than given the memory.
+const xzDictMax = 64 << 20
+
+// untar writes a tar stream's files and directories within `within` into a directory.
+func untar(stream io.Reader, into, within string) error {
+	reader := tar.NewReader(stream)
+	prefix := ""
+	if within != "" {
+		prefix = path.Clean(within) + "/"
+	}
+	var total int64
+	files, entries := 0, 0
+	for {
+		header, err := reader.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return err
+		}
+		if entries++; entries > maxEntries {
+			return fmt.Errorf("it holds more than %d entries", maxEntries)
+		}
+		if header.Typeflag == tar.TypeXGlobalHeader {
+			// A pax global header (git archive writes one) names no file.
+			continue
+		}
+		name := path.Clean(strings.TrimPrefix(header.Name, "./"))
+		if path.IsAbs(name) || name == ".." || strings.HasPrefix(name, "../") {
+			return fmt.Errorf("%s names a path outside the archive", header.Name)
+		}
+		if name == "." || name+"/" == prefix ||
+			(header.Typeflag == tar.TypeDir && strings.HasPrefix(prefix, name+"/")) {
+			// The archive's root, the directory taken, or one of its parents.
+			continue
+		}
+		if prefix != "" {
+			if !strings.HasPrefix(name, prefix) {
+				return fmt.Errorf("%s is outside %s, the directory the artifact is taken from", header.Name, within)
+			}
+			name = strings.TrimPrefix(name, prefix)
+		}
+		target := filepath.Join(into, filepath.FromSlash(name))
+		switch header.Typeflag {
+		case tar.TypeDir:
+			if err := os.MkdirAll(target, 0o755); err != nil {
+				return err
+			}
+		case tar.TypeReg:
+			total += header.Size
+			if total > maxUpstream {
+				return fmt.Errorf("it unpacks to more than %d bytes, more than a machine unpacks", maxUpstream)
+			}
+			if err := os.MkdirAll(filepath.Dir(target), 0o755); err != nil {
+				return err
+			}
+			mode := os.FileMode(0o644)
+			if header.Mode&0o111 != 0 {
+				mode = 0o755
+			}
+			out, err := os.OpenFile(target, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, mode)
+			if err != nil {
+				return err
+			}
+			if _, err := io.Copy(out, io.LimitReader(reader, header.Size)); err != nil {
+				out.Close()
+				return err
+			}
+			if err := out.Close(); err != nil {
+				return err
+			}
+			files++
+		default:
+			return fmt.Errorf("%s is a %c, and an archive carries only files and directories", header.Name,
+				header.Typeflag)
+		}
+	}
+	if files == 0 {
+		if within != "" {
+			return fmt.Errorf("it holds no file within %s", within)
+		}
+		return errors.New("it holds no file")
+	}
+	return nil
+}

internal/builder/upstream_file_test.go

@@ -0,0 +1,469 @@
+package builder
+
+import (
+	"archive/tar"
+	"bytes"
+	"compress/gzip"
+	"context"
+	"crypto/sha256"
+	"encoding/binary"
+	"encoding/hex"
+	"fmt"
+	"hash/crc32"
+	"io"
+	"net"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"sort"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+)
+
+// An archive pinned by URL and sha256 (novox/hq ADR 0316 §2, §6; How it is checked: "an upstream artifact
+// whose download does not match its sha256 fails the build and names both digests").
+
+type tarEntry struct {
+	name, body string
+	mode       int64
+	kind       byte
+}
+
+func tarOf(t *testing.T, entries []tarEntry) []byte {
+	t.Helper()
+	var raw bytes.Buffer
+	w := tar.NewWriter(&raw)
+	for _, e := range entries {
+		kind := e.kind
+		if kind == 0 {
+			kind = tar.TypeReg
+		}
+		h := &tar.Header{Name: e.name, Mode: e.mode, Typeflag: kind, Size: int64(len(e.body))}
+		if kind == tar.TypeSymlink {
+			h.Linkname, h.Size = "/usr/share/hunspell", 0
+		}
+		if kind == tar.TypeDir {
+			h.Size = 0
+		}
+		if err := w.WriteHeader(h); err != nil {
+			t.Fatal(err)
+		}
+		if kind == tar.TypeReg {
+			if _, err := w.Write([]byte(e.body)); err != nil {
+				t.Fatal(err)
+			}
+		}
+	}
+	if err := w.Close(); err != nil {
+		t.Fatal(err)
+	}
+	return raw.Bytes()
+}
+
+func gzipped(t *testing.T, body []byte) []byte {
+	t.Helper()
+	var out bytes.Buffer
+	z := gzip.NewWriter(&out)
+	if _, err := z.Write(body); err != nil {
+		t.Fatal(err)
+	}
+	if err := z.Close(); err != nil {
+		t.Fatal(err)
+	}
+	return out.Bytes()
+}
+
+func sumHex(b []byte) string {
+	s := sha256.Sum256(b)
+	return hex.EncodeToString(s[:])
+}
+
+// vendor serves files by path over https and counts what it was asked.
+type vendor struct {
+	files map[string][]byte
+	asked int
+}
+
+func serveVendor(t *testing.T, v *vendor) string {
+	t.Helper()
+	server := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		v.asked++
+		body, ok := v.files[r.URL.Path]
+		if !ok {
+			http.NotFound(w, r)
+			return
+		}
+		w.Write(body)
+	}))
+	t.Cleanup(server.Close)
+	before := upstreamClient
+	// Under a public name, as a manifest must say it: example.com, which the test server's certificate
+	// names, dialled at the server.
+	transport := server.Client().Transport.(*http.Transport).Clone()
+	addr := server.Listener.Addr().String()
+	transport.DialContext = func(ctx context.Context, network, _ string) (net.Conn, error) {
+		return (&net.Dialer{}).DialContext(ctx, network, addr)
+	}
+	upstreamClient = &http.Client{Transport: transport}
+	t.Cleanup(func() { upstreamClient = before })
+	return "https://example.com"
+}
+
+// entriesOf lists a packed archive: each file with its mode and content.
+func entriesOf(t *testing.T, packed []byte) map[string]string {
+	t.Helper()
+	z, err := gzip.NewReader(bytes.NewReader(packed))
+	if err != nil {
+		t.Fatal(err)
+	}
+	r := tar.NewReader(z)
+	out := map[string]string{}
+	for {
+		h, err := r.Next()
+		if err == io.EOF {
+			return out
+		}
+		if err != nil {
+			t.Fatal(err)
+		}
+		body, _ := io.ReadAll(r)
+		out[h.Name] = string(body) + " " + os.FileMode(h.Mode).String()
+	}
+}
+
+func release(t *testing.T) []byte {
+	return gzipped(t, tarOf(t, []tarEntry{
+		{name: "betterbird/", kind: tar.TypeDir, mode: 0o755},
+		{name: "betterbird/application.ini", body: "[App]\nVersion=153.4.0\n", mode: 0o644},
+		{name: "betterbird/betterbird", body: "#!/bin/sh\n", mode: 0o755},
+		{name: "betterbird/defaults/pref/channel-prefs.js", body: "pref(\"app.update.channel\", \"default\");\n", mode: 0o644},
+	}))
+}
+
+func pinnedManifest(base, sum string) string {
+	return `{"module":"betterbird","version":"1",
+  "build":{"artifacts":[
+    {"name":"archive","kind":"archive","url":"` + base + `/release.tar.gz","sha256":"` + sum + `","version":"153.4.0esr-bb10","within":"betterbird"}]},
+  "resources":[{"id":"installation","type":"archive","path":"/opt/betterbird","artifact":"archive"}]}`
+}
+
+func TestAnArchivePinnedByURLIsFetchedCheckedAndPackedWithoutItsOwnDirectory(t *testing.T) {
+	body := release(t)
+	v := &vendor{files: map[string][]byte{"/release.tar.gz": body}}
+	base := serveVendor(t, v)
+	r, workspace := aRepository(t, pinnedManifest(base, sumHex(body)), nil)
+	got, err := Build(context.Background(), r.run, r, "https://forge.invalid/catalogue.git", "", "", workspace, nil,
+		Npmrc{}, GitCredential{}, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	digest, _ := got.Manifest.Resources[0]["digest"].(string)
+	if !strings.HasPrefix(digest, "sha256:") || r.archives["betterbird/archive"] != digest {
+		t.Fatalf("the release was not published and pinned as the module's archive: %v, published %v",
+			got.Manifest.Resources[0], r.archives)
+	}
+
+	packed, err := upstreamArchive(context.Background(), workspace, catalogue.Artifact{Name: "archive", Kind: "archive",
+		URL: base + "/release.tar.gz", SHA256: sumHex(body), Version: "153.4.0esr-bb10", Within: "betterbird"},
+		func(string, string, ...any) {})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if "sha256:"+sumHex(packed) != digest {
+		t.Fatalf("a second packing of one pin gave another digest: %s and %s", digest, sumHex(packed))
+	}
+	entries := entriesOf(t, packed)
+	want := map[string]string{
+		"application.ini":                "[App]\nVersion=153.4.0\n -rw-r--r--",
+		"betterbird":                     "#!/bin/sh\n -rwxr-xr-x",
+		"defaults/pref/channel-prefs.js": "pref(\"app.update.channel\", \"default\");\n -rw-r--r--",
+	}
+	if len(entries) != len(want) {
+		t.Fatalf("the archive holds %v, want %v", entries, want)
+	}
+	for name, w := range want {
+		if entries[name] != w {
+			t.Errorf("%s is %q in the archive, want %q", name, entries[name], w)
+		}
+	}
+}
+
+func TestAnUpstreamFileIsFetchedOnceAndKeptByItsDigest(t *testing.T) {
+	// The vendor of an add-on serves only its newest version at one address: a pin that was fetched once
+	// must still build after the address moved on.
+	body := release(t)
+	v := &vendor{files: map[string][]byte{"/release.tar.gz": body}}
+	base := serveVendor(t, v)
+	r, workspace := aRepository(t, pinnedManifest(base, sumHex(body)), nil)
+	first, err := Build(context.Background(), r.run, r, "https://forge.invalid/catalogue.git", "", "", workspace, nil,
+		Npmrc{}, GitCredential{}, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	v.files["/release.tar.gz"] = []byte("the vendor's next release")
+	second, err := Build(context.Background(), r.run, r, "https://forge.invalid/catalogue.git", "", "", workspace, nil,
+		Npmrc{}, GitCredential{}, nil)
+	if err != nil {
+		t.Fatalf("a pin fetched before failed to build once the address served something else: %v", err)
+	}
+	if v.asked != 1 {
+		t.Fatalf("the vendor was asked %d times for one pin, want once", v.asked)
+	}
+	if first.Manifest.Resources[0]["digest"] != second.Manifest.Resources[0]["digest"] {
+		t.Fatal("two builds of one pin gave two digests")
+	}
+}
+
+func TestAnUpstreamFileWhoseDownloadDoesNotMatchItsPinFailsAndNamesBothDigests(t *testing.T) {
+	pinned := release(t)
+	served := gzipped(t, tarOf(t, []tarEntry{{name: "betterbird/betterbird", body: "not what was reviewed", mode: 0o755}}))
+	v := &vendor{files: map[string][]byte{"/release.tar.gz": served}}
+	base := serveVendor(t, v)
+	r, workspace := aRepository(t, pinnedManifest(base, sumHex(pinned)), nil)
+	_, err := Build(context.Background(), r.run, r, "https://forge.invalid/catalogue.git", "", "", workspace, nil,
+		Npmrc{}, GitCredential{}, nil)
+	if err == nil {
+		t.Fatal("a download that is not the pinned file was built")
+	}
+	for _, digest := range []string{sumHex(pinned), sumHex(served)} {
+		if !strings.Contains(err.Error(), "sha256:"+digest) {
+			t.Errorf("the refusal does not name sha256:%s: %v", digest, err)
+		}
+	}
+	if len(r.archives) != 0 {
+		t.Fatalf("something was published: %v", r.archives)
+	}
+	kept, _ := filepath.Glob(filepath.Join(upstreamDir(workspace), "*"))
+	if len(kept) != 0 {
+		t.Fatalf("the refused download was kept: %v", kept)
+	}
+}
+
+func TestAnUpstreamFileThatIsNotAnArchiveIsKeptWholeUnderItsName(t *testing.T) {
+	xpi := []byte("PK\x03\x04 an add-on")
+	v := &vendor{files: map[string][]byte{"/owl.xpi": xpi}}
+	base := serveVendor(t, v)
+	packed, err := upstreamArchive(context.Background(), t.TempDir(), catalogue.Artifact{Name: "owl", Kind: "archive",
+		URL: base + "/owl.xpi", SHA256: sumHex(xpi), Version: "1.5.6.1", File: "owl.xpi"}, func(string, string, ...any) {})
+	if err != nil {
+		t.Fatal(err)
+	}
+	entries := entriesOf(t, packed)
+	if len(entries) != 1 || entries["owl.xpi"] != string(xpi)+" -rw-r--r--" {
+		t.Fatalf("the add-on was not kept whole as owl.xpi: %v", entries)
+	}
+}
+
+func TestAnUpstreamArchiveHoldingALinkOrAnEntryOutsideItsDirectoryIsRefused(t *testing.T) {
+	cases := map[string][]tarEntry{
+		// The community package links the dictionaries; a release carrying a link is not one a machine unpacks.
+		"is a 2": {{name: "betterbird/betterbird", body: "x", mode: 0o755},
+			{name: "betterbird/dictionaries", kind: tar.TypeSymlink}},
+		"outside betterbird": {{name: "betterbird/betterbird", body: "x", mode: 0o755},
+			{name: "README", body: "x", mode: 0o644}},
+		"outside the archive": {{name: "../etc/passwd", body: "x", mode: 0o644}},
+		"no file within":      {{name: "betterbird/", kind: tar.TypeDir, mode: 0o755}},
+	}
+	for want, entries := range cases {
+		body := gzipped(t, tarOf(t, entries))
+		v := &vendor{files: map[string][]byte{"/r.tar.gz": body}}
+		base := serveVendor(t, v)
+		_, err := upstreamArchive(context.Background(), t.TempDir(), catalogue.Artifact{Name: "archive", Kind: "archive",
+			URL: base + "/r.tar.gz", SHA256: sumHex(body), Version: "1", Within: "betterbird"}, func(string, string, ...any) {})
+		if err == nil || !strings.Contains(err.Error(), want) {
+			t.Errorf("an archive whose entry is %q was not refused for it: %v", want, err)
+		}
+	}
+}
+
+func TestAnUpstreamArchiveCompressedWithXzIsRead(t *testing.T) {
+	// Betterbird publishes its Linux release as .tar.xz; the build seat's image carries xz for it.
+	if _, err := exec.LookPath("xz"); err != nil {
+		t.Skip("NOT TESTED here: no xz on this machine (the build seat's image carries it)")
+	}
+	plain := tarOf(t, []tarEntry{{name: "betterbird/betterbird", body: "#!/bin/sh\n", mode: 0o755}})
+	cmd := exec.Command("xz", "-zc")
+	cmd.Stdin = bytes.NewReader(plain)
+	compressed, err := cmd.Output()
+	if err != nil {
+		t.Fatal(err)
+	}
+	v := &vendor{files: map[string][]byte{"/r.tar.xz": compressed}}
+	base := serveVendor(t, v)
+	packed, err := upstreamArchive(context.Background(), t.TempDir(), catalogue.Artifact{Name: "archive", Kind: "archive",
+		URL: base + "/r.tar.xz", SHA256: sumHex(compressed), Version: "1", Within: "betterbird"}, func(string, string, ...any) {})
+	if err != nil {
+		t.Fatal(err)
+	}
+	var names []string
+	for n := range entriesOf(t, packed) {
+		names = append(names, n)
+	}
+	sort.Strings(names)
+	if strings.Join(names, ",") != "betterbird" {
+		t.Fatalf("the xz release unpacked to %v", names)
+	}
+}
+
+func TestAnUpstreamTarWithAGlobalHeaderNestedWithinAndTrailingDataIsRead(t *testing.T) {
+	// git archive writes a pax global header; a release may unpack under a/b with a/ listed first; xz may be
+	// followed by bytes after the tar's end, which must be read before xz is waited for.
+	var raw bytes.Buffer
+	w := tar.NewWriter(&raw)
+	w.WriteHeader(&tar.Header{Typeflag: tar.TypeXGlobalHeader, Name: "pax_global_header", PAXRecords: map[string]string{"comment": "abc"}})
+	w.WriteHeader(&tar.Header{Name: "a/", Typeflag: tar.TypeDir, Mode: 0o755})
+	w.WriteHeader(&tar.Header{Name: "a/b/", Typeflag: tar.TypeDir, Mode: 0o755})
+	w.WriteHeader(&tar.Header{Name: "a/b/f", Typeflag: tar.TypeReg, Mode: 0o644, Size: 1})
+	w.Write([]byte("x"))
+	w.Close()
+	body := gzipped(t, raw.Bytes())
+	v := &vendor{files: map[string][]byte{"/r.tar.gz": body}}
+	base := serveVendor(t, v)
+	packed, err := upstreamArchive(context.Background(), t.TempDir(), catalogue.Artifact{Name: "a", Kind: "archive",
+		URL: base + "/r.tar.gz", SHA256: sumHex(body), Version: "1", Within: "a/b"}, func(string, string, ...any) {})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if e := entriesOf(t, packed); len(e) != 1 || e["f"] == "" {
+		t.Fatalf("%v", e)
+	}
+	if _, err := exec.LookPath("xz"); err != nil {
+		t.Skip("NOT TESTED here: no xz")
+	}
+	// A megabyte after the tar's end: more than a pipe holds.
+	trailing := append(append([]byte{}, raw.Bytes()...), bytes.Repeat([]byte{0}, 1<<20)...)
+	cmd := exec.Command("xz", "-zc")
+	cmd.Stdin = bytes.NewReader(trailing)
+	compressed, err := cmd.Output()
+	if err != nil {
+		t.Fatal(err)
+	}
+	v.files["/r.tar.xz"] = compressed
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+	if _, err := upstreamArchive(ctx, t.TempDir(), catalogue.Artifact{Name: "a", Kind: "archive", URL: base + "/r.tar.xz",
+		SHA256: sumHex(compressed), Version: "1", Within: "a/b"}, func(string, string, ...any) {}); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestAnUpstreamArchiveWithTooManyEntriesIsRefused(t *testing.T) {
+	var raw bytes.Buffer
+	w := tar.NewWriter(&raw)
+	for i := 0; i <= maxEntries; i++ {
+		w.WriteHeader(&tar.Header{Name: fmt.Sprintf("d%d/", i), Typeflag: tar.TypeDir, Mode: 0o755})
+	}
+	w.Close()
+	body := gzipped(t, raw.Bytes())
+	v := &vendor{files: map[string][]byte{"/r.tar.gz": body}}
+	base := serveVendor(t, v)
+	_, err := upstreamArchive(context.Background(), t.TempDir(), catalogue.Artifact{Name: "a", Kind: "archive",
+		URL: base + "/r.tar.gz", SHA256: sumHex(body), Version: "1"}, func(string, string, ...any) {})
+	if err == nil || !strings.Contains(err.Error(), "entries") {
+		t.Fatalf("%v", err)
+	}
+}
+
+func TestARedirectOffHttpsIsNotFollowed(t *testing.T) {
+	plain := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { w.Write([]byte("x")) }))
+	t.Cleanup(plain.Close)
+	secure := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		http.Redirect(w, r, plain.URL+"/r", http.StatusFound)
+	}))
+	t.Cleanup(secure.Close)
+	before := upstreamClient
+	upstreamClient = secure.Client()
+	t.Cleanup(func() { upstreamClient = before })
+	_, err := upstreamFile(context.Background(), t.TempDir(), catalogue.Artifact{Name: "a", URL: secure.URL + "/r",
+		SHA256: sumHex([]byte("x")), Version: "1", File: "a"}, func(string, string, ...any) {})
+	if err == nil || !strings.Contains(err.Error(), "not https") {
+		t.Fatalf("%v", err)
+	}
+}
+
+func TestAnXzReleaseIsReadWithoutAnyXzToolOnTheBuildSeat(t *testing.T) {
+	// The build seat's image (the catalogue's build-agent recipe) carries git and docker-cli alone: Betterbird's
+	// .tar.xz failed there on 2026-10-12 with "this build seat has no xz to read it" (hq issue 345). It is
+	// read in Go, with nothing on PATH.
+	t.Setenv("PATH", "")
+	body, err := os.ReadFile(filepath.Join("testdata", "release.tar.xz"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	v := &vendor{files: map[string][]byte{"/r.tar.xz": body}}
+	base := serveVendor(t, v)
+	packed, err := upstreamArchive(context.Background(), t.TempDir(), catalogue.Artifact{Name: "archive", Kind: "archive",
+		URL: base + "/r.tar.xz", SHA256: sumHex(body), Version: "1", Within: "betterbird"}, func(string, string, ...any) {})
+	if err != nil {
+		t.Fatal(err)
+	}
+	e := entriesOf(t, packed)
+	if len(e) != 2 || e["betterbird"] != "#!/bin/sh\n -rwxr-xr-x" || e["defaults/p.js"] != "pref(\"a\", 1);\n -rw-r--r--" {
+		t.Fatalf("%v", e)
+	}
+}
+
+// withDictionary is an xz stream whose first block's LZMA2 dictionary property is props, its header's CRC32
+// recomputed: a stream asking for a dictionary of its own choosing.
+func withDictionary(t *testing.T, stream []byte, props byte) []byte {
+	t.Helper()
+	out := append([]byte{}, stream...)
+	const at = 12 // the stream header
+	size := (int(out[at]) + 1) * 4
+	header := out[at : at+size]
+	flags := header[1]
+	i := 2
+	readVarint := func() {
+		for header[i]&0x80 != 0 {
+			i++
+		}
+		i++
+	}
+	if flags&0x40 != 0 {
+		readVarint()
+	}
+	if flags&0x80 != 0 {
+		readVarint()
+	}
+	if header[i] != 0x21 || header[i+1] != 0x01 {
+		t.Fatalf("the fixture's first filter is not LZMA2: % x", header)
+	}
+	header[i+2] = props
+	binary.LittleEndian.PutUint32(header[size-4:], crc32.ChecksumIEEE(header[:size-4]))
+	return out
+}
+
+func TestAnXzStreamAskingForTooLargeADictionaryIsRefused(t *testing.T) {
+	body, err := os.ReadFile(filepath.Join("testdata", "release.tar.xz"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	// 1 GiB (props 36) and 4 GiB less one (props 40): over the 64 MiB maximum, refused before allocation.
+	for _, props := range []byte{36, 40} {
+		crafted := withDictionary(t, body, props)
+		v := &vendor{files: map[string][]byte{"/r.tar.xz": crafted}}
+		base := serveVendor(t, v)
+		var before, after runtime.MemStats
+		runtime.GC()
+		runtime.ReadMemStats(&before)
+		_, err := upstreamArchive(context.Background(), t.TempDir(), catalogue.Artifact{Name: "archive", Kind: "archive",
+			URL: base + "/r.tar.xz", SHA256: sumHex(crafted), Version: "1", Within: "betterbird"}, func(string, string, ...any) {})
+		runtime.ReadMemStats(&after)
+		if err == nil || !strings.Contains(err.Error(), "dictionary") {
+			t.Errorf("props %d: a dictionary over the maximum was not refused: %v", props, err)
+		}
+		if grew := after.TotalAlloc - before.TotalAlloc; grew > 256<<20 {
+			t.Errorf("props %d: %d bytes were allocated for a refused stream", props, grew)
+		}
+	}
+	// The fixture as it is (a small dictionary) still reads.
+	if crafted := withDictionary(t, body, 0); len(crafted) == 0 {
+		t.Fatal("no fixture")
+	}
+}

internal/builder/xz_framing.go

@@ -0,0 +1,290 @@
+package builder
+
+import (
+	"bufio"
+	"bytes"
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"hash/crc32"
+	"io"
+	"os"
+)
+
+// xzBlocksMax and xzStreamsMax are the most blocks and the most concatenated streams an xz file may hold for
+// the build seat to read it.
+//
+// **Why a block count is limited at all.** The xz reader (github.com/therootcompany/xz v1.0.1) keeps one
+// filter decoder for every block that names a delta or BCJ filter, and frees them only when a stream ends:
+// its block counters are reset per stream, not per block. A stream of many tiny blocks therefore grows the
+// heap with its length: an `xz --block-size=1 --delta` file of 6 MB kept about 67 MiB live, which comes to
+// about 5.6 GiB at the 512 MiB download cap (review 68 on mesh-controller pull request 264, hq issue 345).
+//
+// **Why 1,024.** At about 340 bytes of decoder a block, 1,024 blocks keep at most about 0.35 MiB live. A
+// real release is far below it: Betterbird's archive is 1 stream with 1 block, and multi-threaded xz cuts
+// blocks of three times the dictionary (24 MiB at the default preset), so even 512 MiB unpacked in blocks
+// of 512 KiB stays within it. Streams are limited to 16 because a release is one stream; the decoders are
+// reused from one stream to the next, so the stream limit only bounds the work of this walk.
+const (
+	xzBlocksMax  = 1024
+	xzStreamsMax = 16
+)
+
+// xzWithinLimits walks an xz file's framing, without decompressing anything, and refuses one holding more
+// blocks or streams than the build seat reads.
+//
+// **The framing, not the index.** Each stream's index at its end lists its blocks, but the reader compares
+// the index with the blocks only after it has decoded them all, so a file whose index lies would still be
+// decoded block by block. This walk follows the same framing the reader follows: stream header, each block
+// header, the block's LZMA2 chunks (each chunk header carries its own compressed size, so a chunk is skipped
+// without being decoded), its padding and check, then the index and the footer. It counts the blocks the
+// reader would decode, and it also refuses an index whose count of blocks is not the count walked.
+func xzWithinLimits(file string) error {
+	f, err := os.Open(file)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	_, _, err = xzFraming(bufio.NewReader(f))
+	if errors.Is(err, errXzTooManyBlocks) || errors.Is(err, errXzTooManyStreams) {
+		return err
+	}
+	if err != nil {
+		return fmt.Errorf("it is not an xz file this build seat reads: %v", err)
+	}
+	return nil
+}
+
+var (
+	errXzTooManyBlocks = fmt.Errorf("it holds more than %d xz blocks, the most this build seat reads: "+
+		"its xz reader keeps a filter decoder for every block (hq issue 345)", xzBlocksMax)
+	errXzTooManyStreams = fmt.Errorf("it holds more than %d concatenated xz streams, the most this build "+
+		"seat reads", xzStreamsMax)
+)
+
+// xzFraming counts the streams and blocks of an xz file, checking its framing as it goes. It stops with
+// errXzTooManyBlocks or errXzTooManyStreams at the first block or stream over the limit.
+func xzFraming(r *bufio.Reader) (streams, blocks int, err error) {
+	full := func(n int) ([]byte, error) {
+		b := make([]byte, n)
+		if _, err := io.ReadFull(r, b); err != nil {
+			if err == io.EOF {
+				err = io.ErrUnexpectedEOF
+			}
+			return nil, err
+		}
+		return b, nil
+	}
+	skip := func(n int) error {
+		if got, err := r.Discard(n); err != nil || got != n {
+			return io.ErrUnexpectedEOF
+		}
+		return nil
+	}
+	for {
+		header, err := full(12)
+		if err != nil {
+			return streams, blocks, fmt.Errorf("stream %d: header: %v", streams+1, err)
+		}
+		if !bytes.Equal(header[:6], []byte{0xfd, '7', 'z', 'X', 'Z', 0x00}) {
+			return streams, blocks, fmt.Errorf("stream %d: no xz stream header", streams+1)
+		}
+		if header[6] != 0 || header[7]&0xf0 != 0 ||
+			crc32.ChecksumIEEE(header[6:8]) != binary.LittleEndian.Uint32(header[8:12]) {
+			return streams, blocks, fmt.Errorf("stream %d: a corrupt stream header", streams+1)
+		}
+		if streams++; streams > xzStreamsMax {
+			return streams, blocks, errXzTooManyStreams
+		}
+		checkSize := 0
+		if check := int(header[7]); check != 0 {
+			checkSize = 4 << ((check - 1) / 3)
+		}
+		inStream := 0
+		for {
+			first, err := r.ReadByte()
+			if err != nil {
+				return streams, blocks, fmt.Errorf("stream %d: no index: %v", streams, io.ErrUnexpectedEOF)
+			}
+			if first == 0 {
+				break // the index indicator
+			}
+			rest, err := full(int(first)*4 + 3)
+			if err != nil {
+				return streams, blocks, fmt.Errorf("stream %d, block %d: header: %v", streams, inStream+1, err)
+			}
+			if err := xzBlockHeader(append([]byte{first}, rest...)); err != nil {
+				return streams, blocks, fmt.Errorf("stream %d, block %d: %v", streams, inStream+1, err)
+			}
+			inStream++
+			if blocks++; blocks > xzBlocksMax {
+				return streams, blocks, errXzTooManyBlocks
+			}
+			// The block's LZMA2 chunks, up to the end marker.
+			size := 0
+			for {
+				control, err := r.ReadByte()
+				if err != nil {
+					return streams, blocks, fmt.Errorf("stream %d, block %d: %v", streams, inStream, io.ErrUnexpectedEOF)
+				}
+				size++
+				if control == 0 {
+					break
+				}
+				switch {
+				case control == 1 || control == 2: // stored: a 16-bit size less one, then the bytes
+					b, err := full(2)
+					if err != nil {
+						return streams, blocks, err
+					}
+					n := int(binary.BigEndian.Uint16(b)) + 1
+					if err := skip(n); err != nil {
+						return streams, blocks, err
+					}
+					size += 2 + n
+				case control >= 0x80: // LZMA: unpacked and packed sizes, the properties byte on a reset
+					b, err := full(4)
+					if err != nil {
+						return streams, blocks, err
+					}
+					n := int(binary.BigEndian.Uint16(b[2:])) + 1
+					size += 4
+					if control >= 0xc0 {
+						if err := skip(1); err != nil {
+							return streams, blocks, err
+						}
+						size++
+					}
+					if err := skip(n); err != nil {
+						return streams, blocks, err
+					}
+					size += n
+				default:
+					return streams, blocks, fmt.Errorf("stream %d, block %d: an LZMA2 chunk of kind %#x",
+						streams, inStream, control)
+				}
+			}
+			if pad := (4 - size%4) % 4; pad > 0 {
+				b, err := full(pad)
+				if err != nil || !bytes.Equal(b, make([]byte, pad)) {
+					return streams, blocks, fmt.Errorf("stream %d, block %d: corrupt block padding", streams, inStream)
+				}
+			}
+			if err := skip(checkSize); err != nil {
+				return streams, blocks, err
+			}
+		}
+		// The index: its count of records, two numbers each, padding, CRC32.
+		used := 1
+		count, n, err := xzVLI(r)
+		if err != nil {
+			return streams, blocks, fmt.Errorf("stream %d: index: %v", streams, err)
+		}
+		used += n
+		if count != uint64(inStream) {
+			return streams, blocks, fmt.Errorf("stream %d: its index lists %d blocks, but it holds %d",
+				streams, count, inStream)
+		}
+		for i := 0; i < 2*inStream; i++ {
+			_, n, err := xzVLI(r)
+			if err != nil {
+				return streams, blocks, fmt.Errorf("stream %d: index: %v", streams, err)
+			}
+			used += n
+		}
+		if err := skip((4-used%4)%4 + 4); err != nil {
+			return streams, blocks, fmt.Errorf("stream %d: index: %v", streams, err)
+		}
+		footer, err := full(12)
+		if err != nil || footer[10] != 'Y' || footer[11] != 'Z' {
+			return streams, blocks, fmt.Errorf("stream %d: no stream footer", streams)
+		}
+		// Stream padding: zero bytes, a multiple of four, then the end or another stream.
+		zeros := 0
+		for {
+			b, err := r.ReadByte()
+			if err == io.EOF {
+				if zeros%4 != 0 {
+					return streams, blocks, errors.New("stream padding not a multiple of four bytes")
+				}
+				return streams, blocks, nil
+			}
+			if err != nil {
+				return streams, blocks, err
+			}
+			if b != 0 {
+				_ = r.UnreadByte()
+				break
+			}
+			zeros++
+		}
+		if zeros%4 != 0 {
+			return streams, blocks, errors.New("stream padding not a multiple of four bytes")
+		}
+	}
+}
+
+// xzBlockHeader checks one block header: its CRC32, its flags, and that its last filter is LZMA2, the only
+// one whose chunks this walk can skip (and the only last filter the reader decodes).
+func xzBlockHeader(h []byte) error {
+	size := len(h)
+	if crc32.ChecksumIEEE(h[:size-4]) != binary.LittleEndian.Uint32(h[size-4:]) {
+		return errors.New("a corrupt block header")
+	}
+	flags := h[1]
+	if flags&0x3c != 0 {
+		return errors.New("a block header with reserved flags")
+	}
+	body := bytes.NewReader(h[2 : size-4])
+	if flags&0x40 != 0 {
+		if _, _, err := xzVLI(body); err != nil {
+			return err
+		}
+	}
+	if flags&0x80 != 0 {
+		if _, _, err := xzVLI(body); err != nil {
+			return err
+		}
+	}
+	var last uint64
+	for i := 0; i <= int(flags&3); i++ {
+		id, _, err := xzVLI(body)
+		if err != nil {
+			return err
+		}
+		props, _, err := xzVLI(body)
+		if err != nil {
+			return err
+		}
+		if props > uint64(body.Len()) {
+			return errors.New("a corrupt block header")
+		}
+		if _, err := body.Seek(int64(props), io.SeekCurrent); err != nil {
+			return err
+		}
+		last = id
+	}
+	if last != 0x21 {
+		return fmt.Errorf("a block whose last filter is %#x, not LZMA2", last)
+	}
+	return nil
+}
+
+// xzVLI reads one of xz's variable-length integers (at most 9 bytes, 7 bits each), and how many bytes it took.
+func xzVLI(r io.ByteReader) (uint64, int, error) {
+	var v uint64
+	for i := 0; i < 9; i++ {
+		b, err := r.ReadByte()
+		if err != nil {
+			return 0, i, io.ErrUnexpectedEOF
+		}
+		v |= uint64(b&0x7f) << (7 * i)
+		if b&0x80 == 0 {
+			if i > 0 && b == 0 {
+				return 0, i + 1, errors.New("a number not in its shortest form")
+			}
+			return v, i + 1, nil
+		}
+	}
+	return 0, 9, errors.New("a number longer than nine bytes")
+}

internal/builder/xz_framing_test.go

@@ -0,0 +1,207 @@
+package builder
+
+import (
+	"archive/tar"
+	"bufio"
+	"bytes"
+	"context"
+	"encoding/binary"
+	"errors"
+	"hash/crc32"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+)
+
+// xzStream is one xz stream (no integrity check) of data cut into blocks of blockSize bytes, each block's
+// LZMA2 data stored uncompressed, each block a delta filter before LZMA2 when delta is set: the shape of
+// `xz --block-size=N --filters=delta,lzma2`, built without any xz tool. listed is how many blocks its index
+// lists (-1: as many as it holds), so a stream whose index lies can be built too.
+func xzStream(data []byte, blockSize int, delta bool, listed int) []byte {
+	var out bytes.Buffer
+	flags := []byte{0, 0}
+	out.Write([]byte{0xfd, '7', 'z', 'X', 'Z', 0x00})
+	out.Write(flags)
+	out.Write(binary.LittleEndian.AppendUint32(nil, crc32.ChecksumIEEE(flags)))
+	type record struct{ unpadded, uncompressed uint64 }
+	var records []record
+	for at := 0; at < len(data); at += blockSize {
+		block := data[at:min(at+blockSize, len(data))]
+		if delta {
+			// Delta-encoded with a distance of one; the decoder's history starts empty at each block.
+			encoded := make([]byte, len(block))
+			for i := range block {
+				encoded[i] = block[i]
+				if i > 0 {
+					encoded[i] -= block[i-1]
+				}
+			}
+			block = encoded
+		}
+		header := []byte{2, 0} // 12 bytes
+		if delta {
+			header[1] = 1 // two filters
+			header = append(header, 0x03, 0x01, 0x00)
+		}
+		header = append(header, 0x21, 0x01, 0x00) // LZMA2, a 4 KiB dictionary
+		for len(header) < 8 {
+			header = append(header, 0)
+		}
+		header = binary.LittleEndian.AppendUint32(header, crc32.ChecksumIEEE(header))
+		out.Write(header)
+		size := 0
+		for i, chunk := 0, block; len(chunk) > 0; i++ {
+			n := min(len(chunk), 1<<16)
+			control := byte(2)
+			if i == 0 {
+				control = 1 // the first chunk of a block resets the dictionary
+			}
+			out.WriteByte(control)
+			out.Write(binary.BigEndian.AppendUint16(nil, uint16(n-1)))
+			out.Write(chunk[:n])
+			size += 3 + n
+			chunk = chunk[n:]
+		}
+		out.WriteByte(0)
+		size++
+		out.Write(make([]byte, (4-size%4)%4))
+		records = append(records, record{uint64(len(header) + size), uint64(len(block))})
+	}
+	if listed >= 0 {
+		for len(records) < listed {
+			records = append(records, records[0])
+		}
+		records = records[:listed]
+	}
+	vli := func(b []byte, v uint64) []byte {
+		for v >= 0x80 {
+			b = append(b, byte(v)|0x80)
+			v >>= 7
+		}
+		return append(b, byte(v))
+	}
+	index := vli([]byte{0}, uint64(len(records)))
+	for _, r := range records {
+		index = vli(vli(index, r.unpadded), r.uncompressed)
+	}
+	for len(index)%4 != 0 {
+		index = append(index, 0)
+	}
+	index = binary.LittleEndian.AppendUint32(index, crc32.ChecksumIEEE(index))
+	out.Write(index)
+	footer := binary.LittleEndian.AppendUint32(nil, uint32(len(index)/4-1))
+	footer = append(footer, flags...)
+	out.Write(binary.LittleEndian.AppendUint32(nil, crc32.ChecksumIEEE(footer)))
+	out.Write(footer)
+	out.WriteString("YZ")
+	return out.Bytes()
+}
+
+// tarHolding is a tar holding betterbird/data with body.
+func tarHolding(t *testing.T, body []byte) []byte {
+	t.Helper()
+	var out bytes.Buffer
+	w := tar.NewWriter(&out)
+	if err := w.WriteHeader(&tar.Header{Name: "betterbird/data", Mode: 0o644, Size: int64(len(body)),
+		Typeflag: tar.TypeReg}); err != nil {
+		t.Fatal(err)
+	}
+	w.Write(body)
+	if err := w.Close(); err != nil {
+		t.Fatal(err)
+	}
+	return out.Bytes()
+}
+
+func writeTemp(t *testing.T, body []byte) string {
+	t.Helper()
+	file := filepath.Join(t.TempDir(), "r.tar.xz")
+	if err := os.WriteFile(file, body, 0o644); err != nil {
+		t.Fatal(err)
+	}
+	return file
+}
+
+func TestAnXzFileOfAFewDeltaBlocksAndTwoStreamsIsRead(t *testing.T) {
+	// The streams this test builds are ones the reader decodes, so what the walk refuses below is the
+	// same framing the reader follows.
+	body := bytes.Repeat([]byte("betterbird "), 300)
+	whole := tarHolding(t, body)
+	half := len(whole) / 2
+	for name, file := range map[string][]byte{
+		"one stream of delta blocks": xzStream(whole, 512, true, -1),
+		"two streams with padding": append(append(xzStream(whole[:half], 700, true, -1), 0, 0, 0, 0),
+			xzStream(whole[half:], 100, false, -1)...),
+	} {
+		path := writeTemp(t, file)
+		if xzPath, err := exec.LookPath("xz"); err == nil {
+			if out, err := exec.Command(xzPath, "-t", path).CombinedOutput(); err != nil {
+				t.Fatalf("%s: xz itself refuses the built stream: %v %s", name, err, out)
+			}
+		}
+		into := t.TempDir()
+		if err := unpackUpstream(context.Background(), path, into, "betterbird"); err != nil {
+			t.Fatalf("%s: %v", name, err)
+		}
+		got, err := os.ReadFile(filepath.Join(into, "data"))
+		if err != nil || !bytes.Equal(got, body) {
+			t.Fatalf("%s: unpacked %d bytes, want %d: %v", name, len(got), len(body), err)
+		}
+	}
+}
+
+func TestAnXzFileOfManyDeltaBlocksIsRefusedBeforeItIsDecoded(t *testing.T) {
+	// Review 68 on pull request 264: `xz --block-size=1 --delta` of a 200 kB tar kept about 67 MiB live in
+	// the reader, one delta decoder per block. Its index here lists one block, as a file crafted to pass a
+	// check of the index alone would; the walk counts the blocks the reader would decode.
+	body := make([]byte, 200_000)
+	for i := range body {
+		body[i] = byte(i * 7)
+	}
+	crafted := xzStream(tarHolding(t, body), 1, true, 1)
+	path := writeTemp(t, crafted)
+	var before, after runtime.MemStats
+	runtime.GC()
+	runtime.ReadMemStats(&before)
+	err := unpackUpstream(context.Background(), path, t.TempDir(), "betterbird")
+	runtime.ReadMemStats(&after)
+	if err == nil || !strings.Contains(err.Error(), "more than 1024 xz blocks") {
+		t.Fatalf("a file of %d bytes in blocks of one byte was not refused for its blocks: %v", len(crafted), err)
+	}
+	if grew := after.TotalAlloc - before.TotalAlloc; grew > 4<<20 {
+		t.Fatalf("%d bytes were allocated for a refused file", grew)
+	}
+}
+
+func TestTheXzBlockLimitIsExact(t *testing.T) {
+	data := make([]byte, xzBlocksMax+1)
+	streams, blocks, err := xzFraming(bufio.NewReader(bytes.NewReader(xzStream(data[:xzBlocksMax], 1, true, -1))))
+	if err != nil || streams != 1 || blocks != xzBlocksMax {
+		t.Fatalf("%d blocks: %d streams, %d blocks, %v", xzBlocksMax, streams, blocks, err)
+	}
+	if _, _, err := xzFraming(bufio.NewReader(bytes.NewReader(xzStream(data, 1, true, -1)))); !errors.Is(err, errXzTooManyBlocks) {
+		t.Fatalf("%d blocks: %v", xzBlocksMax+1, err)
+	}
+}
+
+func TestAnXzFileOfTooManyStreamsIsRefused(t *testing.T) {
+	var file []byte
+	for i := 0; i <= xzStreamsMax; i++ {
+		file = append(file, xzStream([]byte("x"), 1, false, -1)...)
+	}
+	err := unpackUpstream(context.Background(), writeTemp(t, file), t.TempDir(), "")
+	if err == nil || !strings.Contains(err.Error(), "more than 16 concatenated xz streams") {
+		t.Fatalf("%v", err)
+	}
+}
+
+func TestAnXzIndexThatDoesNotListItsBlocksIsRefused(t *testing.T) {
+	file := xzStream(tarHolding(t, []byte("x")), 512, false, 1)
+	err := unpackUpstream(context.Background(), writeTemp(t, file), t.TempDir(), "betterbird")
+	if err == nil || !strings.Contains(err.Error(), "its index lists 1 blocks, but it holds 4") {
+		t.Fatalf("%v", err)
+	}
+}

internal/catalogue/bound_into_files.go

@@ -26,21 +26,10 @@ import (
 // serves — whose keys are agreed by the requirement's name, not by this file.
 
 // bound is where a module says a value from one of its bindings belongs:
-// ${bound:<provision>.<key>}.
-var bound = regexp.MustCompile(`\$\{bound:([a-z0-9][a-z0-9.-]*[a-z0-9]):([a-z0-9][a-z0-9_-]*)\}`)
-
-// boundUsed are the (provision, key) pairs a file's content asks for, first appearance first.
-func boundUsed(content string) [][2]string {
-	var used [][2]string
-	seen := map[string]bool{}
-	for _, m := range bound.FindAllStringSubmatch(content, -1) {
-		if key := m[1] + ":" + m[2]; !seen[key] {
-			seen[key] = true
-			used = append(used, [2]string{m[1], m[2]})
-		}
-	}
-	return used
-}
+// ${bound:<provision>:<key>}, and for an optional requirement the value it takes while absent,
+// ${bound:<provision>:<key>|default:<value>} (novox/hq ADR 0330 §4). A default is never empty: an
+// absent requirement is never rendered as an empty string.
+var bound = regexp.MustCompile(`\$\{bound:([a-z0-9][a-z0-9.-]*[a-z0-9]):([a-z0-9][a-z0-9_-]*)(?:\|default:([^}\n]+))?\}`)
 
 // knownFor is everything a module may name from one of its bindings.
 //
@@ -125,7 +114,11 @@ func plainly(value any) string {
 // serve, is refused. Left as it was, the literal `${bound:x:y}` would be written into a
 // configuration file and read as a value — a connection to a host called `${bound:x:y}`, failing
 // somewhere that names neither the module nor the mesh.
-func boundInto(resource map[string]any, known map[string]map[string]string, module string) error {
+//
+// **An optional requirement left absent takes the default its placeholder names** (novox/hq ADR
+// 0330 §4), and one that names none is refused rather than rendered empty. The module check refuses
+// that already; this is the same rule where the file is made, for a manifest registered before it.
+func boundInto(resource map[string]any, known map[string]map[string]string, module string, absent map[string]bool) error {
 	if fmt.Sprint(resource["type"]) != "file" {
 		return nil
 	}
@@ -133,24 +126,43 @@ func boundInto(resource map[string]any, known map[string]map[string]string, modu
 	if !ok {
 		return nil
 	}
-	for _, pair := range boundUsed(content) {
-		provision, key := pair[0], pair[1]
+	var refused error
+	filled := bound.ReplaceAllStringFunc(content, func(token string) string {
+		if refused != nil {
+			return token
+		}
+		m := bound.FindStringSubmatch(token)
+		provision, key, fallback := m[1], m[2], m[3]
 		values, has := known[provision]
 		if !has {
-			return fmt.Errorf(
+			if absent[provision] {
+				if fallback != "" {
+					return fallback
+				}
+				refused = fmt.Errorf(
+					"%s has a file that says ${bound:%s:%s}, and %q is optional and absent here: it names no "+
+						"value for then (${bound:%s:%s|default:<value>}), so it would be written empty "+
+						"(novox/hq ADR 0330 §4)", module, provision, key, provision, provision, key)
+				return token
+			}
+			refused = fmt.Errorf(
 				"%s has a file that says ${bound:%s:%s}, and %s does not require %q. It may name %s",
 				module, provision, key, module, provision, orNothing(namesOfBindings(known)))
+			return token
 		}
 		value, said := values[key]
 		if !said {
-			return fmt.Errorf(
+			refused = fmt.Errorf(
 				"%s asks its %s binding for %q, and what answers it says %s",
 				module, provision, key, orNothing(namesOfKeys(values)))
+			return token
 		}
-		resource["content"] = strings.ReplaceAll(
-			content, fmt.Sprintf("${bound:%s:%s}", provision, key), value)
-		content = resource["content"].(string)
+		return value
+	})
+	if refused != nil {
+		return refused
 	}
+	resource["content"] = filled
 	return nil
 }
 

internal/catalogue/build.go

@@ -2,7 +2,10 @@ package catalogue
 
 import (
 	"fmt"
+	"net"
+	"net/url"
 	"path"
+	"regexp"
 	"sort"
 	"strings"
 )
@@ -312,7 +315,7 @@ func (b *Build) problems(module string) []string {
 					module, a.Name, a.System, spokenSystems()))
 			}
 		} else {
-			if a.From == "" {
+			if a.From == "" && a.URL == "" {
 				problems = append(problems, fmt.Sprintf(
 					"%s: %q says nothing about what it is built from", module, a.Name))
 			}
@@ -350,6 +353,85 @@ func (b *Build) problems(module string) []string {
 			problems = append(problems, fmt.Sprintf(
 				"%s: %q mirrors %q, which names no tag or digest", module, a.Name, a.From))
 		}
+		problems = append(problems, upstreamFileProblems(module, a)...)
+	}
+	return problems
+}
+
+// reservedSuffixes are names no public vendor publishes under: an installation's own and documentation's.
+var reservedSuffixes = []string{".internal", ".local", ".lan", ".home", ".corp", ".localhost", ".home.arpa",
+	".test", ".invalid", ".example", ".intranet", ".private"}
+
+// notAPublicHost says why a host is not a public vendor's name, or "".
+func notAPublicHost(host string) string {
+	h := strings.ToLower(strings.TrimSuffix(host, "."))
+	if net.ParseIP(h) != nil {
+		return "an address rather than a name"
+	}
+	if !strings.Contains(h, ".") {
+		return "a name with no domain"
+	}
+	for _, s := range reservedSuffixes {
+		if strings.HasSuffix(h, s) {
+			return "a name under " + s + ", which is nobody's public domain"
+		}
+	}
+	return ""
+}
+
+// sha256Hex is a pinned sha256 as a manifest writes it: 64 lower-case hexadecimal characters.
+var sha256Hex = regexp.MustCompile(`^[0-9a-f]{64}$`)
+
+// upstreamFileProblems is what is wrong with an archive pinned by URL (novox/hq ADR 0316 §2, §6): it is an
+// archive, fetched over https, pinned by a sha256 and a version, and it names no directory of the repository
+// besides; a file name or a directory within is a plain path that stays where it is put.
+func upstreamFileProblems(module string, a Artifact) []string {
+	pinned := a.URL != "" || a.SHA256 != "" || a.Version != "" || a.File != "" || a.Within != ""
+	if !pinned {
+		return nil
+	}
+	var problems []string
+	say := func(format string, args ...any) {
+		problems = append(problems, fmt.Sprintf("%s: %q ", module, a.Name)+fmt.Sprintf(format, args...))
+	}
+	if a.Kind != ArtifactArchive {
+		say("is a %q and names an upstream file (url, sha256, version, file, within): only an archive is "+
+			"mirrored from one (novox/hq ADR 0316)", a.Kind)
+		return problems
+	}
+	if a.URL == "" {
+		say("names a sha256, a version, a file or a directory within, and no url to fetch it from")
+		return problems
+	}
+	if a.From != "" {
+		say("is built from %q and fetched from %s: an archive is one or the other", a.From, a.URL)
+	}
+	if u, err := url.Parse(a.URL); err != nil || u.Scheme != "https" || u.Host == "" {
+		say("is fetched from %q, and an upstream file is fetched over https from a named host", a.URL)
+	} else if why := notAPublicHost(u.Hostname()); why != "" {
+		say("is fetched from %s, %s: an upstream file is somebody else's release, published under a public name", a.URL, why)
+	}
+	if !sha256Hex.MatchString(a.SHA256) {
+		say("is fetched from %s without a pinned sha256 (64 lower-case hexadecimal characters): what that "+
+			"address serves changes under the mesh, and only the digest says it is what was reviewed", a.URL)
+	}
+	if strings.TrimSpace(a.Version) == "" {
+		say("pins %s and says no version, so a person reading the pin cannot tell which release it is", a.URL)
+	}
+	if a.File != "" && a.Within != "" {
+		say("names a file (%q) and a directory within (%q): a file is kept whole, a directory is taken out "+
+			"of an archive", a.File, a.Within)
+	}
+	for field, p := range map[string]string{"file": a.File, "within": a.Within} {
+		if p == "" {
+			continue
+		}
+		clean := path.Clean(p)
+		if clean != p || strings.HasPrefix(p, "/") || clean == "." || clean == ".." || strings.HasPrefix(clean, "../") ||
+			(field == "file" && strings.Contains(p, "/")) {
+			say("names %s %q, which is not a plain relative %s", field, p, map[string]string{
+				"file": "file name", "within": "directory"}[field])
+		}
 	}
 	return problems
 }

internal/catalogue/declaration.go

@@ -645,6 +645,11 @@ func (r Resolution) compose(with Rendering, owner map[string]string,
 				sealed = ForeseenSealed
 				*foreseen = append(*foreseen, m.Module+"/"+name)
 			}
+			if sealed == "" && m.OwnSecrets[name].IssuedBy == IssuedOutside {
+				// **Not given, and the mesh never makes it** (novox/hq issue 401, ADR 0228): no file, as for a
+				// family's member (ADR 0283), so the module reads its absence as not given.
+				continue
+			}
 			if sealed == "" {
 				// Declared and not made. Refused rather than skipped: a module whose own
 				// credential is silently absent starts, fails to authenticate, and the reason is
@@ -845,6 +850,11 @@ func (r Resolution) compose(with Rendering, owner map[string]string,
 		// An account depends on nothing the mesh computes.
 		accounts, rest := accountsFirst(resources)
 		resources = append(append(accounts, first...), rest...)
+		// **A file delivered only while its optional requirement is bound is left out while it is
+		// absent** (novox/hq ADR 0330 §5), and the field is dropped from the rest: the node-engine
+		// parses strictly and knows no such field.
+		absent := r.AbsentFor(m.Module)
+		resources = withoutAbsent(resources, absent)
 
 		// No container is given the mesh's names (novox/hq ADR 0148). It used to be: every
 		// container got the whole roster as `--add-host` entries at creation, and a name that
@@ -1002,13 +1012,13 @@ func (r Resolution) compose(with Rendering, owner map[string]string,
 			// content is where a setting lands, so a placeholder may only exist once the setting
 			// has been put in — filling secrets first would look at content that is not yet what
 			// the machine receives.
-			if err := intoFile(copied, sealed, m.Module); err != nil {
+			if err := intoFile(copied, sealed, outsideNotGiven(m, with.Needed[m.Module]), m.Module); err != nil {
 				return nil, err
 			}
 			// **Substituted here, not on the machine.** A bound value is not secret — the mesh
 			// holds it in the clear — so there is nothing for the host to be the only witness of,
 			// and sending it already filled in means the host learns no new field.
-			if err := boundInto(copied, known, m.Module); err != nil {
+			if err := boundInto(copied, known, m.Module, absent); err != nil {
 				return nil, err
 			}
 			// And what the module could not have written: the machine it turned out to be
@@ -2431,6 +2441,9 @@ func secretsReadBy(resource map[string]any, m Manifest, given map[string]string)
 	}
 	paths := map[string]string{}
 	for name, own := range m.OwnSecrets.Plain() {
+		if own.IssuedBy == IssuedOutside && given[name] == "" {
+			continue // not given, so not placed: nothing to restart on (novox/hq issue 401)
+		}
 		paths[name] = own.Path
 	}
 	for name, sealed := range given {

internal/catalogue/installation.go

@@ -71,6 +71,9 @@ var hostname = regexp.MustCompile(
 		`(?:be|nl|de|fr|uk|eu|com|net|org|io|dev|app|cloud|site|online|me|co|ch|at|lu|` +
 		`internal|example|tld|test|invalid)`)
 
+// upstreamVersion is where an artifact pinned by URL says which release it is (Artifact.Version).
+var upstreamVersion = regexp.MustCompile(`^build\.artifacts\[[0-9]+\]\.version$`)
+
 // address is a dotted quad.
 var address = regexp.MustCompile(`(?:[0-9]{1,3}\.){3}[0-9]{1,3}`)
 
@@ -120,7 +123,10 @@ func InstallationProblems(m Manifest) []string {
 			problems = append(problems, fmt.Sprintf("%s names %s at %s", m.Module, name, at))
 		}
 		for _, ip := range addressesIn(value) {
-			if meant[ip] {
+			// An upstream pin's version may have four dotted numbers (Owl 1.5.6.1), which is no address; a name
+			// in it is still judged above. Its URL is judged whole: the vendor's host goes through the artifact's
+			// names-on-purpose like any name a definition means (novox/hq ADR 0316).
+			if meant[ip] || upstreamVersion.MatchString(at) {
 				continue
 			}
 			problems = append(problems, fmt.Sprintf("%s names the public address %s at %s", m.Module, ip, at))

internal/catalogue/manifest.go

@@ -385,6 +385,10 @@ type Manifest struct {
 
 	// Requires are names that must be provided by something assigned to the same node.
 	Requires []string `json:"requires,omitempty"`
+	// OptionalRequires is which of Requires the module can run without (novox/hq ADR 0330): filled
+	// by UnmarshalJSON from the long form of a `requires` entry, {name, optional}, or from the stored
+	// form's `optional-requires` list; never written by hand.
+	OptionalRequires map[string]bool `json:"-"`
 
 	// Emits are the events this module publishes, named **locally**: `order.placed`, not a subject
 	// and not a routing key. The mesh derives where it lands (design 29 §1), so reorganising the
@@ -976,6 +980,35 @@ type Artifact struct {
 	// success, and was invisible to the launcher (novox/hq 04-ISSUES/142).
 	Binary string `json:"binary,omitempty"`
 
+	// URL is where an archive's upstream file is fetched from, for an archive that is a release
+	// somebody else published rather than a directory of this repository (novox/hq ADR 0316 §2, §6).
+	// With it come SHA256 and Version, and From stays empty.
+	//
+	// **Pinned by the digest of what the vendor published, mirrored by the build seat.** A release of
+	// about 80 MB copied into a repository is kept for ever in its history at every upgrade, and an
+	// add-on whose licence forbids copying it to third parties may not be in a repository at all. So the
+	// manifest names the file, the build seat fetches it, refuses it when its sha256 is not the pin's and
+	// names both digests, and packs it as any archive is packed: what reaches a machine is the mesh's own
+	// archive in the artifact store, fetched by digest like every other, and a machine never asks the
+	// vendor. Upgrading is changing the pin, reviewed like any other change.
+	URL string `json:"url,omitempty"`
+	// SHA256 is the sha256 of the file at URL, as 64 lower-case hexadecimal characters.
+	SHA256 string `json:"sha256,omitempty"`
+	// Version is what the vendor calls the release pinned, said where a person reads the pin; the build
+	// does not read it.
+	Version string `json:"version,omitempty"`
+	// File is the name an upstream file that is not an archive is kept under: the archive built from it
+	// holds that one file (an add-on's xpi). Empty means the file is a tar archive (gzip, bzip2 or xz)
+	// whose files are the artifact.
+	File string `json:"file,omitempty"`
+	// Within is the directory inside an upstream tar archive whose content is the artifact, for a
+	// release that unpacks into a directory of its own name (`betterbird/`). An entry outside it refuses
+	// the build. Empty means the archive's root.
+	Within string `json:"within,omitempty"`
+	// NamesOnPurpose are the names this artifact means to name, each with why: the vendor's host an upstream
+	// file is fetched from, which the installation check judges like any name (InstallationProblems).
+	NamesOnPurpose map[string]string `json:"names-on-purpose,omitempty"`
+
 	// Entrypoints are the compiled files a tool host should load from this module, relative to the
 	// bundle's root.
 	//
@@ -1325,6 +1358,35 @@ func (m *Manifest) UnmarshalJSON(raw []byte) error {
 		}
 		delete(keys, "contributes")
 	}
+	var optionalRequires map[string]bool
+	if requires, ok := keys["requires"]; ok && string(requires) != "null" {
+		names, optional, err := readRequires(requires)
+		if err != nil {
+			return err
+		}
+		plainNames, err := json.Marshal(names)
+		if err != nil {
+			return err
+		}
+		keys["requires"] = plainNames
+		optionalRequires = optional
+	}
+	// The stored form: `requires` plain, and which are optional beside it (OptionalRequiresKey).
+	if stored, ok := keys[OptionalRequiresKey]; ok {
+		if string(stored) != "null" {
+			optional, err := readOptionalRequires(stored)
+			if err != nil {
+				return err
+			}
+			for name := range optional {
+				if optionalRequires == nil {
+					optionalRequires = map[string]bool{}
+				}
+				optionalRequires[name] = true
+			}
+		}
+		delete(keys, OptionalRequiresKey)
+	}
 	rest, err := json.Marshal(keys)
 	if err != nil {
 		return err
@@ -1356,6 +1418,7 @@ func (m *Manifest) UnmarshalJSON(raw []byte) error {
 	}
 	*m = Manifest(fields)
 	m.unknown = unknown
+	m.OptionalRequires = optionalRequires
 	if len(plain) > 0 {
 		m.Secrets = plain
 	}
@@ -1378,13 +1441,22 @@ func (m Manifest) MarshalJSON() ([]byte, error) {
 	if err != nil {
 		return nil, err
 	}
-	if len(m.SecretsMany) == 0 && len(m.ContributesMany) == 0 {
+	if len(m.SecretsMany) == 0 && len(m.ContributesMany) == 0 && len(m.OptionalRequires) == 0 {
 		return raw, nil
 	}
 	var keys map[string]json.RawMessage
 	if err := json.Unmarshal(raw, &keys); err != nil {
 		return nil, err
 	}
+	if optional := optionalRequiresList(m); len(optional) > 0 {
+		// Beside `requires`, never inside it: an older controller reads `requires` as plain names, and one
+		// manifest it cannot read stops the whole catalogue (OptionalRequiresKey).
+		listed, err := json.Marshal(optional)
+		if err != nil {
+			return nil, err
+		}
+		keys[OptionalRequiresKey] = listed
+	}
 	if len(m.ContributesMany) > 0 {
 		mergedContributes := map[string]any{}
 		for to, values := range m.Contributes {
@@ -1664,6 +1736,10 @@ func ParseManifest(raw []byte) (Manifest, error) {
 	problems = append(problems, LogProblems(m)...)
 	// And the defaults it gives its settings (setting_defaults.go, novox/hq ADR 0262).
 	problems = append(problems, SettingProblems(m)...)
+	// And what it requires optionally, and the files it delivers only while bound (novox/hq ADR 0330).
+	problems = append(problems, OptionalProblems(m)...)
+	// And which setting keys each mergeable file takes (setting_takes.go, novox/hq ADR 0326).
+	problems = append(problems, TakenSettingsProblems(m)...)
 	wellFormed := true
 	for _, c := range m.Claims {
 		if !name.MatchString(c.Name) {
@@ -1689,6 +1765,7 @@ func ParseManifest(raw []byte) (Manifest, error) {
 	// facts about the catalogue and are checked at registration (CatalogueProblems).
 	problems = append(problems, declaredSeatProblems(m)...)
 	problems = append(problems, RunsAsProblems(m)...)
+	problems = append(problems, ReadsHolderProblems(m)...)
 	if m.Computed != "" && len(m.Resources) > 0 {
 		// One or the other. A module that both ships files and has them computed would leave
 		// nobody able to say where a given file came from.
@@ -1829,6 +1906,7 @@ func ParseManifest(raw []byte) (Manifest, error) {
 	problems = append(problems, invokeProblems(m)...)
 	problems = append(problems, replacesProblems(m)...)
 	problems = append(problems, UnitSettingProblems(m)...)
+	problems = append(problems, OwnerSettingProblems(m)...)
 	problems = append(problems, endpointNameProblems(m)...)
 	problems = append(problems, RouteProblems(m)...)
 	for _, port := range m.Guards {

internal/catalogue/node_resolver.go

@@ -1,5 +1,7 @@
 package catalogue
 
+import "path"
+
 // The machine's own resolver (novox/hq ADR 0247).
 //
 // **Most machines have none.** Every machine lists the mesh's resolvers in /etc/resolv.conf and nothing
@@ -66,43 +68,39 @@ func holdsSeat(m Manifest, seat string) bool {
 	return false
 }
 
-// rendersResolverFile says whether a module asks the mesh to render the machine's resolver file.
-func rendersResolverFile(m Manifest) bool {
-	for _, f := range m.Facts {
-		if !f.Home && f.Path == ResolverFile {
-			return true
-		}
-	}
-	return false
-}
-
-// ResolverFileOwner is the module that writes the machine's resolver file among the modules on one
-// machine (novox/hq ADR 0247): the holder of node-resolver when one renders it, else nobody is named here
-// and the file is whoever's it always was — the uplink holder's (ADR 0223).
-func ResolverFileOwner(modules []Manifest) string {
-	for _, m := range modules {
-		if holdsSeat(m, ResolverSeat) && rendersResolverFile(m) {
-			return m.Module
-		}
-	}
-	return ""
-}
-
-// stepsBack is the module as it composes on a machine whose resolver file is the node-resolver holder's:
-// **the uplink holder's rendering of that file is left out**, and nothing else of it changes. Only the
-// uplink's holder steps back — any other module rendering the file beside the resolver's is still two
-// owners of one path, and is refused as before.
+// stepsBack is the module as it composes among the modules of one machine (novox/hq ADR 0287,
+// ADR 0247):
+// **where it holds a seat that names a path stepping back for another seat, and that other seat's holder
+// is on the machine and declares the path, its own rendering of the path is left out**, and nothing else
+// of it changes. Only a file the mesh renders for it steps back, as before: a resource on the path is
+// composed as declared (the declaration copies a module's resources whole), so an uplink holder declaring
+// the resolver file as a resource beside the resolver's holder is two owners of one path, and refused. The stepping back is the seat's definition — node-uplink stepping back from the resolver
+// file for node-resolver — so any other module declaring the path beside the owner's is still two owners
+// of one path, and is refused as before.
 func stepsBack(m Manifest, modules []Manifest) Manifest {
-	if !holdsSeat(m, "node-uplink") || !rendersResolverFile(m) {
-		return m
+	drop := map[string]bool{}
+	for _, c := range m.Claims {
+		seat, known := SeatNamed(c.Name)
+		if !known {
+			continue
+		}
+		for _, p := range seat.Paths {
+			if p.StepsBackFor == "" {
+				continue
+			}
+			for _, o := range modules {
+				if o.Module != m.Module && holdsSeat(o, p.StepsBackFor) && declaresPath(o, p.Path) {
+					drop[p.Path] = true
+				}
+			}
+		}
 	}
-	owner := ResolverFileOwner(modules)
-	if owner == "" || owner == m.Module {
+	if len(drop) == 0 {
 		return m
 	}
 	facts := make(map[string]RosterFile, len(m.Facts))
 	for name, f := range m.Facts {
-		if !f.Home && f.Path == ResolverFile {
+		if !f.Home && drop[path.Clean(f.Path)] {
 			continue
 		}
 		facts[name] = f
@@ -113,9 +111,6 @@ func stepsBack(m Manifest, modules []Manifest) Manifest {
 
 // steppedBack is every module of one machine as it composes there (stepsBack, each).
 func steppedBack(modules []Manifest) []Manifest {
-	if ResolverFileOwner(modules) == "" {
-		return modules
-	}
 	out := make([]Manifest, len(modules))
 	for i, m := range modules {
 		out[i] = stepsBack(m, modules)

internal/catalogue/operators_machine_test.go

@@ -68,9 +68,10 @@ func TestFailedIsAnOptionalVerbOfTheServiceManager(t *testing.T) {
 	holder := func(serves ...string) Manifest {
 		return Manifest{Module: "systemd", Version: "1", Claims: []Claim{{Name: ServiceManagerSeat, Scope: ScopeNode, Serves: serves}}}
 	}
-	eight := []string{"units", "status", "start", "stop", "restart", "enable", "disable", "journal"}
+	eight := []string{"units", "status", "start", "stop", "restart", "enable", "disable", "journal",
+		"reset-failed", "wanted-by", "unlink-dangling"}
 	if err := CanHold(holder(eight...), seat); err != nil {
-		t.Fatalf("today's holder, without failed, is refused: %v", err)
+		t.Fatalf("a holder without failed is refused: %v", err)
 	}
 	if err := CanHold(holder(append(eight, "failed")...), seat); err != nil {
 		t.Fatalf("a holder serving failed is refused: %v", err)
@@ -81,7 +82,7 @@ func TestFailedIsAnOptionalVerbOfTheServiceManager(t *testing.T) {
 	if err := CanHold(holder(eight[1:]...), seat); err == nil || !strings.Contains(err.Error(), "does not serve units") {
 		t.Fatalf("a holder missing a required verb was accepted: %v", err)
 	}
-	optional := map[string]bool{"failed": true, "reset-failed": true, "wanted-by": true, "unlink-dangling": true}
+	optional := map[string]bool{"failed": true}
 	for _, v := range seat.Serves {
 		if v.Optional != optional[v.Name] {
 			t.Errorf("%s optional: %v", v.Name, v.Optional)
@@ -89,26 +90,35 @@ func TestFailedIsAnOptionalVerbOfTheServiceManager(t *testing.T) {
 	}
 }
 
-// **`reset-failed` and `wanted-by` join the seat optional** (novox/hq issue 332, ADR 0246 step 1): the
-// holder running today, serving the nine verbs, still holds the seat; a holder serving all eleven is not
-// refused; each replaces the shell command it names; and read back from the store's row they stay optional.
-func TestResetFailedAndWantedByAreOptionalVerbsOfTheServiceManager(t *testing.T) {
+// **`reset-failed`, `wanted-by` and `unlink-dangling` are required** (novox/hq issue 332, ADR 0246 step 3):
+// every holder serves them, so a holder serving only the nine verbs before them is refused by the verb it
+// lacks; a holder serving all twelve holds the seat; each replaces the shell command it names; and read
+// back from the store's row they stay required.
+func TestResetFailedWantedByAndUnlinkDanglingAreRequiredVerbsOfTheServiceManager(t *testing.T) {
 	defer UseSeats(DefaultSeats())
 	nine := []string{"units", "status", "start", "stop", "restart", "enable", "disable", "journal", "failed"}
+	all := append(slices.Clone(nine), "reset-failed", "wanted-by", "unlink-dangling")
 	holder := func(serves ...string) Manifest {
 		return Manifest{Module: "systemd", Version: "1", Claims: []Claim{{Name: ServiceManagerSeat, Scope: ScopeNode, Serves: serves}}}
 	}
+	refusedWithout := func(seat Seat) {
+		t.Helper()
+		for _, verb := range []string{"reset-failed", "wanted-by", "unlink-dangling"} {
+			serves := slices.DeleteFunc(slices.Clone(all), func(v string) bool { return v == verb })
+			if err := CanHold(holder(serves...), seat); err == nil || !strings.Contains(err.Error(), "does not serve "+verb) {
+				t.Errorf("a holder not serving %s holds the seat: %v", verb, err)
+			}
+		}
+	}
 	seat, _ := SeatNamed(ServiceManagerSeat)
-	if err := CanHold(holder(nine...), seat); err != nil {
-		t.Fatalf("today's holder, without the two verbs, is refused: %v", err)
+	if err := CanHold(holder(nine...), seat); err == nil {
+		t.Fatal("a holder serving only the nine verbs before issue 332 holds the seat")
 	}
-	if err := CanHold(holder(append(nine, "reset-failed", "wanted-by")...), seat); err != nil {
-		t.Fatalf("a holder serving both is refused: %v", err)
+	refusedWithout(seat)
+	if err := CanHold(holder(all...), seat); err != nil {
+		t.Fatalf("a holder serving all twelve is refused: %v", err)
 	}
-	if err := CanHold(holder(append(nine, "reset-failed", "wanted-by", "unlink-dangling")...), seat); err != nil {
-		t.Fatalf("a holder serving unlink-dangling too is refused: %v", err)
-	}
-	if err := CanHold(holder(append(nine, "why-started")...), seat); err == nil || !strings.Contains(err.Error(), "does not promise") {
+	if err := CanHold(holder(append(slices.Clone(all), "why-started")...), seat); err == nil || !strings.Contains(err.Error(), "does not promise") {
 		t.Fatalf("a verb the seat does not promise was accepted: %v", err)
 	}
 	replaces := map[string]string{"reset-failed": "systemctl reset-failed", "wanted-by": "systemctl list-dependencies --reverse",
@@ -118,6 +128,9 @@ func TestResetFailedAndWantedByAreOptionalVerbsOfTheServiceManager(t *testing.T)
 		if !ok {
 			continue
 		}
+		if v.Optional {
+			t.Errorf("%s is still optional", v.Name)
+		}
 		if !slices.Contains(v.Replaces, want) {
 			t.Errorf("%s does not say it replaces %q: %v", v.Name, want, v.Replaces)
 		}
@@ -148,8 +161,9 @@ func TestResetFailedAndWantedByAreOptionalVerbsOfTheServiceManager(t *testing.T)
 	}
 	UseSeats(rows)
 	seat, _ = SeatNamed(ServiceManagerSeat)
-	if err := CanHold(holder(nine...), seat); err != nil {
-		t.Fatalf("read back from the row, the two verbs are required: %v", err)
+	refusedWithout(seat)
+	if err := CanHold(holder(all...), seat); err != nil {
+		t.Fatalf("read back from the row, a holder serving all twelve is refused: %v", err)
 	}
 }
 
@@ -169,8 +183,9 @@ func TestAnOptionalVerbStaysOptionalInASetReadFromTheStore(t *testing.T) {
 	UseSeats(rows)
 	seat, _ := SeatNamed(ServiceManagerSeat)
 	holder := Manifest{Module: "systemd", Version: "1", Claims: []Claim{{Name: ServiceManagerSeat, Scope: ScopeNode,
-		Serves: []string{"units", "status", "start", "stop", "restart", "enable", "disable", "journal"}}}}
+		Serves: []string{"units", "status", "start", "stop", "restart", "enable", "disable", "journal",
+			"reset-failed", "wanted-by", "unlink-dangling"}}}}
 	if err := CanHold(holder, seat); err != nil {
-		t.Fatalf("a set read from rows refuses today's holder: %v", err)
+		t.Fatalf("a set read from rows refuses a holder without the optional failed: %v", err)
 	}
 }

internal/catalogue/optional_requirements.go

@@ -0,0 +1,282 @@
+package catalogue
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"sort"
+	"strings"
+)
+
+// A requirement a module can run without (novox/hq ADR 0330, issue 166).
+//
+// **Hard stays the default.** A requirement written as a bare name is hard, exactly as before: it
+// resolves, or the assignment is refused, and a single catalogue candidate is installed for it. One
+// written `{"name": "influxdb-api", "optional": true}` resolves the same way when a provider is
+// already assigned in the mesh or reachable from the consumer (§2), and is otherwise **absent**: not
+// refused, and nothing is installed for it, on this machine or elsewhere (§3).
+//
+// **An absent requirement is never rendered as an empty value** (§4–§6). Its binding, its pair
+// credential and its grant are not composed, so a file that names one of them is delivered only while
+// the requirement is bound (`only-when-bound`), and a `${bound:…}` placeholder of it outside such a
+// file names the value it takes while absent: `${bound:<provision>:<key>|default:<value>}`. The
+// module check refuses anything else, so the gap is found when the manifest is written, not on a
+// machine where it reads as a blank.
+
+// OnlyWhenBound is a resource's field naming the optional requirement it is delivered only while
+// bound (ADR 0330 §5). Said in the catalogue and dropped before the declaration is sent: the
+// node-engine parses strictly and knows no such field.
+const OnlyWhenBound = "only-when-bound"
+
+// requirementForm is one entry of `requires` in its long form.
+type requirementForm struct {
+	Name     string `json:"name"`
+	Optional bool   `json:"optional,omitempty"`
+}
+
+// readRequires reads `requires` in both of its forms — a bare name, or {name, optional} — into the
+// names and which of them are optional.
+func readRequires(raw json.RawMessage) ([]string, map[string]bool, error) {
+	var entries []json.RawMessage
+	if err := json.Unmarshal(raw, &entries); err != nil {
+		return nil, nil, fmt.Errorf("requires: a list of names, or of {name, optional}: %w", err)
+	}
+	var names []string
+	optional := map[string]bool{}
+	for i, e := range entries {
+		var plain string
+		if err := json.Unmarshal(e, &plain); err == nil {
+			names = append(names, plain)
+			continue
+		}
+		var full requirementForm
+		dec := json.NewDecoder(bytes.NewReader(e))
+		dec.DisallowUnknownFields()
+		if err := dec.Decode(&full); err != nil {
+			return nil, nil, fmt.Errorf("requires[%d]: a name, or {name, optional} (novox/hq ADR 0330): %w", i, err)
+		}
+		if strings.TrimSpace(full.Name) == "" {
+			return nil, nil, fmt.Errorf("requires[%d] names no requirement: {name, optional}", i)
+		}
+		names = append(names, full.Name)
+		if full.Optional {
+			optional[full.Name] = true
+		}
+	}
+	if len(optional) == 0 {
+		optional = nil
+	}
+	return names, optional, nil
+}
+
+// OptionalRequiresKey is where a stored manifest keeps which of its requirements are optional: beside
+// `requires`, which stays a plain list of names (mesh-controller #281's review). A controller older than
+// optional requirements reads `requires` as names; the long form inside it failed that read, and with it
+// the whole catalogue, so a rollback below this controller would have composed no machine. An older
+// controller sets this unknown key aside instead and leaves only the module that carries it out. A
+// manifest may be written either way; it is stored this way.
+const OptionalRequiresKey = "optional-requires"
+
+// readOptionalRequires reads the stored form's list of optional requirements.
+func readOptionalRequires(raw json.RawMessage) (map[string]bool, error) {
+	var names []string
+	if err := json.Unmarshal(raw, &names); err != nil {
+		return nil, fmt.Errorf("%s: a list of the names in `requires` that are optional: %w", OptionalRequiresKey, err)
+	}
+	out := map[string]bool{}
+	for _, n := range names {
+		out[n] = true
+	}
+	return out, nil
+}
+
+// optionalRequiresList is the stored form's list: the optional requirements, sorted.
+func optionalRequiresList(m Manifest) []string {
+	var out []string
+	for name, optional := range m.OptionalRequires {
+		if optional {
+			out = append(out, name)
+		}
+	}
+	sort.Strings(out)
+	return out
+}
+
+// IsOptional is whether this module requires the name optionally (ADR 0330 §1). A name it contributes
+// to without requiring, or requires as a bare name, is hard.
+func (m Manifest) IsOptional(requirement string) bool { return m.OptionalRequires[requirement] }
+
+// wantsHard is whether this module wants the name as a hard requirement: required without
+// `optional`, or contributed to.
+func (m Manifest) wantsHard(name string) bool {
+	for _, w := range m.Wants() {
+		if w == name {
+			return !m.IsOptional(name)
+		}
+	}
+	return false
+}
+
+// Absent is one optional requirement of one consumer that nothing assigned answers (ADR 0330 §3):
+// left unbound rather than refused, and listed by `plan` and `node` (§7).
+type Absent struct {
+	// Consumer is the module that requires it optionally.
+	Consumer string `json:"consumer"`
+	// Requirement is what it requires.
+	Requirement string `json:"requirement"`
+}
+
+// AbsentFor is the optional requirements of one module this resolution leaves unbound.
+func (r Resolution) AbsentFor(module string) map[string]bool {
+	out := map[string]bool{}
+	for _, a := range r.Absent {
+		if a.Consumer == module {
+			out[a.Requirement] = true
+		}
+	}
+	return out
+}
+
+// absentOf is, for each requirement left absent, every module of the set that requires it
+// optionally, sorted by consumer then requirement.
+func absentOf(names map[string]bool, order []string, catalogue map[string]Manifest) []Absent {
+	var out []Absent
+	for _, module := range order {
+		m := catalogue[module]
+		for _, r := range m.Requires {
+			if names[r] && m.IsOptional(r) {
+				out = append(out, Absent{Consumer: module, Requirement: r})
+			}
+		}
+	}
+	sort.Slice(out, func(i, j int) bool {
+		if out[i].Consumer != out[j].Consumer {
+			return out[i].Consumer < out[j].Consumer
+		}
+		return out[i].Requirement < out[j].Requirement
+	})
+	return out
+}
+
+// withoutAbsent drops the resources delivered only while a requirement is bound whose requirement is
+// absent here (ADR 0330 §5), and the field itself from every resource that keeps it.
+func withoutAbsent(resources []map[string]any, absent map[string]bool) []map[string]any {
+	out := make([]map[string]any, 0, len(resources))
+	for _, r := range resources {
+		when, has := r[OnlyWhenBound]
+		if !has {
+			out = append(out, r)
+			continue
+		}
+		if absent[fmt.Sprint(when)] {
+			continue
+		}
+		kept := make(map[string]any, len(r))
+		for k, v := range r {
+			if k != OnlyWhenBound {
+				kept[k] = v
+			}
+		}
+		out = append(out, kept)
+	}
+	return out
+}
+
+// secretNamesOf is every `${secret:…}` name that carries a credential of this requirement: its own
+// name, and each local name it keeps several under (ADR 0094).
+func secretNamesOf(m Manifest, requirement string) []string {
+	names := []string{requirement}
+	for local := range m.SecretsMany[requirement] {
+		names = append(names, local)
+	}
+	sort.Strings(names)
+	return names
+}
+
+// OptionalProblems is what the module check refuses of a manifest's optional requirements and its
+// only-when-bound resources (ADR 0330 §4–§6).
+func OptionalProblems(m Manifest) []string {
+	var problems []string
+	required := map[string]bool{}
+	for _, r := range m.Requires {
+		if required[r] && m.IsOptional(r) {
+			problems = append(problems, fmt.Sprintf("%s requires %q twice; say it once, optional or not", m.Module, r))
+		}
+		required[r] = true
+	}
+	for _, r := range optionalRequiresList(m) {
+		if !required[r] {
+			problems = append(problems, fmt.Sprintf(
+				"%s says %q is optional in %s and does not require it", m.Module, r, OptionalRequiresKey))
+		}
+	}
+	// A contribution is to whoever answers the requirement, so it goes with it: contributing to one
+	// that is optional is allowed, and composed only while it is bound.
+	for _, r := range m.Resources {
+		id := fmt.Sprint(r["id"])
+		when, marked := r[OnlyWhenBound]
+		on := ""
+		if marked {
+			name, ok := when.(string)
+			switch {
+			case !ok || name == "":
+				problems = append(problems, fmt.Sprintf(
+					"%s's resource %s says %s %v; it names one requirement the module requires optionally",
+					m.Module, id, OnlyWhenBound, when))
+				continue
+			case fmt.Sprint(r["type"]) != "file":
+				problems = append(problems, fmt.Sprintf(
+					"%s's resource %s is a %v and says %s: only a file is left out while a requirement is "+
+						"absent (novox/hq ADR 0330 §5)", m.Module, id, r["type"], OnlyWhenBound))
+				continue
+			case !required[name]:
+				problems = append(problems, fmt.Sprintf(
+					"%s's resource %s is delivered only when %q is bound, and %s does not require it",
+					m.Module, id, name, m.Module))
+				continue
+			case !m.IsOptional(name):
+				problems = append(problems, fmt.Sprintf(
+					"%s's resource %s is delivered only when %q is bound, which is a hard requirement and "+
+						"always bound: mark the requirement optional, or drop %s", m.Module, id, name, OnlyWhenBound))
+				continue
+			}
+			on = name
+		}
+		if fmt.Sprint(r["type"]) != "file" {
+			continue
+		}
+		content, _ := r["content"].(string)
+		for _, use := range bound.FindAllStringSubmatch(content, -1) {
+			provision, key, hasDefault := use[1], use[2], use[3] != ""
+			if !m.IsOptional(provision) {
+				if hasDefault {
+					problems = append(problems, fmt.Sprintf(
+						"%s's resource %s gives ${bound:%s:%s} a default, and %q is a hard requirement, always "+
+							"bound: a default it never renders only misleads a reader", m.Module, id, provision, key, provision))
+				}
+				continue
+			}
+			if !hasDefault && on != provision {
+				problems = append(problems, fmt.Sprintf(
+					"%s's resource %s says ${bound:%s:%s}, and %q is optional: while it is absent this would "+
+						"be empty. Name its value then — ${bound:%s:%s|default:<value>} — or deliver the file "+
+						"only while it is bound, with \"%s\": %q (novox/hq ADR 0330 §4)",
+					m.Module, id, provision, key, provision, provision, key, OnlyWhenBound, provision))
+			}
+		}
+		for _, provision := range m.Requires {
+			if !m.IsOptional(provision) || on == provision {
+				continue
+			}
+			for _, name := range secretNamesOf(m, provision) {
+				if strings.Contains(content, "${secret:"+name+"}") {
+					problems = append(problems, fmt.Sprintf(
+						"%s's resource %s says ${secret:%s}, the credential of %q, which is optional and not "+
+							"delivered while absent: deliver the file only while it is bound, with \"%s\": %q "+
+							"(novox/hq ADR 0330 §6)", m.Module, id, name, provision, OnlyWhenBound, provision))
+				}
+			}
+		}
+	}
+	return problems
+}

internal/catalogue/optional_requirements_test.go

@@ -0,0 +1,301 @@
+package catalogue
+
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+)
+
+// A requirement a module can run without (novox/hq ADR 0330, issue 166). The shape of the issue:
+// grafana runs without a data source and requires `influxdb-api` softly; a mesh without influxdb
+// could not assign grafana at all, and one with influxdb in its catalogue would have had it installed
+// for grafana.
+
+func optionalShelf() map[string]Manifest {
+	grafana := Manifest{Module: "grafana", Version: "1", Requires: []string{"influxdb-api", "shell"},
+		OptionalRequires: map[string]bool{"influxdb-api": true, "shell": true}}
+	return shelf(
+		Manifest{Module: "influxdb", Version: "1", Provides: FromAnywhere("influxdb-api")},
+		Manifest{Module: "zsh", Version: "1", Provides: Offers("shell")},
+		grafana,
+		// What wants the same names hard, for the cases where one consumer's optional is another's hard.
+		Manifest{Module: "telegraf", Version: "1", Requires: []string{"influxdb-api"}},
+		Manifest{Module: "editor", Version: "1", Requires: []string{"shell"}},
+		Manifest{Module: "suite", Version: "1", Requires: []string{"editor"}},
+	)
+}
+
+func TestARequirementIsHardUnlessMarkedOptional(t *testing.T) {
+	m := mustParse(t, `{"module":"grafana","version":"1",
+		"requires":["route",{"name":"influxdb-api","optional":true},{"name":"oidc-client"}]}`)
+	if strings.Join(m.Requires, " ") != "route influxdb-api oidc-client" {
+		t.Fatalf("the requirements read as %v", m.Requires)
+	}
+	if m.IsOptional("route") || m.IsOptional("oidc-client") {
+		t.Error("a requirement without `optional` read as optional; hard is the default (ADR 0330 §1)")
+	}
+	if !m.IsOptional("influxdb-api") {
+		t.Error("a requirement marked optional read as hard")
+	}
+	// And written back as it was read, so a manifest through the store keeps its form.
+	raw, err := json.Marshal(m)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var again Manifest
+	if err := json.Unmarshal(raw, &again); err != nil {
+		t.Fatal(err)
+	}
+	if !again.IsOptional("influxdb-api") || again.IsOptional("route") || len(again.Requires) != 3 {
+		t.Fatalf("written and read back, it says %v optional %v (%s)", again.Requires, again.OptionalRequires, raw)
+	}
+	if strings.Contains(string(raw), `"name":`) {
+		t.Errorf("a requirement was stored in the long form: %s", raw)
+	}
+}
+
+// The stored form reads on a controller older than optional requirements (review of mesh-controller
+// #281). Inventory.Catalogue stops at the first manifest it cannot read, so a long-form entry inside
+// `requires` would have stopped every plan after a rollback. Stored, `requires` is plain names, as main's
+// manifest type reads it, and which are optional sits beside it in a key such a controller sets aside.
+func TestTheStoredFormReadsWhereRequiresIsAListOfNames(t *testing.T) {
+	m := mustParse(t, `{"module":"grafana","version":"1",
+		"requires":["route",{"name":"influxdb-api","optional":true}]}`)
+	raw, err := json.Marshal(m)
+	if err != nil {
+		t.Fatal(err)
+	}
+	// main's field, exactly: `Requires []string`.
+	var older struct {
+		Requires []string `json:"requires"`
+	}
+	if err := json.Unmarshal(raw, &older); err != nil {
+		t.Fatalf("a controller reading requires as names cannot read the stored form: %v\n%s", err, raw)
+	}
+	if strings.Join(older.Requires, " ") != "route influxdb-api" {
+		t.Fatalf("it reads the requirements as %v", older.Requires)
+	}
+	var keys map[string]json.RawMessage
+	if err := json.Unmarshal(raw, &keys); err != nil {
+		t.Fatal(err)
+	}
+	if string(keys[OptionalRequiresKey]) != `["influxdb-api"]` {
+		t.Fatalf("which are optional is stored as %s", keys[OptionalRequiresKey])
+	}
+	// And this controller reads the stored form back the same, leniently and strictly.
+	var back Manifest
+	if err := json.Unmarshal(raw, &back); err != nil {
+		t.Fatal(err)
+	}
+	strict, err := ParseManifest(raw)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, got := range []Manifest{back, strict} {
+		if !got.IsOptional("influxdb-api") || got.IsOptional("route") || len(got.Requires) != 2 {
+			t.Fatalf("read back as %v optional %v", got.Requires, got.OptionalRequires)
+		}
+	}
+	// A stored list naming something the module does not require is refused.
+	if _, err := ParseManifest([]byte(`{"module":"x","version":"1","requires":["route"],"optional-requires":["mqtt-topic"]}`)); err == nil {
+		t.Error("an optional requirement the module does not require passed the check")
+	}
+}
+
+func TestARequirementsLongFormRefusesWhatItDoesNotKnow(t *testing.T) {
+	for _, raw := range []string{
+		`{"module":"x","version":"1","requires":[{"name":"influxdb-api","optinal":true}]}`,
+		`{"module":"x","version":"1","requires":[{"optional":true}]}`,
+	} {
+		if _, err := ParseManifest([]byte(raw)); err == nil {
+			t.Errorf("accepted %s", raw)
+		}
+	}
+}
+
+func TestAnOptionalRequirementWithNoProviderIsAbsentAndNothingIsInstalled(t *testing.T) {
+	// Exactly one catalogue module could answer each — the case where a hard requirement installs it.
+	// Brokered (influxdb-api, from anywhere) and on this machine (shell); both passes.
+	for _, world := range []World{{}, {Unchecked: true}} {
+		got, err := Resolve(optionalShelf(), []string{"grafana"}, reachable(), world)
+		if err != nil {
+			t.Fatalf("an optional requirement with no provider refused the assignment: %v", err)
+		}
+		if have := strings.Join(names(got), " "); have != "grafana" {
+			t.Fatalf("assigning grafana put %s on the machine; nothing is installed for an optional requirement (ADR 0330 §3)", have)
+		}
+		if world.Unchecked {
+			continue
+		}
+		want := []Absent{{Consumer: "grafana", Requirement: "influxdb-api"}, {Consumer: "grafana", Requirement: "shell"}}
+		if len(got.Absent) != 2 || got.Absent[0] != want[0] || got.Absent[1] != want[1] {
+			t.Fatalf("absent: %+v, want %+v", got.Absent, want)
+		}
+		if len(got.Needs) != 0 {
+			t.Fatalf("an absent requirement was given a binding: %+v", got.Needs)
+		}
+	}
+}
+
+func TestAnOptionalRequirementWithAProviderBindsAsAHardOne(t *testing.T) {
+	world := World{Offered: map[string][]Provider{"influxdb-api": {
+		{Node: "anchor", At: "anchor.internal", Module: "influxdb", Serves: map[string]any{"port": 8086}}}}}
+	got, err := Resolve(optionalShelf(), []string{"grafana", "zsh"}, reachable(), world)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if n := boundFrom(t, got, "grafana", "influxdb-api"); n.From != "anchor" || n.Module != "influxdb" {
+		t.Fatalf("bound to %s/%s", n.From, n.Module)
+	}
+	if len(got.Absent) != 0 {
+		t.Fatalf("a requirement with a provider was left absent: %+v", got.Absent)
+	}
+	// And the same assignment without the provider is absent: what binds it later is only the
+	// provider being assigned, with no act on grafana (ADR 0330 §7).
+	before, err := Resolve(optionalShelf(), []string{"grafana", "zsh"}, reachable(), World{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(before.Absent) != 1 || before.Absent[0].Requirement != "influxdb-api" {
+		t.Fatalf("absent before the provider was assigned: %+v", before.Absent)
+	}
+}
+
+func TestOneConsumersOptionalRequirementIsAnothersHardOne(t *testing.T) {
+	// telegraf wants influxdb-api hard: with nothing offering it, the assignment is refused as
+	// before, naming what to assign — grafana's optional does not soften telegraf's.
+	_, err := Resolve(optionalShelf(), []string{"grafana", "telegraf"}, reachable(), World{})
+	if err == nil || !strings.Contains(err.Error(), "assign influxdb") {
+		t.Fatalf("a hard requirement with no provider was not refused naming the candidate: %v", err)
+	}
+	// And the refusal names telegraf, whose remedy it is, not grafana, which met the name first.
+	if !strings.Contains(err.Error(), "wanted by telegraf") {
+		t.Errorf("the refusal does not name the module that wants it hard: %v", err)
+	}
+	// And a module pulled in later (suite → editor) that wants the shell hard installs it, even
+	// though grafana, met first, wanted it only optionally — and grafana is then bound to it.
+	got, err := Resolve(optionalShelf(), []string{"grafana", "suite"}, workstation(), World{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if have := strings.Join(names(got), " "); !strings.Contains(have, "zsh") {
+		t.Fatalf("a hard requirement met after an optional one was not installed: %s", have)
+	}
+	for _, a := range got.Absent {
+		if a.Requirement == "shell" {
+			t.Fatalf("the shell is installed and still listed absent: %+v", got.Absent)
+		}
+	}
+}
+
+func TestAHardRequirementWithNoProviderIsStillRefused(t *testing.T) {
+	_, err := Resolve(optionalShelf(), []string{"telegraf"}, reachable(), World{})
+	if err == nil || !strings.Contains(err.Error(), "influxdb") {
+		t.Fatalf("got %v", err)
+	}
+}
+
+func optionalModule(resources string) string {
+	return `{"module":"grafana","version":"1",
+		"requires":["route",{"name":"influxdb-api","optional":true}],
+		"secrets":{"influxdb-api":"/var/lib/grafana/influxdb-api"},
+		"resources":[` + resources + `]}`
+}
+
+func TestTheModuleCheckRefusesAnOptionalPlaceholderThatCouldRenderEmpty(t *testing.T) {
+	refused := map[string]string{
+		"a placeholder without a default": `{"id":"ds","type":"file","path":"/a","mode":"0644",
+			"content":"url: ${bound:influxdb-api:at}"}`,
+		"a secret outside an only-when-bound file": `{"id":"s","type":"file","path":"/a","mode":"0400",
+			"content":"${secret:influxdb-api}"}`,
+		"only-when-bound on a hard requirement": `{"id":"r","type":"file","path":"/a","mode":"0644",
+			"content":"x","only-when-bound":"route"}`,
+		"only-when-bound on something not required": `{"id":"r","type":"file","path":"/a","mode":"0644",
+			"content":"x","only-when-bound":"mqtt-topic"}`,
+		"only-when-bound on a directory": `{"id":"d","type":"directory","mode":"0700",
+			"only-when-bound":"influxdb-api"}`,
+		"a default on a hard requirement": `{"id":"r","type":"file","path":"/a","mode":"0644",
+			"content":"${bound:route:name|default:x}"}`,
+	}
+	for what, resource := range refused {
+		if _, err := ParseManifest([]byte(optionalModule(resource))); err == nil {
+			t.Errorf("%s passed the module check", what)
+		} else if what == "a placeholder without a default" && !strings.Contains(err.Error(), "|default:") {
+			t.Errorf("the refusal does not say how to write it: %v", err)
+		}
+	}
+	accepted := map[string]string{
+		"a placeholder with a default": `{"id":"ds","type":"file","path":"/a","mode":"0644",
+			"content":"url: ${bound:influxdb-api:at|default:none}"}`,
+		"a placeholder and a secret inside an only-when-bound file": `{"id":"ds","type":"file","path":"/a",
+			"mode":"0400","content":"url: ${bound:influxdb-api:at}\npassword: ${secret:influxdb-api}",
+			"only-when-bound":"influxdb-api"}`,
+	}
+	for what, resource := range accepted {
+		if _, err := ParseManifest([]byte(optionalModule(resource))); err != nil {
+			t.Errorf("%s was refused: %v", what, err)
+		}
+	}
+}
+
+func absentGrafana(t *testing.T, absent bool) Resolution {
+	t.Helper()
+	m := mustParse(t, optionalModule(`
+		{"id":"env","type":"file","path":"/var/lib/grafana/env","mode":"0644",
+		 "content":"INFLUX=${bound:influxdb-api:at|default:none}:${bound:influxdb-api:port|default:0}\n"},
+		{"id":"ds","type":"file","path":"/var/lib/grafana/ds.yaml","mode":"0400",
+		 "content":"url: ${bound:influxdb-api:at}\npassword: ${secret:influxdb-api}\n","only-when-bound":"influxdb-api"}`))
+	m.Requires = []string{"influxdb-api"}
+	m.Binds = map[string]string{"influxdb-api": "/var/lib/grafana/influxdb.json"}
+	r := Resolution{Node: "workstation", Modules: []Manifest{m}}
+	if absent {
+		r.Absent = []Absent{{Consumer: "grafana", Requirement: "influxdb-api"}}
+	} else {
+		r.Needs = []Needed{{Name: "influxdb-api", From: "anchor", At: "anchor.internal", For: "grafana",
+			Module: "influxdb", Sealed: "sealed-influx", Serves: map[string]any{"port": float64(8086)}}}
+	}
+	return r
+}
+
+func TestAnAbsentRequirementIsComposedWithItsDefaultsAndWithoutItsFiles(t *testing.T) {
+	out, err := absentGrafana(t, true).Declaration(Rendering{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	env := fileNamed(out, "grafana.env")
+	if env == nil || env["content"] != "INFLUX=none:0\n" {
+		t.Fatalf("the defaults were not rendered: %v", env)
+	}
+	for _, id := range []string{"grafana.ds", "grafana." + SecretID("influxdb-api"), "grafana." + BoundID("influxdb-api")} {
+		if fileNamed(out, id) != nil {
+			t.Errorf("%s was delivered while influxdb-api is absent (ADR 0330 §5, §6)", id)
+		}
+	}
+	for _, r := range out {
+		if _, has := r[OnlyWhenBound]; has {
+			t.Errorf("%v carries %s to the node-engine, which knows no such field", r["id"], OnlyWhenBound)
+		}
+	}
+}
+
+func TestABoundOptionalRequirementIsComposedAsAHardOne(t *testing.T) {
+	out, err := absentGrafana(t, false).Declaration(Rendering{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if env := fileNamed(out, "grafana.env"); env == nil || env["content"] != "INFLUX=anchor.internal:8086\n" {
+		t.Fatalf("the bound values were not rendered: %v", env)
+	}
+	ds := fileNamed(out, "grafana.ds")
+	if ds == nil {
+		t.Fatalf("the only-when-bound file was left out while bound: %v", out)
+	}
+	if _, has := ds[OnlyWhenBound]; has {
+		t.Errorf("the file carries %s to the node-engine", OnlyWhenBound)
+	}
+	for _, id := range []string{"grafana." + SecretID("influxdb-api"), "grafana." + BoundID("influxdb-api")} {
+		if fileNamed(out, id) == nil {
+			t.Errorf("%s was not delivered while bound", id)
+		}
+	}
+}

internal/catalogue/outside_not_given_test.go

@@ -0,0 +1,106 @@
+package catalogue
+
+import (
+	"strings"
+	"testing"
+)
+
+// An own secret issued outside the mesh that nobody gave (novox/hq issue 401, ADR 0228): the mesh makes no value for it,
+// so the composition places no file, a file of the module that names it says empty there, and nothing restarts on it.
+// Given, it is placed and filled like any own secret.
+
+func outsideManifest(t *testing.T) Manifest {
+	t.Helper()
+	m, err := ParseManifest([]byte(`{"module":"assistant","version":"1",
+	  "own-secrets":{
+	    "password":{"path":"/var/lib/assistant/password.secret","taken":"at-start"},
+	    "vendor-key":{"path":"/var/lib/assistant/vendor-key.secret","taken":"at-start","issued-by":"outside"}},
+	  "resources":[
+	    {"id":"env","type":"file","path":"/var/lib/assistant/env","mode":"0600",
+	     "content":"PASSWORD=${secret:password}\nVENDOR_KEY=${secret:vendor-key}\n"},
+	    {"id":"server","type":"container","name":"assistant","image":"assistant:1",
+	     "env-file":["/var/lib/assistant/env"],
+	     "volumes":["/var/lib/assistant/vendor-key.secret:/run/vendor-key:ro"],
+	     "secrets-in-environment":"reads its settings from the environment only"}]}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	return m
+}
+
+func resourceAt(out []map[string]any, path string) map[string]any {
+	for _, r := range out {
+		if r["path"] == path {
+			return r
+		}
+	}
+	return nil
+}
+
+func resourceNamed(out []map[string]any, name string) map[string]any {
+	for _, r := range out {
+		if r["name"] == name {
+			return r
+		}
+	}
+	return nil
+}
+
+func TestAnOutsideSecretNotGivenIsNoFileAndAFileNamingItSaysEmpty(t *testing.T) {
+	r := Resolution{Node: "server", Modules: []Manifest{outsideManifest(t)}}
+	out, err := r.Declaration(Rendering{Needed: map[string]map[string]string{"assistant": {"password": "sealed-password"}}})
+	if err != nil {
+		t.Fatalf("a module whose outside secret nobody gave did not compose: %v", err)
+	}
+	if got := resourceAt(out, "/var/lib/assistant/vendor-key.secret"); got != nil {
+		t.Fatalf("a secret nobody gave was placed: %v", got)
+	}
+	env := resourceAt(out, "/var/lib/assistant/env")
+	if env == nil {
+		t.Fatal("the module's own file is not composed")
+	}
+	if content := env["content"].(string); content != "PASSWORD=${secret:password}\nVENDOR_KEY=\n" {
+		t.Fatalf("the file names the secret nobody gave as %q", content)
+	}
+	secrets, _ := env["secrets"].(map[string]any)
+	if len(secrets) != 1 || secrets["password"] != "sealed-password" {
+		t.Fatalf("the file is filled from %v", secrets)
+	}
+	server := resourceNamed(out, "assistant")
+	if on := strings.Join(stringsIn(server["restart-on"]), " "); strings.Contains(on, "vendor-key") {
+		t.Fatalf("the container restarts on a secret nobody gave: %q", on)
+	}
+}
+
+func TestAnOutsideSecretGivenIsPlacedAndFilled(t *testing.T) {
+	r := Resolution{Node: "server", Modules: []Manifest{outsideManifest(t)}}
+	out, err := r.Declaration(Rendering{Needed: map[string]map[string]string{"assistant": {
+		"password": "sealed-password", "vendor-key": "sealed-vendor-key"}}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	placed := resourceAt(out, "/var/lib/assistant/vendor-key.secret")
+	if placed == nil || placed["sealed"] != "sealed-vendor-key" {
+		t.Fatalf("the secret given is placed as %v", placed)
+	}
+	env := resourceAt(out, "/var/lib/assistant/env")
+	if content := env["content"].(string); content != "PASSWORD=${secret:password}\nVENDOR_KEY=${secret:vendor-key}\n" {
+		t.Fatalf("the file was changed: %q", content)
+	}
+	if secrets, _ := env["secrets"].(map[string]any); secrets["vendor-key"] != "sealed-vendor-key" {
+		t.Fatalf("the file is filled from %v", secrets)
+	}
+	server := resourceNamed(out, "assistant")
+	if on := strings.Join(stringsIn(server["restart-on"]), " "); !strings.Contains(on, "assistant."+NeedID("vendor-key")) {
+		t.Fatalf("the container does not restart on the secret given: %q", on)
+	}
+}
+
+// A secret the mesh makes is still refused when it was not made: only an outside one is left out.
+func TestAnOwnSecretTheMeshMakesIsStillRefusedWhenNotMade(t *testing.T) {
+	r := Resolution{Node: "server", Modules: []Manifest{outsideManifest(t)}}
+	_, err := r.Declaration(Rendering{})
+	if nm, ok := err.(*NotMadeError); !ok || nm.Name != "password" {
+		t.Fatalf("a secret the mesh makes, not made: %v", err)
+	}
+}

internal/catalogue/reads.go

@@ -0,0 +1,220 @@
+package catalogue
+
+import (
+	"encoding/json"
+	"fmt"
+	"path/filepath"
+	"sort"
+	"strings"
+)
+
+// A node's files and accounts, read (novox/hq ADR 0310, extending ADR 0268 §5; hq to-be 41 WP8).
+//
+// **A seat of its own on every node.** Reading a file, searching one, listing a directory, the owner and mode
+// of each component of a path, and looking up an account or a group are the reads ADR 0268 §5 has narrow tools
+// take over from the login shell's `execute`, so an approval is asked for an act and never for a read. Every
+// node needs them, the control-node included, and another module could offer them instead of the tool
+// runner's (ADR 0126 §9): a seat, so the mesh finds them on every node by one name.
+//
+// **Read as an account that holds no secret.** The holder runs as an account of its own (runs-as, ADR 0259
+// §8), so the node's file modes bound what it sees — never the operator's account, which sees the
+// operator's keys and the agent's credentials. On top, it refuses by name the places a secret is kept,
+// which the controller names for it (secretPlaces), and every answer passes the content rule's secret class
+// (mesh-sdk's outward, ADR 0310 §4).
+
+// ReadsSeat is the role that reads a node's files and accounts (novox/hq ADR 0310).
+const ReadsSeat = "node-reads"
+
+// ReadsSecretPlaces is the word the holder of node-reads is given: the places on its node where a secret is
+// kept, as a JSON list of absolute paths, each refused by name before any read (novox/hq ADR 0310 §5).
+const ReadsSecretPlaces = "MESH_SECRET_PLACES"
+
+// readsVerbs is the contract every holder of node-reads serves (novox/hq ADR 0310 §2). The bounds are the
+// build's to set and each verb's description to state (ADR 0310, Consequences); the holder states them in
+// every answer it cuts.
+func readsVerbs() []Verb {
+	return []Verb{
+		{Name: "stat", Description: "Each component of one path or several, from / down: its type, owner and group " +
+			"(name and number), mode, whether it is a link and to what, and whether it is a mount point and of which " +
+			"file system. A link is not followed unless follow is \"true\". Read as the holder's own account, which " +
+			"holds no secret: a component it may not reach says so. At most 200 paths in one call.",
+			Input: schema(map[string]string{
+				"paths":  "one absolute path, or several separated by line breaks",
+				"follow": "\"true\": also say where the path leads once every link is followed",
+			}, []string{"paths"}, "follow"),
+			Replaces: []string{"stat", "ls -ld", "namei -l", "findmnt -T"}},
+		{Name: "readlink", Description: "What one link points to, as written, and where the path leads once every " +
+			"link is followed, and whether that exists.",
+			Input:    schema(map[string]string{"path": "an absolute path"}, []string{"path"}),
+			Replaces: []string{"readlink", "readlink -f", "realpath"}},
+		{Name: "list", Description: "Every entry of one directory with its type, owner, group, mode, size and, for a " +
+			"link, its target. At most 2000 entries; a longer directory is cut and says so. A place a secret is kept " +
+			"is refused by name.",
+			Input:    schema(map[string]string{"path": "an absolute path to a directory"}, []string{"path"}),
+			Replaces: []string{"ls", "ls -la"}},
+		{Name: "read", Description: "One text file, or a part of it by line: at most 256 KiB in one answer " +
+			"(64 KiB unless more is asked), cut at a line and said so. A binary file is refused; a place a secret is " +
+			"kept, or a known credential file, is refused by name; a line shaped like a secret is withheld and its " +
+			"number said. /proc and /sys are read as far as the holder's account may.",
+			Input: schema(map[string]string{
+				"path":  "an absolute path to a file",
+				"from":  "the first line to answer, counted from 1 (optional)",
+				"lines": "how many lines to answer (optional)",
+				"bytes": "the most bytes to answer, up to 262144 (optional, 65536 unless given)",
+			}, []string{"path"}),
+			Replaces: []string{"cat", "head", "tail", "less"}},
+		{Name: "search", Description: "Find a fixed string (never a pattern) in one file or under one directory: " +
+			"every matching line with its file and number. Bounded: at most 500 matches (100 unless more is asked), " +
+			"8 directories deep (4 unless more is asked), 5000 files and 4 MiB per file; links are not followed and " +
+			"binary files are skipped. A place a secret is kept is skipped and named; a matching line shaped like a " +
+			"secret is withheld. The answer says which bound it met.",
+			Input: schema(map[string]string{
+				"text":    "the fixed string to find",
+				"path":    "an absolute path to a file or a directory",
+				"depth":   "how many directories deep, up to 8 (optional)",
+				"matches": "the most matches to answer, up to 500 (optional)",
+				"case":    "\"false\": match whatever the case (optional)",
+			}, []string{"text", "path"}, "case"),
+			Replaces: []string{"grep", "grep -r", "grep -F"}},
+		{Name: "account", Description: "One account or group by name or number, as this node's account files say: " +
+			"an account's number, group, home, shell and every group it is in; a group's number and members. With " +
+			"neither, every account and group. Never a password field.",
+			Input: schema(map[string]string{
+				"name":  "an account's name or number (optional)",
+				"group": "a group's name or number (optional)",
+			}, nil),
+			Replaces: []string{"getent passwd", "getent group", "id", "groups"}},
+	}
+}
+
+// ReadsHolderProblems is what a holder of node-reads is held to (novox/hq ADR 0310 §3): it reads as an
+// account of its own, so the node's file modes bound what it sees. Carried by the machine's runtime it would
+// read as the operator's account, which sees the operator's keys and the agent's credentials.
+func ReadsHolderProblems(m Manifest) []string {
+	if !m.ClaimsSeat(ReadsSeat) {
+		return nil
+	}
+	if m.RunsAs == "" {
+		return []string{fmt.Sprintf("%s claims %s and must run as an account of its own (runs-as): its reads are "+
+			"bounded by that account's file modes, and the machine's runtime runs as the operator's account "+
+			"(novox/hq ADR 0310 §3)", m.Module, ReadsSeat)}
+	}
+	// In no group beside its own: a group is a way to a secret (docker's is root's), and the account's file modes
+	// are what bound its reads.
+	for _, r := range m.Resources {
+		if fmt.Sprint(r["type"]) != "user" || fmt.Sprint(r["name"]) != m.RunsAs {
+			continue
+		}
+		if groups, said := r["groups"]; said {
+			if list, ok := groups.([]any); !ok || len(list) > 0 {
+				return []string{fmt.Sprintf("%s claims %s, and its account %s is put in groups %v: the account that "+
+					"reads is in no group beside its own (novox/hq ADR 0310 §3)", m.Module, ReadsSeat, m.RunsAs, groups)}
+			}
+		}
+	}
+	return nil
+}
+
+// secretPlaces is every place on this node a secret is kept, as the placed manifests say (novox/hq ADR 0310
+// §5): the directory of every module's own secret, every credential file a module is given and every grant
+// directory a provider is handed its consumers' credentials in, the place a module keeps the operator-sealed
+// secrets, and every directory of the module that provides `secret` — the vault — wherever the node places it,
+// a directory declared without a path included. Sorted, each once, and a place under another dropped, so the
+// list says each refusal once.
+//
+// **Failure is loud.** A place still holding a placeholder, or not absolute, fails the composition with the
+// module named: a list that silently shrank would be a refusal the decision promises and nothing does.
+func (r Resolution) secretPlaces(with Rendering) ([]string, error) {
+	seen := map[string]bool{}
+	var problems []string
+	add := func(module, what, path string) {
+		path = strings.TrimSpace(path)
+		if path == "" {
+			return
+		}
+		if !strings.HasPrefix(path, "/") || strings.Contains(path, "${") {
+			problems = append(problems, fmt.Sprintf("%s's %s is %q, which is not a place on %s", module, what, path, r.Node))
+			return
+		}
+		path = filepath.Clean(path)
+		if path == "/" {
+			problems = append(problems, fmt.Sprintf("%s's %s is the root directory", module, what))
+			return
+		}
+		seen[path] = true
+	}
+	for _, m := range r.Modules {
+		for name, own := range m.OwnSecrets {
+			add(m.Module, "own secret "+name, own.Path)
+			if strings.HasPrefix(own.Path, "/") {
+				add(m.Module, "own secret "+name+"'s directory", filepath.Dir(own.Path))
+			}
+		}
+		for _, to := range m.SecretRequirements() {
+			for _, f := range m.SecretFiles(to) {
+				add(m.Module, "credential file for "+to, f.Path)
+			}
+		}
+		for to, where := range m.Grants {
+			add(m.Module, "grant directory for "+to, where)
+		}
+		add(m.Module, "place for the operator-sealed secrets (keeps)", m.Keeps)
+		if providesSecret(m) {
+			dirs := dirsFor(m, with)
+			for _, id := range sortedKeys(dirs) {
+				add(m.Module, "directory "+id, dirs[id])
+			}
+		}
+	}
+	if len(problems) > 0 {
+		sort.Strings(problems)
+		return nil, fmt.Errorf("the holder of %s on %s cannot be told where a secret is kept, so it would read "+
+			"one (novox/hq ADR 0310 §5): %s", ReadsSeat, r.Node, strings.Join(problems, "; "))
+	}
+	all := make([]string, 0, len(seen))
+	for p := range seen {
+		all = append(all, p)
+	}
+	sort.Strings(all)
+	var out []string
+	for _, p := range all {
+		if n := len(out); n > 0 && strings.HasPrefix(p, out[n-1]+"/") {
+			continue
+		}
+		out = append(out, p)
+	}
+	return out, nil
+}
+
+func providesSecret(m Manifest) bool {
+	for _, p := range m.Provides {
+		if p.Name == "secret" {
+			return true
+		}
+	}
+	return false
+}
+
+// readsWords is what the holder of node-reads is given beside its own words: the node's secret places.
+func (r Resolution) readsWords(m Manifest, words map[string]string, with Rendering) (map[string]string, error) {
+	if !m.ClaimsSeat(ReadsSeat) {
+		return words, nil
+	}
+	places, err := r.secretPlaces(with)
+	if err != nil {
+		return nil, err
+	}
+	body, err := json.Marshal(places)
+	if err != nil {
+		return nil, err
+	}
+	if words == nil {
+		words = map[string]string{}
+	}
+	if _, has := words[ReadsSecretPlaces]; has {
+		return nil, fmt.Errorf("%s gives its own %s; the node's secret places are the mesh's to say (novox/hq ADR 0310 §5)",
+			m.Module, ReadsSecretPlaces)
+	}
+	words[ReadsSecretPlaces] = string(body)
+	return words, nil
+}

internal/catalogue/reads_test.go

@@ -0,0 +1,136 @@
+package catalogue
+
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+)
+
+// novox/hq ADR 0310 §1, §2: node-reads is a node seat, and its verbs say the commands they replace, so
+// mesh_search finds them by `cat`, `grep` and `getent passwd` (ADR 0245 §3).
+func TestNodeReadsIsANodeSeatWhoseVerbsSayWhatTheyReplace(t *testing.T) {
+	s, ok := SeatNamed(ReadsSeat)
+	if !ok {
+		t.Fatalf("the mesh defines no seat %s", ReadsSeat)
+	}
+	if s.Scope != ScopeNode || s.Delivers != "" || !strings.Contains(s.Decision, "0310") {
+		t.Errorf("%s: scope %q, delivers %q, decision %q", ReadsSeat, s.Scope, s.Delivers, s.Decision)
+	}
+	replaced := map[string]string{}
+	for _, v := range s.Serves {
+		if v.Optional {
+			t.Errorf("%s.%s is optional: a new seat's holder serves every verb", ReadsSeat, v.Name)
+		}
+		if len(v.Replaces) == 0 {
+			t.Errorf("%s.%s says nothing it replaces", ReadsSeat, v.Name)
+		}
+		for _, c := range v.Replaces {
+			replaced[c] = v.Name
+		}
+	}
+	for command, verb := range map[string]string{"cat": "read", "grep": "search", "getent passwd": "account",
+		"getent group": "account", "id": "account", "stat": "stat", "readlink": "readlink", "ls": "list"} {
+		if replaced[command] != verb {
+			t.Errorf("%q is replaced by %q, want %s.%s", command, replaced[command], ReadsSeat, verb)
+		}
+	}
+}
+
+// novox/hq ADR 0310 §3: a holder of node-reads reads as an account of its own; one the machine's runtime would
+// carry — as the operator's account — is refused at parse.
+func TestAHolderOfNodeReadsWithoutAnAccountOfItsOwnIsRefused(t *testing.T) {
+	_, err := ParseManifest([]byte(`{"module": "reads", "version": "1",
+		"claims": [{"name": "node-reads", "scope": "node"}]}`))
+	if err == nil || !strings.Contains(err.Error(), "runs-as") || !strings.Contains(err.Error(), "0310") {
+		t.Errorf("a holder of node-reads without runs-as was not refused for it: %v", err)
+	}
+	if p := ReadsHolderProblems(Manifest{Module: "reads", RunsAs: "mesh-reads",
+		Claims: []Claim{{Name: ReadsSeat}}}); len(p) != 0 {
+		t.Errorf("a holder running as its own account was refused: %v", p)
+	}
+}
+
+// novox/hq ADR 0310 §5: the holder is told, by the composition, where its node keeps a secret — the directory
+// of every module's own secret, every credential file and grant directory, the vault's directories and the
+// place the operator-sealed secrets are kept — and no other module is told.
+func TestTheHolderOfNodeReadsIsToldWhereItsNodeKeepsASecret(t *testing.T) {
+	with := Rendering{ArtifactStore: "anchor.internal:5101",
+		Needed: map[string]map[string]string{RuntimeModule: {"broker": "sealed-credential"},
+			"reads": {"broker": "own"}, "desk": {"broker": "own"}}}
+	goRuntime := Manifest{Module: RuntimeModule, Version: "1",
+		OwnSecrets: OwnSecrets{"broker": {Path: "/var/lib/mesh/" + RuntimeModule + "/broker"}},
+		Build: &Build{Artifacts: []Artifact{{Name: "runtime", Kind: ArtifactBundle, Language: "go",
+			System: "arch", From: "cmd/node-tools"}}}}
+	goRuntime, err := goRuntime.Resolve([]Built{{Name: "runtime", Kind: ArtifactBundle,
+		Reference: ArtifactStoreScheme + RuntimeModule + "/runtime/blobs/" + bundleDigest, Digest: bundleDigest}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	reads := aToolsModule(t, "reads", "tools/index.js")
+	reads.RunsAs, reads.SecretsOwner = "mesh-reads", "mesh-reads"
+	reads.Claims = []Claim{{Name: ReadsSeat}}
+	reads.OwnSecrets = OwnSecrets{"broker": {Path: "/var/lib/mesh-reads/broker"}}
+	desk := aToolsModule(t, "desk", "tools/index.js")
+	desk.RunsAs, desk.SecretsOwner = "desk", "desk"
+	desk.OwnSecrets = OwnSecrets{"broker": {Path: "/var/lib/desk/broker"}}
+	// The vault as the catalogue declares it: its directories have no path of their own, and the node places them.
+	vault, err := placedManifest(catalogueManifest(t, "mesh-vault"), with)
+	if err != nil {
+		t.Fatal(err)
+	}
+	app := Manifest{Module: "app", Version: "1", Secrets: map[string]string{"postgres-database": "/etc/app/db.secret"},
+		OwnSecrets: OwnSecrets{"token": {Path: "/home/ops/.config/app/token"}}}
+	r := Resolution{Node: "anchor", Account: "ops", Modules: []Manifest{reads, desk, vault, app, goRuntime}}
+	owns, err := r.ownRuntimes(with)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var given map[string]map[string]string
+	for _, p := range owns {
+		if p["id"] == "reads."+OwnRuntimeID() {
+			if err := json.Unmarshal([]byte(p["env"].(map[string]string)[RuntimeToolEnv]), &given); err != nil {
+				t.Fatal(err)
+			}
+		}
+		if p["id"] == "desk."+OwnRuntimeID() && strings.Contains(p["env"].(map[string]string)[RuntimeToolEnv], ReadsSecretPlaces) {
+			t.Error("a module not holding node-reads is told the node's secret places")
+		}
+	}
+	var places []string
+	if err := json.Unmarshal([]byte(given["reads"][ReadsSecretPlaces]), &places); err != nil {
+		t.Fatalf("the holder is not told its node's secret places: %v (%v)", err, given)
+	}
+	want := []string{"/etc/app/db.secret", "/home/ops/.config/app", "/var/lib/desk", "/var/lib/mesh-reads",
+		"/var/lib/mesh-vault", "/var/lib/mesh/" + RuntimeModule}
+	if strings.Join(places, " ") != strings.Join(want, " ") {
+		t.Errorf("secret places:\n got %v\nwant %v", places, want)
+	}
+}
+
+// The review of #257: a secret place the controller cannot resolve fails the composition, naming the module,
+// rather than leaving the list one place shorter.
+func TestASecretPlaceThatCannotBeResolvedFailsTheComposition(t *testing.T) {
+	r := Resolution{Node: "anchor", Modules: []Manifest{
+		{Module: "app", Version: "1", Keeps: "${dir:keep}/sealed"},
+	}}
+	if _, err := r.secretPlaces(Rendering{}); err == nil || !strings.Contains(err.Error(), "app") {
+		t.Errorf("an unresolved place was dropped: %v", err)
+	}
+	r.Modules[0].Keeps = "relative/place"
+	if _, err := r.secretPlaces(Rendering{}); err == nil {
+		t.Error("a relative place was dropped")
+	}
+}
+
+// ADR 0310 §3: the account that reads is in no group beside its own; one put in a group is refused.
+func TestTheReadsAccountIsInNoGroup(t *testing.T) {
+	m := Manifest{Module: "reads", RunsAs: "mesh-reads", Claims: []Claim{{Name: ReadsSeat}},
+		Resources: []map[string]any{{"id": "account", "type": "user", "name": "mesh-reads", "groups": []any{"docker"}}}}
+	if p := ReadsHolderProblems(m); len(p) != 1 || !strings.Contains(p[0], "docker") {
+		t.Errorf("an account in docker was not refused: %v", p)
+	}
+	m.Resources[0]["groups"] = []any{}
+	if p := ReadsHolderProblems(m); len(p) != 0 {
+		t.Errorf("an account in no group was refused: %v", p)
+	}
+}

internal/catalogue/resolve.go

@@ -183,6 +183,10 @@ type Resolution struct {
 	// that keeps its data, and did not (novox/hq ADR 0232): it stays bound where its data is, and the
 	// controller raises an urgent condition naming the move until a person pins one or the other.
 	Kept []KeptBinding
+	// Absent is every optional requirement of this node's modules that nothing assigned answers
+	// (novox/hq ADR 0330 §3): left unbound rather than refused, with nothing installed for it, and
+	// listed by `plan` and `node` (§7). It binds on the first composition after a provider is assigned.
+	Absent []Absent
 }
 
 // Unhostable is one directly-assigned module the machine cannot run.
@@ -374,12 +378,80 @@ func Resolve(catalogue map[string]Manifest, assigned []string, node Node, world
 	// identical lines before realising there is none.
 	reported := map[string]bool{}
 
-	for len(queue) > 0 {
+	// **An optional requirement is settled last** (novox/hq ADR 0330). Whether a name is optional is
+	// a question about every module that wants it, and a module pulled in later may want it hard; so
+	// a name only optional modules want so far is put aside until the walk has nothing else, and only
+	// then, if still nobody wants it hard, settled by the optional rule: bound to a provider that is
+	// already assigned or reachable, exactly as a hard one, and otherwise absent — never refused,
+	// and never answered by installing anything.
+	var deferred []string
+	settling := map[string]bool{}
+	absent := map[string]bool{}
+	wantedHard := func(want string) bool {
+		for _, name := range order {
+			if catalogue[name].wantsHard(want) {
+				return true
+			}
+		}
+		return false
+	}
+	wantedOptionally := func(want string) bool {
+		for _, name := range order {
+			if catalogue[name].IsOptional(want) {
+				return true
+			}
+		}
+		return false
+	}
+	leaveAbsent := func(want string) {
+		absent[want] = true
+		reported[want] = true
+	}
+
+	for {
+		if len(queue) == 0 {
+			if len(deferred) == 0 {
+				break
+			}
+			// What a module chosen since wants hard goes back to the walk, which may install for
+			// it; only when none does is the rest settled, since settling installs nothing and so
+			// can change no other name's answer.
+			var hard, optional []string
+			for _, d := range deferred {
+				if wantedHard(d) {
+					hard = append(hard, d)
+				} else {
+					optional = append(optional, d)
+				}
+			}
+			if len(hard) > 0 {
+				queue, deferred = hard, optional
+				continue
+			}
+			for _, d := range optional {
+				settling[d] = true
+			}
+			queue, deferred = optional, nil
+		}
 		want := queue[0]
 		queue = queue[1:]
 		if chosen[want] || reported[want] {
 			continue
 		}
+		if !settling[want] && because[want] != "assigned" && !wantedHard(want) && wantedOptionally(want) {
+			deferred = append(deferred, want)
+			continue
+		}
+		// Walked as a hard requirement: a refusal names a module that wants it hard, never one that
+		// wanted it only optionally and met it first — whose remedy it is not.
+		if first, known := catalogue[because[want]]; !settling[want] && known && !first.wantsHard(want) {
+			for _, name := range order {
+				if catalogue[name].wantsHard(want) {
+					because[want] = name
+					break
+				}
+			}
+		}
 		// Already answered by something in the set. This is the case that makes assigning zsh do
 		// what a person meant by it.
 		//
@@ -483,6 +555,12 @@ func Resolve(catalogue map[string]Manifest, assigned []string, node Node, world
 		if brokered[want] {
 			reported[want] = true
 			where := world.Offered[want]
+			if settling[want] && len(where) == 0 {
+				// Nothing assigned anywhere answers it: absent, and nothing is put on a machine
+				// for it (ADR 0330 §3), however few modules in the catalogue could.
+				leaveAbsent(want)
+				continue
+			}
 			names := providerNames(where)
 			take := func(p Provider) {
 				if node.At != "" && p.At == "" || node.At == "" && p.At != "" || node.At == "" && p.At == "" {
@@ -579,6 +657,10 @@ func Resolve(catalogue map[string]Manifest, assigned []string, node Node, world
 		// research 026 found. Another node's provider never counts — node scope is never brokered.
 		if machineReach[want] && !isModule(catalogue, want) {
 			reported[want] = true
+			if settling[want] {
+				leaveAbsent(want)
+				continue
+			}
 			if world.Unchecked {
 				// The first pass's refusals take a machine off the network; the second says it.
 				continue
@@ -591,6 +673,13 @@ func Resolve(catalogue map[string]Manifest, assigned []string, node Node, world
 		}
 
 		candidates := offers[want]
+		if settling[want] && !(len(candidates) == 0 && len(world.Licences[want]) > 0) {
+			// Not answered by anything in this node's set, and only installing could answer it
+			// here — which is never done for an optional requirement (ADR 0330 §3), not even
+			// for the only candidate. A licence record still answers it, in the post-pass.
+			leaveAbsent(want)
+			continue
+		}
 		switch len(candidates) {
 		case 0:
 			if len(world.Licences[want]) > 0 {
@@ -724,7 +813,8 @@ func Resolve(catalogue map[string]Manifest, assigned []string, node Node, world
 	resolution := Resolution{Node: node.Name, At: node.At, PublicDomain: node.PublicDomain,
 		Account: node.Account, AccountHome: node.AccountHome, AgentAccount: node.AgentAccount,
 		AgentAccountHome: node.AgentAccountHome, Capabilities: node.Capabilities,
-		Because: because, Needs: needs, Unhostable: unhostable, Kept: kept}
+		Because: because, Needs: needs, Unhostable: unhostable, Kept: kept,
+		Absent: absentOf(absent, order, catalogue)}
 	for _, n := range providersFirst(order, catalogue) {
 		resolution.Modules = append(resolution.Modules, catalogue[n])
 	}
@@ -957,7 +1047,9 @@ func checkResources(modules []Manifest) []string {
 	// Judged as the machine composes them: where the node-resolver holder writes the resolver file, the
 	// uplink holder's rendering of it is not composed, so it is not a second owner (novox/hq ADR 0247).
 	modules = steppedBack(modules)
-	var problems []string
+	// And only a claimant of a seat naming a path declares it — the controller's generated resources
+	// included, which are judged here at composition (novox/hq ADR 0287).
+	problems := seatPathsOnMachine(modules)
 	owner := map[string]string{}
 	ownedPath := map[string]string{} // path → owning module, for the access check below
 	packagePresent, packageAbsent := map[string][]string{}, map[string][]string{}

internal/catalogue/runtime.go

@@ -303,6 +303,10 @@ func (r Resolution) ownRuntimes(with Rendering) ([]map[string]any, error) {
 		if err != nil {
 			return nil, err
 		}
+		// The holder of node-reads is told where this node keeps its secrets (novox/hq ADR 0310 §5).
+		if words, err = r.readsWords(m, words, with); err != nil {
+			return nil, err
+		}
 		if len(words) > 0 {
 			body, err := json.Marshal(map[string]map[string]string{m.Module: words})
 			if err != nil {