Merge main into feat/1696-declaration-files, keeping mesh-sdk at 86f9a1a5, which holds main's pin 85b5a268

A literal * in a published subject matches the grant's *, so in one shared bucket a node could read every node's files. Each node now
has declaration-files-<node>, which its account reads by name and the controller writes; the sweep judges each bucket against that
node's latest declaration, under the node's lock with the send, and an object the sweep marked is put again by the next send. Putting
that fails send after send raises a condition.

cmd/mesh-controller/busobjects.go

@@ -32,6 +32,13 @@ func assertBusObjects(ctx context.Context, inv *inventory.Inventory, r broker.Ra
 	if err := broker.Raise(r, names); err != nil {
 		return nil, err
 	}
+	// And each node's bucket for the files of its declaration that travel by digest (novox/hq ADR 0486 §4), so a node finds its own
+	// whenever the bus is up.
+	if files, ok := r.(interface{ EnsureDeclarationFiles(nodes []string) error }); ok {
+		if err := files.EnsureDeclarationFiles(names); err != nil {
+			return nil, err
+		}
+	}
 	// The work queues of the mesh's own roles (novox/hq ADR 0121). The queue before the holder,
 	// deliberately: work queues until somebody arrives to do it, so assigning a build machine a week
 	// after something started asking for builds flushes the backlog instead of having lost it.

cmd/mesh-controller/compose_sdk.go

@@ -200,6 +200,7 @@ func composeQuestion(ctx context.Context, open *stores, node string, mode compos
 	}
 	sayFound(ctx, d)
 	out := sendableOf(d)
+	out.fileReferences = readsFileReferences(in.Input, node)
 	if !withOrder {
 		out.Sequence, out.Epoch, out.Generation = 0, 0, 0
 	}
@@ -281,6 +282,7 @@ func composeSendValidated(ctx context.Context, open *stores, node string) (senda
 		if len(left) == 0 && len(in.wouldMake) == 0 {
 			sayFound(ctx, d)
 			out := sendableOf(d)
+			out.fileReferences = readsFileReferences(in.Input, node)
 			// The sender stamps the order it allots (order.stamp); a composition for a send carries none of its own.
 			out.Sequence, out.Epoch, out.Generation = 0, 0, 0
 			here, _ := nodeOf(in.Input, node)

cmd/mesh-controller/container_groups_test.go

@@ -0,0 +1,65 @@
+package main
+
+import (
+	"io"
+	"os"
+	"strings"
+	"testing"
+
+	"git.novox.be/novox/mesh-sdk/go/catalogue"
+)
+
+// Issue 1638 (novox/hq ADR 0480 clause 7), taken in with mesh-sdk's container `groups`: the controller sends a container's
+// groups only to a node-engine that reports the capability container-groups, and holds the module on any other, naming it.
+
+const n8nWithAGroup = `{"module":"n8n","version":"1",
+  "config":{"media-gid":{"type":"number","minimum":1,"required":true,"description":"the group that owns the media library"}},
+  "resources":[{"id":"server","type":"container","name":"n8n",
+    "image":"n8nio/n8n@sha256:4846eb2f4b874ab04cde7fc1e249d2ddaec66e9aea64439beb2972cfea88e3c0",
+    "groups":["${config:media-gid}"]}]}`
+
+// printedBy runs reportUnhostable and returns what it printed.
+func printedBy(t *testing.T, node string, plan catalogue.Resolution) string {
+	t.Helper()
+	stdout := os.Stdout
+	r, w, err := os.Pipe()
+	if err != nil {
+		t.Fatal(err)
+	}
+	os.Stdout = w
+	reportUnhostable(node, plan)
+	w.Close()
+	os.Stdout = stdout
+	out, _ := io.ReadAll(r)
+	return string(out)
+}
+
+// 1638/AC1: a node that reports the capability gets the module; one that does not has it held, the capability named.
+func TestAModuleWithGroupsIsHeldOnANodeThatDoesNotReportTheCapability(t *testing.T) {
+	m, err := catalogue.ParseManifest([]byte(n8nWithAGroup))
+	if err != nil {
+		t.Fatal(err)
+	}
+	shelf := catalogue.Shelf{"n8n": m}
+	reads := catalogue.Node{Name: "ace", Capabilities: map[string]bool{"container-runtime": true, "container-groups": true}}
+	old := catalogue.Node{Name: "g14", Capabilities: map[string]bool{"container-runtime": true}}
+
+	got, err := catalogue.Resolve(shelf, []string{"n8n"}, reads, catalogue.World{})
+	if err != nil || len(got.Unhostable) != 0 || len(got.Modules) != 1 {
+		t.Fatalf("a node that reads groups: %v, held %+v", err, got.Unhostable)
+	}
+	if out := printedBy(t, "ace", got); out != "" {
+		t.Errorf("a node that reads groups was told: %q", out)
+	}
+
+	got, err = catalogue.Resolve(shelf, []string{"n8n"}, old, catalogue.World{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(got.Modules) != 0 || len(got.Unhostable) != 1 {
+		t.Fatalf("n8n was sent to a node that does not report container-groups: hosted %d, held %+v", len(got.Modules), got.Unhostable)
+	}
+	if out := printedBy(t, "g14", got); !strings.Contains(out, "n8n") || !strings.Contains(out, "container-groups") {
+		t.Errorf("the hold does not name the module and the capability: %q", out)
+	}
+}

cmd/mesh-controller/declaration_capability_integration_test.go

@@ -0,0 +1,110 @@
+//go:build integration
+
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+	"testing"
+
+	"git.novox.be/novox/mesh-sdk/go/catalogue"
+	sdkdecl "git.novox.be/novox/mesh-sdk/go/declaration"
+	"git.novox.be/novox/mesh-sdk/go/overlay"
+
+	"git.novox.be/novox/mesh-sdk/go/compose"
+)
+
+// 1696/AC2, ADR 0486 §5: a node is sent a file by digest only when its profile reports the capability. A node whose profile lacks
+// it, and a node the mesh has no profile of, are sent every content inline; a node that reports it is sent the reference. The test
+// goes through composeQuestion and composeSend, the two places readsFileReferences is read (compose_sdk.go).
+func TestAFileTravelsByDigestOnlyToANodeThatReportsTheCapability(t *testing.T) {
+	open := aMesh(t) // anchor and laptop report no file-references
+	ctx := t.Context()
+	big := strings.Repeat("0123456789abcdef", 8<<10) // 128 KiB
+	register(t, open, catalogue.Manifest{Module: "bigfile", Version: "1",
+		Resources: []map[string]any{{"id": "blob", "type": "file", "path": "/etc/bigfile/blob", "mode": "0644", "content": big}}})
+
+	// reader reports the capability; bare has never reported a profile at all.
+	for i, n := range []struct {
+		name    string
+		profile map[string]any
+	}{
+		{"reader", map[string]any{"capabilities": []any{
+			map[string]any{"name": "container-runtime", "present": true},
+			map[string]any{"name": "systemd", "present": true},
+			map[string]any{"name": sdkdecl.FileReferencesCapability, "present": true}}}},
+		{"bare", nil},
+	} {
+		record, err := open.inventory.AddNode(ctx, n.name)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if err := open.inventory.SetPlace(ctx, n.name, n.name+".example:51820", "here", false, fmt.Sprintf("10.77.0.%d", i+10)); err != nil {
+			t.Fatal(err)
+		}
+		if n.profile != nil {
+			if err := open.inventory.RecordProfile(ctx, record.ID, n.profile); err != nil {
+				t.Fatal(err)
+			}
+		}
+		if err := open.inventory.RecordSealingKey(ctx, record.ID, aPublicKey(t)); err != nil {
+			t.Fatal(err)
+		}
+		if err := open.inventory.RecordOverlayKey(ctx, record.ID, aPublicKey(t)); err != nil {
+			t.Fatal(err)
+		}
+		if _, err := open.inventory.Assign(ctx, n.name, overlay.Name); err != nil {
+			t.Fatal(err)
+		}
+	}
+	for _, node := range []string{"laptop", "reader", "bare"} {
+		if _, err := assign(ctx, open, node, "bigfile"); err != nil {
+			t.Fatalf("assign %s: %v", node, err)
+		}
+	}
+
+	byDigest := map[string]bool{"laptop": false, "bare": false, "reader": true}
+	for node, want := range byDigest {
+		asked, _, err := composeQuestion(ctx, open, node, compose.Reading, false)
+		if err != nil {
+			t.Fatalf("%s: %v", node, err)
+		}
+		sent, err := composeSend(ctx, open, node)
+		if err != nil {
+			t.Fatalf("%s: %v", node, err)
+		}
+		for what, s := range map[string]sendable{"question": asked, "send": sent} {
+			if s.fileReferences != want {
+				t.Fatalf("%s, %s: fileReferences %v, want %v", node, what, s.fileReferences, want)
+			}
+			body, err := s.Body()
+			if err != nil {
+				t.Fatal(err)
+			}
+			var got struct {
+				Resources []map[string]any `json:"resources"`
+			}
+			if err := json.Unmarshal(body, &got); err != nil {
+				t.Fatal(err)
+			}
+			var found bool
+			for _, r := range got.Resources {
+				if r["path"] != "/etc/bigfile/blob" {
+					continue
+				}
+				found = true
+				inline := r["content"] == big
+				if want && (inline || r["digest"] == nil || r["size"] == nil) {
+					t.Fatalf("%s, %s: a node that reads references is sent the content inline", node, what)
+				}
+				if !want && (!inline || r["digest"] != nil) {
+					t.Fatalf("%s, %s: a node that does not report the capability is sent a reference", node, what)
+				}
+			}
+			if !found {
+				t.Fatalf("%s, %s: the file is not in the declaration", node, what)
+			}
+		}
+	}
+}

cmd/mesh-controller/declaration_files.go

@@ -0,0 +1,253 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"sort"
+	"sync"
+
+	"git.novox.be/novox/mesh-sdk/go/compose"
+	sdkdecl "git.novox.be/novox/mesh-sdk/go/declaration"
+	"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/conditions"
+)
+
+// **A declaration's large files travel by their digest to a node that can read one** (novox/hq ADR 0486 §1, §5, issue 1696).
+//
+// The declaration to a node that reports sdkdecl.FileReferencesCapability carries, in place of the content of every
+// file resource of more than sdkdecl.FileReferenceThreshold bytes that may travel so (File.TravelsByDigest: plain content or
+// bytes, not sealed, not filled with secrets, not written into another file), its sha256 digest and size. The content is put
+// into the bucket of the bus under the hex of the digest before the declaration is sent. A node that does not report the
+// capability is sent every content inline, as before: an older node-engine refuses a field it does not know, whole.
+
+// readsFileReferences says the node reports the capability of reading a file given by digest (ADR 0486 §5). A node the mesh has
+// no profile of reads none.
+func readsFileReferences(in compose.Input, node string) bool {
+	n, ok := nodeOf(in, node)
+	return ok && n.Capabilities[sdkdecl.FileReferencesCapability]
+}
+
+// referencing is the resources as a node that reads references is sent them, and the content of each file that went by
+// digest, by the name of its object (the hex of its digest). The resources it is given are not changed. A file that does not
+// travel by digest is passed as it is.
+func referencing(resources []map[string]any) ([]map[string]any, map[string][]byte, error) {
+	out := make([]map[string]any, len(resources))
+	var objects map[string][]byte
+	for i, r := range resources {
+		out[i] = r
+		if kind, _ := r["type"].(string); kind != string(sdkdecl.TypeFile) {
+			continue
+		}
+		// Cheap first: only a file with a content or bytes of the size is worth reading whole.
+		content, _ := r["content"].(string)
+		bytesField, _ := r["bytes"].(string)
+		if len(content) <= sdkdecl.FileReferenceThreshold && len(bytesField) <= sdkdecl.FileReferenceThreshold {
+			continue
+		}
+		raw, err := json.Marshal(r)
+		if err != nil {
+			return nil, nil, fmt.Errorf("resource %v: %w", r["id"], err)
+		}
+		var f sdkdecl.File
+		if err := json.Unmarshal(raw, &f); err != nil {
+			return nil, nil, fmt.Errorf("resource %v is not a file the controller can read: %w", r["id"], err)
+		}
+		if !f.TravelsByDigest() {
+			continue
+		}
+		ref, body, err := f.AsReference()
+		if err != nil {
+			return nil, nil, err
+		}
+		name, err := sdkdecl.ObjectName(ref.Digest)
+		if err != nil {
+			return nil, nil, err
+		}
+		with := make(map[string]any, len(r)+2)
+		for k, v := range r {
+			with[k] = v
+		}
+		delete(with, "content")
+		delete(with, "bytes")
+		with["digest"], with["size"] = ref.Digest, ref.Size
+		out[i] = with
+		if objects == nil {
+			objects = map[string][]byte{}
+		}
+		objects[name] = body
+	}
+	return out, objects, nil
+}
+
+// namedObjects are the objects of the bucket a body names: the object name of every file resource given by reference,
+// with its size. It reads a declaration as the node does, so it also reads the latest one the bus holds.
+func namedObjects(body []byte) (map[string]int64, error) {
+	var envelope struct {
+		Resources []struct {
+			Type   string `json:"type"`
+			Digest string `json:"digest"`
+			Size   int64  `json:"size"`
+		} `json:"resources"`
+	}
+	if err := json.Unmarshal(body, &envelope); err != nil {
+		return nil, err
+	}
+	var out map[string]int64
+	for _, r := range envelope.Resources {
+		if r.Type != string(sdkdecl.TypeFile) || r.Digest == "" {
+			continue
+		}
+		name, err := sdkdecl.ObjectName(r.Digest)
+		if err != nil {
+			return nil, err
+		}
+		if out == nil {
+			out = map[string]int64{}
+		}
+		out[name] = r.Size
+	}
+	return out, nil
+}
+
+// objectStore is what putting the objects needs of a node's bucket.
+type objectStore interface {
+	// Has says whether an object of that name is there, complete, and whether it carries the sweep's mark of being named by no
+	// node's latest declaration.
+	Has(ctx context.Context, name string) (have, marked bool, err error)
+	// Put writes the object under that name, replacing one of the same name (and so erasing its mark).
+	Put(ctx context.Context, name string, content []byte) error
+}
+
+// putObjects makes sure every object of the declaration is in the bucket before the declaration that names it is sent: a node
+// that reads the declaration finds each object. An object already there (the same content, the same name) is not written again,
+// **unless the sweep marked it unnamed**: then it is written again, so the mark that would have it removed is gone with the
+// old object (issue 1696, review: a mark read just before a send must not take an object the send relies on). Refuses on the
+// first it cannot put, naming it, so the declaration is not sent.
+func putObjects(ctx context.Context, store objectStore, objects map[string][]byte) error {
+	names := make([]string, 0, len(objects))
+	for name := range objects {
+		names = append(names, name)
+	}
+	sort.Strings(names)
+	for _, name := range names {
+		have, marked, err := store.Has(ctx, name)
+		if err != nil {
+			return fmt.Errorf("whether the object %s is in the bucket: %w", name[:12], err)
+		}
+		if have && !marked {
+			continue
+		}
+		if err := store.Put(ctx, name, objects[name]); err != nil {
+			return fmt.Errorf("putting the object %s (%d bytes) in the bucket: %w", name[:12], len(objects[name]), err)
+		}
+	}
+	return nil
+}
+
+// busObjects is a node's bucket on the controller's own connection.
+type busObjects struct{ store jetstream.ObjectStore }
+
+// openBucket opens the bucket of a node's files, making it first if it is not there (it is asserted for every node at the
+// controller's start; a node adopted since is covered here).
+func openBucket(ctx context.Context, conn *nats.Conn, node string) (busObjects, error) {
+	js, err := jetstream.New(conn)
+	if err != nil {
+		return busObjects{}, err
+	}
+	bucket, err := broker.DeclarationFilesBucketOf(node)
+	if err != nil {
+		return busObjects{}, fmt.Errorf("the object bucket of node %q: %w", node, err)
+	}
+	store, err := js.ObjectStore(ctx, bucket)
+	if errors.Is(err, jetstream.ErrBucketNotFound) {
+		if err = broker.EnsureDeclarationFiles(ctx, js, node); err == nil {
+			store, err = js.ObjectStore(ctx, bucket)
+		}
+	}
+	if err != nil {
+		return busObjects{}, fmt.Errorf("the object bucket %s: %w", bucket, err)
+	}
+	return busObjects{store}, nil
+}
+
+func (b busObjects) Has(ctx context.Context, name string) (bool, bool, error) {
+	info, err := b.store.GetInfo(ctx, name)
+	switch {
+	case errors.Is(err, jetstream.ErrObjectNotFound):
+		return false, false, nil
+	case err != nil:
+		return false, false, err
+	}
+	_, marked := info.Metadata[declarationUnnamed]
+	return !info.Deleted, marked, nil
+}
+
+func (b busObjects) Put(ctx context.Context, name string, content []byte) error {
+	_, err := b.store.PutBytes(ctx, name, content)
+	return err
+}
+
+// filesLocks hold a node's bucket for one act at a time in this process: a send puts its objects and publishes the declaration that
+// names them under the node's lock, and the sweep judges the node's bucket under the same one, so the sweep never removes an
+// object between a send's put and its declaration. Another process (a person's push) is covered by the put erasing a mark and by
+// the sweep looking at an object again just before it removes it.
+var filesLocks sync.Map
+
+func lockFilesOf(node string) func() {
+	l, _ := filesLocks.LoadOrStore(node, &sync.Mutex{})
+	mu := l.(*sync.Mutex)
+	mu.Lock()
+	return mu.Unlock
+}
+
+// kindFilesNotPut is a node whose files that travel by digest could not be put in its bucket, send after send.
+const kindFilesNotPut = "declaration-files-not-put"
+
+// filesNotPutAfter is how many sends in a row may fail to put before the condition is raised: the first send to the machine holding
+// the bus fails for want of the grant that very send delivers, and says so, and is not yet a fault.
+const filesNotPutAfter = 2
+
+var (
+	filesFailMu sync.Mutex
+	filesFailed = map[string]int{}
+)
+
+func filesNotPutObservation(node, summary string) conditions.Observation {
+	return conditions.Observation{Scope: conditions.ScopeMachine, ID: node, Kind: kindFilesNotPut, Token: kindFilesNotPut,
+		Machine: node, Severity: conditions.Warning, Source: "sends", Summary: summary}
+}
+
+// notePut records how putting a send's objects went: a failure counts, the second in a row raises the condition, a success
+// clears the count and the condition.
+func notePut(ctx context.Context, node string, put error) {
+	filesFailMu.Lock()
+	if put == nil {
+		delete(filesFailed, node)
+	} else {
+		filesFailed[node]++
+	}
+	n := filesFailed[node]
+	filesFailMu.Unlock()
+	keeper := conditionsFrom
+	if keeper == nil {
+		return
+	}
+	key := filesNotPutObservation(node, "").Key()
+	switch {
+	case put == nil:
+		if _, err := keeper.Clear(ctx, key, node+" was sent its files by digest"); err != nil {
+			fmt.Printf("the condition %s could not be cleared: %v\n", key, err)
+		}
+	case n >= filesNotPutAfter:
+		summary := fmt.Sprintf("%s's files that travel by digest could not be put in its bucket %d sends in a row, so it is sent them "+
+			"inline: %v", node, n, put)
+		if _, err := keeper.Observe(ctx, filesNotPutObservation(node, summary)); err != nil {
+			fmt.Printf("the condition %s could not be raised: %v\n", key, err)
+		}
+	}
+}

cmd/mesh-controller/declaration_files_integration_test.go

@@ -0,0 +1,246 @@
+//go:build integration
+
+package main
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"strings"
+	"testing"
+	"time"
+
+	sdkdecl "git.novox.be/novox/mesh-sdk/go/declaration"
+	"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/link"
+	"github.com/novox/mesh-controller/internal/testbus"
+)
+
+type sigOf struct{}
+
+func (sigOf) Sign(context.Context, []byte) ([]byte, error) { return make([]byte, 64), nil }
+
+// 1696/AC7 (ADR 0486 §1): on a real bus with its default largest message of 1 MiB, a declaration whose files add up to more than
+// 3 MiB is sent as references, its objects are in the bucket, each fetched back whole and verified against the digest and size the
+// declaration names; the same declaration inline is refused by the controller, naming size and limit. A changed byte in an object
+// fails the verification.
+func TestADeclarationOfMoreThanThreeMiBIsSentByReferenceOnARealBus(t *testing.T) { // 1696/AC7
+	s := testbus.Start(t)
+	conn, err := nats.Connect(s.ClientURL())
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer conn.Close()
+	nc, err := conn.JetStream()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err := nc.AddStream(&nats.StreamConfig{Name: "NODES", Subjects: []string{"mesh.node.*.declare"},
+		MaxMsgsPerSubject: 1}); err != nil {
+		t.Fatal(err)
+	}
+	ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second)
+	defer cancel()
+	api, err := jetstream.New(conn)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := broker.EnsureDeclarationFiles(ctx, api, "novox"); err != nil {
+		t.Fatal(err)
+	}
+	// Run twice: an assertion of an existing bucket is no error and no change.
+	if err := broker.EnsureDeclarationFiles(ctx, api, "novox"); err != nil {
+		t.Fatalf("asserting the bucket again: %v", err)
+	}
+
+	var resources []map[string]any
+	for i := 0; i < 3; i++ {
+		resources = append(resources, aFileResource("big-"+string(rune('a'+i)), contentOf("big"+string(rune('a'+i)), 1200<<10)))
+	}
+	resources = append(resources, aFileResource("small", "tiny\n"))
+	inline := sendable{Resources: resources}
+	byDigest := sendable{fileReferences: true, Resources: resources}
+
+	bus := link.OverNATS{Conn: conn, JS: nc}
+	body, err := inline.Body()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := link.Declare(ctx, bus, sigOf{}, "novox", body, 5*time.Second); err == nil ||
+		!strings.Contains(err.Error(), "1048576") || strings.Contains(err.Error(), "maximum payload exceeded") {
+		t.Fatalf("the inline declaration of more than 3 MiB: %v", err)
+	}
+
+	bucket, err := openBucket(ctx, conn, "novox")
+	if err != nil {
+		t.Fatal(err)
+	}
+	objects, err := byDigest.objects()
+	if err != nil || len(objects) != 3 {
+		t.Fatalf("objects: %d %v", len(objects), err)
+	}
+	if err := putObjects(ctx, bucket, objects); err != nil {
+		t.Fatal(err)
+	}
+	if err := putObjects(ctx, bucket, objects); err != nil {
+		t.Fatalf("putting them again: %v", err)
+	}
+	refBody, err := byDigest.Body()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := link.Declare(ctx, bus, sigOf{}, "novox", refBody, 5*time.Second); err != nil {
+		t.Fatalf("the declaration by reference: %v", err)
+	}
+
+	// What the stream holds for the node is the reference form, and it names exactly the three objects.
+	latest, err := latestDeclarations(ctx, conn, []string{"novox", "ace"})
+	if err != nil || len(latest) != 1 {
+		t.Fatalf("the latest declarations: %v %v", len(latest), err)
+	}
+	named, err := namedByLatest("novox", latest["novox"])
+	if err != nil || len(named) != 3 {
+		t.Fatalf("what the latest declaration names: %v %v", named, err)
+	}
+	novoxBucket, err := broker.DeclarationFilesBucketOf("novox")
+	if err != nil {
+		t.Fatal(err)
+	}
+	store, err := api.ObjectStore(ctx, novoxBucket)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var envelope struct {
+		Resources []sdkdecl.File `json:"resources"`
+	}
+	if err := json.Unmarshal(refBody, &envelope); err != nil {
+		t.Fatal(err)
+	}
+	for _, f := range envelope.Resources {
+		if !f.IsReference() {
+			continue
+		}
+		name, _ := sdkdecl.ObjectName(f.Digest)
+		got, err := store.GetBytes(ctx, name)
+		if err != nil {
+			t.Fatalf("the object of %s: %v", f.ID, err)
+		}
+		if err := f.Verify(got); err != nil {
+			t.Errorf("the object does not verify: %v", err)
+		}
+		got[len(got)/2] ^= 1
+		if err := f.Verify(got); err == nil {
+			t.Errorf("a changed byte in the object of %s passed the verification", f.ID)
+		}
+	}
+
+	// The sweep against the real bucket: all named, nothing marked; a fourth object named by none is marked, kept a day less a
+	// minute, and removed at the day.
+	extra := bytes.Repeat([]byte("x"), 100)
+	extraName := strings.Repeat("e", 64)
+	if err := putObjects(ctx, bucket, map[string][]byte{extraName: extra}); err != nil {
+		t.Fatal(err)
+	}
+	b := busSweptBucket{store}
+	t0 := time.Now()
+	if r, err := sweepDeclarationFiles(ctx, b, named, t0); err != nil || r.Marked != 1 || r.Removed != 0 || r.Kept != 3 {
+		t.Fatalf("first sweep: %+v %v", r, err)
+	}
+	if r, err := sweepDeclarationFiles(ctx, b, named, t0.Add(24*time.Hour-time.Minute)); err != nil || r.Removed != 0 {
+		t.Fatalf("a minute short of a day: %+v %v", r, err)
+	}
+	if r, err := sweepDeclarationFiles(ctx, b, named, t0.Add(24*time.Hour+time.Second)); err != nil || r.Removed != 1 {
+		t.Fatalf("a day after: %+v %v", r, err)
+	}
+	if infos, err := store.List(ctx); err != nil || len(infos) != 3 {
+		t.Fatalf("the bucket holds %d objects (%v), want the 3 the declaration names", len(infos), err)
+	}
+}
+
+// 1696/AC8 on a real bucket: the sweep removes an object only if it still carries the mark it judged it by. An object marked
+// unnamed, then put again by a send (which erases the mark), is kept when the sweep deletes it by the old mark.
+func TestTheSweepsDeleteLeavesAnObjectASendPutAgainAfterItWasMarked(t *testing.T) { // 1696/AC8
+	s := testbus.Start(t)
+	conn, err := nats.Connect(s.ClientURL())
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer conn.Close()
+	ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second)
+	defer cancel()
+	bucket, err := openBucket(ctx, conn, "novox")
+	if err != nil {
+		t.Fatal(err)
+	}
+	name := strings.Repeat("a", 64)
+	content := map[string][]byte{name: bytes.Repeat([]byte("y"), 100)}
+	if err := putObjects(ctx, bucket, content); err != nil {
+		t.Fatal(err)
+	}
+	b := busSweptBucket{bucket.store}
+	judged := time.Now().Add(-25 * time.Hour).Truncate(time.Second)
+	if err := b.MarkUnnamed(ctx, name, judged); err != nil {
+		t.Fatal(err)
+	}
+	if _, marked, err := bucket.Has(ctx, name); err != nil || !marked {
+		t.Fatalf("the object was not marked: %v %v", marked, err)
+	}
+	// The sweep has read the mark; a send now puts the object again, which erases it.
+	if err := putObjects(ctx, bucket, content); err != nil {
+		t.Fatal(err)
+	}
+	if have, marked, err := bucket.Has(ctx, name); err != nil || !have || marked {
+		t.Fatalf("a send did not put the marked object again: have %v marked %v %v", have, marked, err)
+	}
+	gone, err := b.Delete(ctx, name, judged)
+	if err != nil || gone {
+		t.Fatalf("the sweep deleted by an old mark: gone %v, %v", gone, err)
+	}
+	if have, _, err := bucket.Has(ctx, name); err != nil || !have {
+		t.Fatalf("the object a send relies on is gone: %v %v", have, err)
+	}
+	// And the mark still on it is honoured: marked again and deleted by that mark, it goes.
+	if err := b.MarkUnnamed(ctx, name, judged); err != nil {
+		t.Fatal(err)
+	}
+	if gone, err := b.Delete(ctx, name, judged); err != nil || !gone {
+		t.Fatalf("an object still carrying the mark it was judged by is kept: gone %v, %v", gone, err)
+	}
+}
+
+// 1696/AC9 on a real bus: the sweep of a node's bucket takes the node's lock first, so it waits for a send that has put its objects
+// and not yet published the declaration that names them.
+func TestTheSweepOfANodesBucketHoldsTheNodesLock(t *testing.T) { // 1696/AC9
+	s := testbus.Start(t)
+	conn, err := nats.Connect(s.ClientURL())
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer conn.Close()
+	ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second)
+	defer cancel()
+	const node = "sweep-lock-node"
+	if _, err := openBucket(ctx, conn, node); err != nil { // the bucket exists, or the sweep would return before the lock
+		t.Fatal(err)
+	}
+	release := lockFilesOf(node) // a send is between its put and its publication
+	done := make(chan struct{})
+	go func() {
+		_, _ = sweepNode(ctx, conn, node)
+		close(done)
+	}()
+	select {
+	case <-done:
+		t.Fatal("the sweep judged the node's bucket while a send held it")
+	case <-time.After(300 * time.Millisecond):
+	}
+	release()
+	select {
+	case <-done:
+	case <-time.After(20 * time.Second):
+		t.Fatal("the sweep did not go on once the send let go")
+	}
+}

cmd/mesh-controller/declaration_files_test.go

@@ -0,0 +1,534 @@
+package main
+
+import (
+	"context"
+	"encoding/base64"
+	"encoding/hex"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"strings"
+	"testing"
+	"time"
+
+	sdkdecl "git.novox.be/novox/mesh-sdk/go/declaration"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// contentOf is a deterministic content of n bytes that does not compress to nothing and holds no character JSON escapes.
+func contentOf(seed string, n int) string {
+	var b strings.Builder
+	for i := 0; b.Len() < n; i++ {
+		fmt.Fprintf(&b, "%s-%07d-%x;", seed, i, i*2654435761%1000003)
+	}
+	return b.String()[:n]
+}
+
+func aFileResource(id, content string) map[string]any {
+	return map[string]any{"id": id, "type": "file", "path": "/etc/" + id, "mode": "0644", "content": content}
+}
+
+// controlNodeShape is a declaration shaped like the control node's on 2026-10-21 (issue 1689), the sizes measured then: a bus users
+// file of 252,678 bytes, the vault's export of 138,475 bytes (compact), the tool runtime 21 KB, the packet filter 19 KB, the launcher
+// 14 KB, and about 600 small resources for the rest (about 286 KB). `more` scales the count of small ones: 1 is the shape, 1.4 forty
+// percent more of them.
+func controlNodeShape(more float64) []map[string]any {
+	res := []map[string]any{
+		aFileResource("nats.bus-users", contentOf("users", 252678)),
+		aFileResource("mesh-vault.kept", contentOf("kept", 138475)),
+		aFileResource("node-tools.runtime", contentOf("runtime", 21<<10)),
+		aFileResource("nftables.filtering", contentOf("filter", 19<<10)),
+		aFileResource("mesh-host.launcher", contentOf("launcher", 14<<10)),
+	}
+	for i := 0; i < int(600*more); i++ {
+		res = append(res, aFileResource(fmt.Sprintf("module-%03d.config", i), contentOf(fmt.Sprintf("small%d", i), 380)))
+	}
+	return res
+}
+
+func wireSizeOf(t *testing.T, s sendable) int {
+	t.Helper()
+	body, err := s.Body()
+	if err != nil {
+		t.Fatal(err)
+	}
+	// The signature the controller's key makes is 64 bytes.
+	msg, err := link.Envelope(body, make([]byte, 64))
+	if err != nil {
+		t.Fatal(err)
+	}
+	return len(msg)
+}
+
+// 1696/AC1: for a node that reports the capability, the two big files of a control-node-shaped declaration carry their digest and size
+// and no content, and the declaration is far under the bus's 1 MiB.
+func TestAFileOver64KiBTravelsByDigestToANodeThatReadsOne(t *testing.T) { // 1696/AC1
+	users, kept := contentOf("users", 252678), contentOf("kept", 138475)
+	s := sendable{fileReferences: true, Resources: []map[string]any{
+		aFileResource("nats.bus-users", users), aFileResource("mesh-vault.kept", kept),
+		aFileResource("small", "tiny\n"),
+	}}
+	body, err := s.Body()
+	if err != nil {
+		t.Fatal(err)
+	}
+	var got struct {
+		Resources []map[string]any `json:"resources"`
+	}
+	if err := json.Unmarshal(body, &got); err != nil {
+		t.Fatal(err)
+	}
+	for i, want := range []string{users, kept} {
+		r := got.Resources[i]
+		digest := sdkdecl.DigestOf([]byte(want))
+		if _, has := r["content"]; has || r["digest"] != digest || r["size"] != float64(len(want)) {
+			t.Errorf("%v goes with content %v, digest %v, size %v; want no content, %s and %d", r["id"], r["content"] != nil,
+				r["digest"], r["size"], digest, len(want))
+		}
+		if r["path"] == nil || r["mode"] != "0644" {
+			t.Errorf("%v lost its path or mode: %v", r["id"], r)
+		}
+	}
+	if got.Resources[2]["content"] != "tiny\n" || got.Resources[2]["digest"] != nil {
+		t.Errorf("a small file is not inline: %v", got.Resources[2])
+	}
+	if strings.Contains(string(body), users[:200]) || strings.Contains(string(body), kept[:200]) {
+		t.Error("the content of a file that went by digest is in the body")
+	}
+	if n := wireSizeOf(t, s); n > 100<<10 {
+		t.Errorf("the declaration is %d bytes on the wire, want under 100 KB", n)
+	}
+	// The objects to put are the contents, each under the hex of its digest, and a reference verifies against its object.
+	objects, err := s.objects()
+	if err != nil || len(objects) != 2 {
+		t.Fatalf("objects: %v %v", objects, err)
+	}
+	for _, want := range []string{users, kept} {
+		name, _ := sdkdecl.ObjectName(sdkdecl.DigestOf([]byte(want)))
+		if string(objects[name]) != want {
+			t.Errorf("the object %s does not hold the content", name[:12])
+		}
+	}
+	named, err := namedObjects(body)
+	if err != nil || len(named) != 2 {
+		t.Fatalf("the objects the body names: %v %v", named, err)
+	}
+	for name := range objects {
+		if _, ok := named[name]; !ok {
+			t.Errorf("the body does not name the object %s it was sent with", name[:12])
+		}
+		if _, err := hex.DecodeString(name); err != nil || len(name) != 64 {
+			t.Errorf("the object name %q is not 64 hex characters", name)
+		}
+	}
+}
+
+// 1696/AC2: a node that does not report the capability is sent every content inline, as before, and has no object put.
+func TestANodeWithoutTheCapabilityIsSentEveryContentInline(t *testing.T) { // 1696/AC2
+	users := contentOf("users", 252678)
+	s := sendable{Resources: []map[string]any{aFileResource("nats.bus-users", users)}}
+	body, err := s.Body()
+	if err != nil {
+		t.Fatal(err)
+	}
+	var got struct {
+		Resources []map[string]any `json:"resources"`
+	}
+	if err := json.Unmarshal(body, &got); err != nil {
+		t.Fatal(err)
+	}
+	if got.Resources[0]["content"] != users || got.Resources[0]["digest"] != nil || got.Resources[0]["size"] != nil {
+		t.Fatalf("a node that reads no references is not sent the content inline: %v", got.Resources[0]["digest"])
+	}
+	if objects, err := s.objects(); err != nil || len(objects) != 0 {
+		t.Fatalf("objects for a node that reads none: %v %v", len(objects), err)
+	}
+}
+
+// 1696/AC3: only a file that may travel by digest does: one of exactly 64 KiB, a sealed one, one filled with secrets, one written
+// into another file, and a directory stay inline, whatever the node reads.
+func TestOnlyAFileThatMayTravelByDigestDoes(t *testing.T) { // 1696/AC3
+	exact := contentOf("exact", 64<<10)
+	big := contentOf("big", 64<<10+1)
+	sealed := aFileResource("sealed", big)
+	sealed["sealed"], sealed["content"] = "box", ""
+	sealed["content"] = big // a sealed file's content is none; the body must pass it as it is, whatever it holds
+	secret := aFileResource("secret", big)
+	secret["secrets"] = map[string]any{"token": "x"}
+	into := aFileResource("into", big)
+	into["into"] = "/etc/other"
+	s := sendable{fileReferences: true, Resources: []map[string]any{
+		aFileResource("exact", exact), sealed, secret, into,
+		{"id": "dir", "type": "directory", "path": "/etc/d", "content": big},
+		aFileResource("big", big),
+	}}
+	body, err := s.Body()
+	if err != nil {
+		t.Fatal(err)
+	}
+	var got struct {
+		Resources []map[string]any `json:"resources"`
+	}
+	if err := json.Unmarshal(body, &got); err != nil {
+		t.Fatal(err)
+	}
+	for i, id := range []string{"exact", "sealed", "secret", "into", "dir"} {
+		if got.Resources[i]["id"] != id || got.Resources[i]["digest"] != nil || got.Resources[i]["content"] == nil {
+			t.Errorf("%s went by digest or lost its content: %v", id, got.Resources[i]["digest"])
+		}
+	}
+	if big := got.Resources[5]; big["id"] != "big" || big["digest"] == nil || big["content"] != nil {
+		t.Errorf("a plain file of 64 KiB and a byte did not go by digest: %v", big["digest"])
+	}
+}
+
+// A file given as bytes goes by digest on its decoded length, with the decoded bytes in the object.
+func TestAFileOfBytesTravelsByDigestOnItsDecodedLength(t *testing.T) {
+	raw := []byte(contentOf("png", 70<<10))
+	r := map[string]any{"id": "icon", "type": "file", "path": "/usr/share/icon.png", "bytes": stdBase64(raw)}
+	s := sendable{fileReferences: true, Resources: []map[string]any{r}}
+	objects, err := s.objects()
+	if err != nil || len(objects) != 1 {
+		t.Fatalf("%v %v", len(objects), err)
+	}
+	name, _ := sdkdecl.ObjectName(sdkdecl.DigestOf(raw))
+	if string(objects[name]) != string(raw) {
+		t.Fatal("the object is not the decoded bytes")
+	}
+	if r["bytes"] == nil {
+		t.Fatal("the composed resource was changed in place")
+	}
+}
+
+type memObjects struct {
+	have   map[string][]byte
+	marked map[string]bool
+	puts   []string
+	fail   map[string]error
+}
+
+func (m *memObjects) Has(_ context.Context, name string) (bool, bool, error) {
+	_, ok := m.have[name]
+	return ok, m.marked[name], nil
+}
+func (m *memObjects) Put(_ context.Context, name string, c []byte) error {
+	if err := m.fail[name]; err != nil {
+		return err
+	}
+	m.puts = append(m.puts, name)
+	m.have[name] = c
+	delete(m.marked, name)
+	return nil
+}
+
+// 1696/AC4: an object already in the bucket is not put again, one absent is, and a put that fails stops the send, naming the object.
+func TestObjectsAreInTheBucketBeforeTheDeclarationIsSent(t *testing.T) { // 1696/AC4
+	objects := map[string][]byte{strings.Repeat("a", 64): []byte("one"), strings.Repeat("b", 64): []byte("two")}
+	b := &memObjects{have: map[string][]byte{strings.Repeat("a", 64): []byte("one")}}
+	if err := putObjects(t.Context(), b, objects); err != nil || len(b.puts) != 1 || b.puts[0] != strings.Repeat("b", 64) {
+		t.Fatalf("put %v (%v), want the one absent", b.puts, err)
+	}
+	// An object the sweep marked unnamed is put again, which erases the mark: a send relies on it.
+	b = &memObjects{have: map[string][]byte{strings.Repeat("a", 64): []byte("one"), strings.Repeat("b", 64): []byte("two")},
+		marked: map[string]bool{strings.Repeat("a", 64): true}}
+	if err := putObjects(t.Context(), b, objects); err != nil || len(b.puts) != 1 || b.puts[0] != strings.Repeat("a", 64) || b.marked[strings.Repeat("a", 64)] {
+		t.Fatalf("a marked object: put %v (%v) marked %v, want it put again and the mark gone", b.puts, err, b.marked)
+	}
+	b = &memObjects{have: map[string][]byte{}, fail: map[string]error{strings.Repeat("a", 64): errors.New("permissions violation")}}
+	err := putObjects(t.Context(), b, objects)
+	if err == nil || !strings.Contains(err.Error(), "aaaaaaaaaaaa") || !strings.Contains(err.Error(), "permissions violation") {
+		t.Fatalf("a failed put: %v", err)
+	}
+}
+
+// fallbackDelivery refuses the first declaration it is sent with the bucket's failure, as a bus that has not yet been given the
+// controller's grant does, and takes the second.
+type fallbackDelivery struct {
+	bodies [][]byte
+	first  error
+}
+
+func (f *fallbackDelivery) grant(context.Context, []readyNode) error { return nil }
+func (f *fallbackDelivery) declare(_ context.Context, _ readyNode, body []byte) (string, error) {
+	f.bodies = append(f.bodies, body)
+	if len(f.bodies) == 1 && f.first != nil {
+		return "", fmt.Errorf("x: %w: %w", errFilesNotPut, f.first)
+	}
+	return "digest", nil
+}
+
+// 1696/AC5: when the bucket cannot be written yet (the grant travels in the declaration of the machine holding the bus), that send goes
+// with every content inline and is made; a send that fails for another reason is not retried inline.
+func TestASendWhoseFilesCannotBePutGoesInlineOnce(t *testing.T) { // 1696/AC5
+	users := contentOf("users", 100<<10)
+	s := readyNode{node: "novox", declared: sendable{fileReferences: true, Resources: []map[string]any{aFileResource("nats.bus-users", users)}}}
+	f := &fallbackDelivery{first: errors.New("timeout")}
+	digests, err := deliver(t.Context(), f, "novox", []readyNode{s})
+	if err != nil || digests["novox"] != "digest" || len(f.bodies) != 2 {
+		t.Fatalf("%v %v %d", digests, err, len(f.bodies))
+	}
+	if strings.Contains(string(f.bodies[0]), users[:100]) || !strings.Contains(string(f.bodies[1]), users[:100]) {
+		t.Error("the first body should name the file by digest and the second carry it inline")
+	}
+	other := &fallbackDelivery{}
+	other.first = nil
+	failing := &failingDelivery{err: errors.New("the bus is down")}
+	if _, err := deliver(t.Context(), failing, "novox", []readyNode{s}); err == nil || failing.calls != 1 {
+		t.Fatalf("a failure of another kind: %v after %d send(s)", err, failing.calls)
+	}
+}
+
+type failingDelivery struct {
+	err   error
+	calls int
+}
+
+func (f *failingDelivery) grant(context.Context, []readyNode) error { return nil }
+func (f *failingDelivery) declare(context.Context, readyNode, []byte) (string, error) {
+	f.calls++
+	return "", f.err
+}
+
+// A bucket for the sweep.
+type sweepBucketFake struct {
+	objects map[string]time.Time // zero: named at the last look
+	deleted []string
+}
+
+func (b *sweepBucketFake) Objects(context.Context) ([]bucketObject, error) {
+	var out []bucketObject
+	for n, at := range b.objects {
+		out = append(out, bucketObject{Name: n, UnnamedSince: at})
+	}
+	return out, nil
+}
+func (b *sweepBucketFake) MarkUnnamed(_ context.Context, n string, at time.Time) error {
+	b.objects[n] = at
+	return nil
+}
+func (b *sweepBucketFake) ClearUnnamed(_ context.Context, n string) error {
+	b.objects[n] = time.Time{}
+	return nil
+}
+func (b *sweepBucketFake) Delete(_ context.Context, n string, markedAt time.Time) (bool, error) {
+	if at, ok := b.objects[n]; !ok || !at.Equal(markedAt) {
+		return false, nil // put again since it was judged: its mark is gone
+	}
+	delete(b.objects, n)
+	b.deleted = append(b.deleted, n)
+	return true, nil
+}
+
+// 1696/AC6: an object a latest declaration still names is not removed, however long; one unnamed is marked at the first look and removed
+// only when the mark is 24 hours old; one named again loses its mark.
+func TestAnObjectIsRemovedADayAfterNoLatestDeclarationNamesIt(t *testing.T) { // 1696/AC6
+	named, unnamed, back := strings.Repeat("1", 64), strings.Repeat("2", 64), strings.Repeat("3", 64)
+	t0 := time.Date(2026, 10, 21, 12, 0, 0, 0, time.UTC)
+	b := &sweepBucketFake{objects: map[string]time.Time{named: t0.Add(-100 * time.Hour), unnamed: {}, back: t0.Add(-5 * time.Hour)}}
+	named3 := map[string]bool{named: true, back: true}
+	r, err := sweepDeclarationFiles(t.Context(), b, named3, t0)
+	if err != nil || r.Marked != 1 || r.Cleared != 2 || r.Removed != 0 || len(b.deleted) != 0 {
+		t.Fatalf("first look: %+v %v %v", r, err, b.deleted)
+	}
+	if !b.objects[named].IsZero() || !b.objects[back].IsZero() || !b.objects[unnamed].Equal(t0) {
+		t.Fatalf("marks after the first look: %v", b.objects)
+	}
+	// Still unnamed 23 hours 59 minutes later: kept. A day after the mark: removed. The named ones stay for ever.
+	if r, err = sweepDeclarationFiles(t.Context(), b, map[string]bool{named: true, back: true}, t0.Add(24*time.Hour-time.Minute)); err != nil ||
+		r.Removed != 0 || len(b.deleted) != 0 {
+		t.Fatalf("a minute short of a day: %+v %v %v", r, err, b.deleted)
+	}
+	if r, err = sweepDeclarationFiles(t.Context(), b, map[string]bool{named: true, back: true}, t0.Add(24*time.Hour)); err != nil ||
+		r.Removed != 1 || len(b.deleted) != 1 || b.deleted[0] != unnamed {
+		t.Fatalf("a day after: %+v %v %v", r, err, b.deleted)
+	}
+	if _, ok := b.objects[named]; !ok {
+		t.Fatal("an object a latest declaration names was removed")
+	}
+	// An object named again before the day is up loses its mark and is not removed.
+	b = &sweepBucketFake{objects: map[string]time.Time{unnamed: t0}}
+	if _, err := sweepDeclarationFiles(t.Context(), b, map[string]bool{unnamed: true}, t0.Add(23*time.Hour)); err != nil || !b.objects[unnamed].IsZero() {
+		t.Fatalf("named again: %v %v", b.objects, err)
+	}
+}
+
+// What a node's latest declaration names is read from the signed envelope as stored on the bus; an unreadable one is an error and
+// never "names none", which would mark an object a node needs.
+func TestTheObjectsALatestDeclarationNamesAreReadFromTheBus(t *testing.T) {
+	s := sendable{fileReferences: true, Resources: []map[string]any{aFileResource("a", contentOf("a", 70<<10))}}
+	body, _ := s.Body()
+	msg, _ := link.Envelope(body, []byte("sig"))
+	named, err := namedByLatest("novox", msg)
+	name, _ := sdkdecl.ObjectName(sdkdecl.DigestOf([]byte(contentOf("a", 70<<10))))
+	if err != nil || len(named) != 1 || !named[name] {
+		t.Fatalf("%v %v", named, err)
+	}
+	if none, err := namedByLatest("ace", []byte(`{"declaration":"e30=","signature":""}`)); err != nil || len(none) != 0 {
+		t.Fatalf("a declaration naming none: %v %v", none, err)
+	}
+	if _, err := namedByLatest("novox", []byte("not json")); err == nil {
+		t.Fatal("an unreadable latest declaration was read as naming none")
+	}
+}
+
+// 1698/AC2 (ADR 0486 §9): a declaration shaped like the control node's, for a node that reads references, stays under half of the
+// bus's largest message on the wire; the inline form of the same does not fit at all; and the same shape with 40 percent more resources
+// fails the test's own limit, so a change that eats the room fails in a pull request and not on the live mesh.
+func TestTheControlNodesDeclarationInTheReferenceFormStaysUnderHalfTheBusLimit(t *testing.T) { // 1698/AC2
+	const limit = 1048576
+	shape := sendable{fileReferences: true, Resources: controlNodeShape(1)}
+	n := wireSizeOf(t, shape)
+	t.Logf("the control node's shape in the reference form: %d bytes on the wire, %.1f%% of %d", n, 100*float64(n)/limit, limit)
+	if n > limit/2 {
+		t.Errorf("the reference form is %d bytes on the wire, over half (%d) of the bus's largest message", n, limit/2)
+	}
+	if inline := wireSizeOf(t, sendable{Resources: controlNodeShape(1)}); inline < limit*3/4 {
+		t.Errorf("the inline form is %d bytes, which is not the shape that was over the limit", inline)
+	}
+	grown := wireSizeOf(t, sendable{fileReferences: true, Resources: controlNodeShape(1.4)})
+	if grown <= limit/2 {
+		t.Errorf("the shape with 40%% more resources is %d bytes, which the test would let pass", grown)
+	}
+}
+
+func stdBase64(b []byte) string { return base64.StdEncoding.EncodeToString(b) }
+
+// A sweep that read an object's mark before a send put it again must not remove it: the object, now without the mark, is left.
+func TestASweepDoesNotRemoveAnObjectASendPutAgainAfterItWasJudged(t *testing.T) { // 1696/AC8
+	n := strings.Repeat("4", 64)
+	t0 := time.Date(2026, 10, 21, 12, 0, 0, 0, time.UTC)
+	b := &sweepBucketFake{objects: map[string]time.Time{n: t0}}
+	judged := bucketObject{Name: n, UnnamedSince: t0}
+	b.objects[n] = time.Time{} // the send put it again: no mark
+	if gone, err := b.Delete(t.Context(), judged.Name, judged.UnnamedSince); err != nil || gone || len(b.deleted) != 0 {
+		t.Fatalf("an object put again was removed: %v %v %v", gone, err, b.deleted)
+	}
+}
+
+// One node's bucket is held by one act at a time in this process: the sweep waits for a send that has put its objects and not yet
+// published the declaration that names them (1696/AC9).
+func TestTheSweepOfANodesBucketWaitsForASendThatHasPutItsObjects(t *testing.T) { // 1696/AC9
+	unlock := lockFilesOf("lock-test-node")
+	got := make(chan struct{})
+	go func() {
+		defer lockFilesOf("lock-test-node")()
+		close(got)
+	}()
+	select {
+	case <-got:
+		t.Fatal("the sweep took the node's bucket while a send held it")
+	case <-time.After(50 * time.Millisecond):
+	}
+	other := lockFilesOf("lock-test-other-node") // another node's bucket is not held
+	other()
+	unlock()
+	select {
+	case <-got:
+	case <-time.After(2 * time.Second):
+		t.Fatal("the sweep did not take the node's bucket once the send was done")
+	}
+}
+
+// A put that fails send after send raises a condition; the first failure does not (the grant it waits for travels in that very
+// declaration), and a put that works clears it (1696/AC10).
+func TestAPutThatFailsSendAfterSendRaisesAConditionAndClearsWhenItWorks(t *testing.T) { // 1696/AC10
+	store := conditions.NewInMemory()
+	k := conditions.NewKeeper(t.Context(), conditions.Options{Store: store, History: store,
+		Teller: &conditions.Told{}, Now: func() time.Time { return time.Date(2026, 10, 21, 14, 0, 0, 0, time.UTC) }})
+	t.Cleanup(func() { k.Close(t.Context()) })
+	was := conditionsFrom
+	conditionsFrom = k
+	t.Cleanup(func() { conditionsFrom = was })
+	key := filesNotPutObservation("cond-node", "").Key()
+	open := func() bool {
+		_, found, err := conditions.ReadOne(t.Context(), store, key)
+		if err != nil {
+			t.Fatal(err)
+		}
+		return found
+	}
+	boom := errors.New("permissions violation")
+	notePut(t.Context(), "cond-node", boom)
+	if open() {
+		t.Fatal("the first failure raised the condition")
+	}
+	notePut(t.Context(), "cond-node", boom)
+	if !open() {
+		t.Fatal("the second failure in a row did not raise the condition")
+	}
+	notePut(t.Context(), "cond-node", nil)
+	if open() {
+		t.Fatal("a put that worked did not clear the condition")
+	}
+	notePut(t.Context(), "cond-node", boom)
+	if open() {
+		t.Fatal("the count did not start again after a put that worked")
+	}
+}
+
+// aBusThatSays is a bus that keeps the declarations published to it and, at each, asks whether the node's bucket is held.
+type aBusThatSays struct {
+	link.Bus
+	published     chan string
+	heldAtPublish func() bool
+}
+
+func (b *aBusThatSays) PublishDeclaration(_ context.Context, node string, _ []byte) error {
+	if b.heldAtPublish != nil && !b.heldAtPublish() {
+		return errors.New("published while the node's bucket was not held")
+	}
+	b.published <- node
+	return errors.New("stop here: nothing is recorded")
+}
+
+type aSignerOfZeros struct{}
+
+func (aSignerOfZeros) Sign(context.Context, []byte) ([]byte, error) { return make([]byte, 64), nil }
+
+// whileHeld says whether the node's lock is held by someone right now, without keeping it.
+func whileHeld(node string) bool {
+	got := make(chan struct{})
+	go func() {
+		defer lockFilesOf(node)()
+		close(got)
+	}()
+	select {
+	case <-got:
+		return false
+	case <-time.After(100 * time.Millisecond):
+		// held: the goroutine stays waiting and takes and releases the lock once it is let go.
+		return true
+	}
+}
+
+// 1696/AC9: a send holds the node's lock from the put to the publication, so the sweep never removes an object between them. The
+// test goes through overTheBus.declare: while another holds the lock the declaration is not published, and at the publication the
+// lock is held.
+func TestASendHoldsTheNodesLockFromThePutToThePublication(t *testing.T) { // 1696/AC9
+	const node = "lock-send-node"
+	bus := &aBusThatSays{published: make(chan string, 1)}
+	bus.heldAtPublish = func() bool { return whileHeld(node) }
+	send := overTheBus{server: link.SendingOn(bus), signer: aSignerOfZeros{}}
+	release := lockFilesOf(node) // a sweep is judging this node's bucket
+	done := make(chan error, 1)
+	go func() {
+		_, err := send.declare(t.Context(), readyNode{node: node}, []byte(`{}`))
+		done <- err
+	}()
+	select {
+	case n := <-bus.published:
+		t.Fatalf("%s was sent its declaration while the sweep held the node's bucket", n)
+	case <-time.After(150 * time.Millisecond):
+	}
+	release()
+	select {
+	case <-bus.published:
+	case <-time.After(5 * time.Second):
+		t.Fatal("the send did not go on once the sweep let go")
+	}
+	if err := <-done; err == nil || !strings.Contains(err.Error(), "nothing is recorded") {
+		t.Fatalf("the send did not reach the publication (a lock held at it): %v", err)
+	}
+}

cmd/mesh-controller/declaration_room.go

@@ -13,8 +13,8 @@ import (
 
 // **A declaration is one bus message, and the bus's largest message is a cliff** (novox/hq issue 1689). On 2026-10-21
 // the control node's declaration passed it by 2 KB and nothing reached that node until two assignments were undone.
-// So the size is measured at every send: a warning condition from 90% of the limit, urgent over it, cleared when
-// the declaration is back under 90%. The limit is the connection's own, not a constant.
+// So the size is measured at every send: a warning condition from 75% of the limit (ADR 0486 §8, issue 1698: it was 90% while every file travelled inline), urgent over it, cleared when
+// the declaration is back under 75%. The limit is the connection's own, not a constant.
 
 // kindDeclarationNearLimit is a declaration at or near the bus's largest message.
 const kindDeclarationNearLimit = "declaration-near-limit"

cmd/mesh-controller/declaration_room_test.go

@@ -33,7 +33,7 @@ func TestTheVaultsExportIsSentCompactAndNothingElseIsTouched(t *testing.T) {
 	}
 }
 
-// From 90% of the bus's largest message the declaration is a warning; over it, urgent; back under 90%, cleared.
+// From 75% of the bus's largest message (ADR 0486 §8, issue 1698) the declaration is a warning; over it, urgent; back under 75%, cleared.
 func TestADeclarationNearTheBusLimitRaisesAConditionAndClearsWhenSmaller(t *testing.T) {
 	store := conditions.NewInMemory()
 	k := conditions.NewKeeper(t.Context(), conditions.Options{Store: store, History: store,
@@ -50,22 +50,22 @@ func TestADeclarationNearTheBusLimitRaisesAConditionAndClearsWhenSmaller(t *test
 		return c, found
 	}
 
-	settleDeclarationRoom(t.Context(), k, "novox", 899, limit)
+	settleDeclarationRoom(t.Context(), k, "novox", 749, limit)
 	if _, found := read(); found {
-		t.Fatal("a declaration at 89.9% raised a condition")
+		t.Fatal("a declaration at 74.9% raised a condition")
 	}
-	settleDeclarationRoom(t.Context(), k, "novox", 900, limit)
+	settleDeclarationRoom(t.Context(), k, "novox", 750, limit)
 	c, found := read()
-	if !found || c.Severity != conditions.Warning || !strings.Contains(c.Summary, "900 bytes") ||
+	if !found || c.Severity != conditions.Warning || !strings.Contains(c.Summary, "750 bytes") ||
 		!strings.Contains(c.Summary, "1000") || c.Subject.Machine != "novox" {
-		t.Fatalf("at 90%% the condition is %v %+v", found, c)
+		t.Fatalf("at 75%% the condition is %v %+v", found, c)
 	}
 	settleDeclarationRoom(t.Context(), k, "novox", 1001, limit)
 	if c, _ := read(); c.Severity != conditions.Urgent {
 		t.Fatalf("over the limit the condition is %q, expected urgent", c.Severity)
 	}
-	settleDeclarationRoom(t.Context(), k, "novox", 850, limit)
+	settleDeclarationRoom(t.Context(), k, "novox", 700, limit)
 	if _, found := read(); found {
-		t.Fatal("the condition stayed after the declaration fell under 90%")
+		t.Fatal("the condition stayed after the declaration fell under 75%")
 	}
 }

cmd/mesh-controller/declaration_sweep.go

@@ -0,0 +1,273 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"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"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// **An object is removed a day after no node's latest declaration names it** (novox/hq ADR 0486 §3, issue 1696), so a node that is
+// asleep and receives its latest declaration later still finds every object that declaration names. What each node's latest
+// declaration names is read from the bus itself, the last message of that node's subject of the stream NODES: nothing else
+// is kept of it. When an object is first found named by none, the time is written in its own metadata (declarationUnnamed);
+// found named again, that is erased; found unnamed for a day, it is removed. Each node has a bucket of its own, judged against that
+// node's latest declaration alone. Objects are immutable and regenerable from the
+// controller's state, so a removal loses nothing.
+
+// declarationUnnamed is the key of an object's metadata holding when it was first found named by no node's latest declaration.
+const declarationUnnamed = "unnamed-since"
+
+// sweepEvery is how often the bucket is judged: the removal is exact to within this.
+const sweepEvery = time.Hour
+
+// bucketObject is one object of the bucket as the sweep sees it.
+type bucketObject struct {
+	Name string
+	// UnnamedSince is when it was first found named by none, zero when it was named at the last look.
+	UnnamedSince time.Time
+}
+
+// sweptBucket is what the sweep needs of the bucket.
+type sweptBucket interface {
+	Objects(ctx context.Context) ([]bucketObject, error)
+	MarkUnnamed(ctx context.Context, name string, since time.Time) error
+	ClearUnnamed(ctx context.Context, name string) error
+	// Delete removes the object if it still carries the mark it was judged by, and says whether it did: a send that put it again
+	// since has erased the mark, and the object is left.
+	Delete(ctx context.Context, name string, markedAt time.Time) (bool, error)
+}
+
+// filesSweep says what a sweep did.
+type filesSweep struct{ Kept, Marked, Cleared, Removed int }
+
+// sweepDeclarationFiles judges every object against the names of the latest declarations: named ones are kept (and a
+// mark of being unnamed is erased), unnamed ones are marked at the first look and removed once the mark is a day old.
+func sweepDeclarationFiles(ctx context.Context, bucket sweptBucket, named map[string]bool, now time.Time) (filesSweep, error) {
+	var r filesSweep
+	objects, err := bucket.Objects(ctx)
+	if err != nil {
+		return r, err
+	}
+	sort.Slice(objects, func(i, j int) bool { return objects[i].Name < objects[j].Name })
+	for _, o := range objects {
+		switch {
+		case named[o.Name]:
+			r.Kept++
+			if !o.UnnamedSince.IsZero() {
+				if err := bucket.ClearUnnamed(ctx, o.Name); err != nil {
+					return r, fmt.Errorf("the object %s: %w", o.Name[:12], err)
+				}
+				r.Cleared++
+			}
+		case o.UnnamedSince.IsZero():
+			if err := bucket.MarkUnnamed(ctx, o.Name, now); err != nil {
+				return r, fmt.Errorf("the object %s: %w", o.Name[:12], err)
+			}
+			r.Marked++
+		case now.Sub(o.UnnamedSince) >= broker.DeclarationFilesKeptFor:
+			gone, err := bucket.Delete(ctx, o.Name, o.UnnamedSince)
+			if err != nil {
+				return r, fmt.Errorf("the object %s: %w", o.Name[:12], err)
+			}
+			if gone {
+				r.Removed++
+			} else {
+				r.Kept++
+			}
+		default:
+			r.Kept++
+		}
+	}
+	return r, nil
+}
+
+// namedByLatest is the name of every object this latest declaration of a node names. A body that cannot be read is an error, never
+// "names none": an object the node still needs would be marked for removal.
+func namedByLatest(node string, signed []byte) (map[string]bool, error) {
+	var s link.Signed
+	if err := json.Unmarshal(signed, &s); err != nil {
+		return nil, fmt.Errorf("%s's latest declaration is not readable: %w", node, err)
+	}
+	names, err := namedObjects(s.Declaration)
+	if err != nil {
+		return nil, fmt.Errorf("%s's latest declaration is not readable: %w", node, err)
+	}
+	named := make(map[string]bool, len(names))
+	for name := range names {
+		named[name] = true
+	}
+	return named, nil
+}
+
+// latestDeclarations are the last signed declarations of the nodes, by node, as the stream NODES holds them. A node with none has
+// no entry.
+func latestDeclarations(ctx context.Context, conn *nats.Conn, nodes []string) (map[string][]byte, error) {
+	js, err := conn.JetStream(nats.Context(ctx))
+	if err != nil {
+		return nil, err
+	}
+	out := map[string][]byte{}
+	for _, node := range nodes {
+		msg, err := js.GetLastMsg("NODES", link.DeclareSubject(node), nats.Context(ctx))
+		if errors.Is(err, nats.ErrMsgNotFound) {
+			continue
+		}
+		if err != nil {
+			return nil, fmt.Errorf("the latest declaration of %s: %w", node, err)
+		}
+		out[node] = msg.Data
+	}
+	return out, nil
+}
+
+// busSweptBucket is the bucket on the controller's connection.
+type busSweptBucket struct{ store jetstream.ObjectStore }
+
+func (b busSweptBucket) Objects(ctx context.Context) ([]bucketObject, error) {
+	infos, err := b.store.List(ctx)
+	if errors.Is(err, jetstream.ErrNoObjectsFound) {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	out := make([]bucketObject, 0, len(infos))
+	for _, info := range infos {
+		o := bucketObject{Name: info.Name}
+		if at, err := time.Parse(time.RFC3339, info.Metadata[declarationUnnamed]); err == nil {
+			o.UnnamedSince = at
+		}
+		out = append(out, o)
+	}
+	return out, nil
+}
+
+func (b busSweptBucket) meta(ctx context.Context, name string, change func(map[string]string)) error {
+	info, err := b.store.GetInfo(ctx, name)
+	if err != nil {
+		return err
+	}
+	meta := info.ObjectMeta
+	kept := map[string]string{}
+	for k, v := range meta.Metadata {
+		kept[k] = v
+	}
+	change(kept)
+	meta.Metadata = kept
+	return b.store.UpdateMeta(ctx, name, meta)
+}
+
+func (b busSweptBucket) MarkUnnamed(ctx context.Context, name string, since time.Time) error {
+	return b.meta(ctx, name, func(m map[string]string) { m[declarationUnnamed] = since.UTC().Format(time.RFC3339) })
+}
+
+func (b busSweptBucket) ClearUnnamed(ctx context.Context, name string) error {
+	return b.meta(ctx, name, func(m map[string]string) { delete(m, declarationUnnamed) })
+}
+
+func (b busSweptBucket) Delete(ctx context.Context, name string, markedAt time.Time) (bool, error) {
+	info, err := b.store.GetInfo(ctx, name)
+	if errors.Is(err, jetstream.ErrObjectNotFound) {
+		return false, nil
+	}
+	if err != nil {
+		return false, err
+	}
+	if at, perr := time.Parse(time.RFC3339, info.Metadata[declarationUnnamed]); perr != nil || !at.Equal(markedAt) {
+		return false, nil
+	}
+	return true, b.store.Delete(ctx, name)
+}
+
+// sweepingDeclarationFiles judges the bucket every sweepEvery for as long as this controller serves and holds the lease.
+func sweepingDeclarationFiles(ctx context.Context, inv *inventory.Inventory, conn *nats.Conn) {
+	tick := time.NewTicker(sweepEvery)
+	defer tick.Stop()
+	failing := ""
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-tick.C:
+		}
+		if epoch, err := theLease.epoch(ctx); err != nil || epoch == 0 {
+			continue
+		}
+		why := sweepOnce(ctx, inv, conn)
+		if why != failing {
+			if why != "" {
+				fmt.Printf("the bucket of declaration files cannot be swept: %s\n", why)
+			} else {
+				fmt.Printf("the bucket of declaration files is swept again\n")
+			}
+			failing = why
+		}
+	}
+}
+
+// sweepOnce judges the bucket of every node against that node's latest declaration, one bucket at a time under the node's lock, with
+// the declaration read again under it: a send that put an object and published its declaration is seen, and one that has not yet
+// is waiting for the lock.
+func sweepOnce(ctx context.Context, inv *inventory.Inventory, conn *nats.Conn) string {
+	nodes, err := inv.Nodes(ctx)
+	if err != nil {
+		return fmt.Sprintf("the nodes cannot be read: %v", err)
+	}
+	var problems []string
+	var total filesSweep
+	for _, n := range nodes {
+		r, err := sweepNode(ctx, conn, n.Name)
+		total.Kept, total.Marked, total.Cleared, total.Removed = total.Kept+r.Kept, total.Marked+r.Marked, total.Cleared+r.Cleared, total.Removed+r.Removed
+		if err != nil {
+			problems = append(problems, fmt.Sprintf("%s: %v", n.Name, err))
+		}
+	}
+	if total.Removed+total.Marked+total.Cleared > 0 {
+		fmt.Printf("the buckets of declaration files: %d object(s) kept, %d found unnamed, %d named again, %d removed\n",
+			total.Kept, total.Marked, total.Cleared, total.Removed)
+	}
+	return strings.Join(problems, "; ")
+}
+
+func sweepNode(ctx context.Context, conn *nats.Conn, node string) (filesSweep, error) {
+	working, cancel := context.WithTimeout(ctx, 2*time.Minute)
+	defer cancel()
+	js, err := jetstream.New(conn)
+	if err != nil {
+		return filesSweep{}, err
+	}
+	bucket, err := broker.DeclarationFilesBucketOf(node)
+	if err != nil {
+		return filesSweep{}, fmt.Errorf("the bucket of node %q: %w", node, err)
+	}
+	store, err := js.ObjectStore(working, bucket)
+	if errors.Is(err, jetstream.ErrBucketNotFound) {
+		return filesSweep{}, nil // a node never sent a reference has no bucket yet
+	}
+	if err != nil {
+		return filesSweep{}, fmt.Errorf("the bucket cannot be read: %w", err)
+	}
+	defer lockFilesOf(node)()
+	latest, err := latestDeclarations(working, conn, []string{node})
+	if err != nil {
+		return filesSweep{}, err
+	}
+	named := map[string]bool{}
+	if body, ok := latest[node]; ok {
+		if named, err = namedByLatest(node, body); err != nil {
+			return filesSweep{}, err
+		}
+	}
+	return sweepDeclarationFiles(working, busSweptBucket{store}, named, time.Now())
+}

cmd/mesh-controller/plain_words.go

@@ -195,6 +195,14 @@ var plainWordings = map[string]func(conditions.Observation) words{
 				"there yet is sealed by the controller until the vault holds it.", m, m),
 			Resolved: "Resolved: the vault gave " + m + " the core's credentials"}
 	}),
+	kindFilesNotPut: worded(func(o conditions.Observation) words {
+		m := machineOr(o, "a machine")
+		return words{Headline: "The big files for " + m + " cannot be put on the bus",
+			Needs: "look at the bus's permissions for the controller; the details give the reason.",
+			Explanation: fmt.Sprintf("The mesh could not put the large files of %s's instructions in their place on the bus, "+
+				"send after send, so %s is sent them inside the instructions instead, which may make them too big.", m, m),
+			Resolved: "Resolved: the big files for " + m + " reach the bus again"}
+	}),
 	kindDeclarationNearLimit: worded(func(o conditions.Observation) words {
 		m := machineOr(o, "a machine")
 		if o.Severity == conditions.Urgent {

cmd/mesh-controller/push.go

@@ -282,6 +282,8 @@ func serve(ctx context.Context) (err error) {
 	// assignment.
 	inv.SetProvisioningPlans(inv.SentProvisioningPlans)
 	go mirroringRecords(ctx, inv, bus.Conn, bus)
+	// And the bucket of the files that travel by digest, judged against what each machine's latest declaration names (ADR 0486 §3).
+	go sweepingDeclarationFiles(ctx, inv, bus.Conn)
 	// Every call carries the lease's epoch, and its record is written only under the lease (novox/hq
 	// to-be 45 §6).
 	link.Calls.UnderLease(func() (uint64, error) { return theLease.epoch(ctx) })
@@ -979,6 +981,18 @@ func deliver(ctx context.Context, d delivery, holder string, sending []readyNode
 			return err
 		}
 		digest, err := d.declare(ctx, s, body)
+		if errors.Is(err, errFilesNotPut) && s.declared.fileReferences {
+			// **The grant that lets the controller write the bucket travels in the very declaration of the machine holding the
+			// bus** (novox/hq ADR 0486 §2): until the bus has it, a put is refused, and the declaration that would deliver the
+			// grant would wait for it. So that send, and only that, goes with every content inline, as to a node that reads no
+			// references, and says so; the next one tries the bucket again.
+			fmt.Printf("%s: the files that travel by digest could not be put in the bucket (%v): sending them inline\n", s.node, err)
+			s.declared.fileReferences = false
+			if body, err = s.declared.Body(); err != nil {
+				return err
+			}
+			digest, err = d.declare(ctx, s, body)
+		}
 		if err != nil {
 			return err
 		}
@@ -1040,6 +1054,35 @@ type overTheBus struct {
 	indent string
 }
 
+// putFiles puts the contents s names by digest in the bucket.
+func (b overTheBus) putFiles(ctx context.Context, s readyNode) error {
+	objects, err := s.declared.objects()
+	if err != nil {
+		return fmt.Errorf("%s: the files that travel by digest cannot be read: %w", s.node, err)
+	}
+	if len(objects) == 0 {
+		return nil
+	}
+	bus, ok := b.server.Bus().(link.OverNATS)
+	if !ok {
+		return fmt.Errorf("%s: the declaration names files by digest and this bus has no object bucket", s.node)
+	}
+	putting, cancel := context.WithTimeout(ctx, 30*time.Second)
+	defer cancel()
+	store, err := openBucket(putting, bus.Conn, s.node)
+	if err == nil {
+		err = putObjects(putting, store, objects)
+	}
+	notePut(ctx, s.node, err)
+	if err != nil {
+		return fmt.Errorf("%s was not sent its declaration: %w: %w", s.node, errFilesNotPut, err)
+	}
+	return nil
+}
+
+// errFilesNotPut marks a send that stopped because the files it names by digest could not be put in the bucket.
+var errFilesNotPut = errors.New("the files it names by digest are not in the bucket")
+
 func (b overTheBus) grant(ctx context.Context, sending []readyNode) error {
 	// The bus's objects first, which every declaration implies (novox/hq issue 208): said and raised
 	// when they cannot be, and never what holds the send back (assertOnSend).
@@ -1052,9 +1095,20 @@ func (b overTheBus) grant(ctx context.Context, sending []readyNode) error {
 }
 
 func (b overTheBus) declare(ctx context.Context, s readyNode, body []byte) (string, error) {
-	if err := link.Declare(ctx, b.server.Bus(), b.signer, s.node, body, 15*time.Second); err != nil {
+	// The contents the declaration names by digest are in the bucket before it is sent (novox/hq ADR 0486 §1, issue 1696): a node
+	// that applies it finds every one. A node reading no references has none.
+	// **Under the node's lock** from the put to the publication, so the sweep of its bucket cannot remove an object between them.
+	unlock := lockFilesOf(s.node)
+	err := b.putFiles(ctx, s)
+	if err != nil {
+		unlock()
 		return "", err
 	}
+	declared := link.Declare(ctx, b.server.Bus(), b.signer, s.node, body, 15*time.Second)
+	unlock()
+	if declared != nil {
+		return "", declared
+	}
 	// After it is away, not before. A digest recorded for something that failed to send would make
 	// the machine look current for a declaration it never received.
 	digest, err := recordSent(ctx, b.open.inventory, s.node, body, s.declared.Builds, s.declared.Epoch,

cmd/mesh-controller/sendable.go

@@ -39,6 +39,10 @@ type sendable struct {
 	// ReadsModules says the machine's node-engine reads a module per resource and a build per module (novox/hq issue
 	// 1145): only then are they sent, because an older node-engine refuses a key it does not know, whole.
 	ReadsModules bool
+	// fileReferences says the machine's node-engine reports the capability of reading a file given as a digest and a size
+	// (declaration.FileReferencesCapability, novox/hq ADR 0486 §5): then every file over 64 KiB that may travel so does (Body,
+	// objects). Not on the wire as a field; the bodies differ.
+	fileReferences bool
 	// moduleOf is the composer's owner of each resource id, and buildIDs the build each module carries (its id):
 	// kept beside the resources, and on the wire only to a machine that reads them.
 	moduleOf map[string]string
@@ -115,12 +119,16 @@ type adoptionEnvelope struct {
 
 // Body is the declaration's bytes, as sent and as digested.
 func (s sendable) Body() ([]byte, error) {
-	envelope := map[string]any{"declaration": 1, "resources": s.Resources}
+	resources, _, err := s.byReference()
+	if err != nil {
+		return nil, err
+	}
+	envelope := map[string]any{"declaration": 1, "resources": resources}
 	if s.ReadsModules {
 		// The module of each resource the composer owns (what the mesh adds of its own has none), and the build of each
 		// module (novox/hq issue 1145): to a machine that said it reads them, and no other.
-		named := make([]map[string]any, len(s.Resources))
-		for n, r := range s.Resources {
+		named := make([]map[string]any, len(resources))
+		for n, r := range resources {
 			module, owned := s.moduleOf[fmt.Sprint(r["id"])]
 			if !owned {
 				named[n] = r
@@ -165,3 +173,19 @@ func (s sendable) Body() ([]byte, error) {
 	}
 	return json.Marshal(envelope)
 }
+
+// byReference is the resources as the machine is sent them: with the contents of its large files replaced by their digests when
+// it reports it reads them (issue 1696), and the contents it replaced, by the name of the object that holds each.
+func (s sendable) byReference() ([]map[string]any, map[string][]byte, error) {
+	if !s.fileReferences {
+		return s.Resources, nil, nil
+	}
+	return referencing(s.Resources)
+}
+
+// objects are the contents the body names by digest, by the name of each one's object: what is put in the bucket before the
+// body is sent. Empty for a machine that is sent every content inline.
+func (s sendable) objects() (map[string][]byte, error) {
+	_, objects, err := s.byReference()
+	return objects, err
+}

go.mod

@@ -3,7 +3,7 @@ module github.com/novox/mesh-controller
 go 1.26.0
 
 require (
-	git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261021093645-465beb4ea5e3
+	git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261021134822-86f9a1a5c508
 	github.com/jackc/pgx/v5 v5.10.0
 	github.com/nats-io/nats-server/v2 v2.11.17
 	github.com/nats-io/nats.go v1.54.0

go.sum

@@ -2,6 +2,10 @@ git.novox.be/novox/mesh-host v0.0.0-20261018171808-9d9e3a46c4f5 h1:E5stfIeCN6uYg
 git.novox.be/novox/mesh-host v0.0.0-20261018171808-9d9e3a46c4f5/go.mod h1:4wyoCr6IIIIarEUuROThWDj7DAvJvIidqMjWcpSnOwE=
 git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261021093645-465beb4ea5e3 h1:OKxU64kHN1yQ/GOa6LwoUwVmiQ74d83WMSZJRFPVm9c=
 git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261021093645-465beb4ea5e3/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261021124357-863a981e014e h1:eq29ENikw3XfEXjxL5OdnTbavv5pu1/UnQhWWuf5V5I=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261021124357-863a981e014e/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261021134822-86f9a1a5c508 h1:nTQN4W6gfIUR0fLpA1IYb06TGr3MtuW0xtznjbcMGLM=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261021134822-86f9a1a5c508/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
 github.com/antithesishq/antithesis-sdk-go v0.7.0-default-no-op h1:Z/MZK75wC/NSrkgqeNIa7jexam9uWzhLmFTSCPI/kn0=
 github.com/antithesishq/antithesis-sdk-go v0.7.0-default-no-op/go.mod h1:FQyySiasQQM8735Ddel3MRojmy4dA1IqCeyJ5jmPMbI=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=

internal/broker/declaration_files.go

@@ -0,0 +1,123 @@
+package broker
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"git.novox.be/novox/mesh-sdk/go/declaration"
+	"github.com/nats-io/nats.go/jetstream"
+)
+
+// The object buckets a declaration's large files travel in (novox/hq ADR 0486, issues 1696 and 1697): **one bucket for each
+// node**, `declaration-files-<node>`.
+//
+// **The controller alone writes them, and a node-engine reads an object by its name from its own bucket** (ADR 0486 §2): its
+// account may neither list the bucket nor write it, no account may touch another node's, and no other account has any access.
+// Why a bucket each: a subject pattern cannot tell a name from a wildcard. A grant of `...M.*` matches a publish to the literal
+// subject `...M.*` too (probed on nats-server 2.11.17 by the review of this issue: a node created a consumer filtered on
+// `$O.<bucket>.C.*` and read every object of the bucket), so in one shared bucket a node could read every other node's files.
+// With a bucket each, the same trick reads only the node's own files, which are the files of its own declaration.
+//
+// A bucket of the bus's object store is a stream, OBJ_<bucket>, whose messages are the objects' metadata
+// (`$O.<bucket>.M.<base64 of the name>`) and chunks (`$O.<bucket>.C.<nuid>`).
+
+// DeclarationFilesBucket is the prefix of the buckets' names, which mesh-sdk fixes for the node-engine and the controller alike.
+const DeclarationFilesBucket = declaration.FileBucketPrefix
+
+// DeclarationFilesBucketOf is the bucket a node's files are in: mesh-sdk's FileBucketFor, the one place the name is composed. A
+// node name it refuses (one that could carry a subject wildcard or separator into a grant) is an error, never a bucket.
+func DeclarationFilesBucketOf(node string) (string, error) { return declaration.FileBucketFor(node) }
+
+// DeclarationFilesStreamOf is the stream under a node's bucket: mesh-sdk's FileStreamFor.
+func DeclarationFilesStreamOf(node string) (string, error) { return declaration.FileStreamFor(node) }
+
+// DeclarationFilesMaxBytes is a bucket's size: the objects are immutable and regenerable, and one node's hold well under a hundred
+// megabytes.
+const DeclarationFilesMaxBytes = 1 << 30
+
+// DeclarationFilesKeptFor is how long an object stays after no node's latest declaration names it (ADR 0486 §3).
+const DeclarationFilesKeptFor = 24 * time.Hour
+
+// DeclarationFilesWrites is the one pattern the controller may publish to write a node's bucket: every object's metadata and
+// chunks. The server's API for the stream is the controller's `$JS.API.>`.
+func DeclarationFilesWrites(node string) (string, error) {
+	bucket, err := DeclarationFilesBucketOf(node)
+	if err != nil {
+		return "", err
+	}
+	return "$O." + bucket + ".>", nil
+}
+
+// DeclarationFilesReads is what a node-engine's account may publish to read an object of its own bucket by its name, and nothing
+// more. The set is the one node-engine's own call (mesh-host internal/link FileObject) makes, for B the node's bucket and S its
+// stream (issue 1697, notes 4 and 5):
+//
+//   - the object's metadata, by a direct get of the last message of the one subject that names it. **Only the suffixed
+//     form**: the bare `$JS.API.DIRECT.GET.S` takes a sequence number and would read any message of the stream.
+//   - the ordered consumer on that object's chunks: `$JS.API.CONSUMER.CREATE.S.<name>.$O.B.C.<nuid>`. **Not `S.>`**:
+//     a consumer filtered on `$O.B.M.>` would read every object's name.
+//   - the flow-control replies of that consumer, without which a large object stalls at the flow-control window.
+//   - the consumer's deletion, best effort: the consumer's inactivity threshold removes it if this is refused.
+//
+// **Never granted:** STREAM.INFO (a `subjects_filter` of `>` lists every name), STREAM.MSG.GET (any message by its sequence), a
+// publish to `$O.B.>` (a write), and any subject of another node's stream. A literal `*` in a subject matches the grant's `*`: it
+// reaches the objects of this node's own bucket and no other (above).
+func DeclarationFilesReads(node string) ([]string, error) {
+	bucket, err := DeclarationFilesBucketOf(node)
+	if err != nil {
+		return nil, err
+	}
+	stream, err := DeclarationFilesStreamOf(node)
+	if err != nil {
+		return nil, err
+	}
+	return []string{
+		"$JS.API.DIRECT.GET." + stream + ".$O." + bucket + ".M.*",
+		"$JS.API.CONSUMER.CREATE." + stream + ".*.$O." + bucket + ".C.*",
+		"$JS.API.CONSUMER.DELETE." + stream + ".*",
+		"$JS.FC." + stream + ".>",
+	}, nil
+}
+
+// EnsureDeclarationFiles creates the buckets of these nodes if absent and brings their options to match. A bucket exists whenever the
+// bus does, so a node that is starting finds it (ADR 0486 §4). An update, never a delete.
+func (j *JetStream) EnsureDeclarationFiles(nodes []string) error {
+	js, err := jetstream.New(j.conn)
+	if err != nil {
+		return err
+	}
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+	return EnsureDeclarationFiles(ctx, js, nodes...)
+}
+
+// EnsureDeclarationFiles is the same on a JetStream the caller holds.
+func EnsureDeclarationFiles(ctx context.Context, js jetstream.JetStream, nodes ...string) error {
+	for _, node := range nodes {
+		cfg, err := DeclarationFilesConfig(node)
+		if err != nil {
+			return err
+		}
+		if _, err := js.CreateOrUpdateObjectStore(ctx, cfg); err != nil {
+			return fmt.Errorf("asserting the object bucket %s: %w", cfg.Bucket, err)
+		}
+	}
+	return nil
+}
+
+// DeclarationFilesConfig is a node's bucket as the controller asserts it.
+func DeclarationFilesConfig(node string) (jetstream.ObjectStoreConfig, error) {
+	bucket, err := DeclarationFilesBucketOf(node)
+	if err != nil {
+		return jetstream.ObjectStoreConfig{}, err
+	}
+	return jetstream.ObjectStoreConfig{
+		Bucket: bucket,
+		Description: "the contents of the files over 64 KiB of the declaration of " + node + ", each under the hex of its sha256 " +
+			"digest (novox/hq ADR 0486): written by the controller alone, read by the node-engine of that node by name, removed " +
+			"a day after the node's latest declaration no longer names it",
+		MaxBytes: DeclarationFilesMaxBytes,
+		Storage:  jetstream.FileStorage,
+	}, nil
+}

internal/broker/declaration_files_live_test.go

@@ -0,0 +1,316 @@
+//go:build integration
+
+package broker
+
+import (
+	"bytes"
+	"context"
+	"crypto/sha256"
+	"encoding/base64"
+	"encoding/hex"
+	"encoding/json"
+	"errors"
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+
+	"github.com/nats-io/nats-server/v2/server"
+	"github.com/nats-io/nats.go"
+	"github.com/nats-io/nats.go/jetstream"
+	"golang.org/x/crypto/bcrypt"
+)
+
+// nodeEnginesFileObject is the node-engine's own call (mesh-host internal/link files.go, OverNATS.FileObject), as the
+// engine makes it: the object's metadata by a direct get of one subject, then its chunks through an ordered consumer
+// bound to the stream. It is copied here so the grants are judged by the call that has to work, and its subjects are the
+// ones the grant names (issue 1697, notes 4 and 5); the node-engine's own integration test holds the other copy.
+func nodeEnginesFileObject(ctx context.Context, nc *nats.Conn, node, name string) ([]byte, error) {
+	js, err := nc.JetStream(nats.MaxWait(10 * time.Second))
+	if err != nil {
+		return nil, err
+	}
+	stream, err := DeclarationFilesStreamOf(node)
+	if err != nil {
+		return nil, err
+	}
+	bucket, err := DeclarationFilesBucketOf(node)
+	if err != nil {
+		return nil, err
+	}
+	meta, err := js.GetLastMsg(stream, "$O."+bucket+".M."+base64.URLEncoding.EncodeToString([]byte(name)),
+		nats.DirectGet(), nats.Context(ctx))
+	if err != nil {
+		return nil, err
+	}
+	var info struct {
+		NUID string `json:"nuid"`
+		Size uint64 `json:"size"`
+	}
+	if err := json.Unmarshal(meta.Data, &info); err != nil {
+		return nil, err
+	}
+	sub, err := js.SubscribeSync("$O."+bucket+".C."+info.NUID, nats.OrderedConsumer(), nats.BindStream(stream))
+	if err != nil {
+		return nil, err
+	}
+	defer sub.Unsubscribe()
+	body := make([]byte, 0, info.Size)
+	for uint64(len(body)) < info.Size {
+		msg, err := sub.NextMsgWithContext(ctx)
+		if err != nil {
+			return nil, err
+		}
+		body = append(body, msg.Data...)
+	}
+	return body, nil
+}
+
+// **The buckets' grants on a real server, judged by the node-engine's own call** (novox/hq ADR 0486 §2, issue 1697, 1697/AC2): the
+// controller's account writes an object into each node's bucket, a node-engine's account reads one of its own bucket by its name,
+// a large object included, and is refused a list of the bucket (a stream info asking for every subject), a message get by
+// sequence, a direct get by sequence, a consumer on the names, and a write; it is refused every one of those and the read by name on
+// another node's bucket, **the literal-`*` forms included** (a published subject `...M.*` or `...C.*` matches the grant's `*`: on
+// its own bucket that reaches its own files, on another's it is refused); another module's account is refused all of them.
+func TestNatsANodeEngineReadsAnObjectOfItsOwnBucketByNameAndNothingElse(t *testing.T) { // 1697/AC2
+	hash, err := bcrypt.GenerateFromPassword([]byte("pw"), bcrypt.MinCost)
+	if err != nil {
+		t.Fatal(err)
+	}
+	users, err := Users(Records{Nodes: []string{"alpha", "beta"}, Assigned: map[string][]Declared{
+		"alpha": {{Module: RuntimeModule}, {Module: "other-module"}},
+	}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	for i := range users {
+		users[i].PasswordHash = string(hash)
+	}
+	accounts, err := ComposeAccounts(users)
+	if err != nil {
+		t.Fatal(err)
+	}
+	conf := filepath.Join(t.TempDir(), "bus.conf")
+	if err := os.WriteFile(conf, []byte("listen: 127.0.0.1:-1\njetstream { store_dir: "+
+		`"`+t.TempDir()+`"`+" }\n"+accounts), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	opts, err := server.ProcessConfigFile(conf)
+	if err != nil {
+		t.Fatalf("the composed accounts do not parse: %v", err)
+	}
+	opts.NoLog, opts.NoSigs = true, true
+	s, err := server.NewServer(opts)
+	if err != nil {
+		t.Fatal(err)
+	}
+	go s.Start()
+	if !s.ReadyForConnections(10 * time.Second) {
+		t.Fatal("the bus did not come up")
+	}
+	t.Cleanup(s.Shutdown)
+
+	ctx, cancel := context.WithTimeout(context.Background(), 90*time.Second)
+	defer cancel()
+	connect := func(user string) (*nats.Conn, chan error) {
+		t.Helper()
+		refused := make(chan error, 16)
+		nc, err := nats.Connect(s.ClientURL(), nats.UserInfo(user, "pw"), nats.CustomInboxPrefix("_INBOX."+user),
+			nats.ErrorHandler(func(_ *nats.Conn, _ *nats.Subscription, err error) { refused <- err }))
+		if err != nil {
+			t.Fatalf("%s cannot connect: %v", user, err)
+		}
+		t.Cleanup(nc.Close)
+		return nc, refused
+	}
+
+	// The controller makes the buckets (as it does at its start) and writes into each: for alpha a small object and one of
+	// several chunks, which needs the consumer's flow control; for beta one that holds a marker alpha must never read.
+	controller, _ := connect(ControllerName)
+	cjs, err := jetstream.New(controller)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := EnsureDeclarationFiles(ctx, cjs, "alpha", "beta"); err != nil {
+		t.Fatalf("the controller cannot make the buckets: %v", err)
+	}
+	if err := EnsureDeclarationFiles(ctx, cjs, "alpha", "beta"); err != nil {
+		t.Fatalf("asserting them again: %v", err)
+	}
+	put := func(node string, content []byte) string {
+		t.Helper()
+		store, err := cjs.ObjectStore(ctx, mustBucket(t, node))
+		if err != nil {
+			t.Fatal(err)
+		}
+		sum := sha256.Sum256(content)
+		name := hex.EncodeToString(sum[:])
+		if _, err := store.PutBytes(ctx, name, content); err != nil {
+			t.Fatalf("the controller cannot write the object %s of %s: %v", name[:8], node, err)
+		}
+		return name
+	}
+	small := bytes.Repeat([]byte("small file\n"), 100)
+	large := make([]byte, 900<<10)
+	for i := range large {
+		large[i] = byte(i*7 + i>>8)
+	}
+	secret := bytes.Repeat([]byte("BETA-SECRET "), 50)
+	smallName, largeName, betaName := put("alpha", small), put("alpha", large), put("beta", secret)
+
+	alpha, alphaRefused := connect("node.alpha")
+	for name, want := range map[string][]byte{smallName: small, largeName: large} {
+		got, err := nodeEnginesFileObject(ctx, alpha, "alpha", name)
+		if err != nil {
+			t.Fatalf("a node-engine cannot read the object %s of its own bucket by its name: %v", name[:8], err)
+		}
+		if !bytes.Equal(got, want) {
+			t.Fatalf("the node-engine read %d bytes of the object %s, want %d", len(got), name[:8], len(want))
+		}
+	}
+	beta, _ := connect("node.beta")
+	if got, err := nodeEnginesFileObject(ctx, beta, "beta", betaName); err != nil || !bytes.Equal(got, secret) {
+		t.Fatalf("beta's node-engine reads its own object: %v", err)
+	}
+	select {
+	case err := <-alphaRefused:
+		t.Fatalf("a node-engine's own read was refused something: %v", err)
+	default:
+	}
+
+	// What each account is refused, judged by the server.
+	alphaStream, alphaBucket := mustStream(t, "alpha"), mustBucket(t, "alpha")
+	betaStream, betaBucket := mustStream(t, "beta"), mustBucket(t, "beta")
+	listing := []byte(`{"subjects_filter":">"}`)
+	bySeq := []byte(`{"seq":1}`)
+	type refusal struct {
+		what string
+		do   func(nc *nats.Conn)
+	}
+	onBucket := func(stream, bucket, which string) []refusal {
+		return []refusal{
+			{which + ": a list of the bucket (stream info asking for every subject)", func(nc *nats.Conn) {
+				_, _ = nc.Request("$JS.API.STREAM.INFO."+stream, listing, 300*time.Millisecond)
+			}},
+			{which + ": a message get by sequence", func(nc *nats.Conn) {
+				_, _ = nc.Request("$JS.API.STREAM.MSG.GET."+stream, bySeq, 300*time.Millisecond)
+			}},
+			{which + ": a direct get by sequence", func(nc *nats.Conn) {
+				_, _ = nc.Request("$JS.API.DIRECT.GET."+stream, bySeq, 300*time.Millisecond)
+			}},
+			{which + ": a consumer on every object's name", func(nc *nats.Conn) {
+				js, _ := nc.JetStream(nats.MaxWait(500 * time.Millisecond))
+				if sub, err := js.SubscribeSync("$O."+bucket+".M.>", nats.OrderedConsumer(), nats.BindStream(stream)); err == nil {
+					sub.Unsubscribe()
+				}
+			}},
+			{which + ": a write of an object's metadata", func(nc *nats.Conn) {
+				_ = nc.Publish("$O."+bucket+".M.abc", []byte(`{}`))
+				_ = nc.Flush()
+			}},
+			{which + ": a write of a chunk", func(nc *nats.Conn) {
+				_ = nc.Publish("$O."+bucket+".C.abc", []byte("x"))
+				_ = nc.Flush()
+			}},
+		}
+	}
+	refusedWith := func(who string, nc *nats.Conn, ch chan error, r refusal) {
+		t.Helper()
+		for len(ch) > 0 {
+			<-ch
+		}
+		r.do(nc)
+		_ = nc.Flush()
+		deadline := time.After(3 * time.Second)
+		for {
+			select {
+			case err := <-ch:
+				if errors.Is(err, nats.ErrPermissionViolation) {
+					return
+				}
+			case <-deadline:
+				t.Errorf("the server did not refuse %s %s", who, r.what)
+				return
+			}
+		}
+	}
+	// Alpha's account on its own bucket (list, sequence reads, names, writes) and on beta's (all of that, and the read by name,
+	// and the literal-`*` probes of the review).
+	reachBeta := []refusal{
+		{"beta's bucket: a read of one object by its name", func(nc *nats.Conn) {
+			_, _ = nc.Request("$JS.API.DIRECT.GET."+betaStream+".$O."+betaBucket+".M."+
+				base64.URLEncoding.EncodeToString([]byte(betaName)), nil, 300*time.Millisecond)
+		}},
+		{"beta's bucket: a direct get with a literal `*` for the name", func(nc *nats.Conn) {
+			_, _ = nc.Request("$JS.API.DIRECT.GET."+betaStream+".$O."+betaBucket+".M.*", nil, 300*time.Millisecond)
+		}},
+		{"beta's bucket: a consumer with a literal `*` for the chunks", func(nc *nats.Conn) {
+			js, _ := nc.JetStream(nats.MaxWait(500 * time.Millisecond))
+			if sub, err := js.SubscribeSync("$O."+betaBucket+".C.*", nats.OrderedConsumer(), nats.BindStream(betaStream)); err == nil {
+				sub.Unsubscribe()
+			}
+		}},
+	}
+	all := append(append(onBucket(alphaStream, alphaBucket, "its own bucket"), onBucket(betaStream, betaBucket, "beta's bucket")...), reachBeta...)
+	for _, r := range all {
+		nodeNC, nodeCh := connect("node.alpha")
+		refusedWith("a node-engine", nodeNC, nodeCh, r)
+	}
+	// Another module is refused all of that on both buckets, and the reads by name on both.
+	for _, r := range append(append(onBucket(alphaStream, alphaBucket, "alpha's bucket"), reachBeta...),
+		refusal{"alpha's bucket: a read of one object by its name", func(nc *nats.Conn) {
+			_, _ = nc.Request("$JS.API.DIRECT.GET."+alphaStream+".$O."+alphaBucket+".M."+
+				base64.URLEncoding.EncodeToString([]byte(smallName)), nil, 300*time.Millisecond)
+		}}) {
+		otherNC, otherCh := connect("alpha.other-module")
+		refusedWith("another module", otherNC, otherCh, r)
+	}
+
+	// The literal `*` on alpha's own bucket reaches alpha's own files and never beta's: the chunks it is given hold no marker of beta's.
+	js, err := alpha.JetStream(nats.MaxWait(2 * time.Second))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if sub, err := js.SubscribeSync("$O."+alphaBucket+".C.*", nats.OrderedConsumer(), nats.BindStream(alphaStream)); err == nil {
+		for i := 0; i < 20; i++ {
+			msg, err := sub.NextMsg(300 * time.Millisecond)
+			if err != nil {
+				break
+			}
+			if bytes.Contains(msg.Data, []byte("BETA-SECRET")) {
+				t.Fatal("a literal `*` on alpha's bucket gave it a chunk of beta's file")
+			}
+		}
+		sub.Unsubscribe()
+	}
+
+	// Nothing was written by the refused: each bucket holds what the controller wrote.
+	for node, want := range map[string]int{"alpha": 2, "beta": 1} {
+		store, err := cjs.ObjectStore(ctx, mustBucket(t, node))
+		if err != nil {
+			t.Fatal(err)
+		}
+		infos, err := store.List(ctx)
+		if err != nil || len(infos) != want {
+			t.Errorf("the bucket of %s holds %d objects (%v), want the %d the controller wrote", node, len(infos), err, want)
+		}
+	}
+}
+
+func mustBucket(t *testing.T, node string) string {
+	t.Helper()
+	b, err := DeclarationFilesBucketOf(node)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return b
+}
+
+func mustStream(t *testing.T, node string) string {
+	t.Helper()
+	b, err := DeclarationFilesStreamOf(node)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return b
+}

internal/broker/declaration_files_test.go

@@ -0,0 +1,131 @@
+package broker
+
+import (
+	"slices"
+	"strings"
+	"testing"
+)
+
+// 1697/AC1: the composed accounts give a node-engine exactly the four reads of one object by its name, on its own node's bucket and
+// no other's; the controller the write of every node's bucket; and no other principal anything of any bucket.
+func TestEachNodesBucketIsWrittenByTheControllerAndReadByNameByThatNodesEngine(t *testing.T) { // 1697/AC1
+	node, err := PermissionsFor(Principal{Kind: KindNode, Node: "alpha", PasswordHash: "x"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	var mine []string
+	for _, s := range node.Publish {
+		if strings.Contains(s, "declaration-files") {
+			mine = append(mine, s)
+		}
+	}
+	want := []string{
+		"$JS.API.CONSUMER.CREATE.OBJ_declaration-files-alpha.*.$O.declaration-files-alpha.C.*",
+		"$JS.API.CONSUMER.DELETE.OBJ_declaration-files-alpha.*",
+		"$JS.API.DIRECT.GET.OBJ_declaration-files-alpha.$O.declaration-files-alpha.M.*",
+		"$JS.FC.OBJ_declaration-files-alpha.>",
+	}
+	if !slices.Equal(mine, want) {
+		t.Fatalf("a node-engine may publish %q of the buckets, want exactly %q", mine, want)
+	}
+	// What would make a list, a write, or a read of another node's files: none of it, in any pattern a node holds. (The real
+	// server's judgement of the wildcard forms is the live test's.)
+	for _, refused := range []string{
+		"$JS.API.STREAM.INFO.OBJ_declaration-files-alpha",
+		"$JS.API.STREAM.MSG.GET.OBJ_declaration-files-alpha",
+		"$JS.API.DIRECT.GET.OBJ_declaration-files-alpha",
+		"$JS.API.DIRECT.GET.OBJ_declaration-files-alpha.$O.declaration-files-alpha.M.abc.def",
+		"$JS.API.CONSUMER.CREATE.OBJ_declaration-files-alpha.x.$O.declaration-files-alpha.M.YWJj",
+		"$JS.API.CONSUMER.CREATE.OBJ_declaration-files-alpha.x.$O.declaration-files-alpha.M.YWJj.more",
+		"$JS.API.CONSUMER.CREATE.OBJ_declaration-files-alpha",
+		"$O.declaration-files-alpha.M.abc",
+		"$O.declaration-files-alpha.C.abc",
+		// another node's bucket, however it is named
+		"$JS.API.DIRECT.GET.OBJ_declaration-files-beta.$O.declaration-files-beta.M.YWJj",
+		"$JS.API.CONSUMER.CREATE.OBJ_declaration-files-beta.h4sh.$O.declaration-files-beta.C.NUID",
+		"$JS.API.CONSUMER.DELETE.OBJ_declaration-files-beta.h4sh",
+		"$JS.FC.OBJ_declaration-files-beta.x",
+		// and the old shared bucket
+		"$JS.API.DIRECT.GET.OBJ_declaration-files.$O.declaration-files.M.YWJj",
+	} {
+		if MayPublish(node, refused) {
+			t.Errorf("a node-engine may publish %s, which lists or writes a bucket or reads another node's", refused)
+		}
+	}
+	for _, kept := range []string{
+		"$JS.API.DIRECT.GET.OBJ_declaration-files-alpha.$O.declaration-files-alpha.M.YWJj",
+		"$JS.API.CONSUMER.CREATE.OBJ_declaration-files-alpha.h4sh.$O.declaration-files-alpha.C.NUID",
+	} {
+		if !MayPublish(node, kept) {
+			t.Errorf("a node-engine may not publish %s, which reads one object of its own bucket by its name", kept)
+		}
+	}
+
+	controller, err := PermissionsFor(Principal{Kind: KindController, PasswordHash: "x", FilesFor: []string{"alpha", "beta"}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, s := range []string{"$O.declaration-files-alpha.M.abc", "$O.declaration-files-beta.C.nuid"} {
+		if !MayPublish(controller, s) {
+			t.Errorf("the controller may not write %s", s)
+		}
+	}
+	if MayPublish(controller, "$O.declaration-files-gamma.M.abc") {
+		t.Error("the controller may write the bucket of a node it was not given")
+	}
+
+	for _, p := range []Principal{
+		{Kind: KindModule, Module: "mesh-vault", PasswordHash: "x"},
+		{Kind: KindNodeTools, Node: "alpha", PasswordHash: "x"},
+		{Kind: KindPerson, Module: "jochen", Invokes: []string{"*"}, PasswordHash: "x"},
+	} {
+		perms, err := PermissionsFor(p)
+		if err != nil {
+			t.Fatal(err)
+		}
+		for _, s := range append(append([]string(nil), perms.Publish...), perms.Subscribe...) {
+			if strings.Contains(s, "declaration-files") {
+				t.Errorf("%s holds %s, and no account but the controller's and the node-engines' has any access", p.Username(), s)
+			}
+		}
+	}
+}
+
+// The users the controller composes carry each node's bucket to the controller and to that node alone.
+func TestTheComposedUsersGiveEachNodeItsOwnBucketAndTheControllerAll(t *testing.T) {
+	users, err := Users(Records{Nodes: []string{"alpha", "beta"}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	var controller Principal
+	for _, u := range users {
+		if u.Kind == KindController {
+			controller = u
+		}
+	}
+	if !slices.Equal(controller.FilesFor, []string{"alpha", "beta"}) {
+		t.Fatalf("the controller writes the buckets of %v", controller.FilesFor)
+	}
+}
+
+// A node name that could carry a subject wildcard or separator into a grant is refused with an error, never composed into a bucket
+// (ADR 0488): the grants of such a name would reach another node's bucket.
+func TestANodeNameThatCarriesAWildcardGetsNoBucketAndNoGrant(t *testing.T) {
+	for _, node := range []string{"", "*", ">", "a.b", "a b", "a*"} {
+		if b, err := DeclarationFilesBucketOf(node); err == nil {
+			t.Errorf("node %q got the bucket %q", node, b)
+		}
+		if _, err := DeclarationFilesReads(node); err == nil {
+			t.Errorf("node %q got read grants", node)
+		}
+		if _, err := DeclarationFilesWrites(node); err == nil {
+			t.Errorf("node %q got write grants", node)
+		}
+		if _, err := DeclarationFilesConfig(node); err == nil {
+			t.Errorf("node %q got a bucket config", node)
+		}
+	}
+	if b, err := DeclarationFilesBucketOf("g14"); err != nil || b != "declaration-files-g14" {
+		t.Errorf("g14: %q %v", b, err)
+	}
+}

internal/broker/nats.go

@@ -104,6 +104,10 @@ type Principal struct {
 	// Username and inbox are <node>.<module>.<process id>.
 	Process string
 
+	// FilesFor are the nodes whose declaration-file buckets this principal writes, for the controller alone (novox/hq ADR 0486 §2):
+	// every node of the mesh, one bucket each.
+	FilesFor []string
+
 	Emits    []string
 	Consumes []string
 	Serves   []string
@@ -736,6 +740,15 @@ func PermissionsFor(p Principal) (Permissions, error) {
 			}
 			pub = append(pub, "$KV."+bucket+".>")
 		}
+		// **And the object bucket a declaration's large files travel in** (novox/hq ADR 0486 §2, issue 1697): the
+		// controller alone writes it, as a publish to the bucket's own subjects, which `$JS.API.>` does not cover.
+		for _, node := range p.FilesFor {
+			writes, err := DeclarationFilesWrites(node)
+			if err != nil {
+				return Permissions{}, err
+			}
+			pub = append(pub, writes)
+		}
 		// **And what the bus says about itself, read-only** (novox/hq to-be 45 §3, S9): a durable
 		// consumer that gave up on a message, or one that was deleted. The server already publishes
 		// both in the mesh's own account; the controller says each as a condition in the mesh's words.
@@ -835,6 +848,13 @@ func PermissionsFor(p Principal) (Permissions, error) {
 			return Permissions{}, err
 		}
 		pub = append(pub, haveKeys...)
+		// And an object of the declaration bucket by its name, and nothing of the bucket's list or writing
+		// (novox/hq ADR 0486 §2, issue 1697).
+		fileReads, err := DeclarationFilesReads(p.Node)
+		if err != nil {
+			return Permissions{}, err
+		}
+		pub = append(pub, fileReads...)
 		// And, while the vault serves it, the vault's move-in in its own name and nobody else's (issue 676): the
 		// values sealed to this machine, which only it opens, handed in sealed to the vault's key for the call.
 		if p.MovesIntoTheVault {

internal/broker/testdata/composed.conf

@@ -38,7 +38,7 @@ accounts {
         subscribe: { allow: ["_INBOX.enrol.one.>"] }
       } }
       { user: "node.one", password: "$2a$11$nnnnnnnnnnnnnnnnnnnnnn", permissions: {
-        publish: { allow: ["$JS.ACK.NODES.one.>", "$JS.API.CONSUMER.CREATE.KV_node-engine_have.*.$KV.node-engine_have.one.>", "$JS.API.CONSUMER.DELETE.KV_node-engine_have.>", "$JS.API.CONSUMER.INFO.NODES.one", "$JS.API.DIRECT.GET.KV_node-engine_have.$KV.node-engine_have.one.>", "$JS.API.STREAM.INFO.KV_node-engine_have", "$JS.FC.KV_node-engine_have.>", "$KV.node-engine_have.one.>", "$SRV.PING.node-tools.one", "mesh.control.one.>"] }
+        publish: { allow: ["$JS.ACK.NODES.one.>", "$JS.API.CONSUMER.CREATE.KV_node-engine_have.*.$KV.node-engine_have.one.>", "$JS.API.CONSUMER.CREATE.OBJ_declaration-files-one.*.$O.declaration-files-one.C.*", "$JS.API.CONSUMER.DELETE.KV_node-engine_have.>", "$JS.API.CONSUMER.DELETE.OBJ_declaration-files-one.*", "$JS.API.CONSUMER.INFO.NODES.one", "$JS.API.DIRECT.GET.KV_node-engine_have.$KV.node-engine_have.one.>", "$JS.API.DIRECT.GET.OBJ_declaration-files-one.$O.declaration-files-one.M.*", "$JS.API.STREAM.INFO.KV_node-engine_have", "$JS.FC.KV_node-engine_have.>", "$JS.FC.OBJ_declaration-files-one.>", "$KV.node-engine_have.one.>", "$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.judge-directories", "mesh.node.one.ask.move-secret", "mesh.node.one.ask.report", "mesh.node.one.ask.setuid-search", "mesh.node.one.declare"] }
         allow_responses: { max: 1, ttl: "1m" }
       } }

internal/broker/users.go

@@ -135,7 +135,7 @@ type Records struct {
 // correct.
 func Users(r Records) ([]Principal, error) {
 	out := []Principal{{Kind: KindController, Uses: asksSeatOf(r), AsksIssued: issuedOf(r), AsksTheVault: vaultVerbsOf(r),
-		AsksTheConfig: servedOf(r, VerbsTheControllerAsksTheConfig)}}
+		AsksTheConfig: servedOf(r, VerbsTheControllerAsksTheConfig), FilesFor: sortedCopy(r.Nodes)}}
 
 	for _, node := range sortedCopy(r.Nodes) {
 		witness := false

internal/broker/writers.go

@@ -219,6 +219,13 @@ var WritersTable = []WriterRow{
 	{State: "a machine's have", Writer: "the node-engine of the machine, under its own keys `<node>.>`",
 		KeptIn: "key-value " + delivery.HaveBucket + ", twenty revisions of each key",
 		Others: "read through `reads` as node-engine.have", Subjects: kvOf(delivery.HaveBucket), Writes: ownNodeKeys},
+	// The contents of a declaration's files over 64 KiB (novox/hq ADR 0486 §2): the controller alone writes the bucket, each
+	// object under the digest of its content; a node-engine reads one by its name, with no list and no write.
+	{State: "a declaration's large files", Writer: "controller, each object under the sha256 digest of its content",
+		KeptIn: "the object bucket " + DeclarationFilesBucket + "-<node> of each node, an object removed a day after the " +
+			"node's latest declaration no longer names it",
+		Others:   "a node-engine reads an object of its own bucket by its name and may neither list the bucket nor write it",
+		Subjects: []string{"$O.*.>"}, Writes: isController},
 	{State: "the declared-config mirror", Writer: "controller (lease holder), from its store, only on a change",
 		KeptIn: "key-value " + DeclaredConfigBucket, Others: "read through `reads` as mesh-controller." + MirrorDeclaredConfig,
 		Subjects: kvOf(DeclaredConfigBucket), Writes: isController},

internal/broker/writers_test.go

@@ -43,6 +43,8 @@ var designRows = []string{
 	"the rollouts of the chain",
 	// What each machine has of each module, written by its node-engine under its own keys (ADR 0429 §1, issue 1136).
 	"a machine's have",
+	// The contents of a declaration's large files, in the bus's object bucket (ADR 0486 §2, issue 1697).
+	"a declaration's large files",
 	"the declared-config mirror",
 	"the predefined-keys mirror",
 	// The provisioner client's word on what it placed (novox/hq ADR 0349 §4, design 57 P6).

internal/link/builds_nats.go

@@ -362,14 +362,6 @@ func (m *natsMachine) Take(ctx context.Context, do func(context.Context, Build))
 			_ = msg.Nak()
 			continue
 		}
-		// **A duplicate of a check another builder is running is dropped** (issue 1649): an ask redelivered to this machine
-		// because its first holder did not say, in time, that it had it. The running key names that builder and this same
-		// ask; running it a second time would spend a second place on one check.
-		if why := m.runningElsewhere(ctx, request); why != "" {
-			fmt.Fprintf(os.Stderr, "%s is handed out again while another builder runs it and is dropped: %s\n", request.ID, why)
-			_ = msg.Ack()
-			continue
-		}
 		// A build outlives the acknowledgement window many times over; said while it runs,
 		// as the controller says it for its own long handlers, so the server neither hands
 		// the ask to a second machine nor counts the wait against its deliveries.
@@ -384,35 +376,6 @@ func (m *natsMachine) Take(ctx context.Context, do func(context.Context, Build))
 	}
 }
 
-// runningElsewhere says why an ask need not run here, or nothing: the bucket of the checks running says another builder
-// runs this very ask (its id, its head and its trunk commit). A key that cannot be read runs the check.
-func (m *natsMachine) runningElsewhere(ctx context.Context, r BuildRequest) string {
-	if r.Check == nil {
-		return ""
-	}
-	running, ok, err := ReadRunning(ctx, m.js.Conn(), r)
-	if err != nil {
-		fmt.Fprintf(os.Stderr, "could not read whether %s is running elsewhere, so it runs: %v\n", r.ID, err)
-		return ""
-	}
-	return duplicateOf(running, ok, r, m.on)
-}
-
-// runningFreshFor is how recent a running key's last heartbeat must be for its builder to be taken as alive: two missed
-// heartbeats of ten seconds are not yet a dead builder, and a redelivery after a crash comes a minute after the last one.
-const runningFreshFor = 25 * time.Second
-
-// duplicateOf says why an ask is a second hand-out of one another builder is running, or nothing.
-func duplicateOf(running CheckRunning, found bool, r BuildRequest, me string) string {
-	// Seen is the server's time and runningFreshFor is judged against this builder's clock: a skew over about 35 s would matter.
-	// A key not renewed for runningFreshFor is a builder that has gone: its ask is redelivered after the ack wait, and
-	// that is the recovery, not a duplicate (the key itself lives two minutes).
-	if found && running.Build == r.ID && running.Builder != me && running.Same(r) && time.Since(running.Seen) < runningFreshFor {
-		return fmt.Sprintf("%s is running it as %s since %s", running.Builder, running.Build, running.Started.Local().Format("15:04:05"))
-	}
-	return ""
-}
-
 // bind binds a queue's worker, which exists and is not created here.
 //
 // **The consumer's own filter, not the one subject this machine cares about.** The client checks what is asked for

internal/link/bus_nats.go

@@ -24,3 +24,6 @@ func ConnectNats(js *broker.JetStream, enroller Enroller, listener Listener) *Se
 // Bus is the controller's outbound, whichever transport it connected over. Callers that send a
 // declaration or ask a tool use this rather than the channel, which one transport does not have.
 func (s *Server) Bus() Bus { return s.bus }
+
+// SendingOn is a server that only sends, over the bus given: for a test of a sender with a bus it holds in its hand.
+func SendingOn(bus Bus) *Server { return &Server{bus: bus} }

internal/link/checks_nats.go

@@ -253,25 +253,11 @@ func watchPullIn(ctx context.Context, buckets []string, open func(ctx context.Co
 
 // checkTakeWait is how long a taking loop waits on one queue for an ask that is not there, and takeIdleWait how long it
 // waits on the first when all three are empty.
-//
-// **A fetch's pull request must end before the fetch does** (issue 1649). nats.go gives the server-side request an expiry a tenth
-// shorter than the fetch's wait (fetchExpiryOf), and the server then answers with a status message at the expiry; a wait so
-// short that the answer can land after the fetch gave up left a status message in the pull's buffer, and anything a request
-// could still deliver would be held by a machine that is busy. Each wait leaves at least minFetchMargin between the two.
 const (
-	checkTakeWait = 100 * time.Millisecond
+	checkTakeWait = 30 * time.Millisecond
 	takeIdleWait  = time.Second
 )
 
-// minFetchMargin is the least time between a fetch's server-side expiry and the end of its wait.
-const minFetchMargin = 10 * time.Millisecond
-
-// fetchExpiryOf is the expiry nats.go gives the pull request of a fetch that waits this long: the wait less a tenth of it, or
-// less five seconds.
-func fetchExpiryOf(wait time.Duration) time.Duration {
-	return wait - min(wait/10, 5*time.Second)
-}
-
 // CheckRunning is what a builder says of the check it is running, in the bucket of the checks running (novox/hq ADR 0406
 // §3): the head and trunk commit it checks, the builder and its build. The key is the pull request's (RunningKeyOf).
 type CheckRunning struct {
@@ -282,8 +268,6 @@ type CheckRunning struct {
 	// Started is when the check started, kept on every heartbeat: the entry's own time is the last heartbeat's, and a
 	// reader that asks how long a check has run reads this (novox/hq ADR 0433 §6).
 	Started time.Time `json:"started"`
-	// Seen is when the key was last put, which is the last heartbeat: read from the entry, never written (issue 1649).
-	Seen time.Time `json:"-"`
 }
 
 // RunningKeyOf is the key a check is said running under: its pull request's tokens, or `group.<name>` for a group's
@@ -335,7 +319,6 @@ func ReadRunning(ctx context.Context, conn *nats.Conn, r BuildRequest) (CheckRun
 	if err := json.Unmarshal(e.Value(), &running); err != nil {
 		return CheckRunning{}, false, nil // a key of a builder from before this means no match
 	}
-	running.Seen = e.Created()
 	return running, true, nil
 }
 

internal/link/checks_nats_integration_test.go

@@ -6,7 +6,6 @@ import (
 	"context"
 	"encoding/json"
 	"reflect"
-	"strings"
 	"testing"
 	"time"
 
@@ -511,122 +510,3 @@ func TestAnUnacknowledgedCheckGoesToASecondBuilder(t *testing.T) {
 		stop()
 	}
 }
-
-// An ask handed out a second time to another builder while the first still runs it is acknowledged and not run: the
-// running key names the other builder and this same ask (issue 1649).
-func TestAnAskHandedOutAgainWhileAnotherBuilderRunsItIsNotRunTwice(t *testing.T) {
-	js := aBusWithTheBuildRole(t)
-	aKeyBucket(t, js)
-	aRunningBucket(t, js, 2*time.Minute)
-	ctx, stop := context.WithCancel(t.Context())
-	defer stop()
-	asks := BuildsOn(js, TheBuildMachine)
-	running := make(chan string, 4)
-	release := make(chan struct{})
-	a := MachineOverNATS(js, "builder-a")
-	defer a.Close()
-	go func() {
-		_ = a.Take(ctx, func(ctx context.Context, work Build) {
-			running <- work.Request().ID
-			<-release
-			_ = work.Announce(ctx, BuildResult{ID: work.Request().ID, On: "builder-a", Failed: "no"})
-			_ = work.Done()
-		})
-	}()
-	check := aPullCheck("build-twice", 7, "head-7-000000000", "trunk-1-000000", false)
-	if err := asks.Ask(ctx, check); err != nil {
-		t.Fatal(err)
-	}
-	select {
-	case <-running:
-	case <-time.After(10 * time.Second):
-		t.Fatal("builder a took nothing")
-	}
-	// The bus's redelivery, as it reaches the other machine: the same ask, the same id.
-	if err := asks.Ask(ctx, check); err != nil {
-		t.Fatal(err)
-	}
-	b := MachineOverNATS(js, "builder-b")
-	defer b.Close()
-	took := make(chan string, 4)
-	go func() {
-		_ = b.Take(ctx, func(ctx context.Context, work Build) {
-			took <- work.Request().ID
-			_ = work.Done()
-		})
-	}()
-	select {
-	case id := <-took:
-		t.Fatalf("builder b ran %s, which builder a is running", id)
-	case <-time.After(3 * time.Second):
-	}
-	if n := len(queueOf(t, js).Of(AskWaiting)); n != 0 {
-		t.Errorf("%d request(s) still wait; builder b was to acknowledge the duplicate", n)
-	}
-	close(release)
-}
-
-// A busy machine fetches nothing, so no ask waiting in the queue is taken by it, whatever status message sits in its pulls
-// (issue 1649). A pull request of our own that expires at once leaves such a message in the other checks' pull.
-func TestABusyMachineTakesNoWaitingAskWhateverItsPullsHold(t *testing.T) {
-	js := aBusWithTheBuildRole(t)
-	aKeyBucket(t, js)
-	aRunningBucket(t, js, 2*time.Minute)
-	ctx, stop := context.WithCancel(t.Context())
-	defer stop()
-	asks := BuildsOn(js, TheBuildMachine)
-	busy := make(chan string, 4)
-	release := make(chan struct{})
-	a := MachineOverNATS(js, "builder-a").(*natsMachine)
-	defer a.Close()
-	go func() {
-		_ = a.Take(ctx, func(ctx context.Context, work Build) {
-			busy <- work.Request().ID
-			<-release
-			_ = work.Announce(ctx, BuildResult{ID: work.Request().ID, On: "builder-a", Failed: "no"})
-			_ = work.Done()
-		})
-	}()
-	if err := asks.Ask(ctx, BuildRequest{ID: "busy", Repository: "/d"}); err != nil {
-		t.Fatal(err)
-	}
-	select {
-	case <-busy:
-	case <-time.After(10 * time.Second):
-		t.Fatal("builder a took nothing")
-	}
-	var other *takeQueue
-	for _, q := range a.subs {
-		if q.kind == queueOther && q.bound {
-			other = q
-		}
-	}
-	if other == nil {
-		t.Fatal("builder a has no pull on the other checks")
-	}
-	// The queue is empty, so this request is answered at its expiry with a status message that lands in the pull.
-	reply := strings.TrimSuffix(other.sub.Subject, "*") + "late"
-	if err := js.Conn().PublishRequest("$JS.API.CONSUMER.MSG.NEXT."+other.worker.Stream+"."+other.worker.Name, reply,
-		[]byte(`{"batch":1,"expires":1000000}`)); err != nil {
-		t.Fatal(err)
-	}
-	time.Sleep(500 * time.Millisecond)
-	for i, id := range []string{"wait-1", "wait-2"} {
-		if err := asks.Ask(ctx, aPullCheck(id, 20+i, "head-x-000000000", "trunk-1-000000", false)); err != nil {
-			t.Fatal(err)
-		}
-	}
-	time.Sleep(5 * time.Second)
-	info, err := js.Context().ConsumerInfo(other.worker.Stream, other.worker.Name)
-	if err != nil {
-		t.Fatal(err)
-	}
-	if info.NumAckPending != 0 || info.NumRedelivered != 0 || info.Delivered.Consumer != 0 {
-		t.Fatalf("a busy machine took from the queue: %d delivered, %d pending, %d redelivered", info.Delivered.Consumer,
-			info.NumAckPending, info.NumRedelivered)
-	}
-	if n := len(queueOf(t, js).Of(AskWaiting)); n != 2 {
-		t.Fatalf("%d asks wait; want the 2 nobody took", n)
-	}
-	close(release)
-}

internal/link/declare.go

@@ -41,7 +41,7 @@ func Declare(ctx context.Context, bus Bus, signer Signer, node string,
 		return fmt.Errorf("cannot sign a declaration for %s: %w", node, err)
 	}
 
-	body, err := json.Marshal(Signed{Declaration: declaration, Signature: signature})
+	body, err := Envelope(declaration, signature)
 	if err != nil {
 		return err
 	}
@@ -66,8 +66,16 @@ func Declare(ctx context.Context, bus Bus, signer Signer, node string,
 	return bus.PublishDeclaration(publish, node, body)
 }
 
-// NearTheLimit is the share of the bus's largest message at which a declaration is said to be near it.
-const NearTheLimit = 0.9
+// Envelope is the message a declaration goes on the bus as: the declaration and its signature, each as base64 in one JSON
+// document. Its length is what the bus's largest message bounds.
+func Envelope(declaration, signature []byte) ([]byte, error) {
+	return json.Marshal(Signed{Declaration: declaration, Signature: signature})
+}
+
+// NearTheLimit is the share of the bus's largest message at which a declaration is said to be near it: three quarters, so that
+// a declaration which should stay far from the limit raises the condition while there is still room to act (novox/hq ADR 0486
+// §8; the first fix of issue 1689 warned at nine tenths while every file was still inline).
+const NearTheLimit = 0.75
 
 // DeclarationMeasured is told, at every send of a declaration, its size on the wire and the bus's largest message,
 // so the controller raises a condition when it nears the limit and clears it when it is back under (issue 1689).

internal/link/held_asks_test.go

@@ -1,43 +0,0 @@
-package link
-
-import (
-	"testing"
-	"time"
-)
-
-// An ask a machine holds but does not start gets no heartbeat, and the bus hands it to another machine after the ack
-// wait, so two machines run one check (issue 1649).
-
-// A fetch's server-side pull request ends clearly before the fetch does, so the server's answer and any message it could still
-// deliver come inside the fetch and never into a buffer nobody reads while the machine builds.
-func TestAFetchsPullRequestEndsClearlyBeforeTheFetchDoes(t *testing.T) {
-	for name, wait := range map[string]time.Duration{"a check queue": checkTakeWait, "the idle wait": takeIdleWait} {
-		if margin := wait - fetchExpiryOf(wait); margin < minFetchMargin {
-			t.Errorf("%s: the pull request ends %v before a fetch of %v does; want at least %v", name, margin, wait, minFetchMargin)
-		}
-	}
-}
-
-func TestAnAskAnotherBuilderIsRunningIsADuplicateAndYoursIsNot(t *testing.T) {
-	r := aPullCheck("build-1", 423, "head-4771ee53aa", "trunk-0123456789", false)
-	run := CheckRunning{Head: r.Ref, Trunk: "trunk-0123456789", Builder: "shanks", Build: "build-1", Started: time.Now().Add(-time.Minute), Seen: time.Now().Add(-4 * time.Second)}
-	dead := run
-	dead.Seen = time.Now().Add(-60 * time.Second)
-	for name, c := range map[string]struct {
-		running CheckRunning
-		found   bool
-		me      string
-		dup     bool
-	}{
-		"another builder runs this very ask":                {run, true, "ace", true},
-		"its builder stopped renewing the key a minute ago": {dead, true, "ace", false},
-		"this builder runs it itself":                       {run, true, "shanks", false},
-		"nobody runs it":                                    {CheckRunning{}, false, "ace", false},
-		"another ask of the same head":                      {CheckRunning{Head: r.Ref, Trunk: "trunk-0123456789", Builder: "shanks", Build: "build-0"}, true, "ace", false},
-		"the same ask at another head":                      {CheckRunning{Head: "head-other-0000", Trunk: "trunk-0123456789", Builder: "shanks", Build: "build-1"}, true, "ace", false},
-	} {
-		if got := duplicateOf(c.running, c.found, r, c.me) != ""; got != c.dup {
-			t.Errorf("%s: duplicate = %v; want %v", name, got, c.dup)
-		}
-	}
-}

testdata/beside/CAPTURED

@@ -9,7 +9,7 @@ a second place to clean besides the catalogue itself.
 
 mesh-catalog  e0bc919d4945bb5f13f971f74643a0b714cf45da  modules/*/module.json, modules/nats/Dockerfile
 mesh-host     9d9e3a46c4f5943cfffb413d962ce48b75e2fd39  examples/foundation-first-node.lock
-mesh-sdk      465beb4ea5e37eb36f6ba7fc60274de2d5a0d060  conformance/events/module-event.json
+mesh-sdk      86f9a1a5c5088b60f694324e84dc31f682156a1b  conformance/events/module-event.json
 
 To move them, from this repository's root, with the two repositories checked out beside it:
 

vendor/git.novox.be/novox/mesh-sdk/go/catalogue/manifest.go

@@ -2214,6 +2214,7 @@ func parseManifest(raw []byte, predefined PredefinedList) (Manifest, error) {
 	problems = append(problems, replacesProblems(m)...)
 	problems = append(problems, UnitSettingProblems(m)...)
 	problems = append(problems, OwnerSettingProblems(m)...)
+	problems = append(problems, GroupSettingProblems(m)...)
 	problems = append(problems, endpointNameProblems(m)...)
 	problems = append(problems, RouteProblems(m)...)
 	for _, port := range m.Guards {

vendor/git.novox.be/novox/mesh-sdk/go/catalogue/resolve.go

@@ -904,7 +904,7 @@ func isModule(catalogue map[string]Manifest, want string) bool {
 // machine can host the module as far as its capabilities go.
 func missingCapabilities(m Manifest, node Node) []string {
 	var missing []string
-	for _, c := range m.Capabilities {
+	for _, c := range append(append([]string(nil), m.Capabilities...), impliedCapabilities(m)...) {
 		if !node.Capabilities[c] {
 			missing = append(missing, c)
 		}
@@ -1457,3 +1457,20 @@ func packageNames(m map[string][]string) []string {
 	sort.Strings(names)
 	return names
 }
+
+// ContainerGroups is the capability a node-engine reports when it reads a container's `groups` and passes each as a
+// supplementary group (novox/hq ADR 0480 clause 7, issue 1638). An older engine refuses the key (strict decoding).
+const ContainerGroups = "container-groups"
+
+// impliedCapabilities are the capabilities a module needs for what its resources say, beyond those it declares: a
+// container that names groups needs an engine that reads them, so the module is left out of a machine whose report
+// lacks the capability, naming it, and the field is sent to no engine that would refuse it. None for a module whose
+// containers name no groups.
+func impliedCapabilities(m Manifest) []string {
+	for _, r := range m.Resources {
+		if fmt.Sprint(r["type"]) == "container" && len(groupsOf(r)) > 0 {
+			return []string{ContainerGroups}
+		}
+	}
+	return nil
+}

vendor/git.novox.be/novox/mesh-sdk/go/catalogue/seat_data.go

@@ -66,7 +66,8 @@ var capabilityName = regexp.MustCompile(`^[a-z0-9][a-z0-9-]*$`)
 // names an `if-capability` may give (novox/hq ADR 0255). A name nothing detects would leave its
 // contribution out on every machine, silently, so it is refused. A detector added there is added here.
 var KnownCapabilities = []string{
-	"battery", "container-runtime", "firewall", "graphical-session", "overlay", "package-manager",
+	"battery", "container-groups", "container-runtime", "file-references", "firewall", "graphical-session", "overlay",
+	"package-manager",
 	"power-meter", "privileged", "seat", "service-manager", "uplink-dhcpcd", "uplink-networkmanager",
 	"uplink-systemd-networkd", "user-namespaces", "virtualisation",
 }

vendor/git.novox.be/novox/mesh-sdk/go/catalogue/setting_into.go

@@ -85,6 +85,9 @@ func settingInto(resource map[string]any, layers []Layer, module string) error {
 	if fmt.Sprint(resource["type"]) == "directory" {
 		return settingIntoOwner(resource, layers, module)
 	}
+	if fmt.Sprint(resource["type"]) == "container" {
+		return settingIntoGroups(resource, layers, module)
+	}
 	if fmt.Sprint(resource["type"]) != "file" {
 		return nil
 	}
@@ -343,6 +346,12 @@ func settingKeysAskedOutsideOwners(m Manifest) map[string]bool {
 			if unit, ok := r["unit"].(string); ok {
 				note(unit)
 			}
+		case "container":
+			for _, g := range groupsOf(r) {
+				if s, ok := g.(string); ok {
+					note(s)
+				}
+			}
 		}
 	}
 	inValues := func(values map[string]any) {
@@ -365,3 +374,100 @@ func settingKeysAskedOutsideOwners(m Manifest) map[string]bool {
 	}
 	return used
 }
+
+// A container's supplementary groups may be an operator's value (novox/hq ADR 0480 clause 7, ADR 0348 §11, issue 1636):
+// n8n joins the media library's group, whose number is the machine's, never the definition's (ADR 0112 §1). Each
+// element of `groups` is a whole placeholder or a whole number; a placeholder is filled with the number the
+// config value holds, and the list reaches the node-engine as numbers.
+
+// groupSide is one element of a container's groups: a whole placeholder or a whole number.
+var groupSide = regexp.MustCompile(`^(?:\$\{setting:[a-z0-9][a-z0-9_.-]*\}|[0-9]+)$`)
+
+// groupsOf is a container resource's groups as the manifest wrote them (text or numbers), none when it names none.
+func groupsOf(r map[string]any) []any {
+	groups, _ := r["groups"].([]any)
+	return groups
+}
+
+// GroupSettingProblems refuses, where a manifest is read, a container whose groups hold anything but whole
+// placeholders and whole numbers, or a placeholder whose key the module neither declares nor asks for elsewhere.
+func GroupSettingProblems(m Manifest) []string {
+	var problems []string
+	for _, r := range m.Resources {
+		if fmt.Sprint(r["type"]) != "container" {
+			continue
+		}
+		for _, g := range groupsOf(r) {
+			s, isText := g.(string)
+			if !isText {
+				continue // a number: the declaration judges its value
+			}
+			if !groupSide.MatchString(s) {
+				problems = append(problems, fmt.Sprintf("%s: the container %v's group %q is not a whole "+
+					"${config:key} or a whole number: a supplementary group is a number, and nothing else is "+
+					"written into it (novox/hq ADR 0480 clause 7)", m.Module, r["id"], s))
+				continue
+			}
+			if m.Templated() {
+				continue
+			}
+			for _, key := range settingsUsed(s) {
+				if _, declared := m.Settings[key]; !declared && !m.DeclaresConfig() {
+					continue // the settings form judges its own keys
+				}
+				if _, declared := m.Settings[key]; !declared {
+					problems = append(problems, fmt.Sprintf("%s: the container %v's group says ${config:%s}, and the module "+
+						"declares no such value (novox/hq ADR 0348 §4)", m.Module, r["id"], key))
+				}
+			}
+		}
+	}
+	return problems
+}
+
+// settingIntoGroups fills ${setting:…} in a container's groups, refusing — with the key and why, the resource left as
+// it was — a key nothing sets and a value that is not a whole number above zero. A number is kept; the list that
+// results is numbers alone.
+func settingIntoGroups(resource map[string]any, layers []Layer, module string) error {
+	groups := groupsOf(resource)
+	if len(groups) == 0 {
+		return nil
+	}
+	filled := make([]any, 0, len(groups))
+	for _, g := range groups {
+		s, isText := g.(string)
+		if !isText {
+			if f, isNumber := g.(float64); isNumber && f == float64(int(f)) {
+				g = int(f) // a number the manifest wrote, as the numbers a placeholder gives
+			}
+			filled = append(filled, g)
+			continue
+		}
+		keys := settingsUsed(s)
+		if len(keys) != 1 || settingRef.ReplaceAllString(s, "") != "" {
+			filled = append(filled, g) // not a whole placeholder: the manifest check refuses it
+			continue
+		}
+		key := keys[0]
+		value, set := settingValue(layers, key)
+		if !set {
+			return &UnsetSettingError{Module: module, Setting: key,
+				where: fmt.Sprintf("a container %v whose groups", resource["id"]), setToday: orNoSettings(layers),
+				said: fmt.Sprintf(
+					"%s has a container %v whose groups say ${setting:%s}, and nothing sets %q for it — an operator's "+
+						"value is the assignment's, never the definition's (novox/hq ADR 0112): "+
+						"`settings set %s <file>` with {%q: …}%s",
+					module, resource["id"], key, key, module, key, orNoSettings(layers))}
+		}
+		v := plainly(value)
+		id, whole := wholeID(v)
+		if !whole || id == 0 {
+			return fmt.Errorf("%s: the setting %q is %q, which cannot be a group of the container %v: a supplementary "+
+				"group is a whole number above zero, never a name or other text (novox/hq ADR 0480 clause 7, ADR 0328 §15)",
+				module, key, v, resource["id"])
+		}
+		filled = append(filled, int(id))
+	}
+	resource["groups"] = filled
+	return nil
+}

vendor/git.novox.be/novox/mesh-sdk/go/catalogue/unconsumed_placeholder.go

@@ -56,7 +56,7 @@ type filler struct {
 // seatInto, machineInto and contributionsInto. A pass that comes to read another field adds it here,
 // or the sweep refuses the placeholder it would have filled.
 var fillers = []filler{
-	{namespace: "setting", patterns: []*regexp.Regexp{settingRef}, fields: map[string][]string{"file": {"content"}, "service": {"unit"}, "directory": {"owner"}}},
+	{namespace: "setting", patterns: []*regexp.Regexp{settingRef}, fields: map[string][]string{"file": {"content"}, "service": {"unit"}, "directory": {"owner"}, "container": {"groups"}}},
 	{namespace: "dir", patterns: []*regexp.Regexp{dirRef}, fields: map[string][]string{"*": {"path", "content", "volumes", "env", "env-file"}}},
 	{namespace: "access", patterns: []*regexp.Regexp{accessRef}, fields: map[string][]string{"*": {"path", "content", "volumes", "env", "env-file"}}},
 	{namespace: "secret", patterns: []*regexp.Regexp{placeholder}, fields: map[string][]string{"file": {"content"}},

vendor/git.novox.be/novox/mesh-sdk/go/declaration/declaration.go

@@ -324,6 +324,15 @@ type File struct {
 	// depend on a field somewhere else.
 	Bytes string `json:"bytes,omitempty"`
 
+	// Digest and Size say the content is not carried but fetched: a file over FileReferenceThreshold travels as
+	// the sha256 digest of its content, "sha256:<64 hex>", and its size in bytes, in place of Content or Bytes
+	// (novox/hq ADR 0486 §1). The node-engine fetches the object of that name from FileBucketFor(node), checks what it
+	// received against Digest and Size, and only then writes the file. Exclusive with Content, Sealed, Bytes,
+	// VaultSealed and Secrets; sent only to an engine that reports FileReferencesCapability, as an older engine
+	// refuses a field it does not know, whole.
+	Digest string `json:"digest,omitempty"`
+	Size   int64  `json:"size,omitempty"`
+
 	// Owner is the user this belongs to, by name. Absent means root.
 	Owner string `json:"owner,omitempty"`
 
@@ -465,6 +474,10 @@ func (f *File) validate(where string, _ bool) []string {
 			problems = append(problems, where+": a file the vault sealed whole has no holes for secrets")
 		}
 	}
+	problems = append(problems, f.checkReference(where)...)
+	if f.Digest != "" || f.Size != 0 {
+		said = append(said, "digest")
+	}
 	if len(said) > 1 {
 		sort.Strings(said)
 		problems = append(problems, where+
@@ -1454,6 +1467,14 @@ type Container struct {
 	// container runs as its image says. Its key is `identity`, the manifest's word; the field is not, because
 	// a resource's Identity is its id.
 	RunAs *ContainerIdentity `json:"identity,omitempty"`
+
+	// Groups are the supplementary groups the container's process joins, as numbers, each passed to the runtime
+	// as a group to add (novox/hq ADR 0480 clause 7, issue 1636): n8n writes the media library through the
+	// library's group, which a stock image knows nothing of. Each is above zero and below the kernel's "no group"
+	// (ADR 0328 §15: never root). Part of the spec, so a change recreates the container. Absent: none are added.
+	// An older node-engine refuses the key (strict decoding), so the controller sends it only to a node that
+	// reports it reads it.
+	Groups []int64 `json:"groups,omitempty"`
 }
 
 // The ways an image is told who to run as (novox/hq ADR 0325 §2).
@@ -1521,6 +1542,30 @@ func (i *ContainerIdentity) problems(where string, env map[string]string) []stri
 	return problems
 }
 
+// groupProblems refuses a supplementary group that is root's or below it, the kernel's "no group" number, or a
+// number named twice (novox/hq ADR 0480 clause 7, ADR 0328 §15).
+func (c *Container) groupProblems(where string) []string {
+	var problems []string
+	seen := map[int64]bool{}
+	for _, g := range c.Groups {
+		switch {
+		case g == 0:
+			problems = append(problems, fmt.Sprintf("%s: container %s adds group 0, and the mesh never makes or keeps anything "+
+				"as root: a supplementary group is never root's (novox/hq ADR 0328 §15)", where, c.Name))
+		case g < 0:
+			problems = append(problems, fmt.Sprintf("%s: container %s adds group %d, below zero: a group is a whole number "+
+				"above zero", where, c.Name, g))
+		case g >= 1<<32-1:
+			problems = append(problems, fmt.Sprintf("%s: container %s adds group %d, which is the kernel's \"no group\" "+
+				"number or beyond it", where, c.Name, g))
+		case seen[g]:
+			problems = append(problems, fmt.Sprintf("%s: container %s adds group %d twice", where, c.Name, g))
+		}
+		seen[g] = true
+	}
+	return problems
+}
+
 func (c *Container) Identity() string { return c.ID }
 func (c *Container) Kind() Type       { return TypeContainer }
 func (c *Container) Target() string   { return c.Name }
@@ -1603,6 +1648,7 @@ func (c *Container) validate(where string, _ bool) []string {
 			"runs and exits, and joins nothing afterwards")
 	}
 	problems = append(problems, c.RunAs.problems(where+": container "+c.Name, c.Env)...)
+	problems = append(problems, c.groupProblems(where)...)
 	return append(problems, checkImage(where, c.Image)...)
 }
 

vendor/git.novox.be/novox/mesh-sdk/go/declaration/filereference.go

@@ -0,0 +1,150 @@
+package declaration
+
+import (
+	"crypto/sha256"
+	"encoding/base64"
+	"encoding/hex"
+	"fmt"
+	"regexp"
+)
+
+// The three names of a file travelling by digest (novox/hq ADR 0486 §1, §2, §5), shared by the node-engine that
+// reads them and the controller that writes them.
+const (
+	// FileReferenceThreshold is the size above which a file travels by digest: a file of this many bytes or fewer
+	// stays in the declaration as it is.
+	FileReferenceThreshold = 64 * 1024
+	// FileBucketPrefix starts the name of a node's object bucket, FileBucketFor(node), which holds the contents of the
+	// files of that node's declaration, each under the hex of its sha256 digest (ObjectName). One bucket per node,
+	// so a grant names it and a literal `*` is never needed (ADR 0486 §2, changed by ADR 0488 §1 and §2). The controller alone writes it; the
+	// node's engine reads an object by name.
+	FileBucketPrefix = "declaration-files-"
+	// FileStreamPrefix starts the name of the stream behind such a bucket, which the bus's grants name.
+	FileStreamPrefix = "OBJ_"
+	// FileReferencesCapability is what a node-engine reports when it reads a file given as a digest and size.
+	FileReferencesCapability = "file-references"
+)
+
+var nodeToken = regexp.MustCompile(`^[A-Za-z0-9_-]+$`)
+
+// FileBucketFor is the name of the object bucket of a node's files, "declaration-files-<node>" (novox/hq ADR 0488
+// §4, which replaces the single bucket constant of issue 1694). The node name must be a name the bus accepts in a
+// bucket and in a subject token: letters, digits, '_' and '-', so no '.', '*', '>' or space.
+func FileBucketFor(node string) (string, error) {
+	if !nodeToken.MatchString(node) {
+		return "", fmt.Errorf("node %q; a node's bucket is named by letters, digits, '_' and '-' only", node)
+	}
+	return FileBucketPrefix + node, nil
+}
+
+// FileStreamFor is the name of the stream behind a node's bucket, "OBJ_" and the bucket's name.
+func FileStreamFor(node string) (string, error) {
+	b, err := FileBucketFor(node)
+	if err != nil {
+		return "", err
+	}
+	return FileStreamPrefix + b, nil
+}
+
+var digestForm = regexp.MustCompile(`^sha256:[0-9a-f]{64}$`)
+
+// DigestOf is the digest a reference names for a content: "sha256:<64 lower-case hex>".
+func DigestOf(content []byte) string {
+	sum := sha256.Sum256(content)
+	return "sha256:" + hex.EncodeToString(sum[:])
+}
+
+// ObjectName is the name of the object holding the content a digest names: the hex without its "sha256:" prefix.
+func ObjectName(digest string) (string, error) {
+	if !digestForm.MatchString(digest) {
+		return "", fmt.Errorf("digest %q is not sha256:<64 lower-case hex characters>", digest)
+	}
+	return digest[len("sha256:"):], nil
+}
+
+// IsReference reports whether the file gives its content as a digest and size instead of carrying it.
+func (f *File) IsReference() bool { return f.Digest != "" }
+
+// checkReference judges the digest and size, and what a reference may not be given with.
+func (f *File) checkReference(where string) []string {
+	if f.Digest == "" && f.Size == 0 {
+		return nil
+	}
+	var problems []string
+	if !digestForm.MatchString(f.Digest) {
+		problems = append(problems, fmt.Sprintf("%s: digest %q; a file by reference names its content as "+
+			"sha256:<64 lower-case hex characters>", where, f.Digest))
+	}
+	if f.Size <= 0 {
+		problems = append(problems, fmt.Sprintf("%s: size %d; a file by reference states its size in bytes, "+
+			"more than zero", where, f.Size))
+	}
+	if f.Content != "" || f.Bytes != "" || f.Sealed != "" || f.VaultSealed != nil || len(f.Secrets) > 0 {
+		problems = append(problems, where+": a file by reference carries its content in the object its digest "+
+			"names, so it says no content, bytes, sealed, vault-sealed or secrets")
+	}
+	if f.Into != "" {
+		problems = append(problems, where+": a file by reference is written whole; a file written into says its "+
+			"part in content")
+	}
+	return problems
+}
+
+// Body is the bytes the file's content stands for: its content, or its bytes decoded.
+func (f *File) Body() ([]byte, error) {
+	if f.Bytes == "" {
+		return []byte(f.Content), nil
+	}
+	b, err := base64.StdEncoding.DecodeString(f.Bytes)
+	if err != nil {
+		return nil, fmt.Errorf("file %s: bytes are not base64: %w", f.ID, err)
+	}
+	return b, nil
+}
+
+// TravelsByDigest reports whether the controller may put this file's content in the bucket: it is plain content
+// or bytes (not sealed, not filled with secrets, not written into another file) of more than FileReferenceThreshold
+// bytes.
+func (f *File) TravelsByDigest() bool {
+	if f.IsReference() || f.Sealed != "" || f.VaultSealed != nil || len(f.Secrets) > 0 || f.Into != "" {
+		return false
+	}
+	if f.Bytes != "" {
+		// DecodedLen counts padding, so the exact length is taken off the decoded bytes.
+		body, err := f.Body()
+		return err == nil && len(body) > FileReferenceThreshold
+	}
+	return len(f.Content) > FileReferenceThreshold
+}
+
+// AsReference is the file as it is sent to an engine that reports FileReferencesCapability: a copy with the digest
+// and size in place of the content, and the content the controller puts into the bucket under ObjectName(digest).
+// A file that does not travel by digest is refused, not passed through, so a caller cannot send a small file empty.
+func (f *File) AsReference() (File, []byte, error) {
+	if !f.TravelsByDigest() {
+		return File{}, nil, fmt.Errorf("file %s does not travel by digest", f.ID)
+	}
+	body, err := f.Body()
+	if err != nil {
+		return File{}, nil, err
+	}
+	ref := *f
+	ref.Content, ref.Bytes = "", ""
+	ref.Digest, ref.Size = DigestOf(body), int64(len(body))
+	return ref, body, nil
+}
+
+// Verify checks what was fetched against the digest and size the file names; the node-engine writes the file only
+// after it returns nil. A mismatch is the apply's failure, never a partial apply (ADR 0486 §1).
+func (f *File) Verify(body []byte) error {
+	if !f.IsReference() {
+		return fmt.Errorf("file %s is not given by reference", f.ID)
+	}
+	if int64(len(body)) != f.Size {
+		return fmt.Errorf("file %s: the object is %d bytes and the declaration says %d", f.ID, len(body), f.Size)
+	}
+	if got := DigestOf(body); got != f.Digest {
+		return fmt.Errorf("file %s: the object hashes to %s and the declaration names %s", f.ID, got, f.Digest)
+	}
+	return nil
+}

vendor/git.novox.be/novox/mesh-sdk/go/delivery/buildrecord.go

@@ -25,7 +25,7 @@ type BuildRecord struct {
 }
 
 // Artifact is one thing a build made: mesh-controller internal/chain/records.go Artifact, json keys name, kind and
-// reference, nothing else (novox/hq ADR 0478 clause 7).
+// reference, nothing else (novox/hq ADR 0478 clause 8).
 type Artifact struct {
 	Name      string `json:"name"`
 	Kind      string `json:"kind"`

vendor/git.novox.be/novox/mesh-sdk/go/delivery/source.go

@@ -389,11 +389,20 @@ type Module struct {
 	Src        uint64       `json:"src,omitempty"`
 	Repository string       `json:"repository"`
 	Commit     string       `json:"commit"`
-	// Path is the module's directory in its repository, trimmed of slashes, empty when its manifest is the repository's
-	// root (novox/hq ADR 0478 clause 8): the build tools need it. A value written before has none.
+	// Path is the module's directory in its repository, trimmed of slashes, and RootPath (".") when its manifest is the
+	// repository's root (novox/hq ADR 0478 clause 9, issue 1615): the build tools need it. Empty means not known: a value
+	// written before the indexer learned paths has none.
 	Path string `json:"path,omitempty"`
+	// Toolchains are the toolchains FP2 was computed with, by language (go, typescript): the version installed and the
+	// build module's recipe version the build nodes agreed on then (novox/hq ADR 0477 clause 2, ADR 0478 clause 3). A builder
+	// builds the fingerprint only with these. Empty when FP2 is empty or the module has no toolchain; a value written
+	// before has none (issue 1615).
+	Toolchains map[string]ToolchainUsed `json:"toolchains,omitempty"`
 }
 
+// RootPath is Module.Path of a module whose manifest is its repository's root.
+const RootPath = "."
+
 // KeptInputs2 are SourceInputs2 without the module's name (the key has it) and without toolchains (those come from
 // the build modules' toolchain keys when the fingerprint is computed): what a Module keeps of a merge.
 type KeptInputs2 struct {
@@ -421,6 +430,11 @@ func (m Module) check() error {
 	case m.FP2 != "" && m.None2 != "":
 		return fmt.Errorf("delivery: a module has both fp2 and none2")
 	}
+	for language, t := range m.Toolchains {
+		if t.Version == "" || t.Recipe == "" {
+			return fmt.Errorf("delivery: the module's toolchain of %q needs its version and its recipe version", language)
+		}
+	}
 	if m.Inputs2 != nil && m.Manifest == "" {
 		return fmt.Errorf("delivery: a module keeps new-form inputs but has no manifest digest")
 	}

vendor/modules.txt

@@ -1,4 +1,4 @@
-# git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261021093645-465beb4ea5e3
+# git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261021134822-86f9a1a5c508
 ## explicit; go 1.26.0
 git.novox.be/novox/mesh-sdk/go/asks
 git.novox.be/novox/mesh-sdk/go/catalogue