Merge pull request 'A module's process may hold a bus account of its own, and a module stream may be a work queue (ADR 0436, issues 1170, 1177-1181)' (#390) from feat/mail-sender-controller into main

internal/broker/derived.go

@@ -190,18 +190,33 @@ func ConsumersOf(users []Principal) []ModuleConsumer {
 	var out []ModuleConsumer
 	seen := map[string]bool{}
 	add := func(p Principal) {
-		c, needed := ConsumerFor(p)
-		if !needed || seen[p.Node+"/"+p.Module] {
+		key := p.Node + "/" + p.Module
+		if seen[key] {
 			return
 		}
-		seen[p.Node+"/"+p.Module] = true
-		out = append(out, ModuleConsumer{Node: p.Node, Module: p.Module, Consumer: c})
-		// And one on each module stream it hears (novox/hq ADR 0363 §5).
-		for _, h := range p.Hears {
-			if len(h.Filters) == 0 {
-				continue
+		c, needed := ConsumerFor(p)
+		// **A module with a work-queue consumer of its own needs no other reason to be visited here**
+		// (novox/hq ADR 0436 §1, §2, §6): mesh-mail's sender consumes and watches nothing of its own, so
+		// ConsumerFor alone would have found nothing needed and skipped it before its one queue consumer
+		// was ever composed.
+		if !needed && len(p.Queues) == 0 {
+			return
+		}
+		seen[key] = true
+		if needed {
+			out = append(out, ModuleConsumer{Node: p.Node, Module: p.Module, Consumer: c})
+			// And one on each module stream it hears (novox/hq ADR 0363 §5).
+			for _, h := range p.Hears {
+				if len(h.Filters) == 0 {
+					continue
+				}
+				out = append(out, ModuleConsumer{Node: p.Node, Module: p.Module, Consumer: heardConsumer(p, h)})
 			}
-			out = append(out, ModuleConsumer{Node: p.Node, Module: p.Module, Consumer: heardConsumer(p, h)})
+		}
+		// And the one durable consumer of each of its own work-queue streams, for the one process its
+		// bus.queues names (novox/hq ADR 0436 §1, §2, §6).
+		for _, q := range p.Queues {
+			out = append(out, ModuleConsumer{Node: p.Node, Module: p.Module, Consumer: QueueConsumer(p, q)})
 		}
 	}
 	for _, p := range users {
@@ -214,9 +229,13 @@ func ConsumersOf(users []Principal) []ModuleConsumer {
 			continue
 		}
 		for _, d := range p.Carries {
+			// **A carried module's work-queue consumer is still the controller's to make** (novox/hq ADR
+			// 0436 §1, §2, §6), the same reason its ordinary consumer is (ADR 0198): mesh-mail has no
+			// account of its own (NoAccount) and is carried here, but its process does, and the consumer
+			// it reads through must exist and survive PruneHeard whether or not the module itself speaks.
 			add(Principal{Kind: KindModule, Node: p.Node, Module: d.Module, Emits: d.Emits,
 				Consumes: d.Consumes, Serves: d.Serves, Holds: d.Holds, Uses: d.Uses, Watches: d.Watches,
-				Streams: d.Streams, Hears: ComposedHears(d)})
+				Streams: d.Streams, Hears: ComposedHears(d), Queues: d.Queues})
 		}
 	}
 	return out

internal/broker/jetstream.go

@@ -154,16 +154,10 @@ func Borrow(j *JetStream) *JetStream {
 	return &lent
 }
 
-// EnsureStream creates the stream if it is absent and brings it to match if it is present.
-//
-// **Idempotent, because the controller asserts on every start** rather than creating once at
-// genesis: a stream somebody deleted, or a mesh raised from a restored backup, has to converge
-// rather than run without the guarantee its messages assume.
-//
-// An update, not a delete and recreate. Recreating would discard every message the stream holds
-// and every consumer's position in it — which for CONTROL means the pushes being held through a
-// store restart, exactly the guarantee the stream exists for.
-func (j *JetStream) EnsureStream(s Stream) error {
+// StreamConfigFor is the server's own config for one of the mesh's streams, pure so the shape it builds —
+// not least the restricted metadata a work-queue or a grant-restricted stream's dead letters age and hide
+// by (novox/hq ADR 0436 §6, ADR 0376 §3) — is testable without a server.
+func StreamConfigFor(s Stream) *nats.StreamConfig {
 	want := &nats.StreamConfig{
 		Name:              s.Name,
 		Subjects:          s.Subjects,
@@ -174,8 +168,14 @@ func (j *JetStream) EnsureStream(s Stream) error {
 	}
 	want.AllowDirect = s.Direct
 	want.AllowMsgTTL = s.AllowMsgTTL
-	if s.Restricted {
-		want.Metadata = map[string]string{RestrictedMetadata: "true"}
+	if s.Restricted || s.WorkQueue {
+		want.Metadata = map[string]string{}
+		if s.Restricted {
+			want.Metadata[RestrictedMetadata] = "true"
+		}
+		if s.WorkQueue {
+			want.Metadata[WorkQueueMetadata] = "true"
+		}
 	}
 	if s.MaxBytes > 0 {
 		want.MaxBytes = s.MaxBytes
@@ -193,6 +193,20 @@ func (j *JetStream) EnsureStream(s Stream) error {
 		want.MaxMsgsPerSubject = 1
 		want.MaxAge = 0
 	}
+	return want
+}
+
+// EnsureStream creates the stream if it is absent and brings it to match if it is present.
+//
+// **Idempotent, because the controller asserts on every start** rather than creating once at
+// genesis: a stream somebody deleted, or a mesh raised from a restored backup, has to converge
+// rather than run without the guarantee its messages assume.
+//
+// An update, not a delete and recreate. Recreating would discard every message the stream holds
+// and every consumer's position in it — which for CONTROL means the pushes being held through a
+// store restart, exactly the guarantee the stream exists for.
+func (j *JetStream) EnsureStream(s Stream) error {
+	want := StreamConfigFor(s)
 
 	switch _, err := j.js.StreamInfo(s.Name); {
 	case err == nil:

internal/broker/modstream_work_queue_test.go

@@ -0,0 +1,81 @@
+package broker
+
+import "testing"
+
+// mailSendsStream is mesh-mail's future `mail-sends` stream (novox/hq ADR 0436 §7, §8), as the bus holds it:
+// work-queue retention, a 24-hour duplicate window, kept one day and at most 64 MiB.
+var mailSendsStream = ModuleStream{Module: "mesh-mail", Name: "MAIL_SENDS",
+	Events: []string{"mail.send.approved"}, MaxAgeDays: 1, MaxMiB: 64, WorkQueue: true, Duplicates: 24}
+
+// 1177/AC1: a work-queue stream is composed with work-queue retention, refusing a new message when full
+// (DiscardNew), a 24-hour duplicate window, a one-day maximum age and a 64 MiB cap.
+func TestAWorkQueueStreamIsComposedToRefuseWhenFull(t *testing.T) {
+	s := mailSendsStream.Stream()
+	if s.Retention != RetentionWorkQueue {
+		t.Fatalf("retention: %v, want %v", s.Retention, RetentionWorkQueue)
+	}
+	if !s.DiscardNew {
+		t.Fatal("a work-queue stream did not refuse a new message when full")
+	}
+	if s.DuplicatesSeconds != 24*60*60 {
+		t.Fatalf("duplicate window: %d seconds, want %d (24 hours)", s.DuplicatesSeconds, 24*60*60)
+	}
+	if s.MaxAge != 24*60*60 {
+		t.Fatalf("max age: %d seconds, want %d (1 day)", s.MaxAge, 24*60*60)
+	}
+	if s.MaxBytes != 64<<20 {
+		t.Fatalf("max bytes: %d, want %d (64 MiB)", s.MaxBytes, 64<<20)
+	}
+}
+
+// 1177/AC3: a stream with no work-queue clause composes exactly as main does: limits retention, dropping its
+// oldest, never refusing a new message.
+func TestANonWorkQueueStreamStillDropsItsOldest(t *testing.T) {
+	s := mailStream.Stream()
+	if s.Retention != RetentionLimits || s.DiscardNew || s.DuplicatesSeconds != 0 {
+		t.Fatalf("composed as %+v; want limits retention, never discarding new, no duplicate window", s)
+	}
+}
+
+// 1178/AC1: the process a work-queue stream's bus.queues names gets exactly one durable consumer,
+// <node>_<module>_<process id>, with the stream's declared max-deliver — composed even though mesh-mail's
+// sender otherwise consumes and watches nothing of its own, which alone would give ConsumerFor nothing
+// needed. Explicit acknowledgement is EnsureConsumer's own rule for every consumer it makes (jetstream.go),
+// so it is not re-asserted here.
+func TestTheOneProcessAWorkQueuesBusNamesGetsItsOwnConsumer(t *testing.T) {
+	sender := Principal{Kind: KindModule, Node: "novox", Module: "mesh-mail", PasswordHash: "x",
+		Queues: []QueueOwner{{Process: "send", Stream: "MAIL_SENDS", MaxDeliver: 5}}}
+	got := ConsumersOf([]Principal{sender})
+	if len(got) != 1 {
+		t.Fatalf("mesh-mail's consumers: %+v", got)
+	}
+	c := got[0].Consumer
+	if c.Name != "novox_mesh-mail_send" || c.Stream != "MAIL_SENDS" || c.MaxDeliver != 5 {
+		t.Fatalf("the queue's consumer: %+v", c)
+	}
+}
+
+// review round 1, finding 2 (1178): mesh-mail's real shape has no account of its own (NoAccount) and is
+// carried by the machine's tool runner — so its queue consumer has to come from the carried-module path in
+// ConsumersOf, not only from a module with its own principal, or PruneHeard would remove what issueProcess
+// made for it (novox/hq ADR 0436 §1, §2, §6).
+func TestAWorkQueueConsumerSurvivesForAModuleTheRuntimeCarries(t *testing.T) {
+	users, err := Users(Records{Nodes: []string{"novox"}, Assigned: map[string][]Declared{"novox": {
+		{Module: RuntimeModule},
+		{Module: "mesh-mail", NoAccount: true,
+			Queues: []QueueOwner{{Process: "send", Stream: "MAIL_SENDS", MaxDeliver: 5}}},
+	}}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	got := ConsumersOf(users)
+	var found bool
+	for _, c := range got {
+		if c.Module == "mesh-mail" && c.Consumer.Name == "novox_mesh-mail_send" && c.Consumer.Stream == "MAIL_SENDS" {
+			found = true
+		}
+	}
+	if !found {
+		t.Fatalf("mesh-mail's queue consumer is missing from the carried module's composition: %+v", got)
+	}
+}

internal/broker/modstreams.go

@@ -49,6 +49,12 @@ type ModuleStream struct {
 	MaxMiB     int
 	// Restricted says a trusted config value of the module grants who hears it (ADR 0363 §4).
 	Restricted bool
+	// WorkQueue says this stream holds ADR 0436 §6's work-queue retention: a message is removed once a
+	// consumer acknowledges it, and the bus refuses a new one when full rather than dropping its oldest.
+	WorkQueue bool
+	// Duplicates is the work-queue's duplicate window in hours (novox/hq ADR 0436 §6); meaningless unless
+	// WorkQueue.
+	Duplicates int
 }
 
 // Subjects are the subjects the stream takes.
@@ -70,7 +76,11 @@ func (s ModuleStream) Stream() Stream {
 	if s.Restricted {
 		why += "; heard only by the consumers its trusted config value grants"
 	}
-	return Stream{
+	if s.WorkQueue {
+		why += "; a work-queue (novox/hq ADR 0436 §6): a message is removed once its one consumer " +
+			"acknowledges it, and a full stream refuses a new one rather than dropping what it holds"
+	}
+	out := Stream{
 		Name:      s.Name,
 		Subjects:  s.Subjects(),
 		Retention: RetentionLimits,
@@ -80,6 +90,50 @@ func (s ModuleStream) Stream() Stream {
 		// Said on the bus, so a dead letter kept from it ages out with it (novox/hq ADR 0376 §3).
 		Restricted: s.Restricted,
 	}
+	if s.WorkQueue {
+		out.Retention = RetentionWorkQueue
+		out.DiscardNew = true
+		out.DuplicatesSeconds = s.Duplicates * 60 * 60
+		// Said on the bus too, reusing the one flag a restricted stream's dead letters already age and hide
+		// by (novox/hq ADR 0436 §6, ADR 0376 §3-4): a work-queue stream's grant is always empty (ADR 0436
+		// §6 refuses one that carries a grant), so this never collides with a trusted-config restriction.
+		out.Restricted = true
+		// And its own metadata, apart from the bus's work-queue retention SEAT_* and other mesh-internal
+		// streams share without being one of this clause's: only this flag says a dead letter kept from the
+		// stream is drop-only (novox/hq ADR 0436 §6), never the stream's Retention alone.
+		out.WorkQueue = true
+	}
+	return out
+}
+
+// QueueOwner is the one process of a module that is the durable consumer of one of its own work-queue
+// streams (novox/hq ADR 0436 §1, §2, §6): named in that process's bus.queues, and checked at registration
+// to be the only one (catalogue.WorkQueueStreamProblems).
+type QueueOwner struct {
+	// Process is the process resource's id — its bus account's name, with the node and module (novox/hq ADR
+	// 0436 §2).
+	Process string
+	// Stream is the work-queue stream's name on the bus.
+	Stream string
+	// MaxDeliver bounds how many times a message is handed over before it is given up as a dead letter
+	// (novox/hq ADR 0436 §6).
+	MaxDeliver int
+}
+
+// QueueConsumer is the durable consumer the one process a module's bus.queues names is granted on its own
+// work-queue stream (novox/hq ADR 0436 §1, §2, §6): no filter, since it is the stream's only consumer —
+// unlike heardConsumer, which is one of possibly several hearing a module's ordinary stream.
+func QueueConsumer(p Principal, q QueueOwner) Consumer {
+	return Consumer{
+		Name:           p.Node + "_" + p.Module + "_" + q.Process,
+		Stream:         q.Stream,
+		AckWaitSeconds: 30,
+		MaxDeliver:     q.MaxDeliver,
+		Why: fmt.Sprintf("%s's process %s is the one consumer %s's bus.queues names for its work-queue "+
+			"stream %s (novox/hq ADR 0436 §6); after max-deliver %d it gives a message up, and the "+
+			"controller keeps it in %s, offered only drop", p.Module, q.Process, p.Module, q.Stream,
+			q.MaxDeliver, DeadLettersStream),
+	}
 }
 
 // ModuleStreams is every declared module stream as the controller asserts it, in name order.

internal/broker/modstreams_workqueue_integration_test.go

@@ -0,0 +1,101 @@
+//go:build integration
+
+package broker
+
+import (
+	"testing"
+	"time"
+
+	"github.com/nats-io/nats.go"
+	"github.com/nats-io/nats.go/jetstream"
+
+	"github.com/novox/mesh-controller/internal/testbus"
+)
+
+// 1178/AC4, on a real bus: the controller ensuring mesh-mail's work-queue stream and its one consumer gives
+// the bus's own guarantees — a duplicate publish within the window is taken once, a message naked past
+// max-deliver is not handed over again, and a full stream refuses a new publish (ADR 0436 §6).
+//
+//	go test -tags integration ./internal/broker/ -run TestAWorkQueueStreamOnARealBus
+func TestAWorkQueueStreamOnARealBus(t *testing.T) {
+	js, err := Dial(testbus.URL(t))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer js.Close()
+
+	// Small enough that a handful of messages fill it, so "the stream is full" is reachable within a test.
+	stream := ModuleStream{Module: "mesh-mail", Name: "MAIL_SENDS", Events: []string{"mail.send.approved"},
+		MaxAgeDays: 1, MaxMiB: 1, WorkQueue: true, Duplicates: 1}
+	if err := js.EnsureStream(stream.Stream()); err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { _ = js.Context().DeleteStream(stream.Name) })
+
+	owner := QueueOwner{Process: "send", Stream: stream.Name, MaxDeliver: 5}
+	sender := Principal{Kind: KindModule, Node: "novox", Module: "mesh-mail", PasswordHash: "x"}
+	consumer := QueueConsumer(sender, owner)
+	consumer.AckWaitSeconds = 1
+	if err := js.EnsureConsumer(consumer); err != nil {
+		t.Fatal(err)
+	}
+
+	subject := ModuleStreamSubject("mesh-mail", "mail.send.approved")
+
+	// A duplicate publish within the window is kept once (ADR 0436 §6's duplicate window).
+	publish := func(id string, size int) (*nats.PubAck, error) {
+		return js.Context().Publish(subject, make([]byte, size), nats.MsgId(id))
+	}
+	if _, err := publish("dup-1", 16); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := publish("dup-1", 16); err != nil {
+		t.Fatal(err)
+	}
+	if info, err := js.Context().StreamInfo(stream.Name); err != nil || info.State.Msgs != 1 {
+		t.Fatalf("a message published twice with the same id: %v msgs, err %v; want 1", info, err)
+	}
+
+	// Naked five times, the consumer is not handed the message a sixth time.
+	api, err := jetstream.New(js.Conn())
+	if err != nil {
+		t.Fatal(err)
+	}
+	reading, err := api.Consumer(t.Context(), stream.Name, consumer.Name)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for i := 0; i < owner.MaxDeliver; i++ {
+		batch, err := reading.Fetch(1, jetstream.FetchMaxWait(2*time.Second))
+		if err != nil {
+			t.Fatal(err)
+		}
+		got := false
+		for msg := range batch.Messages() {
+			got = true
+			_ = msg.Nak()
+		}
+		if !got {
+			t.Fatalf("delivery %d of %d never arrived", i+1, owner.MaxDeliver)
+		}
+	}
+	batch, err := reading.Fetch(1, jetstream.FetchMaxWait(2*time.Second))
+	if err != nil {
+		t.Fatal(err)
+	}
+	for range batch.Messages() {
+		t.Fatalf("the message was delivered a %dth time, past its max-deliver of %d", owner.MaxDeliver+1, owner.MaxDeliver)
+	}
+
+	// Full, the stream refuses a new publish rather than dropping what it holds (DiscardNew).
+	var fullErr error
+	for i := 0; i < 1<<16; i++ {
+		if _, err := publish("fill-"+time.Now().String(), 1<<16); err != nil {
+			fullErr = err
+			break
+		}
+	}
+	if fullErr == nil {
+		t.Fatal("a work-queue stream accepted every publish; want it to refuse one once full")
+	}
+}

internal/broker/nats.go

@@ -48,6 +48,11 @@ const (
 	// service of the module holding NodeProvisionerSeat, outside the tool runner, under an account of its own so
 	// the vault can tell it from an agent. Its authority is provisionerGrants and nothing else.
 	KindProvisioner Kind = "provisioner"
+	// KindProcess is one process of a module that declares bus (novox/hq ADR 0436 §1, §2): a service of that
+	// module, outside the tool runner and outside the module's own account, under a bus account scoped to
+	// exactly what its bus says — never root, never the operator account, and never able to answer a tool
+	// call or a seat's verb (§3). One per process and machine.
+	KindProcess Kind = "process"
 )
 
 // RuntimeModule is the module that IS the node's tool runtime (novox/hq ADR 0175). Where it is
@@ -95,6 +100,9 @@ type Principal struct {
 	Kind   Kind
 	Node   string
 	Module string
+	// Process is the process resource's id, for a KindProcess principal alone (novox/hq ADR 0436 §2):
+	// Username and inbox are <node>.<module>.<process id>.
+	Process string
 
 	Emits    []string
 	Consumes []string
@@ -170,6 +178,12 @@ type Principal struct {
 	// subjects it was granted (novox/hq ADR 0363).
 	Streams []ModuleStream
 	Hears   []Heard
+	// Queues are its own work-queue streams and the one process each is the consumer of (novox/hq ADR 0436
+	// §1, §2, §6); for a KindProcess principal, its own alone.
+	Queues []QueueOwner
+	// Asks says a KindProcess principal reads the records of its module's own asks (novox/hq ADR 0436 §1),
+	// on whichever seat of Uses keeps them (novox/hq ADR 0259 §3) — never set for any other kind.
+	Asks bool
 
 	// SnapshotsTheBus is the bus's own module, the one holding mesh-broker (novox/hq ADR 0235). Its
 	// whole authority is BusSnapshotGrants: it copies the streams for the night's backup and nothing
@@ -446,6 +460,10 @@ func (p Principal) Username() string {
 		// issues its credential through the same path a module's takes (`module issue`), and
 		// that path knows the node and the module, not the kind.
 		return p.Node + "." + p.Module
+	case KindProcess:
+		// One account per process and machine (novox/hq ADR 0436 §2): `<machine>.<module>.<process id>`,
+		// never the module's own name alone, which is a different account with a different secret.
+		return p.Node + "." + p.Module + "." + p.Process
 	case KindNode:
 		return "node." + p.Node
 	case KindController:
@@ -558,7 +576,7 @@ var BusSnapshotGrants = struct{ Publish []string }{Publish: []string{
 // a permission that cannot be derived from a declaration is a permission nobody can explain.
 func PermissionsFor(p Principal) (Permissions, error) {
 	for _, part := range []struct{ what, value string }{
-		{"node", p.Node}, {"module", p.Module},
+		{"node", p.Node}, {"module", p.Module}, {"process", p.Process},
 	} {
 		if part.value == "" {
 			continue
@@ -735,6 +753,12 @@ func PermissionsFor(p Principal) (Permissions, error) {
 			return Permissions{}, err
 		}
 
+	case KindProcess:
+		var err error
+		if pub, sub, err = processGrants(p); err != nil {
+			return Permissions{}, err
+		}
+
 	case KindPerson:
 		// Tools, and nothing else. Every subject a person may publish is a tool call; a person
 		// who could publish an event would be able to claim a module said something.
@@ -1128,6 +1152,13 @@ func PermissionsFor(p Principal) (Permissions, error) {
 		// for the same reason a person has none: nothing is delivered to it.
 		sub = append(sub, p.inbox())
 	}
+	if p.Kind == KindProcess {
+		// Its own reply space, and nothing wider (novox/hq ADR 0436 §1, §3): a process's queue consumer is
+		// pulled and acknowledged by publishing, granted above with its own stream and consumer name, never
+		// a generic EVENTS consumer's — consumerStream/consumerDurable below are a module's own, not a
+		// process's.
+		sub = append(sub, p.inbox())
+	}
 
 	if p.Kind == KindModule || p.Kind == KindNode || p.Kind == KindController {
 		// Its own reply space, and nothing wider.

internal/broker/process_grants.go

@@ -0,0 +1,52 @@
+package broker
+
+// The bus account of one process of a module that declares bus (novox/hq ADR 0436 §1, §2, §3, §5).
+//
+// **Never the module's own account's grants, never the tool runner's.** A process's authority is read
+// straight from its bus declaration — its emits, its queue's consumer, its state, whether it reads the
+// records of its module's own asks, and the tools and seat verbs it calls — and nothing else: it holds no
+// seat, serves no tool, hears no module stream, and answers nothing a caller asked (§3). Modelled on
+// provisionerGrants, the other kind of process account the mesh mints (ADR 0349 clauses 6 and 11).
+
+// processGrants is one process's whole authority: to publish, and to subscribe.
+func processGrants(p Principal) (pub, sub []string, err error) {
+	// 1. Its own events, under its module's own namespace — the same subjects the module's own principal
+	// would publish them on, had it declared them there instead (novox/hq ADR 0436 §1).
+	own := "mesh.mod." + p.Module
+	for _, e := range p.Emits {
+		pub = append(pub, own+".event."+e)
+	}
+
+	// 2. The one durable consumer of each work-queue stream its bus names (novox/hq ADR 0436 §1, §2, §6):
+	// asked about, pulled from and acknowledged, by the same name ConsumersOf composes the consumer under
+	// (QueueConsumer) — and no other stream's.
+	for _, q := range p.Queues {
+		consumer := p.Node + "_" + p.Module + "_" + q.Process
+		pub = append(pub,
+			"$JS.API.CONSUMER.INFO."+q.Stream+"."+consumer,
+			"$JS.API.CONSUMER.MSG.NEXT."+q.Stream+"."+consumer,
+			"$JS.ACK."+q.Stream+"."+consumer+".>")
+	}
+
+	// 3. Its module's own state, by the local names its bus names alone — never the whole of what the
+	// module keeps (novox/hq ADR 0436 §1), read and written as stateGrants gives any module's own bucket.
+	pub = append(pub, stateGrants(stateAccess{Module: p.Module, Node: p.Node, Keeps: p.State})...)
+
+	// 4. The router's records of its module's own asks (novox/hq ADR 0436 §1, ADR 0259 §3): the same
+	// direct-get subjects a module's own principal reads for the seats its Uses names that keep them —
+	// read here from the one list, so the two cannot disagree.
+	if p.Asks {
+		pub = append(pub, SeatTrafficOf(p.Module, nil, p.Uses, nil).Records...)
+	}
+
+	// 5. The tools and seat verbs it calls (novox/hq ADR 0152, ADR 0436 §1): the same derivation a
+	// module's own principal's invokes takes, so `callerNamed` (applied to every non-controller principal)
+	// adds the caller-named `call` variants for it exactly as it would for a module.
+	invoked, err := invokedSubjects(p.Invokes)
+	if err != nil {
+		return nil, nil, err
+	}
+	pub = append(pub, invoked...)
+
+	return pub, sub, nil
+}

internal/broker/process_grants_test.go

@@ -0,0 +1,234 @@
+package broker
+
+import (
+	"slices"
+	"sort"
+	"testing"
+)
+
+// A module's process with a bus declaration gets a bus account of its own (novox/hq ADR 0436 §1, §2, §3,
+// §5): named <machine>.<module>.<process id>, granted exactly its bus declaration and nothing of its
+// module's other grants or the tool runner's. The fixture is mesh-mail's future manifest shape (ADR 0436
+// §7, §8): process "send", stream "mail-sends" (MAIL_SENDS), state "sends", using operator-channel as the
+// router of its own asks (novox/hq ADR 0259 §3, seattraffic_test.go's operatorChannel()).
+
+// mailSenderProcess is the process principal PermissionsFor composes a bus account from, as
+// inventory.processesOf would read it off mesh-mail's manifest (1179/AC1's fixture, 1178's queue owner).
+func mailSenderProcess() Principal {
+	return Principal{Kind: KindProcess, Node: "novox", Module: "mesh-mail", Process: "send",
+		Emits:  []string{"mail.send.sent", "mail.send.failed"},
+		Queues: []QueueOwner{{Process: "send", Stream: "MAIL_SENDS", MaxDeliver: 5}},
+		State:  []string{"sends"}, Asks: true, Uses: []Seat{operatorChannel()},
+		Invokes: []string{"seat:operator-channel.tell"},
+	}
+}
+
+// 1180/AC1: the process principal publishes its emits, pulls and acknowledges its one queue consumer, reads
+// and writes its own state bucket, reads the router's records of its module's own asks, publishes its
+// invoked seat verb in its own name and the plain form, and subscribes only its own inbox.
+func TestAProcessIsGrantedExactlyItsBusDeclaration(t *testing.T) {
+	p := mailSenderProcess()
+	if got := p.Username(); got != "novox.mesh-mail.send" {
+		t.Fatalf("username: %q", got)
+	}
+	got := perms(t, p)
+	// review round 1, finding 8: the whole publish set, not merely that each wanted subject is somewhere in
+	// it — AC1 says "exactly". Dumped from a passing run (TestZZDumpProcessPublish, removed): 16 subjects,
+	// correct today.
+	wantPublish := []string{
+		"$JS.ACK.MAIL_SENDS.novox_mesh-mail_send.>",
+		"$JS.API.CONSUMER.CREATE.KV_mesh-mail_sends.>",
+		"$JS.API.CONSUMER.DELETE.KV_mesh-mail_sends.>",
+		"$JS.API.CONSUMER.INFO.MAIL_SENDS.novox_mesh-mail_send",
+		"$JS.API.CONSUMER.MSG.NEXT.MAIL_SENDS.novox_mesh-mail_send",
+		"$JS.API.DIRECT.GET.KV_mesh-mail_sends.>",
+		"$JS.API.DIRECT.GET.KV_messenger_asks.$KV.messenger_asks.mesh-mail.>",
+		"$JS.API.STREAM.INFO.KV_mesh-mail_sends",
+		"$JS.FC.KV_mesh-mail_sends.>",
+		"$KV.mesh-mail_sends.>",
+		"mesh.mod.mesh-mail.event.mail.send.failed",
+		"mesh.mod.mesh-mail.event.mail.send.sent",
+		"mesh.seat.operator-channel.call.tell.*.novox~mesh-mail~send",
+		"mesh.seat.operator-channel.call.tell.novox~mesh-mail~send",
+		"mesh.seat.operator-channel.tool.tell",
+		"mesh.seat.operator-channel.tool.tell.*",
+	}
+	pub := append([]string(nil), got.Publish...)
+	sort.Strings(pub)
+	want := append([]string(nil), wantPublish...)
+	sort.Strings(want)
+	if !slices.Equal(pub, want) {
+		t.Fatalf("the process's whole publish set:\n%v\nwant exactly:\n%v", pub, want)
+	}
+	if !allowed(got.Subscribe, "_INBOX.novox.mesh-mail.send.x") {
+		t.Error("the process does not hear its own inbox")
+	}
+	if len(got.Subscribe) != 1 {
+		t.Errorf("the process subscribes %v; want only its own inbox", got.Subscribe)
+	}
+}
+
+// 1180/AC3: a module with no bus process composes as main does, and adding one to mesh-mail changes
+// neither the tool runner's grants for a module it carries nor another module's own.
+func TestAddingAProcessLeavesOtherGrantsUnchanged(t *testing.T) {
+	plain := Principal{Kind: KindModule, Node: "novox", Module: "other", PasswordHash: "x"}
+	before := perms(t, plain)
+	users, err := Users(Records{Nodes: []string{"novox"}, Assigned: map[string][]Declared{"novox": {
+		{Module: "other"},
+		{Module: "mesh-mail", Processes: []ProcessPrincipal{{Process: "send",
+			Emits: []string{"mail.send.sent"}}}, NoAccount: true},
+	}}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	var sawProcess, sawOther bool
+	for _, u := range users {
+		if u.Kind == KindProcess && u.Module == "mesh-mail" {
+			sawProcess = true
+		}
+		if u.Module == "other" {
+			sawOther = true
+			if got := perms(t, u); !equalStringSlices(got.Publish, before.Publish) || !equalStringSlices(got.Subscribe, before.Subscribe) {
+				t.Errorf("another module's grants changed: %+v, want %+v", got, before)
+			}
+		}
+		if u.Kind == KindModule && u.Module == "mesh-mail" {
+			t.Error("mesh-mail has no own secret broker (NoAccount), and should have no module principal of its own")
+		}
+	}
+	if !sawProcess {
+		t.Fatal("the process account was not composed at all")
+	}
+	if !sawOther {
+		t.Fatal("the module with no process was not composed")
+	}
+}
+
+// 1180/AC3: a process account is never carried by the machine's tool runner, so adding one to a module the
+// runtime carries changes nothing of the runtime's own grants for that module.
+func TestAddingAProcessLeavesTheToolRunnersCarryingUnchanged(t *testing.T) {
+	assigned := func(processes []ProcessPrincipal) map[string][]Declared {
+		return map[string][]Declared{"novox": {
+			{Module: RuntimeModule},
+			{Module: "mesh-mail", Serves: []string{"status"}, Processes: processes},
+		}}
+	}
+	without, err := Users(Records{Nodes: []string{"novox"}, Assigned: assigned(nil)})
+	if err != nil {
+		t.Fatal(err)
+	}
+	with, err := Users(Records{Nodes: []string{"novox"}, Assigned: assigned([]ProcessPrincipal{
+		{Process: "send", Emits: []string{"mail.send.sent"}},
+	})})
+	if err != nil {
+		t.Fatal(err)
+	}
+	runtimeOf := func(users []Principal) Principal {
+		for _, u := range users {
+			if u.Kind == KindNodeTools {
+				return u
+			}
+		}
+		t.Fatal("the tool runner was not composed")
+		return Principal{}
+	}
+	before, after := perms(t, runtimeOf(without)), perms(t, runtimeOf(with))
+	if !equalStringSlices(before.Publish, after.Publish) || !equalStringSlices(before.Subscribe, after.Subscribe) {
+		t.Errorf("the tool runner's grants changed when mesh-mail gained a process: before %+v, after %+v",
+			before, after)
+	}
+}
+
+// 1180/AC2, the grant test of ADR 0436 clause 3: a process account answers no tool call or seat verb,
+// publishes no warrant, holds no seat (operator-channel included), and hears no restricted stream — however
+// wide its own grants (emits, its queue, its state, its asks and its invokes) are.
+func TestAProcessAccountAnswersNothing(t *testing.T) {
+	p := mailSenderProcess()
+	got := perms(t, p)
+	for _, s := range []string{
+		// Every shape a tool call or a seat verb is answered on: a module's own namespace, a seat's, and
+		// the caller-named `call` kind naming any caller — which calledSubscribe would add if a `tool`
+		// grant ever reached Subscribe.
+		"mesh.mod.mesh-mail.tool.send",
+		"mesh.mod.mesh-mail.tool.>",
+		"mesh.seat.operator-channel.tool.tell",
+		"mesh.seat.operator-channel.call.tell.*",
+		"mesh.seat.operator-channel.call.tell.mesh-controller",
+	} {
+		if allowed(got.Subscribe, s) {
+			t.Errorf("a process account may subscribe %s, and could answer a call or a verb", s)
+		}
+	}
+	// No warrant: only operator-channel's holder publishes the asker's decided event (ADR 0259 §3).
+	if allowed(got.Publish, "mesh.seat.operator-channel.event.decided.mesh-mail") {
+		t.Error("a process account may publish a warrant")
+	}
+	// No seat held: the holder-only subjects (its accept queue, its worker) are refused.
+	for _, s := range []string{
+		"mesh.seat.operator-channel.accept.ask.mesh-mail",
+		"$JS.API.CONSUMER.MSG.NEXT.SEAT_OPERATOR_CHANNEL.SEAT_OPERATOR_CHANNEL_worker",
+	} {
+		if allowed(got.Subscribe, s) || allowed(got.Publish, s) {
+			t.Errorf("a process account holds operator-channel: %s", s)
+		}
+	}
+	// No restricted stream: a process never hears a module stream at all (it has no Hears), restricted or
+	// not — the generic rule ADR 0376 §1 holds for it as it does for the tool runner.
+	if allowed(got.Subscribe, "mesh.stream.mesh-mail.event.mail.mesh.message.added") {
+		t.Error("a process account hears a module's stream")
+	}
+	if got.Subscribe == nil || len(got.Subscribe) != 1 {
+		t.Fatalf("a process account's whole subscribe list: %v; want only its own inbox", got.Subscribe)
+	}
+}
+
+// Every process account composed for a mesh is held to the same rule (ADR 0436 clause 3): checked across
+// the whole shape Users() composes, not only the one fixture above.
+func TestEveryComposedProcessAccountAnswersNothing(t *testing.T) {
+	users, err := Users(Records{Nodes: []string{"novox"}, Assigned: map[string][]Declared{"novox": {
+		{Module: "messenger", Holds: []Seat{operatorChannel()}, RunsAs: "messenger"},
+		{Module: "mesh-mail", RunsAs: "mesh-mail", Uses: []Seat{operatorChannel()},
+			Processes: []ProcessPrincipal{{Process: "send", Emits: []string{"mail.send.sent"},
+				Asks: true, Invokes: []string{"seat:operator-channel.tell"}}}},
+	}}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	checked := 0
+	for _, u := range users {
+		if u.Kind != KindProcess {
+			continue
+		}
+		checked++
+		got := perms(t, u)
+		for _, s := range []string{
+			"mesh.seat.operator-channel.call.tell.*",               // answers any caller
+			"mesh.seat.operator-channel.accept.ask." + u.Module,    // a caller's own submit, never a process's
+			"mesh.seat.operator-channel.event.decided." + u.Module, // the holder's warrant alone
+		} {
+			if allowed(got.Subscribe, s) || allowed(got.Publish, s) {
+				t.Errorf("%s may reach %s, which only a holder or an asking module's own principal may",
+					u.Username(), s)
+			}
+		}
+	}
+	if checked == 0 {
+		t.Fatal("no process account was composed to check")
+	}
+}
+
+func equalStringSlices(a, b []string) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	seen := map[string]bool{}
+	for _, x := range a {
+		seen[x] = true
+	}
+	for _, x := range b {
+		if !seen[x] {
+			return false
+		}
+	}
+	return true
+}

internal/broker/streams.go

@@ -65,11 +65,21 @@ type Stream struct {
 	// Restricted marks a module's stream restricted by a grant (novox/hq ADR 0363 §4), in the stream's own
 	// metadata, so whoever keeps one of its messages reads it from the bus (ADR 0376 §3).
 	Restricted bool
+	// WorkQueue marks a module stream declared retention: work-queue (novox/hq ADR 0436 §6), in the
+	// stream's own metadata, so a dead letter kept from it is read as drop-only from the bus, by the
+	// declaration and not by the bus's work-queue retention alone — which SEAT_* and other mesh-internal
+	// streams share without being one of ADR 0436's, and whose dead letters are still delivered again
+	// (ADR 0264 §4).
+	WorkQueue bool
 }
 
 // RestrictedMetadata is the key a restricted stream's metadata says it under.
 const RestrictedMetadata = "mesh-restricted"
 
+// WorkQueueMetadata is the key a module stream declared retention: work-queue (novox/hq ADR 0436 §6) says
+// it under: never set by a mesh-internal work-queue stream (a seat's, a check's), only by Stream.WorkQueue.
+const WorkQueueMetadata = "mesh-work-queue"
+
 // AssignmentsStream holds every assignment's membership, the newest per subject.
 const AssignmentsStream = "ASSIGNMENTS"
 

internal/broker/users.go

@@ -46,6 +46,9 @@ type Declared struct {
 	Logs []Log
 	// Streams are the streams it owns, each its events' one place (novox/hq ADR 0363).
 	Streams []ModuleStream
+	// Queues are its own work-queue streams and the one process each is the consumer of (novox/hq ADR 0436
+	// §1, §2, §6): one durable consumer per entry, named `<node>_<module>_<process id>`.
+	Queues []QueueOwner
 	// Hears are the module streams it hears on this machine, each with the subjects it was granted
 	// (novox/hq ADR 0363 §5); HearsAStream says its `consumes` names a module that owns a stream, granted
 	// or not, so its membership is issued again when a grant changes.
@@ -73,6 +76,31 @@ type Declared struct {
 	// declares the own secret ProvisionerSecret its account is delivered in (novox/hq ADR 0349 clause 11, design 57
 	// P3). The client is given a bus account of its own, never the module's or the tool runner's.
 	ProvisionsNode bool
+	// Processes are this module's own processes that declare bus (novox/hq ADR 0436 §1), each getting a
+	// principal of its own: granted exactly what its bus says, and nothing of this module's other grants —
+	// composed whether or not the module itself has an account (NoAccount), because a process account is
+	// delivered in its own secret, broker-<process id>, never the module's `broker`.
+	Processes []ProcessPrincipal
+}
+
+// ProcessPrincipal is one process of a module that declares bus (novox/hq ADR 0436 §1, §2), as the broker
+// composes its own account from: its own emits, its own work-queue consumers, its own state, whether it
+// reads the router's records of its module's own asks, and the tools and seat verbs it calls.
+type ProcessPrincipal struct {
+	// Process is the process resource's id, naming the account <node>.<module>.<process id>.
+	Process string
+	// Emits are the events this process may publish, named as the module's own Emits are.
+	Emits []string
+	// Queues are the module's own work-queue streams this process is the one consumer of.
+	Queues []QueueOwner
+	// State is the module's own state, by local name, this process reads and writes.
+	State []string
+	// Asks says whether this process reads the records of its module's own asks (novox/hq ADR 0259 §3), on
+	// whichever seats the module uses that keep them (the router's, operator-channel, among others).
+	Asks bool
+	// Invokes are the tools and seat verbs this process calls, each <module>.<tool> or a role's
+	// seat:<seat>.<verb>, or * for every tool on the mesh.
+	Invokes []string
 }
 
 // Records is what composing a user list needs to know about the mesh, and nothing more.
@@ -137,6 +165,17 @@ func Users(r Records) ([]Principal, error) {
 			}
 		}
 		for _, d := range r.Assigned[node] {
+			// **A process account is its own, delivered in its own secret** (broker-<process id>, novox/hq
+			// ADR 0436 §1, §2), never the module's `broker` — so it is composed whether or not the module
+			// itself has an account, and is never carried by the machine's runtime, which runs as the
+			// operator's account (ADR 0436 §5): added here, before either of those is judged.
+			for _, pr := range d.Processes {
+				out = append(out, Principal{
+					Kind: KindProcess, Node: node, Module: d.Module, Process: pr.Process,
+					Emits: pr.Emits, Queues: pr.Queues, State: pr.State, Uses: d.Uses, Asks: pr.Asks,
+					Invokes: pr.Invokes,
+				})
+			}
 			if runtimeHere && d.Module == RuntimeModule {
 				continue
 			}
@@ -155,7 +194,7 @@ func Users(r Records) ([]Principal, error) {
 				Holds: d.Holds, Uses: d.Uses, Watches: d.Watches, Invokes: d.Invokes,
 				State: stateNames(d.State), Reads: d.Reads, SnapshotsTheBus: d.SnapshotsTheBus,
 				PerMachine: perMachineNames(d.State), KeyedReads: d.KeyedReads,
-				Logs: logNames(d.Logs), Streams: d.Streams, Hears: ComposedHears(d),
+				Logs: logNames(d.Logs), Streams: d.Streams, Hears: ComposedHears(d), Queues: d.Queues,
 			})
 			// **The vault's holder asks the desks and the issuing providers itself** (issue 723), under the
 			// account its own runtime runs on (ADR 0259 §8's runs-as): the one module granted it.

internal/catalogue/declaration.go

@@ -680,7 +680,13 @@ func (r Resolution) compose(with Rendering, owner map[string]string,
 			if !ok || family == "" || with.Needed[m.Module][name] == "" {
 				continue
 			}
-			first = append(first, ownedBy(m.SecretsOwner, map[string]any{
+			// A per-secret owner (novox/hq ADR 0436 §1) stands in for the module's secrets-owner, when
+			// the manifest named one for this secret (or the family it belongs to).
+			owner := m.SecretsOwner
+			if own.Owner != "" {
+				owner = own.Owner
+			}
+			first = append(first, ownedBy(owner, map[string]any{
 				"id": NeedID(name), "type": "file", "path": own.Path, "sealed": with.Needed[m.Module][name],
 			}))
 		}
@@ -694,6 +700,9 @@ func (r Resolution) compose(with Rendering, owner map[string]string,
 				if m.Module == RuntimeModule && r.Account != "" {
 					owner = r.Account
 				}
+				if o := m.OwnSecrets[name].Owner; o != "" {
+					owner = o
+				}
 				first = append(first, ownedBy(owner, map[string]any{
 					"id": NeedID(name), "type": "file", "path": m.OwnSecrets[name].Path, HandedSecretField: name,
 				}))
@@ -709,6 +718,9 @@ func (r Resolution) compose(with Rendering, owner map[string]string,
 				if m.Module == RuntimeModule && r.Account != "" {
 					owner = r.Account
 				}
+				if o := m.OwnSecrets[name].Owner; o != "" {
+					owner = o
+				}
 				first = append(first, ownedBy(owner, map[string]any{
 					"id": NeedID(name), "type": "file", "path": m.OwnSecrets[name].Path, VaultSealedField: box,
 				}))
@@ -742,6 +754,9 @@ func (r Resolution) compose(with Rendering, owner map[string]string,
 			if m.Module == RuntimeModule && r.Account != "" {
 				owner = r.Account
 			}
+			if o := m.OwnSecrets[name].Owner; o != "" {
+				owner = o
+			}
 			first = append(first, ownedBy(owner, map[string]any{
 				"id": NeedID(name), "type": "file", "path": m.OwnSecrets[name].Path, "sealed": sealed,
 			}))
@@ -1169,6 +1184,10 @@ func (r Resolution) compose(with Rendering, owner map[string]string,
 			delete(copied, SecretsInEnvironment)
 			delete(copied, NamesOnPurpose)
 			delete(copied, TrustedField)
+			// A process's bus stays controller-side (novox/hq ADR 0436 §1): never composed onto the
+			// node-engine's process resource, whose wire declaration is mesh-host's own, vendored, with a
+			// strict decoder that refuses an unknown key.
+			delete(copied, ProcessBusField)
 			// **An operator's value, from the assignment** (novox/hq ADR 0112, ADR 0155): what a
 			// definition may not carry because it is true of one installation only. Filled from
 			// the same layers a mergeable file takes, and refused when no layer set it.

internal/catalogue/dir_into.go

@@ -168,7 +168,7 @@ func placedManifest(m Manifest, with Rendering) (Manifest, error) {
 			if err != nil {
 				return m, err
 			}
-			own[name] = OwnSecret{Path: filled, Taken: s.Taken, IssuedBy: s.IssuedBy}
+			own[name] = OwnSecret{Path: filled, Taken: s.Taken, IssuedBy: s.IssuedBy, Prompt: s.Prompt, Owner: s.Owner}
 		}
 		m.OwnSecrets = own
 	}

internal/catalogue/manifest.go

@@ -1953,6 +1953,7 @@ func parseManifest(raw []byte, predefined PredefinedList) (Manifest, error) {
 	problems = append(problems, LogProblems(m)...)
 	// And the streams it owns, and who may hear them (streams.go, novox/hq ADR 0363).
 	problems = append(problems, StreamProblems(m)...)
+	problems = append(problems, WorkQueueStreamProblems(m)...)
 	// And the defaults it gives its settings (setting_defaults.go, novox/hq ADR 0262), or, written in the
 	// config form, the whole declaration of each value (config.go, novox/hq ADR 0348).
 	if m.DeclaresConfig() {
@@ -1990,6 +1991,7 @@ func parseManifest(raw []byte, predefined PredefinedList) (Manifest, error) {
 	// facts about the catalogue and are checked at registration (CatalogueProblems).
 	problems = append(problems, declaredSeatProblems(m)...)
 	problems = append(problems, RunsAsProblems(m)...)
+	problems = append(problems, ProcessBusProblems(m)...)
 	problems = append(problems, ReadsHolderProblems(m)...)
 	problems = append(problems, FilesHolderProblems(m)...)
 	if m.Computed != "" && len(m.Resources) > 0 {
@@ -2348,6 +2350,7 @@ func parseManifest(raw []byte, predefined PredefinedList) (Manifest, error) {
 				m.Module, name, own.IssuedBy, IssuedOutside))
 		}
 		problems = append(problems, ownSecretPromptProblems(m, name, own.Prompt, IsFamily(name))...)
+		problems = append(problems, ownSecretOwnerProblems(m, name, own.Owner)...)
 	}
 	localOf := map[string]string{}
 	for _, to := range m.SecretRequirements() {
@@ -2854,12 +2857,7 @@ func replacesProblems(m Manifest) []string {
 func invokeProblems(m Manifest) []string {
 	var problems []string
 	for _, t := range m.Invokes {
-		if t == "*" {
-			continue
-		}
-		t = strings.TrimPrefix(t, "seat:")
-		module, tool, named := strings.Cut(t, ".")
-		if !named || !name.MatchString(module) || !toolName.MatchString(tool) {
+		if !invokeNameValid(t) {
 			problems = append(problems, fmt.Sprintf(
 				"%s invokes %q, which does not name a tool: a module invokes <module>.<tool>, or "+
 					"* for every tool on the mesh (novox/hq ADR 0152)", m.Module, t))
@@ -2930,6 +2928,11 @@ type OwnSecret struct {
 	// family's member suffix, filled where the secret is asked for. Optional; reviewed in the
 	// module's pull request like the rest of the manifest.
 	Prompt string
+	// Owner is the account this secret's files belong to on the machine, in place of the module's
+	// secrets-owner (novox/hq ADR 0436 §1): an account the module makes (a `user` resource of that
+	// name), never root and never the operator account. Empty means the module's secrets-owner, or
+	// root where that is absent too.
+	Owner string
 }
 
 // MeshMayMake says the mesh may put a value it makes in place of the one the secret holds: the
@@ -2984,6 +2987,34 @@ func ownSecretPromptProblems(m Manifest, name, prompt string, family bool) []str
 	return problems
 }
 
+// ownSecretOwnerProblems is what is wrong with an own secret's declared owner (novox/hq ADR 0436 §1): naming
+// an account the module makes — a `user` resource of that name — never root, which a secret file owned by it
+// would make readable by anything, and never the operator account's placeholder (`${machine:account}`), which
+// the mesh fills per machine and a manifest cannot say safely (novox/hq ADR 0436, settled by the lead).
+func ownSecretOwnerProblems(m Manifest, name, owner string) []string {
+	if owner == "" {
+		return nil
+	}
+	if owner == "root" {
+		return []string{fmt.Sprintf(
+			"%s names %q as the owner of its secret %q; an own secret's owner is an account the module "+
+				"makes, never root (novox/hq ADR 0436 §1)", m.Module, owner, name)}
+	}
+	if owner == "${machine:account}" {
+		return []string{fmt.Sprintf(
+			"%s names %q as the owner of its secret %q; an own secret's owner is an account the module "+
+				"makes, never the operator account (novox/hq ADR 0436 §1)", m.Module, owner, name)}
+	}
+	for _, r := range m.Resources {
+		if fmt.Sprint(r["type"]) == "user" && fmt.Sprint(r["name"]) == owner {
+			return nil
+		}
+	}
+	return []string{fmt.Sprintf(
+		"%s names %q as the owner of its secret %q, which it does not make: a user resource named %q "+
+			"(novox/hq ADR 0436 §1)", m.Module, owner, name, owner)}
+}
+
 // OwnSecrets is a module's own secrets by name. On the wire each is a path, or an object naming
 // the path and how it is taken; written back the way it was read, so a manifest the mesh holds
 // keeps its bytes.
@@ -3006,13 +3037,14 @@ func (o *OwnSecrets) UnmarshalJSON(raw []byte) error {
 			Taken    string `json:"taken,omitempty"`
 			IssuedBy string `json:"issued-by,omitempty"`
 			Prompt   string `json:"prompt,omitempty"`
+			Owner    string `json:"owner,omitempty"`
 		}
 		dec := json.NewDecoder(bytes.NewReader(body))
 		dec.DisallowUnknownFields()
 		if err := dec.Decode(&long); err != nil {
-			return fmt.Errorf("own-secrets.%s: a path, or {\"path\", \"taken\", \"issued-by\", \"prompt\"}: %w", name, typedUnknown(err))
+			return fmt.Errorf("own-secrets.%s: a path, or {\"path\", \"taken\", \"issued-by\", \"prompt\", \"owner\"}: %w", name, typedUnknown(err))
 		}
-		out[name] = OwnSecret{Path: long.Path, Taken: long.Taken, IssuedBy: long.IssuedBy, Prompt: long.Prompt}
+		out[name] = OwnSecret{Path: long.Path, Taken: long.Taken, IssuedBy: long.IssuedBy, Prompt: long.Prompt, Owner: long.Owner}
 	}
 	*o = out
 	return nil
@@ -3021,7 +3053,7 @@ func (o *OwnSecrets) UnmarshalJSON(raw []byte) error {
 func (o OwnSecrets) MarshalJSON() ([]byte, error) {
 	entries := make(map[string]any, len(o))
 	for name, s := range o {
-		if s.Taken == "" && s.IssuedBy == "" && s.Prompt == "" {
+		if s.Taken == "" && s.IssuedBy == "" && s.Prompt == "" && s.Owner == "" {
 			entries[name] = s.Path
 			continue
 		}
@@ -3035,6 +3067,9 @@ func (o OwnSecrets) MarshalJSON() ([]byte, error) {
 		if s.Prompt != "" {
 			long["prompt"] = s.Prompt
 		}
+		if s.Owner != "" {
+			long["owner"] = s.Owner
+		}
 		entries[name] = long
 	}
 	return json.Marshal(entries)
@@ -3074,7 +3109,7 @@ func (o OwnSecrets) Lookup(name string) (s OwnSecret, family string, ok bool) {
 		}
 		if family == "" || len(declared) > len(family) {
 			s, family, ok = OwnSecret{Path: strings.Replace(f.Path, "*", rest, 1), Taken: f.Taken, IssuedBy: f.IssuedBy,
-				Prompt: f.Prompt}, declared, true
+				Prompt: f.Prompt, Owner: f.Owner}, declared, true
 		}
 	}
 	return s, family, ok

internal/catalogue/own_secret_owner_test.go

@@ -0,0 +1,116 @@
+package catalogue
+
+import (
+	"strings"
+	"testing"
+)
+
+// An own secret (or a family) may declare `owner` (novox/hq ADR 0436 §1): the account the files holding it
+// belong to on the machine, when that account is not the module's secrets-owner default. The fixture is
+// mesh-mail's future manifest shape (ADR 0436 §7): a process account `mesh-mail-send` the module makes, and its
+// own-secret family `mail-credential-*` owned by it.
+
+// mailSenderManifest is the fixture every mail-sender issue builds on: the real parts of mesh-mail's manifest
+// taken from mesh-catalog/modules/mesh-mail/module.json, extended as ADR 0436 §7-§8 describe, with `own` naming
+// the account that owns the family's files.
+func mailSenderManifest(t *testing.T, own string) Manifest {
+	t.Helper()
+	ownSecrets := `"mail-credential-*":{"path":"/var/lib/mesh-mail/mail-credential-*.secret","issued-by":"outside"`
+	if own != "" {
+		ownSecrets += `,"owner":"` + own + `"`
+	}
+	ownSecrets += `}`
+	m, err := ParseManifest([]byte(`{"module":"mesh-mail","version":"1","secrets-owner":"mesh-mail","own-secrets":{` +
+		ownSecrets + `},"resources":[{"id":"account","type":"user","name":"mesh-mail-send"}]}`))
+	if err != nil {
+		t.Fatalf("a manifest with own=%q was refused: %v", own, err)
+	}
+	return m
+}
+
+// 1170/AC1: a family owned by the module's own account lands at 0600, owned by that account — and a module's
+// other own secrets (no per-secret owner declared) keep secrets-owner, unchanged.
+func TestAnOwnSecretsOwnerIsGivenToItsFiles(t *testing.T) {
+	m := mailSenderManifest(t, "mesh-mail-send")
+	m.OwnSecrets["smtp-relay-key"] = OwnSecret{Path: "/var/lib/mesh-mail/smtp-relay-key", Taken: TakenAtStart}
+	r := Resolution{Node: "novox", Modules: []Manifest{m}}
+	out, err := r.Declaration(Rendering{
+		Needed: map[string]map[string]string{"mesh-mail": {"mail-credential-smtp": "sealed-credential", "smtp-relay-key": "sealed-relay"}},
+	})
+	if err != nil {
+		t.Fatalf("composing the declaration: %v", err)
+	}
+	var family, plain map[string]any
+	for _, res := range out {
+		if res["type"] != "file" {
+			continue
+		}
+		switch res["path"] {
+		case "/var/lib/mesh-mail/mail-credential-smtp.secret":
+			family = res
+		case "/var/lib/mesh-mail/smtp-relay-key":
+			plain = res
+		}
+	}
+	if family == nil {
+		t.Fatalf("the family member was not composed at all: %v", out)
+	}
+	if got := family["owner"]; got != "mesh-mail-send" {
+		t.Fatalf("the family member's owner: %v; want mesh-mail-send", got)
+	}
+	// review round 1, finding 7: asserted, not merely logged. ownedBy never sets "mode", so a sealed secret
+	// file carries none here either — the host applies 0600 to every one regardless (novox/hq ADR 0086) —
+	// and the owner clause must not have added one of its own that could override that.
+	if _, has := family["mode"]; has {
+		t.Fatalf("the family member carries its own mode %v; the owner clause must not set one, so the "+
+			"host's 0600 for every sealed secret file stands", family["mode"])
+	}
+	if plain == nil {
+		t.Fatalf("the module's other own secret was not composed at all: %v", out)
+	}
+	if got := plain["owner"]; got != "mesh-mail" {
+		t.Fatalf("a secret with no per-secret owner kept %v; want the module's secrets-owner %q", got, "mesh-mail")
+	}
+}
+
+// 1170/AC2: an owner naming an account the module does not make, root, or the operator account's placeholder is
+// refused, naming the secret and the account.
+func TestAnOwnSecretsOwnerIsRefusedWhenItIsNotAnAccountTheModuleMakes(t *testing.T) {
+	for name, c := range map[string]struct{ owner, says string }{
+		"root":                    {"root", "root"},
+		"the operator account":    {"${machine:account}", "operator account"},
+		"an account not declared": {"not-made", "not-made"},
+	} {
+		_, err := ParseManifest([]byte(`{"module":"mesh-mail","version":"1","own-secrets":{` +
+			`"mail-credential-*":{"path":"/var/lib/mesh-mail/mail-credential-*.secret","issued-by":"outside","owner":"` +
+			c.owner + `"}},"resources":[{"id":"account","type":"user","name":"mesh-mail-send"}]}`))
+		if err == nil || !strings.Contains(err.Error(), "mail-credential-*") || !strings.Contains(err.Error(), c.says) {
+			t.Errorf("%s: %v; want a refusal naming the secret and %q", name, err, c.says)
+		}
+	}
+}
+
+// 1170/AC3: a manifest with no owner on any own secret composes exactly as it did before this clause existed:
+// every secret file belongs to the module's secrets-owner (or nothing, when that is absent too).
+func TestNoOwnerOnAnySecretComposesAsMainDoes(t *testing.T) {
+	m := mailSenderManifest(t, "")
+	r := Resolution{Node: "novox", Modules: []Manifest{m}}
+	out, err := r.Declaration(Rendering{
+		Needed: map[string]map[string]string{"mesh-mail": {"mail-credential-smtp": "sealed-credential"}},
+	})
+	if err != nil {
+		t.Fatalf("composing the declaration: %v", err)
+	}
+	var found bool
+	for _, res := range out {
+		if res["type"] == "file" && res["path"] == "/var/lib/mesh-mail/mail-credential-smtp.secret" {
+			found = true
+			if got := res["owner"]; got != "mesh-mail" {
+				t.Fatalf("with no per-secret owner declared, the file's owner: %v; want secrets-owner %q", got, "mesh-mail")
+			}
+		}
+	}
+	if !found {
+		t.Fatalf("the family member was not composed at all: %v", out)
+	}
+}

internal/catalogue/process_bus.go

@@ -0,0 +1,189 @@
+package catalogue
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
+// ProcessBusField is the key a process resource declares its bus on. Controller-side only: never composed
+// onto the node-engine's process resource (novox/hq ADR 0436 §1) — the wire declaration is mesh-host's own,
+// vendored, with a strict decoder that refuses an unknown key.
+const ProcessBusField = "bus"
+
+// ProcessBus is what one process of a module does on the bus (novox/hq ADR 0436 §1, §2, §3, §5): its own bus
+// account, granted exactly this and nothing of the module's other grants or the tool runner's — never a seat
+// to hold or serve, never a tool call or seat verb answered, never a restricted stream heard, never a
+// warrant published (§3, §5).
+type ProcessBus struct {
+	// Emits are the events this process emits, named locally, as the module's own Emits names them
+	// (EmitsAll): a process emits only what its module may emit as a whole.
+	Emits []string `json:"emits,omitempty"`
+	// Queues are the module's own work-queue streams (ADR 0436 §6) this process consumes.
+	Queues []string `json:"queues,omitempty"`
+	// State is the module's own state, by local name, this process reads and writes.
+	State []string `json:"state,omitempty"`
+	// Asks says whether this process reads the router's records of this module's own asks.
+	Asks bool `json:"asks,omitempty"`
+	// Invokes are the tools and seat verbs this process calls, each <module>.<tool> or a role's
+	// seat:<seat>.<verb> (as Manifest.Invokes), or * for every tool on the mesh.
+	Invokes []string `json:"invokes,omitempty"`
+}
+
+// UnmarshalJSON reads a process's bus strictly: an unknown key — serves, a seat to hold or claim, or
+// anything else that would answer a tool call or a seat's verb — is refused here, by name (novox/hq ADR
+// 0436 §3).
+func (b *ProcessBus) UnmarshalJSON(raw []byte) error {
+	type plain ProcessBus
+	var p plain
+	dec := json.NewDecoder(bytes.NewReader(raw))
+	dec.DisallowUnknownFields()
+	if err := dec.Decode(&p); err != nil {
+		return fmt.Errorf("a process's bus is {emits, queues, state, asks, invokes}: %w", typedUnknown(err))
+	}
+	*b = ProcessBus(p)
+	return nil
+}
+
+// processBusOf is the bus a process resource declares, and whether it declared one at all.
+func processBusOf(r map[string]any) (bus ProcessBus, present bool, err error) {
+	raw, present := r["bus"]
+	if !present {
+		return ProcessBus{}, false, nil
+	}
+	body, err := json.Marshal(raw)
+	if err != nil {
+		return ProcessBus{}, true, err
+	}
+	if err := json.Unmarshal(body, &bus); err != nil {
+		return ProcessBus{}, true, err
+	}
+	return bus, true, nil
+}
+
+// ProcessBuses is every process of this module that declares bus, by its id (the manifest's own resource
+// id, novox/hq ADR 0436, settled by the lead) — what the grant composition reads to grant a process
+// account exactly what it emits, consumes and calls (novox/hq ADR 0436 §2).
+func (m Manifest) ProcessBuses() map[string]ProcessBus {
+	var out map[string]ProcessBus
+	for _, r := range m.Resources {
+		if fmt.Sprint(r["type"]) != "process" {
+			continue
+		}
+		b, present, err := processBusOf(r)
+		if !present || err != nil {
+			continue
+		}
+		if out == nil {
+			out = map[string]ProcessBus{}
+		}
+		out[fmt.Sprint(r["id"])] = b
+	}
+	return out
+}
+
+// ProcessBusProblems is what is wrong with a manifest's processes' bus declarations (novox/hq ADR 0436 §1,
+// §3): the account rule is modelled on RunsAsProblems (seats_declared.go:522-550), and an invoked tool or
+// seat verb's shape on invokeProblems.
+func ProcessBusProblems(m Manifest) []string {
+	var problems []string
+	streams := map[string]bool{}
+	for _, s := range m.Streams {
+		streams[s.Name] = true
+	}
+	state := map[string]bool{}
+	for _, s := range m.State {
+		state[s.Name] = true
+	}
+	emits := map[string]bool{}
+	for _, e := range m.EmitsAll() {
+		emits[e] = true
+	}
+	for _, r := range m.Resources {
+		if fmt.Sprint(r["type"]) != "process" {
+			continue
+		}
+		id := fmt.Sprint(r["id"])
+		if _, present := r["bus"]; !present {
+			continue
+		}
+		b, _, err := processBusOf(r)
+		if err != nil {
+			problems = append(problems, fmt.Sprintf("%s's process %s declares bus: %v", m.Module, id, err))
+			continue
+		}
+		user, _ := r["user"].(string)
+		problems = append(problems, processAccountProblems(m, id, user)...)
+		for _, e := range b.Emits {
+			if !emits[e] {
+				problems = append(problems, fmt.Sprintf(
+					"%s's process %s's bus emits %q, which %s does not declare as its own (novox/hq ADR 0436 §1)",
+					m.Module, id, e, m.Module))
+			}
+		}
+		for _, q := range b.Queues {
+			if !streams[q] {
+				problems = append(problems, fmt.Sprintf(
+					"%s's process %s's bus queues %q, which %s does not declare as its own stream (novox/hq "+
+						"ADR 0436 §1)", m.Module, id, q, m.Module))
+			}
+		}
+		for _, s := range b.State {
+			if !state[s] {
+				problems = append(problems, fmt.Sprintf(
+					"%s's process %s's bus reads and writes state %q, which %s does not declare as its own "+
+						"(novox/hq ADR 0436 §1)", m.Module, id, s, m.Module))
+			}
+		}
+		for _, t := range b.Invokes {
+			if !invokeNameValid(t) {
+				problems = append(problems, fmt.Sprintf(
+					"%s's process %s's bus invokes %q, which does not name a tool: a process invokes "+
+						"<module>.<tool>, or a role's seat:<seat>.<verb> (novox/hq ADR 0436 §1)", m.Module, id, t))
+			}
+		}
+	}
+	return problems
+}
+
+// processAccountProblems is what is wrong with one process's bus account (novox/hq ADR 0436 §1, §2): an
+// account the module makes — a `user` resource of that name — never root and never the operator account,
+// which a manifest cannot say safely (a node with no account has nothing to resolve it to, novox/hq ADR
+// 0436, settled by the lead).
+func processAccountProblems(m Manifest, processID, user string) []string {
+	switch {
+	case user == "":
+		return []string{fmt.Sprintf(
+			"%s's process %s declares bus and names no account; a process account is a user resource the "+
+				"module makes, never root and never the operator account (novox/hq ADR 0436 §1, §2)",
+			m.Module, processID)}
+	case user == "root":
+		return []string{fmt.Sprintf(
+			"%s's process %s runs as root; a process account is the module's own, never root (novox/hq ADR "+
+				"0436 §1, §2)", m.Module, processID)}
+	case user == "${machine:account}":
+		return []string{fmt.Sprintf(
+			"%s's process %s runs as the operator account; a process account is the module's own, never the "+
+				"operator's (novox/hq ADR 0436 §1, §2)", m.Module, processID)}
+	}
+	for _, r := range m.Resources {
+		if fmt.Sprint(r["type"]) == "user" && fmt.Sprint(r["name"]) == user {
+			return nil
+		}
+	}
+	return []string{fmt.Sprintf(
+		"%s's process %s runs as %s, which it does not make: a user resource named %s (novox/hq ADR 0436 §1, "+
+			"§2)", m.Module, processID, user, user)}
+}
+
+// invokeNameValid says a module or process's invoked entry names a tool: <module>.<tool>, a role's
+// seat:<seat>.<verb>, or * for every tool on the mesh (novox/hq ADR 0152, ADR 0436 §1).
+func invokeNameValid(t string) bool {
+	if t == "*" {
+		return true
+	}
+	t = strings.TrimPrefix(t, "seat:")
+	first, second, named := strings.Cut(t, ".")
+	return named && name.MatchString(first) && toolName.MatchString(second)
+}

internal/catalogue/process_bus_test.go

@@ -0,0 +1,191 @@
+package catalogue
+
+import (
+	"strings"
+	"testing"
+)
+
+// A process resource may declare `bus` (novox/hq ADR 0436 §1): what it emits, the module's own work-queue
+// streams it consumes, the module's own state it reads and writes, whether it reads the router's records of
+// this module's own asks, and the tools and seat verbs it calls. The fixture is mesh-mail's future manifest
+// shape (ADR 0436 §7, §8), copied from mesh-catalog/modules/mesh-mail/module.json and extended as settled by
+// the lead: process id "send" is the manifest's own `id` (internal/catalogue/runtime.go:72-74 is the model for
+// a process id); the account file uses the controller's real JSON tags (modules.go:1041-1056 issueWith).
+func mailSenderProcessManifest(t *testing.T, bus string) string {
+	t.Helper()
+	process := `{"id":"send","type":"process","run":["./mesh-mail","send"],"user":"mesh-mail-send"`
+	if bus != "" {
+		process += `,"bus":` + bus
+	}
+	process += `}`
+	// The stream itself is plain here, not retention work-queue: 1179 checks only that a process names a
+	// stream the module owns, never its retention — that rule is 1178's (WorkQueueStreamProblems), and is
+	// tested against its own fixture there (work_queue_consumer_test.go) so this one stays accepted whether
+	// or not a process currently names "mail-sends" in bus.queues.
+	return `{"module":"mesh-mail","version":"1","emits":["mail.send.sent","mail.send.failed"],` +
+		`"state":["sends"],"streams":[{"name":"mail-sends","events":["mail.send.approved"],"max-age-days":1,` +
+		`"max-mib":64}],"resources":[{"id":"account","type":"user","name":"mesh-mail-send"},` + process + `]}`
+}
+
+const mailSenderBus = `{"emits":["mail.send.sent","mail.send.failed"],"queues":["mail-sends"],` +
+	`"state":["sends"],"asks":true,"invokes":["seat:operator-channel.tell"]}`
+
+// 1179/AC1: a well-formed bus on a process whose account the module makes is accepted, and the catalogue
+// gives it whole to the grant composition (ProcessBuses, which 1180 reads).
+func TestAProcessDeclaresItsBusAndIsAccepted(t *testing.T) {
+	m, err := ParseManifest([]byte(mailSenderProcessManifest(t, mailSenderBus)))
+	if err != nil {
+		t.Fatalf("a well-formed process bus was refused: %v", err)
+	}
+	buses := m.ProcessBuses()
+	b, ok := buses["send"]
+	if !ok {
+		t.Fatalf("the process's bus was not given to the grant composition: %+v", buses)
+	}
+	if !strSliceEqual(b.Emits, []string{"mail.send.sent", "mail.send.failed"}) ||
+		!strSliceEqual(b.Queues, []string{"mail-sends"}) || !strSliceEqual(b.State, []string{"sends"}) ||
+		!b.Asks || !strSliceEqual(b.Invokes, []string{"seat:operator-channel.tell"}) {
+		t.Fatalf("the bus read as %+v", b)
+	}
+}
+
+func strSliceEqual(a, b []string) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i := range a {
+		if a[i] != b[i] {
+			return false
+		}
+	}
+	return true
+}
+
+// 1179/AC2: a bus on a process with no user, user root, or the operator account is refused naming the
+// process and the account rule.
+func TestAProcessBusAccountMustBeTheModulesOwn(t *testing.T) {
+	for name, c := range map[string]struct{ user, says string }{
+		"no user":              {"", "send"},
+		"user root":            {"root", "root"},
+		"the operator account": {"${machine:account}", "operator"},
+	} {
+		raw := `{"module":"mesh-mail","version":"1","emits":["mail.send.sent"],"state":["sends"],` +
+			`"streams":[{"name":"mail-sends","events":["mail.send.approved"],"retention":"work-queue",` +
+			`"max-deliveries":5}],"resources":[{"id":"account","type":"user","name":"mesh-mail-send"},` +
+			`{"id":"send","type":"process","run":["./mesh-mail","send"]`
+		if c.user != "" {
+			raw += `,"user":"` + c.user + `"`
+		}
+		raw += `,"bus":{"emits":["mail.send.sent"]}}]}`
+		_, err := ParseManifest([]byte(raw))
+		if err == nil || !strings.Contains(err.Error(), "send") || !strings.Contains(err.Error(), c.says) {
+			t.Errorf("%s: %v; want a refusal naming the process and %q", name, err, c.says)
+		}
+	}
+}
+
+// 1179/AC3: a bus naming a stream, state or event the module does not declare as its own is refused naming
+// it.
+func TestAProcessBusNamesOnlyTheModulesOwn(t *testing.T) {
+	for name, c := range map[string]struct{ bus, says string }{
+		"another module's event": {`{"emits":["billing.paid"]}`, "billing.paid"},
+		"another module's queue": {`{"queues":["other-queue"]}`, "other-queue"},
+		"another module's state": {`{"state":["other-state"]}`, "other-state"},
+	} {
+		_, err := ParseManifest([]byte(mailSenderProcessManifest(t, c.bus)))
+		if err == nil || !strings.Contains(err.Error(), c.says) {
+			t.Errorf("%s: %v; want a refusal naming %q", name, err, c.says)
+		}
+	}
+}
+
+// 1179/AC4: a bus declaring serves, holds, claims or a seat is refused naming the key; a bus with invokes of
+// a tool or a seat verb is accepted.
+func TestAProcessBusNeverServesOrHoldsASeat(t *testing.T) {
+	for name, c := range map[string]struct{ bus, says string }{
+		"serves": {`{"emits":["mail.send.sent"],"serves":["send"]}`, "serves"},
+		"holds":  {`{"emits":["mail.send.sent"],"holds":["mail-sender"]}`, "holds"},
+		"claims": {`{"emits":["mail.send.sent"],"claims":["mail-sender"]}`, "claims"},
+		"seat":   {`{"emits":["mail.send.sent"],"seat":"mail-sender"}`, "seat"},
+	} {
+		_, err := ParseManifest([]byte(mailSenderProcessManifest(t, c.bus)))
+		if err == nil || !strings.Contains(err.Error(), c.says) {
+			t.Errorf("%s: %v; want a refusal naming %q", name, err, c.says)
+		}
+	}
+	accepted := `{"emits":["mail.send.sent","mail.send.failed"],"invokes":["seat:operator-channel.tell","mail.status"]}`
+	if _, err := ParseManifest([]byte(mailSenderProcessManifest(t, accepted))); err != nil {
+		t.Fatalf("a bus invoking a tool and a seat verb was refused: %v", err)
+	}
+}
+
+// 1179/AC5: a process declaring bus is composed with no bus key on the wire, and is otherwise byte for byte
+// what main composes for the same process without bus.
+func TestAProcessesBusNeverReachesTheWire(t *testing.T) {
+	withBus, err := ParseManifest([]byte(mailSenderProcessManifest(t, mailSenderBus)))
+	if err != nil {
+		t.Fatal(err)
+	}
+	withoutBus, err := ParseManifest([]byte(mailSenderProcessManifest(t, "")))
+	if err != nil {
+		t.Fatal(err)
+	}
+	with := Rendering{Needed: map[string]map[string]string{}}
+	outWith, err := Resolution{Node: "novox", Modules: []Manifest{withBus}}.Declaration(with)
+	if err != nil {
+		t.Fatalf("composing with bus: %v", err)
+	}
+	outWithout, err := Resolution{Node: "novox", Modules: []Manifest{withoutBus}}.Declaration(with)
+	if err != nil {
+		t.Fatalf("composing without bus: %v", err)
+	}
+	var withProcess, withoutProcess map[string]any
+	for _, r := range outWith {
+		if r["id"] == "mesh-mail.send" {
+			withProcess = r
+		}
+	}
+	for _, r := range outWithout {
+		if r["id"] == "mesh-mail.send" {
+			withoutProcess = r
+		}
+	}
+	if withProcess == nil || withoutProcess == nil {
+		t.Fatalf("the process was not composed at all: with=%v without=%v", withProcess, withoutProcess)
+	}
+	if _, has := withProcess["bus"]; has {
+		t.Fatalf("the process resource carried a bus key onto the wire: %v", withProcess)
+	}
+	delete(withProcess, "bus")
+	if !mapsEqual(withProcess, withoutProcess) {
+		t.Fatalf("with bus declared, the process composed differently: %+v\nwant: %+v", withProcess, withoutProcess)
+	}
+}
+
+func mapsEqual(a, b map[string]any) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for k, v := range a {
+		bv, ok := b[k]
+		if !ok {
+			return false
+		}
+		if av, ok := v.([]any); ok {
+			bbv, ok := bv.([]any)
+			if !ok || len(av) != len(bbv) {
+				return false
+			}
+			for i := range av {
+				if av[i] != bbv[i] {
+					return false
+				}
+			}
+			continue
+		}
+		if v != bv {
+			return false
+		}
+	}
+	return true
+}

internal/catalogue/seats_declared.go

@@ -280,6 +280,8 @@ func CatalogueProblems(shelf Shelf) []string {
 	problems = append(problems, StreamNameProblems(shelf)...)
 	// A module that hears a restricted stream runs as an account of its own (novox/hq ADR 0376 §2).
 	problems = append(problems, RestrictedHearingProblems(shelf)...)
+	// A work-queue stream is never asked for by another module's consumes (novox/hq ADR 0436 §6).
+	problems = append(problems, WorkQueueConsumedElsewhereProblems(shelf)...)
 
 	// Who declares what, and who declared it first.
 	declaredBy := map[string]string{}

internal/catalogue/stream_work_queue_test.go

@@ -0,0 +1,71 @@
+package catalogue
+
+import (
+	"strings"
+	"testing"
+)
+
+// A module stream may declare retention: work-queue (novox/hq ADR 0436 §6): a message is removed once a
+// consumer acknowledges it, the bus refusing a new one rather than dropping what it holds. The fixture is
+// mesh-mail's future `mail-sends` stream (ADR 0436 §7, §8), copied from the module.json shape at
+// /home/jochen/projects/novox/mesh-catalog/modules/mesh-mail/module.json and extended with retention,
+// max-deliveries and duplicates as the ADR's clause 6 describes.
+const mailSendsStream = `[{"name":"mail-sends","events":["mail.send.approved"],"max-age-days":1,"max-mib":64,` +
+	`"retention":"work-queue","max-deliveries":5,"duplicates":24}]`
+
+// 1177/AC1: a well-formed work-queue stream is accepted and read back whole. Named by one process in
+// bus.queues (novox/hq ADR 0436 §6, checked by 1178's WorkQueueStreamProblems), so this stays accepted once
+// that rule exists.
+func TestAWorkQueueStreamIsDeclaredAndAccepted(t *testing.T) {
+	m, err := ParseManifest([]byte(`{"module":"mesh-mail","version":"1","streams":` + mailSendsStream +
+		`,"resources":[{"id":"account","type":"user","name":"mesh-mail-send"},` +
+		`{"id":"send","type":"process","run":["./mesh-mail","send"],"user":"mesh-mail-send",` +
+		`"bus":{"queues":["mail-sends"]}}]}`))
+	if err != nil {
+		t.Fatalf("a well-formed work-queue stream was refused: %v", err)
+	}
+	s := m.Streams[0]
+	if s.Retention != StreamRetentionWorkQueue || s.MaxDeliveries != 5 || s.Duplicates != 24 ||
+		s.Days() != 1 || s.Cap() != 64 {
+		t.Fatalf("the stream read as %+v", s)
+	}
+}
+
+// 1177/AC2: a stream whose work-queue values are out of range, contradictory, or carries a grant is refused
+// naming the stream and the rule.
+func TestAWorkQueueStreamsValuesAreBounded(t *testing.T) {
+	for name, c := range map[string]struct{ streams, says string }{
+		"max-deliveries 0": {`[{"name":"mail-sends","events":["mail.send.approved"],"retention":"work-queue",` +
+			`"max-deliveries":0,"duplicates":24}]`, "between 1 and 10"},
+		"max-deliveries 11": {`[{"name":"mail-sends","events":["mail.send.approved"],"retention":"work-queue",` +
+			`"max-deliveries":11,"duplicates":24}]`, "between 1 and 10"},
+		"duplicates longer than its maximum age": {`[{"name":"mail-sends","events":["mail.send.approved"],` +
+			`"max-age-days":1,"retention":"work-queue","max-deliveries":5,"duplicates":25}]`, "longer than its maximum age"},
+		"an unknown retention": {`[{"name":"mail-sends","events":["mail.send.approved"],"retention":"sometimes"}]`,
+			"retention"},
+		"max-deliveries without retention work-queue": {`[{"name":"mail-sends","events":["mail.send.approved"],` +
+			`"max-deliveries":5}]`, "without retention"},
+		"duplicates without retention work-queue": {`[{"name":"mail-sends","events":["mail.send.approved"],` +
+			`"duplicates":24}]`, "without retention"},
+		"a work-queue stream carrying a grant": {`[{"name":"mail-sends","events":["mail.send.approved"],` +
+			`"retention":"work-queue","max-deliveries":5,` +
+			`"grant":{"config":"grants","events":"mail-sends.{key}.**"}}]`, "carrying a grant"},
+	} {
+		_, err := ParseManifest([]byte(mailManifest(t, c.streams, "")))
+		if err == nil || !strings.Contains(err.Error(), "mail-sends") || !strings.Contains(err.Error(), c.says) {
+			t.Errorf("%s: %v; want a refusal naming the stream and %q", name, err, c.says)
+		}
+	}
+}
+
+// 1177/AC3: a stream with no retention composes as main does — limits retention, dropping its oldest — proven
+// at the broker, where the bus's retention policy is decided (internal/broker/modstreams_test.go).
+func TestAStreamWithNoRetentionReadsAsLimits(t *testing.T) {
+	m, err := ParseManifest([]byte(mailManifest(t, mailStream, "")))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got := m.Streams[0].Retention; got != "" {
+		t.Fatalf("a stream declaring no retention read %q", got)
+	}
+}

internal/catalogue/streams.go

@@ -30,6 +30,18 @@ const (
 // GrantKey is the name in a grant's pattern that each key of the config value fills.
 const GrantKey = "{key}"
 
+// StreamRetentionWorkQueue is a stream's declared retention (novox/hq ADR 0436 §6): a message is removed
+// once a consumer acknowledges it, and the bus refuses a new one rather than dropping what it holds. Empty
+// is the mesh's own limits retention — kept until it ages or the stream fills, dropping its oldest.
+const StreamRetentionWorkQueue = "work-queue"
+
+// StreamLeastDeliveries and StreamMostDeliveries bound a work-queue stream's max-deliveries (novox/hq ADR
+// 0436 §6): how many times a message is handed over before it is given up as a dead letter.
+const (
+	StreamLeastDeliveries = 1
+	StreamMostDeliveries  = 10
+)
+
 // ReservedStreamPrefixes are the starts of the stream names the mesh derives, which no module's stream
 // may take: a seat's work queue, a log, a bucket, an object store, and the dead letters.
 var ReservedStreamPrefixes = []string{"SEAT_", "LOG_", "KV_", "OBJ_", "DEAD_"}
@@ -48,6 +60,15 @@ type StreamDeclaration struct {
 	MaxMiB     int `json:"max-mib,omitempty"`
 	// Grant restricts it, when said.
 	Grant *StreamGrant `json:"grant,omitempty"`
+	// Retention is how the stream decides what to keep when it fills (novox/hq ADR 0436 §6): empty for the
+	// mesh's own limits retention (dropping its oldest), or StreamRetentionWorkQueue.
+	Retention string `json:"retention,omitempty"`
+	// MaxDeliveries bounds how many times a work-queue message is handed over, 1 to 10; refused without
+	// retention work-queue (novox/hq ADR 0436 §6).
+	MaxDeliveries int `json:"max-deliveries,omitempty"`
+	// Duplicates is a work-queue stream's duplicate window in hours, at most its maximum age; refused
+	// without retention work-queue (novox/hq ADR 0436 §6).
+	Duplicates int `json:"duplicates,omitempty"`
 }
 
 // StreamGrant says which trusted config value of the module grants a consumer a part of the stream, and
@@ -67,7 +88,8 @@ func (s *StreamDeclaration) UnmarshalJSON(raw []byte) error {
 	dec := json.NewDecoder(bytes.NewReader(raw))
 	dec.DisallowUnknownFields()
 	if err := dec.Decode(&p); err != nil {
-		return fmt.Errorf("a stream is {name, events, max-age-days, max-mib, grant}: %w", typedUnknown(err))
+		return fmt.Errorf("a stream is {name, events, max-age-days, max-mib, grant, retention, max-deliveries, "+
+			"duplicates}: %w", typedUnknown(err))
 	}
 	*s = StreamDeclaration(p)
 	return nil
@@ -163,6 +185,44 @@ func StreamProblems(m Manifest) []string {
 			problems = append(problems, fmt.Sprintf("%s caps stream %q at %d MiB; a stream holds between %d and %d "+
 				"(novox/hq ADR 0363)", m.Module, s.Name, s.MaxMiB, StreamLeastMiB, StreamMostMiB))
 		}
+		// A stream may declare retention: work-queue (novox/hq ADR 0436 §6): a message removed once a
+		// consumer acknowledges it, the bus refusing a new one when full rather than dropping its oldest, with
+		// max-deliveries (1 to 10) and a duplicate window (duplicates, hours, at most its maximum age) -- both
+		// meaningless, and refused, without it. A work-queue stream is read by its one consumer, never granted.
+		switch s.Retention {
+		case "", StreamRetentionWorkQueue:
+		default:
+			problems = append(problems, fmt.Sprintf(
+				"%s's stream %q declares retention %q; a stream's retention is %q or nothing (novox/hq ADR 0436 §6)",
+				m.Module, s.Name, s.Retention, StreamRetentionWorkQueue))
+		}
+		switch {
+		case s.Retention == StreamRetentionWorkQueue &&
+			(s.MaxDeliveries < StreamLeastDeliveries || s.MaxDeliveries > StreamMostDeliveries):
+			problems = append(problems, fmt.Sprintf(
+				"%s's stream %q declares max-deliveries %d; a work-queue stream's max-deliveries is between %d "+
+					"and %d (novox/hq ADR 0436 §6)", m.Module, s.Name, s.MaxDeliveries, StreamLeastDeliveries,
+				StreamMostDeliveries))
+		case s.Retention != StreamRetentionWorkQueue && s.MaxDeliveries != 0:
+			problems = append(problems, fmt.Sprintf(
+				"%s's stream %q declares max-deliveries %d without retention %q (novox/hq ADR 0436 §6)",
+				m.Module, s.Name, s.MaxDeliveries, StreamRetentionWorkQueue))
+		}
+		switch {
+		case s.Duplicates != 0 && s.Retention != StreamRetentionWorkQueue:
+			problems = append(problems, fmt.Sprintf(
+				"%s's stream %q declares duplicates %d hours without retention %q (novox/hq ADR 0436 §6)",
+				m.Module, s.Name, s.Duplicates, StreamRetentionWorkQueue))
+		case s.Duplicates != 0 && s.Duplicates > s.Days()*24:
+			problems = append(problems, fmt.Sprintf(
+				"%s's stream %q keeps duplicates %d hours, longer than its maximum age of %d days (novox/hq "+
+					"ADR 0436 §6)", m.Module, s.Name, s.Duplicates, s.Days()))
+		}
+		if s.Retention == StreamRetentionWorkQueue && s.Grant != nil {
+			problems = append(problems, fmt.Sprintf(
+				"%s's stream %q declares retention %q carrying a grant; a work-queue stream is read by its "+
+					"module's one consumer, never granted (novox/hq ADR 0436 §6)", m.Module, s.Name, s.Retention))
+		}
 		if len(s.Events) == 0 {
 			problems = append(problems, fmt.Sprintf("%s declares stream %q with no events", m.Module, s.Name))
 		}
@@ -291,6 +351,64 @@ func patternsOverlap(a, b string) bool {
 	}
 }
 
+// WorkQueueStreamProblems refuses a work-queue stream (novox/hq ADR 0436 §6) that is not read by exactly
+// one process of its own module: named by none, it queues forever unconsumed; named by two, each would take
+// half of what the other needed, silently.
+func WorkQueueStreamProblems(m Manifest) []string {
+	var problems []string
+	named := map[string]int{}
+	for _, b := range m.ProcessBuses() {
+		for _, q := range b.Queues {
+			named[q]++
+		}
+	}
+	for _, s := range m.Streams {
+		if s.Retention != StreamRetentionWorkQueue {
+			continue
+		}
+		switch named[s.Name] {
+		case 0:
+			problems = append(problems, fmt.Sprintf(
+				"%s's work-queue stream %q: no process names it in bus.queues; a work-queue stream is read by "+
+					"exactly one process (novox/hq ADR 0436 §6)", m.Module, s.Name))
+		case 1:
+		default:
+			problems = append(problems, fmt.Sprintf(
+				"%s's work-queue stream %q: %d processes name it in bus.queues; a work-queue stream is read by "+
+					"exactly one (novox/hq ADR 0436 §6)", m.Module, s.Name, named[s.Name]))
+		}
+	}
+	return problems
+}
+
+// WorkQueueConsumedElsewhereProblems refuses another module's `consumes` naming a work-queue stream's events
+// (novox/hq ADR 0436 §6): read by its module's one process alone, never broadcast to a consumer that only
+// subscribes. Modelled on RestrictedHearingProblems.
+func WorkQueueConsumedElsewhereProblems(shelf Shelf) []string {
+	var problems []string
+	for _, module := range shelfOrder(shelf) {
+		m := shelf[module]
+		for _, c := range m.Consumes {
+			emitter, rest, named := strings.Cut(c, ".")
+			provider, known := shelf[emitter]
+			if !named || emitter == OneName || emitter == TheRest || !known || emitter == module {
+				continue
+			}
+			hearing, _ := provider.StreamsHearing(rest)
+			for _, s := range hearing {
+				if s.Retention != StreamRetentionWorkQueue {
+					continue
+				}
+				problems = append(problems, fmt.Sprintf(
+					"%s consumes %s, which %s's work-queue stream %s carries; a work-queue stream is read by "+
+						"its module's one process alone, never by another module's consumes (novox/hq ADR 0436 "+
+						"§6)", module, c, emitter, s.BusName()))
+			}
+		}
+	}
+	return problems
+}
+
 // StreamNameProblems are the rules about stream names no single manifest can be judged against: two
 // modules declaring one name.
 func StreamNameProblems(shelf Shelf) []string {

internal/catalogue/work_queue_consumer_test.go

@@ -0,0 +1,75 @@
+package catalogue
+
+import (
+	"strings"
+	"testing"
+)
+
+// A work-queue stream is read by exactly one process of its own module (novox/hq ADR 0436 §6): named once
+// in a process's bus.queues, and never asked for by another module's consumes.
+
+// mailSenderManifestWithQueue is the mesh-mail fixture (ADR 0436 §7, §8) with its process's bus.queues set
+// as given, so each 1178/AC2 case can vary just that.
+func mailSenderManifestWithQueue(queues string) Manifest {
+	return Manifest{
+		Module: "mesh-mail", Version: "1", Emits: []string{"mail.send.sent", "mail.send.failed"},
+		State: []StateDeclaration{{Name: "sends"}},
+		Streams: []StreamDeclaration{{Name: "mail-sends", Events: []string{"mail.send.approved"},
+			Retention: StreamRetentionWorkQueue, MaxDeliveries: 5}},
+		Resources: []map[string]any{
+			{"id": "account", "type": "user", "name": "mesh-mail-send"},
+			{"id": "send", "type": "process", "run": []any{"./mesh-mail", "send"}, "user": "mesh-mail-send",
+				"bus": map[string]any{"emits": []any{"mail.send.sent", "mail.send.failed"}, "queues": queueList(queues)}},
+		},
+	}
+}
+
+func queueList(q string) []any {
+	if q == "" {
+		return nil
+	}
+	out := []any{}
+	for _, s := range strings.Split(q, ",") {
+		out = append(out, s)
+	}
+	return out
+}
+
+// 1178/AC2 (named): a work-queue stream no process names is refused.
+func TestAWorkQueueStreamNoProcessNamesIsRefused(t *testing.T) {
+	m := mailSenderManifestWithQueue("")
+	got := strings.Join(WorkQueueStreamProblems(m), "; ")
+	if !strings.Contains(got, "mail-sends") || !strings.Contains(got, "no process names it") {
+		t.Fatalf("an unnamed work-queue stream: %q", got)
+	}
+}
+
+// 1178/AC2 (named twice): a work-queue stream two processes name is refused.
+func TestAWorkQueueStreamTwoProcessesNameIsRefused(t *testing.T) {
+	m := mailSenderManifestWithQueue("mail-sends")
+	m.Resources = append(m.Resources, map[string]any{"id": "resend", "type": "process",
+		"run": []any{"./mesh-mail", "send"}, "user": "mesh-mail-send",
+		"bus": map[string]any{"emits": []any{"mail.send.sent"}, "queues": []any{"mail-sends"}}})
+	got := strings.Join(WorkQueueStreamProblems(m), "; ")
+	if !strings.Contains(got, "mail-sends") || !strings.Contains(got, "2 processes name") {
+		t.Fatalf("a work-queue stream two processes name: %q", got)
+	}
+}
+
+// 1178/AC2 (named once): a work-queue stream exactly one process names is accepted.
+func TestAWorkQueueStreamOneProcessNamesIsAccepted(t *testing.T) {
+	m := mailSenderManifestWithQueue("mail-sends")
+	if got := WorkQueueStreamProblems(m); len(got) != 0 {
+		t.Fatalf("a work-queue stream one process names was refused: %v", got)
+	}
+}
+
+// 1178/AC2 (another module's consumes): a work-queue stream another module's consumes asks for is refused.
+func TestAWorkQueueStreamAnotherModulesConsumesIsRefused(t *testing.T) {
+	sender := mailSenderManifestWithQueue("mail-sends")
+	reader := Manifest{Module: "reader", Version: "1", Consumes: []string{"mesh-mail.mail.send.approved"}}
+	got := strings.Join(WorkQueueConsumedElsewhereProblems(Shelf{"mesh-mail": sender, "reader": reader}), "; ")
+	if !strings.Contains(got, "reader") || !strings.Contains(got, "MAIL_SENDS") {
+		t.Fatalf("another module's consumes of a work-queue stream: %q", got)
+	}
+}

internal/inventory/busrecords.go

@@ -187,6 +187,12 @@ func declaredFor(m catalogue.Manifest, seats map[string]catalogue.SeatDeclaratio
 		Logs: logsOf(m),
 		// And the streams it owns (novox/hq ADR 0363).
 		Streams: streamsOf(m),
+		// And its own work-queue streams, each with the one process its bus.queues names as the
+		// consumer (novox/hq ADR 0436 §1, §2, §6).
+		Queues: queueOwnersOf(m),
+		// And every process of its own that declares bus, each granted a bus account of its own (novox/hq
+		// ADR 0436 §1, §2).
+		Processes: ProcessesOf(m),
 		// And the tools its health asks (novox/hq ADR 0240): the machine's node-engine is granted them.
 		Checks: catalogue.HealthChecks(m),
 		// And whether it runs as an account of its own (novox/hq ADR 0259 §8).
@@ -422,7 +428,67 @@ func streamsOf(m catalogue.Manifest) []broker.ModuleStream {
 			events = append(events, broker.WirePattern(e))
 		}
 		out = append(out, broker.ModuleStream{Module: m.Module, Name: s.BusName(), Events: events,
-			MaxAgeDays: s.Days(), MaxMiB: s.Cap(), Restricted: s.Grant != nil})
+			MaxAgeDays: s.Days(), MaxMiB: s.Cap(), Restricted: s.Grant != nil,
+			WorkQueue: s.Retention == catalogue.StreamRetentionWorkQueue, Duplicates: s.Duplicates})
+	}
+	return out
+}
+
+// queueOwnersOf is every work-queue stream of a module's own that one of its processes names in bus.queues,
+// with that process's id and the stream's declared max-deliveries (novox/hq ADR 0436 §1, §2, §6). In
+// resource order, so composition is repeatable; a queue naming a stream the module does not own, or one two
+// processes name, is caught at registration (catalogue.WorkQueueStreamProblems) and never reaches here.
+func queueOwnersOf(m catalogue.Manifest) []broker.QueueOwner {
+	buses := m.ProcessBuses()
+	if len(buses) == 0 {
+		return nil
+	}
+	byName := map[string]catalogue.StreamDeclaration{}
+	for _, s := range m.Streams {
+		byName[s.Name] = s
+	}
+	var out []broker.QueueOwner
+	for _, r := range m.Resources {
+		id := fmt.Sprint(r["id"])
+		b, declared := buses[id]
+		if !declared {
+			continue
+		}
+		for _, q := range b.Queues {
+			s, known := byName[q]
+			if !known || s.Retention != catalogue.StreamRetentionWorkQueue {
+				continue
+			}
+			out = append(out, broker.QueueOwner{Process: id, Stream: s.BusName(), MaxDeliver: s.MaxDeliveries})
+		}
+	}
+	return out
+}
+
+// ProcessesOf is every process of a module that declares bus, as the broker composes its own account from
+// (novox/hq ADR 0436 §1, §2): its own emits, its own work-queue consumers (queueOwnersOf, filtered to each
+// process's own), its own state, whether it reads its module's own asks, and the tools and seat verbs it
+// calls.
+func ProcessesOf(m catalogue.Manifest) []broker.ProcessPrincipal {
+	buses := m.ProcessBuses()
+	if len(buses) == 0 {
+		return nil
+	}
+	queues := queueOwnersOf(m)
+	var out []broker.ProcessPrincipal
+	for _, r := range m.Resources {
+		id := fmt.Sprint(r["id"])
+		b, declared := buses[id]
+		if !declared {
+			continue
+		}
+		pr := broker.ProcessPrincipal{Process: id, Emits: b.Emits, State: b.State, Asks: b.Asks, Invokes: b.Invokes}
+		for _, q := range queues {
+			if q.Process == id {
+				pr.Queues = append(pr.Queues, q)
+			}
+		}
+		out = append(out, pr)
 	}
 	return out
 }

internal/inventory/bususers.go

@@ -68,6 +68,9 @@ const (
 	// BusProvisioner is a machine's provisioner client (novox/hq ADR 0349 clause 11, design 57 P3): an account of
 	// its own, named for the machine.
 	BusProvisioner = "provisioner"
+	// BusProcess is one process of a module that declares bus (novox/hq ADR 0436 §1, §2): an account of its
+	// own, named for the machine, the module and the process.
+	BusProcess = "process"
 )
 
 // MintBusPassword makes a bus password and records its hash under a username, replacing whatever was

internal/inventory/streams_test.go

@@ -43,3 +43,47 @@ func TestWhatAModuleHearsIsComposedOntoTheStreamsSubjects(t *testing.T) {
 		t.Fatalf("the provider's stream: %+v", got)
 	}
 }
+
+// 1177/AC1: a catalogue stream declaring retention work-queue is carried into the broker's ModuleStream as
+// WorkQueue, with its duplicate window.
+func TestAWorkQueueStreamIsCarriedIntoTheBrokersModuleStream(t *testing.T) {
+	sender := catalogue.Manifest{Module: "mesh-mail", Streams: []catalogue.StreamDeclaration{{Name: "mail-sends",
+		Events: []string{"mail.send.approved"}, MaxAgeDays: 1, MaxMiB: 64,
+		Retention: catalogue.StreamRetentionWorkQueue, MaxDeliveries: 5, Duplicates: 24}}}
+	got := streamsOf(sender)
+	if len(got) != 1 || got[0].Name != "MAIL_SENDS" || !got[0].WorkQueue || got[0].Duplicates != 24 {
+		t.Fatalf("the sender's stream: %+v", got)
+	}
+}
+
+// 1177/AC3: a catalogue stream with no retention is carried into the broker as not a work queue.
+func TestANonWorkQueueStreamIsCarriedAsNotAWorkQueue(t *testing.T) {
+	plain := catalogue.Manifest{Module: "feed", Streams: []catalogue.StreamDeclaration{{Name: "items",
+		Events: []string{"item.**"}}}}
+	got := streamsOf(plain)
+	if len(got) != 1 || got[0].WorkQueue || got[0].Duplicates != 0 {
+		t.Fatalf("the plain stream: %+v", got)
+	}
+}
+
+// 1178/AC1: the process a work-queue stream's bus.queues names is read from the manifest, by its resource
+// id, with the stream's own max-deliveries — what the broker composes the one durable consumer from.
+func TestTheQueueOwnersOfAWorkQueueStreamAreReadFromItsProcess(t *testing.T) {
+	sender := catalogue.Manifest{Module: "mesh-mail", Emits: []string{"mail.send.sent", "mail.send.failed"},
+		Streams: []catalogue.StreamDeclaration{{Name: "mail-sends", Events: []string{"mail.send.approved"},
+			Retention: catalogue.StreamRetentionWorkQueue, MaxDeliveries: 5}},
+		Resources: []map[string]any{
+			{"id": "account", "type": "user", "name": "mesh-mail-send"},
+			{"id": "send", "type": "process", "run": []any{"./mesh-mail", "send"}, "user": "mesh-mail-send",
+				"bus": map[string]any{"emits": []any{"mail.send.sent", "mail.send.failed"},
+					"queues": []any{"mail-sends"}}},
+		}}
+	got := queueOwnersOf(sender)
+	if len(got) != 1 || got[0].Process != "send" || got[0].Stream != "MAIL_SENDS" || got[0].MaxDeliver != 5 {
+		t.Fatalf("the sender's queue owners: %+v", got)
+	}
+	// And a module with no process declaring bus has none.
+	if got := queueOwnersOf(catalogue.Manifest{Module: "feed"}); got != nil {
+		t.Fatalf("a module with no process bus has queue owners: %+v", got)
+	}
+}

internal/link/deadletters.go

@@ -45,6 +45,10 @@ const (
 	// DeadHeaderAgesOut when its stream's maximum age runs out, counted from when it was first published.
 	DeadHeaderRestricted = "Mesh-Dead-Restricted"
 	DeadHeaderAgesOut    = "Mesh-Dead-Ages-Out"
+	// DeadHeaderWorkQueue says the message came from a work-queue stream (novox/hq ADR 0436 §6): aged and
+	// shown as a restricted stream's are (it sets DeadHeaderRestricted too), but never delivered again —
+	// only dropped.
+	DeadHeaderWorkQueue = "Mesh-Dead-Work-Queue"
 	// AgainHeader marks a message delivered again, with the kept copy's id it came from.
 	AgainHeader = "Mesh-Delivered-Again"
 )
@@ -74,6 +78,10 @@ type DeadLetter struct {
 	Restricted bool      `json:"restricted,omitempty"`
 	AgesOut    time.Time `json:"ages_out,omitzero"`
 	Withheld   string    `json:"withheld,omitempty"`
+	// WorkQueue says it came from a work-queue stream (novox/hq ADR 0436 §6): shown and aged as a restricted
+	// stream's are (Restricted is also set), but AgainTo refuses it unconditionally — only dropped, never
+	// delivered again.
+	WorkQueue bool `json:"work-queue,omitempty"`
 	// Body and Headers are the message itself, given only for one dead letter asked by its id, and never for
 	// a restricted one; a header with several values keeps them all.
 	Body    string              `json:"body,omitempty"`
@@ -91,17 +99,27 @@ const leastLeftToDeliver = time.Minute
 const withheldWords = "its body and its own headers are not shown: it came from a restricted stream, which only " +
 	"the modules its grant names may read (novox/hq ADR 0376)"
 
-// sourceAge is whether a stream is restricted (novox/hq ADR 0363 §4), and its maximum age: read from the stream
-// itself, where the controller says both. A stream that no longer exists is neither.
-func sourceAge(js nats.JetStreamContext, stream string) (bool, time.Duration, error) {
+// sourceAge is whether a stream is restricted (novox/hq ADR 0363 §4; a work-queue stream is restricted too,
+// novox/hq ADR 0436 §6, aged and hidden the same way), whether it is a module stream declared retention:
+// work-queue, and its maximum age: read from the stream itself, where the controller says all three. A
+// stream that no longer exists is neither.
+//
+// **The module declaration, never the bus's work-queue retention alone** (novox/hq ADR 0436 §6, found by
+// mesh-controller.try on d8249dad): SEAT_* and other mesh-internal streams are JetStream work queues too —
+// exactly one worker takes each ask (ADR 0264 §4) — and their dead letters are still delivered again. Only
+// a module stream the catalogue declared retention: work-queue says so in its own metadata
+// (broker.WorkQueueMetadata, set by ModuleStream.Stream() alone); checking the bus's retention policy
+// caught every seat's queue too and refused every ask ever given up on delivered again.
+func sourceAge(js nats.JetStreamContext, stream string) (restricted, workQueue bool, maxAge time.Duration, err error) {
 	info, err := js.StreamInfo(stream)
 	if errors.Is(err, nats.ErrStreamNotFound) {
-		return false, 0, nil
+		return false, false, 0, nil
 	}
 	if err != nil {
-		return false, 0, fmt.Errorf("whether %s is restricted cannot be read: %w", stream, err)
+		return false, false, 0, fmt.Errorf("whether %s is restricted cannot be read: %w", stream, err)
 	}
-	return info.Config.Metadata[broker.RestrictedMetadata] == "true", info.Config.MaxAge, nil
+	return info.Config.Metadata[broker.RestrictedMetadata] == "true",
+		info.Config.Metadata[broker.WorkQueueMetadata] == "true", info.Config.MaxAge, nil
 }
 
 // ttlOf is a time left as a message's time to live, in whole seconds and never more than what is left.
@@ -135,13 +153,16 @@ func KeepDeadLetter(js nats.JetStreamContext, notice []byte) (DeadLetter, error)
 	// **A restricted stream's message ages out with its stream** (novox/hq ADR 0376 §3): kept with a time to live
 	// of what is left of the stream's maximum age, counted from when it was first published; one already past it
 	// is kept as a record without its body. Every other dead letter keeps no age, as before (ADR 0264).
-	restricted, maxAge, err := sourceAge(js, a.Stream)
+	restricted, workQueue, maxAge, err := sourceAge(js, a.Stream)
 	if err != nil {
 		return DeadLetter{}, err
 	}
 	if restricted {
 		kept.Header.Set(DeadHeaderRestricted, "true")
 	}
+	if workQueue {
+		kept.Header.Set(DeadHeaderWorkQueue, "true")
+	}
 	raw, err := js.GetMsg(a.Stream, a.StreamSeq)
 	agesOut := time.Time{}
 	if err == nil && restricted && maxAge > 0 {
@@ -205,6 +226,7 @@ func deadLetterOf(id uint64, subject string, h nats.Header, data []byte, whole b
 	d.GaveUp, _ = time.Parse(time.RFC3339Nano, h.Get(DeadHeaderGaveUp))
 	d.Published, _ = time.Parse(time.RFC3339Nano, h.Get(DeadHeaderPublished))
 	d.Restricted = h.Get(DeadHeaderRestricted) == "true"
+	d.WorkQueue = h.Get(DeadHeaderWorkQueue) == "true"
 	d.AgesOut, _ = time.Parse(time.RFC3339Nano, h.Get(DeadHeaderAgesOut))
 	if whole {
 		d.Body = string(data)
@@ -349,6 +371,13 @@ func AgainTo(js nats.JetStreamContext, d DeadLetter) (string, error) {
 	case d.Subject == "":
 		return "", fmt.Errorf("dead letter %d does not say the subject it was published on, so it cannot be "+
 			"delivered again. Drop it", d.ID)
+	case d.WorkQueue:
+		// A work-queue stream's one consumer takes its messages in order (novox/hq ADR 0436 clause 6):
+		// delivering a given-up one back in would let it jump ahead of whatever the stream already holds, so
+		// unlike a module's ordinary stream (ADR 0363 §7) it is never delivered again, however much of its
+		// age is left.
+		return "", fmt.Errorf("dead letter %d is from %s, a work queue: it is only dropped, never delivered "+
+			"again (novox/hq ADR 0436 clause 6). Drop it", d.ID, d.Stream)
 	case broker.TheControllersAsk(d.Stream, d.Subject):
 		// The seat's worker takes it, and only while it is on the bus: without one the queue would keep
 		// the ask for a holder that may never come, and it would be let go as delivered meanwhile.
@@ -593,7 +622,7 @@ func AgingDeadLetters(js nats.JetStreamContext, held map[string]int) (map[string
 		stream, consumer, _ := strings.Cut(key, ".")
 		is, known := restricted[stream]
 		if !known {
-			r, _, err := sourceAge(js, stream)
+			r, _, _, err := sourceAge(js, stream)
 			if err != nil {
 				return nil, err
 			}

internal/link/deadletters_work_queue_test.go

@@ -0,0 +1,88 @@
+package link
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/nats-io/nats.go"
+
+	"github.com/novox/mesh-controller/internal/broker"
+)
+
+// A work-queue stream's dead letters are kept and shown as a restricted stream's are — aged with the
+// stream, never with their body or headers — and can only be dropped, never delivered again (novox/hq ADR
+// 0436 §6, changing ADR 0363 §7 for such a stream).
+
+// review round 1, finding 6 (1178/AC3): a work-queue stream really is restricted on the bus — its own
+// Stream() says so, and that is what EnsureStream's config sets the metadata from (jetstream.go's
+// streamConfigFor) — not merely a header this test set by hand, which would still pass with
+// modstreams.go's `out.Restricted = true` removed.
+func TestAWorkQueueStreamIsRestrictedOnTheBus(t *testing.T) {
+	mailSends := broker.ModuleStream{Module: "mesh-mail", Name: "MAIL_SENDS", Events: []string{"mail.send.approved"},
+		MaxAgeDays: 1, MaxMiB: 8, WorkQueue: true, Duplicates: 1}
+	stream := mailSends.Stream()
+	if !stream.Restricted {
+		t.Fatalf("a work-queue stream's own Stream() is not restricted: %+v", stream)
+	}
+	cfg := broker.StreamConfigFor(stream)
+	if cfg.Metadata[broker.RestrictedMetadata] != "true" {
+		t.Fatalf("the server config EnsureStream would send does not carry the restricted metadata: %+v", cfg.Metadata)
+	}
+}
+
+// mesh-controller.try fault A, d8249dad: a seat's own work queue (SEAT_*, novox/hq ADR 0190, ADR 0264 §4) is
+// a JetStream work queue at the bus level too — exactly one worker takes each ask — but it is never a module
+// stream the catalogue declared retention: work-queue (ADR 0436 §6), so it carries none of that clause's
+// metadata and its dead letters are still delivered again (ADR 0264 §4), unlike mail-sends'.
+func TestASeatsWorkQueueIsNotADR0436WorkQueue(t *testing.T) {
+	seatQueue := broker.Stream{Name: "SEAT_NODE_BUILD_AGENT", Retention: broker.RetentionWorkQueue, DiscardNew: true}
+	cfg := broker.StreamConfigFor(seatQueue)
+	if _, has := cfg.Metadata[broker.WorkQueueMetadata]; has {
+		t.Fatalf("a seat's own work queue carries ADR 0436 §6's metadata: %+v", cfg.Metadata)
+	}
+	if _, has := cfg.Metadata[broker.RestrictedMetadata]; has {
+		t.Fatalf("a seat's own work queue is restricted: %+v", cfg.Metadata)
+	}
+	// sourceAge (deadletters.go) reads exactly these two keys off a real stream's config; neither set means
+	// KeepDeadLetter marks a seat's dead letter WorkQueue: false, so AgainTo never reaches clause 6's
+	// drop-only case for it (proven directly in TestAWorkQueueDeadLetterIsNeverDeliveredAgain) and a seat's
+	// ask is still delivered again (ADR 0264 §4), as it was before this release.
+}
+
+// 1178/AC3: a dead letter's headers say it came from a work-queue stream, and reading it back carries that
+// (and the restricted flag its aging and hiding already key off, deadLetterOf being the one place both are
+// read: see DeadLetter.Restricted's doc).
+func TestAWorkQueueDeadLettersHeaderIsReadBack(t *testing.T) {
+	agesOut := time.Now().Add(time.Hour).UTC()
+	h := nats.Header{}
+	h.Set(DeadHeaderStream, "MAIL_SENDS")
+	h.Set(DeadHeaderConsumer, "novox_mesh-mail_send")
+	h.Set(DeadHeaderSubject, "mesh.stream.mesh-mail.event.mail.send.approved")
+	h.Set(DeadHeaderRestricted, "true")
+	h.Set(DeadHeaderWorkQueue, "true")
+	h.Set(DeadHeaderAgesOut, agesOut.Format(time.RFC3339Nano))
+
+	d := deadLetterOf(42, "mesh.stream.mesh-mail.event.mail.send.approved", h, []byte("secret body"), false)
+	if !d.WorkQueue {
+		t.Fatalf("a work-queue dead letter read as %+v", d)
+	}
+	if !d.Restricted {
+		t.Fatalf("a work-queue dead letter is not read as restricted, so it would be shown with its body: %+v", d)
+	}
+	if !d.AgesOut.Equal(agesOut) {
+		t.Fatalf("ages out at %v, want %v — it should age with its stream", d.AgesOut, agesOut)
+	}
+}
+
+// 1178/AC3: asking to deliver a work-queue dead letter again is refused, naming ADR 0436 clause 6 — before
+// anything is asked of the bus, so it holds whatever max-deliver or age is left.
+func TestAWorkQueueDeadLetterIsNeverDeliveredAgain(t *testing.T) {
+	d := DeadLetter{ID: 7, Stream: "MAIL_SENDS", Consumer: "novox_mesh-mail_send",
+		Subject: "mesh.stream.mesh-mail.event.mail.send.approved", WorkQueue: true, Restricted: true,
+		AgesOut: time.Now().Add(time.Hour)}
+	if _, err := AgainTo(nil, d); err == nil || !strings.Contains(err.Error(), "ADR 0436 clause 6") ||
+		!strings.Contains(err.Error(), "Drop it") {
+		t.Fatalf("delivering a work-queue dead letter again: %v; want a refusal naming ADR 0436 clause 6", err)
+	}
+}