diff --git a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/integration_test.go b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/integration_test.go
index 048f59d7..2d127854 100644
--- a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/integration_test.go
+++ b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/integration_test.go
@@ -873,16 +873,16 @@ func TestIndexerGivesACandidateItsFingerprintWhenTheCheckerCreatesThePreviewsBuc
 		if _, err := js.CreateOrUpdateConsumer(ctx, PreviewsStream, jetstream.ConsumerConfig{Durable: "n1_mesh-delivery-indexer", AckPolicy: jetstream.AckExplicitPolicy}); err != nil {
 			t.Fatal(err)
 		}
-		source, err := js.CreateKeyValue(ctx, jetstream.KeyValueConfig{Bucket: index.SourceBucket, History: 4})
-		if err != nil {
-			t.Fatal(err)
+		// The seat mesh-delivery's verb source, as the gate serves it (design 47 G §115): main names the catalogue's trunk head.
+		answer := func(m *nats.Msg) {
+			raw, _ := json.Marshal(map[string]any{"result": meshdelivery.SourceAnswer{Branch: "main", Group: "g", Revision: 5,
+				Repositories: []meshdelivery.SourceHead{{Repository: "novox/mesh-catalog", Head: trunk, Trunk: "main"}}}, "node": "n1"})
+			_ = m.Respond(raw)
 		}
-		data, err := meshdeliveryclient.EncodeSource(meshdelivery.SourceByMainValue{Group: "g", Heads: map[string]string{"novox/mesh-catalog": trunk}})
-		if err != nil {
-			t.Fatal(err)
-		}
-		if _, err := source.Put(ctx, meshdeliveryclient.SourceMainKey, data); err != nil {
-			t.Fatal(err)
+		for _, subject := range []string{"mesh.seat.mesh-delivery.call.source.>", "mesh.seat.mesh-delivery.tool.source"} {
+			if _, err := js.Conn().Subscribe(subject, answer); err != nil {
+				t.Fatal(err)
+			}
 		}
 	})
 	pull, err := forgemsg.EncodeForge(forgemsg.Forge{Kind: forgemsg.ForgePull, Repository: "novox/mesh-catalog", Branch: "feat/x", Number: 301, Head: head, Action: forgemsg.PullUpdated,
diff --git a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/main.go b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/main.go
index abd61bd5..01e3af36 100644
--- a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/main.go
+++ b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/main.go
@@ -22,6 +22,7 @@ import (
 	"syscall"
 	"time"
 
+	"git.novox.be/novox/mesh-delivery/contracts/go/seats/meshdelivery"
 	"github.com/nats-io/nats.go"
 	"github.com/nats-io/nats.go/jetstream"
 
@@ -470,22 +471,11 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 			"indexed from it, until the indexer starts again", builds.BuildLogRead, err)
 	}
 	started.Store(true)
-	// The gate's source bucket (mesh-delivery-gate_source) comes with the gate (release 3e, novox/hq ADR 0450 §1): its key
-	// main is the mesh's source revision, which stamps the modules (issue 1344). Where it does not exist yet the indexer does
-	// not wait for it (that needs a timer, ADR 0437 §8): it says so, and is started again with the gate.
-	sourceErrs := make(chan error, 1)
-	if source := process.OptionalBucket(ctx, js, index.SourceBucket, "no source revision is read until the indexer starts again", logger.Printf); source != nil {
-		each := func(e jetstream.KeyValueEntry) {
-			if opOf(e) {
-				applySource(ctx, ix, e.Key(), e.Revision(), e.Value(), logger)
-			}
-		}
-		if sw, err := settle(ctx, source, each); err != nil {
-			process.NotWatched(logger.Printf, index.SourceBucket, err, "no source revision is read until the indexer starts again")
-		} else {
-			go func() { sourceErrs <- follow(ctx, sw, each) }()
-		}
-	}
+	// The source revision of a watched branch (design 47 G §15, §115, §362): asked of the seat mesh-delivery's verb source as a
+	// kept call, once at the start, before the handler of its event source-moved reads anything; a source-moved heard
+	// meanwhile is read after.
+	source := &sourceFollow{read: sourceVia(calls.CallKept), apply: ix.ApplySource, logf: logger.Printf}
+	go source.catchUp(ctx)
 	// Only the toolchain reports of nodes the catalogue places the build module on count (issue 1940, ADR 0549 §3): the
 	// assignments is settled first, so the toolchains settle through the gate already knowing it.
 	gate := buildrun.NewToolchainGate(sortedModules(), ix.PutToolchain, logger.Printf)
@@ -668,6 +658,9 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 	}); err != nil {
 		return err
 	}
+	if err := hub.Handle(meshdelivery.SubjectSourceMovedAll, func(m jetstream.Msg) { source.heard(ctx, m) }); err != nil {
+		return err
+	}
 	hub.OnBound(reads.atBind) // what a node's engine said before the consumer was bound (ADR 0668 §4)
 	versions := func(m jetstream.Msg) {
 		if !heardVersion(ctx, ix, m, logger.Printf) {
@@ -753,8 +746,6 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 		return nil
 	case err := <-errs:
 		return err
-	case err := <-sourceErrs:
-		return err
 	case err := <-assignmentsErrs:
 		return err
 	case err := <-tools.errs:
diff --git a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/main_test.go b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/main_test.go
index e64afeeb..1450b161 100644
--- a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/main_test.go
+++ b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/main_test.go
@@ -5,7 +5,9 @@ import (
 	"context"
 	"encoding/json"
 	"errors"
+	"fmt"
 	"log"
+	"reflect"
 	"strings"
 	"testing"
 	"time"
@@ -16,7 +18,6 @@ import (
 	"git.novox.be/novox/mesh-contracts/go/seats/nodeengine"
 	mcc "git.novox.be/novox/mesh-contracts/health-and-repair/go/clients/meshconditionsclient"
 	"git.novox.be/novox/mesh-contracts/health-and-repair/go/seats/meshwatchdogs"
-	"git.novox.be/novox/mesh-delivery/contracts/go/clients/meshdeliveryclient"
 	"git.novox.be/novox/mesh-delivery/contracts/go/seats/meshdelivery"
 	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-forge-bridge/forgemsg"
 	"git.novox.be/novox/mesh-sdk/go/process"
@@ -237,24 +238,64 @@ type opener struct{ err error }
 
 func (o opener) KeyValue(context.Context, string) (jetstream.KeyValue, error) { return nil, o.err }
 
-func TestTheSourceMainKeyIsTakenAtItsRevision(t *testing.T) { // 1344/AC1 (the watch's side: key, revision, value)
-	var logs bytes.Buffer
-	logger := log.New(&logs, "", 0)
-	mods := &memStore{vals: map[string][]byte{}}
-	ix := &index.Indexer{Store: &memStore{vals: map[string][]byte{}}, Modules: mods, Builds: index.NewBuilds()}
-	value, err := meshdeliveryclient.EncodeSource(meshdelivery.SourceByMainValue{Group: "g", Heads: map[string]string{"novox/mesh-delivery": head}})
-	if err != nil {
-		t.Fatal(err)
+func TestTheSourceIsReadFromTheSeatAndASourceMovedDuringTheCatchUpIsReadAfterIt(t *testing.T) { // design 47 G §15, §115, §362
+	var order []string
+	revision := int64(4)
+	var logs []string
+	var s *sourceFollow
+	s = &sourceFollow{
+		read: func(branch string) (meshdelivery.SourceAnswer, error) {
+			order = append(order, "read "+branch)
+			if revision == 0 {
+				return meshdelivery.SourceAnswer{}, fmt.Errorf("source.main is not readable")
+			}
+			if len(order) == 1 { // a source-moved is heard while the catch-up reads
+				s.moved(context.Background(), "main")
+				s.moved(context.Background(), "main")
+				s.moved(context.Background(), "beta")
+			}
+			return meshdelivery.SourceAnswer{Branch: branch, Revision: revision}, nil
+		},
+		apply: func(_ context.Context, a meshdelivery.SourceAnswer) error {
+			order = append(order, fmt.Sprintf("apply %s %d", a.Branch, a.Revision))
+			return nil
+		},
+		logf: func(f string, a ...any) { logs = append(logs, fmt.Sprintf(f, a...)) },
 	}
-	applySource(context.Background(), ix, "other", 3, value, logger) // not the key of the mesh's source
-	applySource(context.Background(), ix, meshdeliveryclient.SourceMainKey, 4, []byte(`{"v":1`), logger)
-	if !strings.Contains(logs.String(), "source") {
-		t.Errorf("a source that cannot be read was not said: %q", logs.String())
+	s.catchUp(context.Background())
+	want := []string{"read main", "apply main 4", "read main", "apply main 4"} // once, after the catch-up; beta is left
+	if !reflect.DeepEqual(order, want) {
+		t.Errorf("order = %v, want %v", order, want)
 	}
-	logs.Reset()
-	applySource(context.Background(), ix, meshdeliveryclient.SourceMainKey, 5, value, logger)
-	if logs.Len() != 0 {
-		t.Errorf("a good source said %q", logs.String())
+	s.moved(context.Background(), "main") // after the catch-up: read at once
+	if len(order) != 6 {
+		t.Errorf("a source-moved after the catch-up was not read at once: %v", order)
+	}
+	order, revision = nil, 0
+	s.moved(context.Background(), "main")
+	if len(order) != 1 || len(logs) != 1 || !strings.Contains(logs[0], "not readable") {
+		t.Errorf("a source that cannot be read: order %v, said %v, want it said and nothing applied", order, logs)
+	}
+}
+
+func TestTheSeatsSourceAnswerIsReadAndItsErrorIsAnError(t *testing.T) { // design 47 G §115
+	var asked any
+	read := sourceVia(func(key string, body any) (json.RawMessage, error) {
+		asked = body
+		if key != "seat:mesh-delivery.source" {
+			t.Errorf("asked %q", key)
+		}
+		if body.(meshdelivery.SourceInput).Branch == "bad" {
+			return json.RawMessage(`{"error":"source.bad is not readable"}`), nil
+		}
+		return json.RawMessage(`{"branch":"main","revision":7,"repositories":[{"repository":"novox/mesh-delivery","head":"` + head + `","trunk":"main"}]}`), nil
+	})
+	a, err := read("main")
+	if err != nil || a.Revision != 7 || len(a.Repositories) != 1 || asked.(meshdelivery.SourceInput).Branch != "main" {
+		t.Errorf("source = %+v, %v", a, err)
+	}
+	if _, err := read("bad"); err == nil || !strings.Contains(err.Error(), "not readable") {
+		t.Errorf("an answer with an error was no error: %v", err)
 	}
 }
 
diff --git a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/source.go b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/source.go
index f8aaaad1..10f92615 100644
--- a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/source.go
+++ b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/source.go
@@ -2,26 +2,100 @@ package main
 
 import (
 	"context"
-	"log"
+	"encoding/json"
+	"fmt"
+	"strings"
+	"sync"
 
-	"git.novox.be/novox/mesh-delivery/contracts/go/clients/meshdeliveryclient"
-
-	"mesh-delivery-indexer/internal/index"
+	"git.novox.be/novox/mesh-delivery/contracts/go/seats/meshdelivery"
+	"github.com/nats-io/nats.go/jetstream"
 )
 
-// applySource takes one put of the gate's bucket source into the indexer: the key main, at its revision, which is the mesh's
-// source revision (mesh-sdk go/delivery SourceMainKey, Source). Any other key is not the mesh's source. A value that is no
-// source is said; so is a write that failed, and it is tried again only at the next revision (novox/hq ADR 0437 §8).
-func applySource(ctx context.Context, ix *index.Indexer, key string, rev uint64, value []byte, logger *log.Logger) {
-	if key != meshdeliveryclient.SourceMainKey {
+// sourceInvoke is the seat mesh-delivery's verb source as the manifest's invokes names it: a watched branch's source
+// revision, asked of the seat and never read from the gate's state (design 47 G §15, §115; ADR 0596 §2).
+const sourceInvoke = "seat:" + meshdelivery.Seat + "." + meshdelivery.VerbSource
+
+// sourceVia asks the seat for one branch's source revision through call (process.Conn.CallKept, a read) and reads its
+// declared answer; an answer that carries an error is that error.
+func sourceVia(call toolCaller) func(branch string) (meshdelivery.SourceAnswer, error) {
+	return func(branch string) (meshdelivery.SourceAnswer, error) {
+		raw, err := call(sourceInvoke, meshdelivery.SourceInput{Branch: branch})
+		if err != nil {
+			return meshdelivery.SourceAnswer{}, err
+		}
+		var a meshdelivery.SourceAnswer
+		if err := json.Unmarshal(raw, &a); err != nil {
+			return a, fmt.Errorf("the answer of %s is not a source revision: %w", sourceInvoke, err)
+		}
+		if a.Error != "" {
+			return a, fmt.Errorf("%s: %s", sourceInvoke, a.Error)
+		}
+		return a, nil
+	}
+}
+
+// sourceFollow takes the seat's source revisions into the indexer: first the catch-up of the heads the source names, then
+// each source-moved the seat says (design 47 G §362). A source-moved heard before the catch-up ended is applied after it,
+// once per branch.
+type sourceFollow struct {
+	read  func(branch string) (meshdelivery.SourceAnswer, error)
+	apply func(context.Context, meshdelivery.SourceAnswer) error
+	logf  func(string, ...any)
+
+	mu      sync.Mutex
+	caught  bool
+	waiting map[string]bool
+}
+
+// catchUp reads the trunk branch's source revision and applies it, then the branches a source-moved named meanwhile. A
+// read that fails is said; the catch-up ends all the same, and the next source-moved reads again.
+func (s *sourceFollow) catchUp(ctx context.Context) {
+	s.take(ctx, trunkBranch)
+	s.mu.Lock()
+	s.caught = true
+	branches := s.waiting
+	s.waiting = nil
+	s.mu.Unlock()
+	for branch := range branches {
+		s.take(ctx, branch)
+	}
+}
+
+// moved is the handler of one source-moved on branch: held until the catch-up ends, read at once after.
+func (s *sourceFollow) moved(ctx context.Context, branch string) {
+	s.mu.Lock()
+	if !s.caught {
+		if s.waiting == nil {
+			s.waiting = map[string]bool{}
+		}
+		s.waiting[branch] = true
+		s.mu.Unlock()
 		return
 	}
-	s, err := meshdeliveryclient.DecodeSource(value)
+	s.mu.Unlock()
+	s.take(ctx, branch)
+}
+
+// take reads one branch's source revision and applies it. A branch other than the trunk's is left until the indexer keeps
+// a catalog graph per watched branch.
+func (s *sourceFollow) take(ctx context.Context, branch string) {
+	if branch != trunkBranch {
+		return
+	}
+	a, err := s.read(branch)
 	if err != nil {
-		logger.Printf("source.%s at revision %d is not a source, and is left: %v", key, rev, err)
+		s.logf("source.%s is not read, and is read again at its next source-moved: %v", branch, err)
 		return
+	}
+	if err := s.apply(ctx, a); err != nil {
+		s.logf("source.%s at revision %d could not be taken into the modules: %v", branch, a.Revision, err)
 	}
-	if err := ix.ApplySource(ctx, rev, s); err != nil {
-		logger.Printf("source.%s at revision %d could not be taken into the modules: %v", key, rev, err)
+}
+
+// heard is the hub's handler of source-moved: the branch is the last token of the subject. The message is acknowledged at once.
+func (s *sourceFollow) heard(ctx context.Context, m jetstream.Msg) {
+	defer func() { _ = m.Ack() }()
+	if branch := m.Subject()[strings.LastIndex(m.Subject(), ".")+1:]; branch != "" {
+		s.moved(ctx, branch)
 	}
 }
diff --git a/modules/mesh-delivery-indexer/internal/index/inputs_test.go b/modules/mesh-delivery-indexer/internal/index/inputs_test.go
index 74763916..77adda62 100644
--- a/modules/mesh-delivery-indexer/internal/index/inputs_test.go
+++ b/modules/mesh-delivery-indexer/internal/index/inputs_test.go
@@ -144,7 +144,7 @@ func TestAnArtifactOfNoToolchainHasNoLanguageAndNoLock(t *testing.T) { // 1450/A
 func TestAManifestTheParserRefusesLeavesNoInputsAndSaysWhy(t *testing.T) { // 1450/AC5
 	for name, raw := range map[string]string{
 		"not json":      "not json",
-		"unknown field": strings.Replace(catalogueManifest(t, "avahi"), `"version":"1.0",`, `"version":"1.0", "scope": "everything",`, 1),
+		"unknown field": strings.Replace(catalogueManifest(t, "avahi"), `"version": "1",`, `"version": "1", "scope": "everything",`, 1),
 	} {
 		in := inputsOf("avahi", raw, "t", nil, noBases)
 		if in.Kept != nil || !strings.HasPrefix(in.None2, "the manifest cannot be read: ") || len(in.None2) <= len("the manifest cannot be read: ") {
diff --git a/modules/mesh-delivery-indexer/internal/index/modules_test.go b/modules/mesh-delivery-indexer/internal/index/modules_test.go
index 1d3b78fe..9a4d6fc7 100644
--- a/modules/mesh-delivery-indexer/internal/index/modules_test.go
+++ b/modules/mesh-delivery-indexer/internal/index/modules_test.go
@@ -14,7 +14,6 @@ import (
 
 	"git.novox.be/novox/mesh-delivery/contracts/go/clients/meshcatalogclient"
 	"git.novox.be/novox/mesh-delivery/contracts/go/seats/meshcatalog"
-	"git.novox.be/novox/mesh-delivery/contracts/go/seats/meshdelivery"
 	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/builds"
 	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-forge-bridge/forgemsg"
 	"git.novox.be/novox/mesh-delivery/sdk/trunk"
@@ -160,7 +159,7 @@ func TestAnUnchangedModuleWritesNothing(t *testing.T) { // 1239 (unchanged value
 				if err := ix.Apply(context.Background(), m); err != nil {
 					return err
 				}
-				if err := ix.ApplySource(context.Background(), 8, sourceOf(repo, next)); err != nil {
+				if err := applyS(ix, context.Background(), 8, sourceOf(repo, next)); err != nil {
 					return err
 				}
 				ix.Taken = on
@@ -169,7 +168,7 @@ func TestAnUnchangedModuleWritesNothing(t *testing.T) { // 1239 (unchanged value
 		{name: "a source head whose merge was not applied is not a taken key", writes: 0, commit: map[string]string{"a": merge, "b": merge, "c": merge}, taken: "",
 			then: func(ix *Indexer) error { // the forge stream still holds the merge: the consumer is not drained
 				delete(ix.Taken.(*memStore).vals, takenKey(repo))
-				if err := ix.ApplySource(context.Background(), 8, sourceOf(repo, next)); err != nil {
+				if err := applyS(ix, context.Background(), 8, sourceOf(repo, next)); err != nil {
 					return err
 				}
 				return ix.FillTaken(context.Background())
@@ -180,7 +179,7 @@ func TestAnUnchangedModuleWritesNothing(t *testing.T) { // 1239 (unchanged value
 		{name: "a source head of a drained forge stream whose merge was never heard leaves the key", writes: 0, commit: map[string]string{"a": merge, "b": merge, "c": merge}, taken: merge,
 			then: func(ix *Indexer) error {
 				ix.Contains = func(_ context.Context, _, commit, in string) (bool, error) { return commit == merge && in == next, nil }
-				if err := ix.ApplySource(context.Background(), 8, sourceOf(repo, next)); err != nil {
+				if err := applyS(ix, context.Background(), 8, sourceOf(repo, next)); err != nil {
 					return err
 				}
 				return ix.FillTaken(context.Background())
@@ -188,7 +187,7 @@ func TestAnUnchangedModuleWritesNothing(t *testing.T) { // 1239 (unchanged value
 		{name: "a source head of a drained forge stream fills no missing key", writes: 0, commit: map[string]string{"a": merge, "b": merge, "c": merge}, taken: "",
 			then: func(ix *Indexer) error {
 				delete(ix.Taken.(*memStore).vals, takenKey(repo))
-				if err := ix.ApplySource(context.Background(), 8, sourceOf(repo, next)); err != nil {
+				if err := applyS(ix, context.Background(), 8, sourceOf(repo, next)); err != nil {
 					return err
 				}
 				return ix.FillTaken(context.Background())
@@ -300,7 +299,7 @@ func TestAnUnchangedModuleWritesNothing(t *testing.T) { // 1239 (unchanged value
 			}},
 		{name: "a later source revision of another repository's merge", writes: 0, commit: map[string]string{"a": merge, "b": merge, "c": merge}, taken: merge,
 			then: func(ix *Indexer) error {
-				return ix.ApplySource(context.Background(), 9, meshdelivery.SourceByMainValue{Group: "g", Heads: map[string]string{repo: merge, "novox/mesh-catalog": otherMerge}})
+				return applyS(ix, context.Background(), 9, srcT{Group: "g", Heads: map[string]string{repo: merge, "novox/mesh-catalog": otherMerge}})
 			}},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
@@ -311,7 +310,7 @@ func TestAnUnchangedModuleWritesNothing(t *testing.T) { // 1239 (unchanged value
 			if err := ix.Apply(ctx, mergedMsg(repo, three)); err != nil {
 				t.Fatal(err)
 			}
-			if err := ix.ApplySource(ctx, 7, sourceOf(repo, merge)); err != nil {
+			if err := applyS(ix, ctx, 7, sourceOf(repo, merge)); err != nil {
 				t.Fatal(err)
 			}
 			writes := mods.writes
@@ -379,7 +378,7 @@ func TestAMergeWritesTheModulesDirectoryAndKeepsItThroughSourceAndRecompute(t *t
 			t.Errorf("after the merge %s = %+v (%v), want path %q", module, m, ok, want)
 		}
 	}
-	if err := ix.ApplySource(ctx, 7, sourceOf("novox/mesh-delivery", merge)); err != nil {
+	if err := applyS(ix, ctx, 7, sourceOf("novox/mesh-delivery", merge)); err != nil {
 		t.Fatal(err)
 	}
 	if err := ix.Recompute(ctx); err != nil {
diff --git a/modules/mesh-delivery-indexer/internal/index/names.go b/modules/mesh-delivery-indexer/internal/index/names.go
index 6d950393..e3d860d9 100644
--- a/modules/mesh-delivery-indexer/internal/index/names.go
+++ b/modules/mesh-delivery-indexer/internal/index/names.go
@@ -40,7 +40,6 @@ const (
 	AssignmentsState      = "assignments"
 	AssignmentsBucket     = AssignerModule + "_" + AssignmentsState
 	AssignmentsHistory    = 5
-	SourceBucket          = GateModule + "_source"
 	PreviewsBucket        = CheckerModule + "_previews"
 	PreviewsHistory       = 5
 	toolchainsState       = "toolchains"
diff --git a/modules/mesh-delivery-indexer/internal/index/previews_test.go b/modules/mesh-delivery-indexer/internal/index/previews_test.go
index 26201cd4..efd893b2 100644
--- a/modules/mesh-delivery-indexer/internal/index/previews_test.go
+++ b/modules/mesh-delivery-indexer/internal/index/previews_test.go
@@ -17,7 +17,6 @@ import (
 
 	"git.novox.be/novox/mesh-delivery/contracts/go/clients/meshcatalogclient"
 	"git.novox.be/novox/mesh-delivery/contracts/go/seats/meshcatalog"
-	"git.novox.be/novox/mesh-delivery/contracts/go/seats/meshdelivery"
 	"git.novox.be/novox/mesh-delivery/contracts/go/seats/meshdeliverychecker"
 	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-checker/checkermsg"
 	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-forge-bridge/forgemsg"
@@ -39,7 +38,7 @@ func previewBed(t *testing.T, report bool) (*Indexer, *memStore, *memStore) {
 	if report {
 		reportToolchain(t, ix, "mesh-build-go", "novox", "go", "go1.27.1")
 	}
-	if err := ix.ApplySource(context.Background(), 5, meshdelivery.SourceByMainValue{Group: "g", Heads: map[string]string{catalogueRepo: trunkNow}}); err != nil {
+	if err := applyS(ix, context.Background(), 5, srcT{Group: "g", Heads: map[string]string{catalogueRepo: trunkNow}}); err != nil {
 		t.Fatal(err)
 	}
 	return ix, mods, ix.Store.(*memStore)
@@ -205,7 +204,7 @@ func TestAPreviewMadeOntoAnOldTrunkIsOutOfDate(t *testing.T) { // 1445/AC3
 	if got := fpOf(t, cands); got.Fp2 == "" {
 		t.Fatalf("after the right preview: %+v", got)
 	}
-	if err := ix.ApplySource(context.Background(), 6, meshdelivery.SourceByMainValue{Group: "g", Heads: map[string]string{catalogueRepo: "8888888888888888888888888888888888888888"}}); err != nil {
+	if err := applyS(ix, context.Background(), 6, srcT{Group: "g", Heads: map[string]string{catalogueRepo: "8888888888888888888888888888888888888888"}}); err != nil {
 		t.Fatal(err)
 	}
 	if got := fpOf(t, cands); got.None2 != NonePreviewStale {
diff --git a/modules/mesh-delivery-indexer/internal/index/registered_test.go b/modules/mesh-delivery-indexer/internal/index/registered_test.go
index 6492329e..c2437640 100644
--- a/modules/mesh-delivery-indexer/internal/index/registered_test.go
+++ b/modules/mesh-delivery-indexer/internal/index/registered_test.go
@@ -9,7 +9,6 @@ import (
 
 	"git.novox.be/novox/mesh-delivery/contracts/go/clients/meshcatalogclient"
 	"git.novox.be/novox/mesh-delivery/contracts/go/seats/meshcatalog"
-	"git.novox.be/novox/mesh-delivery/contracts/go/seats/meshdelivery"
 	"git.novox.be/novox/mesh-sdk/go/keys"
 )
 
@@ -261,7 +260,7 @@ func TestAForgeThatCannotSayLeavesTheModuleUnwrittenAndAsksAgain(t *testing.T) {
 					t.Fatal(err)
 				}
 			case "a new source revision":
-				if err := ix.ApplySource(ctx, 2, meshdelivery.SourceByMainValue{Heads: map[string]string{"jschoubben/snake": h2, "novox/other": h1}}); err != nil {
+				if err := applyS(ix, ctx, 2, srcT{Heads: map[string]string{"jschoubben/snake": h2, "novox/other": h1}}); err != nil {
 					t.Fatal(err)
 				}
 				ix.retryWG.Wait() // read again in the background
@@ -281,7 +280,7 @@ func TestAForgeThatCannotSayLeavesTheModuleUnwrittenAndAsksAgain(t *testing.T) {
 			}
 			// Taken in, it is read no more: a further event asks the forge nothing.
 			n := len(asked)
-			if err := ix.ApplySource(ctx, 3, meshdelivery.SourceByMainValue{Heads: map[string]string{"jschoubben/snake": h2}}); err != nil {
+			if err := applyS(ix, ctx, 3, srcT{Heads: map[string]string{"jschoubben/snake": h2}}); err != nil {
 				t.Fatal(err)
 			}
 			ix.retryWG.Wait()
diff --git a/modules/mesh-delivery-indexer/internal/index/remove_test.go b/modules/mesh-delivery-indexer/internal/index/remove_test.go
index 8c1b5042..e5864ca2 100644
--- a/modules/mesh-delivery-indexer/internal/index/remove_test.go
+++ b/modules/mesh-delivery-indexer/internal/index/remove_test.go
@@ -100,7 +100,7 @@ func TestAPathWithoutAModuleJSONIsNeverAModule(t *testing.T) { // 1900/AC2: test
 func TestStartingDeletesTheKeysTheTrunkDoesNotHold(t *testing.T) { // 1900/AC3
 	ix, mods := twoModules(t)
 	ctx := context.Background()
-	if err := ix.ApplySource(ctx, 3, sourceOf(catalogueRepo, merge)); err != nil {
+	if err := applyS(ix, ctx, 3, sourceOf(catalogueRepo, merge)); err != nil {
 		t.Fatal(err)
 	}
 	var asked string
@@ -126,7 +126,7 @@ func TestStartingDeletesTheKeysTheTrunkDoesNotHold(t *testing.T) { // 1900/AC3
 func TestStartingDeletesNothingWhenTheTrunkCannotBeRead(t *testing.T) { // 1900/AC3: failure is loud, never a mass delete
 	ix, mods := twoModules(t)
 	ctx := context.Background()
-	if err := ix.ApplySource(ctx, 3, sourceOf(catalogueRepo, merge)); err != nil {
+	if err := applyS(ix, ctx, 3, sourceOf(catalogueRepo, merge)); err != nil {
 		t.Fatal(err)
 	}
 	for name, trunk := range map[string]func(context.Context, string, string) ([]string, error){
@@ -146,7 +146,7 @@ func TestAKeyWrittenAheadOfTheSourceHeadStaysAndOneWithoutAPathIsSkipped(t *test
 	ix, mods := twoModules(t) // written at the merge commit C
 	ctx := context.Background()
 	const older = "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"
-	if err := ix.ApplySource(ctx, 3, sourceOf(catalogueRepo, older)); err != nil {
+	if err := applyS(ix, ctx, 3, sourceOf(catalogueRepo, older)); err != nil {
 		t.Fatal(err)
 	}
 	mods.put("nopath", mustEncode(t, meshcatalog.ModulesByModuleValue{Repository: catalogueRepo, Commit: older, None2: "x", Manifest: strings.Repeat("a", 64)}))
diff --git a/modules/mesh-delivery-indexer/internal/index/source.go b/modules/mesh-delivery-indexer/internal/index/source.go
index 2b67be36..62123afe 100644
--- a/modules/mesh-delivery-indexer/internal/index/source.go
+++ b/modules/mesh-delivery-indexer/internal/index/source.go
@@ -11,8 +11,9 @@ import (
 	"git.novox.be/novox/mesh-delivery/sdk/trunk"
 )
 
-// The gate's source revision (novox/hq ADR 0437 §5, ADR 0450 §1): source.main names every repository's merged head, and its
-// revision in the bucket is the mesh's source revision. The indexer keeps the latest it has seen. A module is stamped
+// The gate's source revision of a watched branch (design 47 G §15, §115), read through the seat mesh-delivery's verb source
+// and its event source-moved, never the gate's state: it names every repository's merged head, and its revision is the
+// mesh's source revision of that branch. The indexer keeps the latest it has seen. A module is stamped
 // with it (Module.Src) when the head the source names for its repository is the merge commit the module's fingerprint
 // was computed at: from the modules bucket when the merge was heard first, and when the merge is heard after the source.
 
@@ -33,12 +34,17 @@ func (ix *Indexer) srcOf(repository, merge string) uint64 {
 	return 0
 }
 
-// ApplySource takes a revision of the gate's source.main in. An older revision than the latest seen is left. For each
+// ApplySource takes the source revision the verb source answered in. An older revision than the latest seen is left. For each
 // repository the source names, each module built from it whose fingerprint was computed at the head the source names, and
 // that carries no Src yet, is written again with Src the revision (once: a later revision leaves it); a module computed at another commit is left (a merge heard later is stamped
 // when it is written, applyMerged), and a repository none of the indexer's modules is built from writes nothing. The
 // modules of a repository are those the modules bucket holds of it (ADR 0501 clause 6).
-func (ix *Indexer) ApplySource(ctx context.Context, rev uint64, s meshdelivery.SourceByMainValue) error {
+func (ix *Indexer) ApplySource(ctx context.Context, a meshdelivery.SourceAnswer) error {
+	rev := uint64(a.Revision)
+	s := struct{ Heads map[string]string }{Heads: map[string]string{}}
+	for _, r := range a.Repositories {
+		s.Heads[r.Repository] = r.Head
+	}
 	ix.kickJudge(ctx)
 	ix.mu.Lock()
 	if rev < ix.source.rev {
diff --git a/modules/mesh-delivery-indexer/internal/index/source_test.go b/modules/mesh-delivery-indexer/internal/index/source_test.go
index 0bed051a..9fc5b906 100644
--- a/modules/mesh-delivery-indexer/internal/index/source_test.go
+++ b/modules/mesh-delivery-indexer/internal/index/source_test.go
@@ -10,8 +10,20 @@ import (
 
 const otherMerge = "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"
 
-func sourceOf(repo, head string) meshdelivery.SourceByMainValue {
-	return meshdelivery.SourceByMainValue{Group: "g", Heads: map[string]string{repo: head}}
+// srcT is a source revision's heads as the tests write them; applyS says it as the verb source answers it.
+type srcT struct {
+	Group string
+	Heads map[string]string
+}
+
+func sourceOf(repo, head string) srcT { return srcT{Group: "g", Heads: map[string]string{repo: head}} }
+
+func applyS(ix *Indexer, ctx context.Context, rev uint64, s srcT) error {
+	a := meshdelivery.SourceAnswer{Branch: "main", Group: s.Group, Revision: int64(rev)}
+	for r, h := range s.Heads {
+		a.Repositories = append(a.Repositories, meshdelivery.SourceHead{Repository: r, Head: h, Trunk: "main"})
+	}
+	return ix.ApplySource(ctx, a)
 }
 
 func TestASourceRevisionStampsTheModulesOfTheRepositoriesHeadItNames(t *testing.T) { // 1344/AC1
@@ -25,8 +37,8 @@ func TestASourceRevisionStampsTheModulesOfTheRepositoriesHeadItNames(t *testing.
 		t.Fatalf("module before the source = %+v, want Src 0", before)
 	}
 	// The source names the head merged for the delivery repository, and another repository's head no module of ours is built from.
-	s := meshdelivery.SourceByMainValue{Group: "g", Heads: map[string]string{"novox/mesh-delivery": merge, "novox/mesh-catalog": otherMerge}}
-	if err := ix.ApplySource(ctx, 7, s); err != nil {
+	s := srcT{Group: "g", Heads: map[string]string{"novox/mesh-delivery": merge, "novox/mesh-catalog": otherMerge}}
+	if err := applyS(ix, ctx, 7, s); err != nil {
 		t.Fatal(err)
 	}
 	m, ok := moduleOf(t, mods, "a")
@@ -39,10 +51,10 @@ func TestASourceRevisionStampsTheModulesOfTheRepositoriesHeadItNames(t *testing.
 		t.Errorf("module c = %+v: written for a head no merge message of the indexer carried", c)
 	}
 	// The same revision again changes nothing, and so does a later one: Src is the first revision naming the commit.
-	if err := ix.ApplySource(ctx, 7, s); err != nil {
+	if err := applyS(ix, ctx, 7, s); err != nil {
 		t.Fatal(err)
 	}
-	if err := ix.ApplySource(ctx, 9, s); err != nil {
+	if err := applyS(ix, ctx, 9, s); err != nil {
 		t.Fatal(err)
 	}
 	if m, _ := moduleOf(t, mods, "a"); m.Src != 7 {
@@ -56,15 +68,15 @@ func TestAMergeHeardAfterTheSourceNamesItsHeadIsStampedWhenWritten(t *testing.T)
 		ix, mods := modulesIndexer(t, rec(t, "build-1", "a", "novox/mesh-delivery", "modules/a", "main", "", "2026-10-19T09:00:00Z", aInputs))
 		ctx := context.Background()
 		_ = ix.Apply(ctx, mergedMsg("novox/mesh-delivery", map[string]string{"modules/a": "newtree"}))
-		_ = ix.ApplySource(ctx, 9, sourceOf("novox/mesh-delivery", merge))
-		_ = ix.ApplySource(ctx, 7, sourceOf("novox/mesh-delivery", merge))
+		_ = applyS(ix, ctx, 9, sourceOf("novox/mesh-delivery", merge))
+		_ = applyS(ix, ctx, 7, sourceOf("novox/mesh-delivery", merge))
 		if m, _ := moduleOf(t, mods, "a"); m.Src != 9 {
 			t.Errorf("module a Src = %d, want 9", m.Src)
 		}
 	})
 	ix, mods := modulesIndexer(t, rec(t, "build-1", "a", "novox/mesh-delivery", "modules/a", "main", "", "2026-10-19T09:00:00Z", aInputs))
 	ctx := context.Background()
-	if err := ix.ApplySource(ctx, 7, sourceOf("novox/mesh-delivery", merge)); err != nil {
+	if err := applyS(ix, ctx, 7, sourceOf("novox/mesh-delivery", merge)); err != nil {
 		t.Fatal(err)
 	}
 	if _, ok := moduleOf(t, mods, "a"); ok {
@@ -89,7 +101,7 @@ func TestAMergeThatNoSourceRevisionNamesIsWrittenAsToday(t *testing.T) { // 1344
 		t.Fatalf("module a = %+v (%v), want the merge written with Src 0", m, ok)
 	}
 	// A source revision that names another head of the repository: a merge of the head it does not name keeps Src 0.
-	if err := ix.ApplySource(ctx, 7, sourceOf("novox/mesh-delivery", otherMerge)); err != nil {
+	if err := applyS(ix, ctx, 7, sourceOf("novox/mesh-delivery", otherMerge)); err != nil {
 		t.Fatal(err)
 	}
 	if m, _ := moduleOf(t, mods, "a"); m.Src != 0 {
diff --git a/modules/mesh-delivery-indexer/internal/index/stale_none2_test.go b/modules/mesh-delivery-indexer/internal/index/stale_none2_test.go
index 6ec511d1..e92d94b7 100644
--- a/modules/mesh-delivery-indexer/internal/index/stale_none2_test.go
+++ b/modules/mesh-delivery-indexer/internal/index/stale_none2_test.go
@@ -10,7 +10,7 @@ import (
 // not read.
 func unreadableAvahi(t *testing.T) string {
 	t.Helper()
-	raw := strings.Replace(catalogueManifest(t, "avahi"), `"version":"1.0",`, `"version":"1.0", "scope": "everything",`, 1)
+	raw := strings.Replace(catalogueManifest(t, "avahi"), `"version": "1",`, `"version": "1", "scope": "everything",`, 1)
 	if raw == catalogueManifest(t, "avahi") {
 		t.Fatal("the fixture has no version line")
 	}
diff --git a/modules/mesh-delivery-indexer/internal/index/toolchains_test.go b/modules/mesh-delivery-indexer/internal/index/toolchains_test.go
index 16eb83ce..17667eef 100644
--- a/modules/mesh-delivery-indexer/internal/index/toolchains_test.go
+++ b/modules/mesh-delivery-indexer/internal/index/toolchains_test.go
@@ -15,7 +15,6 @@ import (
 
 	"git.novox.be/novox/mesh-delivery/contracts/go/clients/meshcatalogclient"
 	"git.novox.be/novox/mesh-delivery/contracts/go/seats/meshcatalog"
-	"git.novox.be/novox/mesh-delivery/contracts/go/seats/meshdelivery"
 	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-builder/builds"
 	"git.novox.be/novox/mesh-delivery/modules/mesh-delivery-forge-bridge/forgemsg"
 	sdkstep "git.novox.be/novox/mesh-delivery/sdk/buildstep"
@@ -38,7 +37,7 @@ func renamed(t *testing.T, from, to string) string {
 	if out == raw {
 		t.Fatalf("%s's manifest has no module line", from)
 	}
-	return out
+	return strings.Replace(out, `"version": "1",`, `"version": "1.0",`, 1) // the validator reads MAJOR.MINOR only (design 47 G §368)
 }
 
 func standingOn(t *testing.T, raw, base string) string {
@@ -150,8 +149,8 @@ func TestAgreedToolchainChangesAGoModulesReasonWithNoMerge(t *testing.T) { // 14
 	}
 	// The release that last merged avahi: its source revision names avahi's commit, so Src (and FPSrc) are 7.
 	merged, _ := moduleOf(t, mods, "avahi")
-	src := meshdelivery.SourceByMainValue{Group: "g", Heads: map[string]string{merged.Repository: merged.Commit}}
-	if err := ix.ApplySource(context.Background(), 7, src); err != nil {
+	src := srcT{Group: "g", Heads: map[string]string{merged.Repository: merged.Commit}}
+	if err := applyS(ix, context.Background(), 7, src); err != nil {
 		t.Fatal(err)
 	}
 	if m, _ := moduleOf(t, mods, "avahi"); m.Src != 7 || m.FpSrc != 7 {
@@ -183,7 +182,7 @@ func TestAgreedToolchainChangesAGoModulesReasonWithNoMerge(t *testing.T) { // 14
 	if m.FpSrc != 0 {
 		t.Errorf("a fingerprint moved by a recompute: fp-src %d, want 0", m.FpSrc)
 	}
-	if err := ix.ApplySource(context.Background(), 8, src); err != nil {
+	if err := applyS(ix, context.Background(), 8, src); err != nil {
 		t.Fatal(err)
 	}
 	if again, _ := moduleOf(t, mods, "avahi"); again.FpSrc != 0 {
@@ -344,7 +343,7 @@ func TestBasesAreComputedFirstAndNoFingerprintTakesTheBuilder(t *testing.T) { //
 	// verb edges of two modules calling each other, from either side; a third calling one of them keeps its edge.
 	invoking := func(name, invokes string) mod {
 		raw := renamed(t, "avahi", name)
-		return mod{name, strings.Replace(raw, `"version":"1.0",`, `"version":"1.0", "invokes": [`+invokes+`],`, 1)}
+		return mod{name, strings.Replace(raw, `"version": "1.0",`, `"version": "1.0", "invokes": [`+invokes+`],`, 1)}
 	}
 	vx, _ := newFormIndexer(t, invoking("caller", `"callee.avahi_status"`), invoking("callee", `"caller.avahi_browse", "*"`),
 		invoking("third", `"callee.avahi_status"`))
diff --git a/modules/mesh-delivery-indexer/manifest_test.go b/modules/mesh-delivery-indexer/manifest_test.go
index 09028dc2..cb7db957 100644
--- a/modules/mesh-delivery-indexer/manifest_test.go
+++ b/modules/mesh-delivery-indexer/manifest_test.go
@@ -130,14 +130,14 @@ func TestManifestDeclarations(t *testing.T) { // 1238/AC1, 1444 (reads the build
 			t.Errorf("the indexer names its bucket %s with %d revisions, its manifest's states are %+v", bucket, history, m.State)
 		}
 	}
-	for bucket, read := range map[string]string{index.SourceBucket: "mesh-delivery-gate.source", index.PreviewsBucket: "mesh-delivery-checker.previews",
+	for bucket, read := range map[string]string{index.PreviewsBucket: "mesh-delivery-checker.previews",
 		index.ToolchainsBucket(index.BuildGoModule): "mesh-build-go.toolchains", index.ToolchainsBucket(index.BuildNodeModule): "mesh-build-node.toolchains"} {
 		if !slices.Contains(m.Reads, read) || strings.Replace(read, ".", "_", 1) != bucket {
 			t.Errorf("the indexer reads the bucket %s, its manifest's reads are %v (want %s)", bucket, m.Reads, read)
 		}
 	}
 	// DLV-F1r (ADR 0615 §1): the assigner's assignments is read through its first view and views family, never its state.
-	if want := []string{"mesh-build-go.toolchains", "mesh-build-node.toolchains", "mesh-delivery-builder.build-log", "mesh-delivery-checker.previews", "mesh-delivery-gate.source"}; !reflect.DeepEqual(sorted(m.Reads), want) {
+	if want := []string{"mesh-build-go.toolchains", "mesh-build-node.toolchains", "mesh-delivery-builder.build-log", "mesh-delivery-checker.previews"}; !reflect.DeepEqual(sorted(m.Reads), want) {
 		t.Errorf("reads = %v, want %v", m.Reads, want)
 	}
 	// "Reads FORGE" is a consumes of the indexer's stream: the broker grants only buckets by reads (mesh-control
@@ -145,7 +145,7 @@ func TestManifestDeclarations(t *testing.T) { // 1238/AC1, 1444 (reads the build
 	// The registry seats' published and the builder's numbered fill each package's series (DLV-I5, design 51 *The versions*).
 	if want := []string{"go-package-registry.published", "mesh-build-go.toolchain.reported", "mesh-build-node.toolchain.reported", "mesh-delivery-assigner.views.assignments",
 		"mesh-delivery-builder.version.numbered", "mesh-delivery-checker.preview.written", "mesh-delivery-checker.try.ended", "mesh-delivery-checker.try.started", "mesh-delivery-checker.verdict", "mesh-delivery-forge-bridge.forge.**",
-		"node-engine.manifest-reads-changed", "npm-package-registry.published"}; !reflect.DeepEqual(sorted(m.Consumes), want) { // ADR 0632 §2: the counted engines' reads
+		"mesh-delivery.source-moved", "node-engine.manifest-reads-changed", "npm-package-registry.published"}; !reflect.DeepEqual(sorted(m.Consumes), want) { // ADR 0632 §2: the counted engines' reads
 		t.Errorf("consumes = %v, want %v", m.Consumes, want)
 	}
 	if b, ok := m.OwnSecrets["broker"]; !ok || len(m.OwnSecrets) != 1 || b != "${dir:state}/broker" {
@@ -157,7 +157,7 @@ func TestManifestDeclarations(t *testing.T) { // 1238/AC1, 1444 (reads the build
 	// Three invokes: the file of a registered module's manifest and lock files (registered.go), the forge's trees (the named paths' objects, since the indexer is the one reader of a manifest's paths:
 	// ADR 0499 clauses 2 and 3, ADR 0495 clause 1; and the module directories of the trunk, issue 1900) and whether a
 	// commit is in another (issue 1900).
-	if want := []string{"mesh-delivery-assigner.assignments", "gitea.gitea_commit_trees", "gitea.gitea_contains", "gitea.gitea_get_file", "gitea.gitea_open_pulls", "mesh-delivery-checker.checker_tries", "mesh-delivery-forge-bridge.bridge_merged_message", "seat:node-engine.composition", "seat:node-engine.manifest-reads", "seat:mesh-hand-acts.hand-act", "seat:mesh-watchdogs.presence"}; !reflect.DeepEqual(m.Invokes, want) {
+	if want := []string{"mesh-delivery-assigner.assignments", "gitea.gitea_commit_trees", "gitea.gitea_contains", "gitea.gitea_get_file", "gitea.gitea_open_pulls", "mesh-delivery-checker.checker_tries", "mesh-delivery-forge-bridge.bridge_merged_message", "seat:node-engine.composition", "seat:node-engine.manifest-reads", "seat:mesh-delivery.source", "seat:mesh-hand-acts.hand-act", "seat:mesh-watchdogs.presence"}; !reflect.DeepEqual(m.Invokes, want) {
 		t.Errorf("invokes = %v, want %v", m.Invokes, want)
 	}
 	// 1945: indexer_take_in, served by its tools bundle through the takeins state; the process serves none. The same bundle
diff --git a/modules/mesh-delivery-indexer/module.json b/modules/mesh-delivery-indexer/module.json
index c820abfc..0392d211 100644
--- a/modules/mesh-delivery-indexer/module.json
+++ b/modules/mesh-delivery-indexer/module.json
@@ -69,6 +69,7 @@
     "mesh-delivery-checker.try.started",
     "mesh-delivery-checker.verdict",
     "mesh-delivery-forge-bridge.forge.**",
+    "mesh-delivery.source-moved",
     "node-engine.manifest-reads-changed",
     "npm-package-registry.published"
   ],
@@ -118,8 +119,7 @@
     "mesh-build-go.toolchains",
     "mesh-build-node.toolchains",
     "mesh-delivery-builder.build-log",
-    "mesh-delivery-checker.previews",
-    "mesh-delivery-gate.source"
+    "mesh-delivery-checker.previews"
   ],
   "invokes": [
     "mesh-delivery-assigner.assignments",
@@ -131,6 +131,7 @@
     "mesh-delivery-forge-bridge.bridge_merged_message",
     "seat:node-engine.composition",
     "seat:node-engine.manifest-reads",
+    "seat:mesh-delivery.source",
     "seat:mesh-hand-acts.hand-act",
     "seat:mesh-watchdogs.presence"
   ],