The control plane prepares its own state, like any module

Now that every parser on the mesh knows the word, the control plane's manifest says it. Its schema
stops being a special case: the mesh derives the step from its own resource and gates its server on
it, which is the failure of novox/hq 04-ISSUES/133 closed by the mechanism rather than by a
hand-written step in one manifest.

cmd/mesh-builder/main.go

@@ -194,6 +194,9 @@ func answer(ctx context.Context, publisher builder.Publisher, on, workspace stri
 				})
 			}
 			result.Against = built.Against
+			for _, r := range built.Read {
+				result.Read = append(result.Read, link.ReadRepository{Repository: r.Repository, Ref: r.Ref})
+			}
 			fmt.Fprintf(os.Stderr, "  built %s from %s\n", built.Manifest.Module, short(built.Commit))
 		}
 	}

cmd/mesh-builder/once.go

@@ -106,6 +106,9 @@ func buildOnce(ctx context.Context, args []string) error {
 		Manifest:   built.Manifest,
 		Against:    built.Against,
 	}
+	for _, r := range built.Read {
+		out.Read = append(out.Read, readRepository{Repository: r.Repository, Ref: r.Ref})
+	}
 	for _, made := range built.Built {
 		out.Made = append(out.Made, madeArtifact{Name: made.Name, Kind: made.Kind, Reference: made.Reference})
 	}
@@ -123,14 +126,21 @@ func buildOnce(ctx context.Context, args []string) error {
 // The same fields the mesh records for a build, so a reader comparing a genesis build against an
 // ordinary one is comparing the same thing said the same way.
 type onceResult struct {
-	Module     string         `json:"module"`
-	Commit     string         `json:"commit"`
-	Repository string         `json:"repository"`
-	Path       string         `json:"path,omitempty"`
-	Ref        string         `json:"ref,omitempty"`
-	Manifest   any            `json:"manifest"`
-	Made       []madeArtifact `json:"made"`
-	Against    []string       `json:"against,omitempty"`
+	Module     string           `json:"module"`
+	Commit     string           `json:"commit"`
+	Repository string           `json:"repository"`
+	Path       string           `json:"path,omitempty"`
+	Ref        string           `json:"ref,omitempty"`
+	Manifest   any              `json:"manifest"`
+	Made       []madeArtifact   `json:"made"`
+	Against    []string         `json:"against,omitempty"`
+	Read       []readRepository `json:"read,omitempty"`
+}
+
+// readRepository is a repository this build read source from besides the module's own.
+type readRepository struct {
+	Repository string `json:"repository"`
+	Ref        string `json:"ref,omitempty"`
 }
 
 type madeArtifact struct {

cmd/mesh-controller/build.go

@@ -149,6 +149,9 @@ func buildFrom(result link.BuildResult) inventory.Build {
 	for _, ref := range result.Against {
 		kept.Against = append(kept.Against, catalogue.Recorded(ref))
 	}
+	for _, r := range result.Read {
+		kept.Read = append(kept.Read, inventory.ReadRepository{Repository: r.Repository, Ref: r.Ref})
+	}
 	var announced []inventory.Artifact
 	for _, made := range result.Made {
 		announced = append(announced, inventory.Artifact{

cmd/mesh-controller/main.go

@@ -76,7 +76,10 @@ func run() error {
 		return pinCommand(ctx, args[1:], true)
 	case "unpin":
 		return pinCommand(ctx, args[1:], false)
-	case "migrate":
+	// `prepare` is how the mesh asks any module to bring its state to the shape this version needs
+	// (novox/hq ADR 0135), and the control plane answers it the same way as everything else — its
+	// own schema is not a special case. `migrate` remains the word a person types.
+	case "prepare", "migrate":
 		return migrate(ctx)
 	case "node":
 		return nodeCommand(ctx, args[1:])
@@ -138,6 +141,7 @@ func usage() {
 	fmt.Fprint(os.Stderr, `mesh-controller — the control plane
 
   migrate                        bring each context's schema up to date
+  prepare                        the same, asked the way the mesh asks any module (ADR 0135)
   node add <name> [--adopted]    create a node record; --adopted: the machine is in use
   node list                      the nodes this mesh knows about
   node show <name>               what one machine reported it can do, and why

cmd/mesh-controller/modules.go

@@ -69,12 +69,20 @@ func moduleCommand(ctx context.Context, args []string) error {
 		repo := set.String("source", "", "where this module comes from")
 		ref := set.String("ref", "", "the branch followed there")
 		commit := set.String("commit", "", "the commit this manifest was read at")
+		// **Where inside the repository the module is** (novox/hq ADR 0069). A module is a
+		// repository *and* a directory, and a record that carries only the repository names a
+		// module.json at its root — so every later build of it looks in the wrong place and fails
+		// with "no module.json at its root". Nine modules on this mesh were registered that way
+		// and none of them could be rebuilt (2026-09-28).
+		path := set.String("path", "", "the module's directory inside that repository")
+		self := set.Bool("self", false, "the source is a path on the forge holding the git seat")
 		positionals, err := parseAround(set, args[1:])
 		if err != nil {
 			return err
 		}
 		if len(positionals) != 1 {
-			return errors.New("module add <manifest.json> [--source <repo> --ref <branch> --commit <sha>]")
+			return errors.New("module add <manifest.json> [--source <repo> [--self] [--path P] " +
+				"--ref <branch> --commit <sha>]")
 		}
 		raw, err := os.ReadFile(positionals[0])
 		if err != nil {
@@ -84,23 +92,24 @@ func moduleCommand(ctx context.Context, args []string) error {
 		if err != nil {
 			return err
 		}
-		// Provenance together or not at all. A source with no commit cannot be compared against
-		// anything, so it would record where the module came from and still never be able to say
-		// the mesh is behind it — which is the one thing recording it is for.
-		if (*repo == "") != (*commit == "") {
-			return errors.New("--source and --commit go together: a source with no commit " +
-				"cannot be compared against anything, and a commit with no source has nothing " +
-				"to be compared with")
+		from, err := whereItComesFrom(*repo, *ref, *commit, *path, *self)
+		if err != nil {
+			return err
 		}
-		if err := inv.RegisterModule(ctx, m, inventory.Source{
-			Repository: *repo, Ref: *ref, BuiltFrom: *commit,
-		}); err != nil {
+		if err := inv.RegisterModule(ctx, m, from); err != nil {
 			return err
 		}
 		fmt.Printf("%s registered", m.Module)
 		if *commit != "" {
 			fmt.Printf(" from %s", short(*commit))
 		}
+		if *repo != "" && *path == "" {
+			// Said, not refused: a module really at the root is the ordinary case for a repository
+			// of its own. But a repository holding many modules and a record naming none of them is
+			// a module nothing can rebuild, and the person adding it is the one who knows which.
+			fmt.Printf("\n  no directory inside %s, so it is built from that repository's root — "+
+				"`--path` if the module lives in a directory there", *repo)
+		}
 		if len(m.Provides) > 0 {
 			fmt.Printf(", providing %s", describeOffers(m.Provides))
 		}
@@ -602,3 +611,37 @@ func issueWith(ctx context.Context, inv *inventory.Inventory, m catalogue.Manife
 		"machine holding mesh-broker\n")
 	return nil
 }
+
+// whereItComesFrom is the provenance a module handed over by hand records, and what a record must
+// say to be worth anything later.
+//
+// **A module is a repository and a directory inside it** (novox/hq ADR 0069). A record carrying only
+// the repository names a module.json at its root, so every later build of it looks in the wrong
+// place — nine modules on this mesh were registered that way and none of them could be rebuilt
+// (2026-09-28). The directory cannot be checked from here, because the control plane does not clone;
+// what can be checked is that the record is whole.
+func whereItComesFrom(repository, ref, commit, path string, self bool) (inventory.Source, error) {
+	// Provenance together or not at all. A source with no commit cannot be compared against
+	// anything, so it would record where the module came from and still never be able to say the
+	// mesh is behind it — which is the one thing recording it is for.
+	if (repository == "") != (commit == "") {
+		return inventory.Source{}, errors.New("--source and --commit go together: a source with " +
+			"no commit cannot be compared against anything, and a commit with no source has " +
+			"nothing to be compared with")
+	}
+	// A directory or a forge with no repository is half a location, and the half it keeps is the
+	// half nothing can be found with.
+	if repository == "" && (path != "" || self) {
+		return inventory.Source{}, errors.New("--path and --self say where inside a source and " +
+			"which forge holds it, so they need --source: without one there is nothing for them " +
+			"to be part of")
+	}
+	from := inventory.Source{Repository: repository, Ref: ref, BuiltFrom: commit, Path: path}
+	if self {
+		if err := onASeat(repository); err != nil {
+			return inventory.Source{}, err
+		}
+		from.Seat = gitSeat
+	}
+	return from, nil
+}

cmd/mesh-controller/operator.go

@@ -189,13 +189,17 @@ func readPrivateKey(path string) (string, error) {
 func personIssue(ctx context.Context, args []string) error {
 	set := flag.NewFlagSet("operator issue", flag.ContinueOnError)
 	invokes := set.String("invokes", "", "the tools this person may call, comma-separated, or * for every one")
-	if err := set.Parse(args); err != nil {
+	// Flags on either side of the name, because the usage this command prints puts them after it —
+	// and the standard parser stops at the first thing that is not a flag, so the order the command
+	// documents was the one order it refused (2026-09-28).
+	positionals, err := parseAround(set, args)
+	if err != nil {
 		return err
 	}
-	if set.NArg() != 1 {
+	if len(positionals) != 1 {
 		return errors.New("operator issue <name> --invokes <tool,tool|*>")
 	}
-	name := set.Arg(0)
+	name := positionals[0]
 	if *invokes == "" {
 		return errors.New(
 			"say what this person may call: --invokes mesh-catalog.catalog_tools,gitea.repo_create, " +

cmd/mesh-controller/order_test.go

@@ -3,6 +3,7 @@ package main
 import (
 	"strings"
 	"testing"
+	"time"
 
 	"github.com/novox/mesh-controller/internal/catalogue"
 	"github.com/novox/mesh-controller/internal/inventory"
@@ -90,3 +91,122 @@ func TestAMergeMatchesTheSourcesBuiltFromIt(t *testing.T) {
 		}
 	}
 }
+
+// A merge made before the source was last seen is history: it does not move the source, and a
+// merge that says nothing about when it was made is taken as news.
+func TestAMergeOlderThanTheLastLookIsHistory(t *testing.T) {
+	seen := time.Date(2026, 9, 28, 3, 0, 0, 0, time.UTC)
+	if !isHistory("2026-09-28T02:00:00Z", seen) {
+		t.Fatal("an older merge was taken as news")
+	}
+	if isHistory("2026-09-28T04:00:00Z", seen) {
+		t.Fatal("a newer merge was taken as history")
+	}
+	if isHistory("", seen) || isHistory("2026-09-28T02:00:00Z", time.Time{}) {
+		t.Fatal("a merge or a source with no time on it was refused")
+	}
+}
+
+// A module as the catalogue holds it: built from a repository, at a directory inside it.
+func fromRepo(module, repository, path string) inventory.Entry {
+	return inventory.Entry{
+		Manifest: catalogue.Manifest{Module: module},
+		Source:   inventory.Source{Repository: repository, Path: path, Ref: "main"},
+	}
+}
+
+// A merge rebuilds the modules whose own directories it changed, and everything when what it changed
+// is shared. One repository holding many modules is the ordinary case here, and rebuilding all of
+// them for a change to one is what exhausted a registry's pull limit the first night this ran.
+func TestAMergeRebuildsTheModulesItChanged(t *testing.T) {
+	const repo = "http://forge.internal:20000/novox/mesh-catalog.git"
+	gitea := fromRepo("gitea", repo, "modules/gitea")
+	keycloak := fromRepo("keycloak", repo, "modules/keycloak")
+	known := []inventory.Entry{gitea, keycloak, fromRepo("plex", repo, "modules/plex")}
+	candidates := []inventory.Entry{gitea, keycloak}
+	merge := func(paths []string, truncated bool) link.SourceMoved {
+		return link.SourceMoved{Owner: "novox", Repo: "mesh-catalog", Base: "main",
+			Paths: paths, PathsTruncated: truncated}
+	}
+	named := func(entries []inventory.Entry) string {
+		var names []string
+		for _, e := range entries {
+			names = append(names, e.Manifest.Module)
+		}
+		return strings.Join(names, ",")
+	}
+	for _, c := range []struct {
+		what string
+		m    link.SourceMoved
+		want string
+	}{
+		{"one module's own files", merge([]string{"modules/gitea/index.ts", "modules/gitea/client.ts"}, false), "gitea"},
+		{"two modules' files", merge([]string{"modules/gitea/index.ts", "modules/keycloak/module.json"}, false), "gitea,keycloak"},
+		{"a file they share", merge([]string{"tsconfig.json"}, false), "gitea,keycloak"},
+		{"a module the mesh does not hold", merge([]string{"modules/plex/index.ts"}, false), ""},
+		{"nothing said about the files", merge(nil, false), "gitea,keycloak"},
+		{"more files than were listed", merge([]string{"modules/gitea/index.ts"}, true), "gitea,keycloak"},
+	} {
+		if got := named(whatTheMergeTouched(candidates, known, c.m)); got != c.want {
+			t.Errorf("%s: rebuilt %q, wanted %q", c.what, got, c.want)
+		}
+	}
+}
+
+// A module whose recipe packages source from another repository is affected when that repository
+// moves — the manifest the mesh keeps says nothing about it, so the record of what the build read is
+// the only thing that can say so.
+func TestAModuleIsAffectedByTheRepositoryItPackages(t *testing.T) {
+	m := link.SourceMoved{Owner: "novox", Repo: "mesh-controller", Base: "main",
+		CloneURL: "http://forge.internal:20000/novox/mesh-controller.git"}
+	for _, read := range [][]inventory.ReadRepository{
+		{{Repository: "http://forge.internal:20000/novox/mesh-controller.git", Ref: "main"}},
+		{{Repository: "novox/mesh-controller"}},
+		{{Repository: "https://elsewhere.example/novox/other"}, {Repository: "novox/mesh-controller.git", Ref: "main"}},
+	} {
+		if !readsFrom(read, m) {
+			t.Errorf("%+v was not matched by the merge", read)
+		}
+	}
+	for _, read := range [][]inventory.ReadRepository{
+		nil,
+		{{Repository: "novox/mesh-host", Ref: "main"}},
+		{{Repository: "novox/mesh-controller", Ref: "release"}},
+	} {
+		if readsFrom(read, m) {
+			t.Errorf("%+v was matched by a merge that is not its", read)
+		}
+	}
+}
+
+// What a module handed over by hand records about where it came from, and what is refused.
+func TestWhatAHandedOverModuleRecordsAboutItsSource(t *testing.T) {
+	// The whole location: a repository on the mesh's own forge, the directory inside it, the branch
+	// and the commit the manifest was read at.
+	from, err := whereItComesFrom("novox/mesh-catalog", "main", "c0ffee", "modules/gitea", true)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if from.Path != "modules/gitea" || from.Seat != "git" || from.Repository != "novox/mesh-catalog" {
+		t.Fatalf("the source records as %+v", from)
+	}
+	// A manifest with no provenance at all is legitimate: fixing something in a hurry.
+	if from, err := whereItComesFrom("", "", "", "", false); err != nil || from != (inventory.Source{}) {
+		t.Fatalf("a manifest handed over with no provenance was refused: %+v, %v", from, err)
+	}
+	for _, c := range []struct {
+		what                          string
+		repository, ref, commit, path string
+		self                          bool
+	}{
+		{what: "a source with no commit", repository: "novox/mesh-catalog", commit: ""},
+		{what: "a commit with no source", commit: "c0ffee"},
+		{what: "a directory inside nothing", path: "modules/gitea"},
+		{what: "a forge holding nothing", self: true},
+		{what: "an address given as a path on the forge", repository: "http://forge.internal:20000/novox/x.git", commit: "c0ffee", self: true},
+	} {
+		if _, err := whereItComesFrom(c.repository, c.ref, c.commit, c.path, c.self); err == nil {
+			t.Errorf("%s was recorded as a source", c.what)
+		}
+	}
+}

cmd/mesh-controller/push.go

@@ -753,8 +753,31 @@ func raiseTheBus(ctx context.Context, inv *inventory.Inventory, address string)
 	if err := broker.RaiseSeats(js, inventory.MeshSeats(), holders); err != nil {
 		return err
 	}
-	fmt.Printf("the bus at %s has its streams, and %d machine(s) can hear a declaration\n",
-		broker.BareAddress(address), len(names))
+	// And how every module hears what it consumes. Derived from the same records the user list is
+	// composed from, so a module the mesh grants a consumer's subjects has that consumer waiting.
+	// Done on every raise, not only when a credential is issued: every module moved onto this bus
+	// by the rollout was issued on the old one, and came up with nothing to bind to (2026-09-28).
+	records, err := inv.BusRecords(ctx)
+	if err != nil {
+		return err
+	}
+	users, err := broker.Users(records)
+	if err != nil {
+		return err
+	}
+	hearing := 0
+	for _, p := range users {
+		consumer, needed := broker.ConsumerFor(p)
+		if !needed {
+			continue
+		}
+		if err := js.EnsureConsumer(consumer); err != nil {
+			return fmt.Errorf("how %s on %s hears what it consumes: %w", p.Module, p.Node, err)
+		}
+		hearing++
+	}
+	fmt.Printf("the bus at %s has its streams, %d machine(s) can hear a declaration, and %d module(s) "+
+		"can hear what they consume\n", broker.BareAddress(address), len(names), hearing)
 	return nil
 }
 

cmd/mesh-controller/rollout.go

@@ -127,9 +127,13 @@ func readinessOf(ctx context.Context, inv *inventory.Inventory) (broker.Readines
 	if address != "" {
 		// One dial, briefly. "Is it answering" is the one fact records cannot hold, and a mesh about
 		// to move onto a server that is not there should hear it here rather than afterwards.
-		if conn, err := nats.Connect(broker.BareAddress(address), nats.Timeout(5*time.Second)); err == nil {
+		//
+		// **Dialled the way the mesh dials it** — credential and pin — because a bare connect to a
+		// bus that requires TLS and a user fails at the handshake, and the check then reported a
+		// standing server as absent (seen live, 2026-09-28).
+		if js, err := broker.Dial(address, nats.Timeout(5*time.Second)); err == nil {
 			state.ServerStanding = true
-			conn.Close()
+			js.Close()
 		}
 	}
 

cmd/mesh-controller/upgrades.go

@@ -232,22 +232,67 @@ func (f following) SourceMoved(ctx context.Context, m link.SourceMoved) error {
 	if err != nil {
 		return notNow(err)
 	}
-	var moved []inventory.Entry
+	read, err := inv.ReadRepositories(ctx)
+	if err != nil {
+		return notNow(err)
+	}
+
+	// Two kinds of module are affected by one merge, and they are affected differently.
+	//
+	// A module **built from** this repository and branch has moved: the mesh records the new commit
+	// as what its source now has, and only what the merge actually changed is rebuilt. A module that
+	// only **packages source from** it has not moved — its own source is somewhere else, at the
+	// commit it already records — so it is rebuilt and its record left alone. Writing this commit as
+	// its source would make it permanently behind a repository its manifest does not come from.
+	var from, packaging []inventory.Entry
+	already := 0
 	for _, e := range entries {
-		if !sourceIs(e.Source, m) {
-			continue
+		switch {
+		case sourceIs(e.Source, m):
+			if e.Source.BuiltFrom == m.Commit {
+				already++
+				continue
+			}
+			// **A merge older than the last look at the source is history, not a move.** The forge
+			// announces what it finds merged, and an old merge surfacing late would otherwise move
+			// the recorded head backwards and rebuild everything built from that repository, once
+			// per old merge (2026-09-28).
+			if isHistory(m.MergedAt, e.Source.Seen) {
+				continue
+			}
+			from = append(from, e)
+		case readsFrom(read[e.Manifest.Module], m):
+			packaging = append(packaging, e)
 		}
-		if e.Source.BuiltFrom == m.Commit {
-			continue
+	}
+	if len(from) == 0 && len(packaging) == 0 {
+		// "Already built from it" and "nothing reads it" are different facts, and reading the first
+		// as the second sends somebody looking for a broken trigger when the mesh is up to date.
+		if already > 0 {
+			fmt.Printf("%s/%s merged into %s (%.8s); %d module(s) the mesh holds are already built "+
+				"from it\n", m.Owner, m.Repo, m.Base, m.Commit, already)
+			return nil
 		}
+		fmt.Printf("%s/%s merged into %s (%.8s); nothing the mesh holds reads it\n",
+			m.Owner, m.Repo, m.Base, m.Commit)
+		return nil
+	}
+	// The same judgement for the packaging kind, against the newest look at that repository by
+	// anything built from it: they keep no record of it themselves, and a replayed old merge should
+	// not rebuild them either.
+	if isHistory(m.MergedAt, lastLookAt(entries, m)) {
+		packaging = nil
+	}
+	touched := whatTheMergeTouched(from, entries, m)
+	for _, e := range touched {
 		if err := inv.SourceMoved(ctx, e.Manifest.Module, m.Commit); err != nil {
 			return notNow(err)
 		}
-		moved = append(moved, e)
 	}
+	moved := append(append([]inventory.Entry{}, touched...), packaging...)
 	if len(moved) == 0 {
-		fmt.Printf("%s/%s merged into %s (%.8s); nothing the mesh holds is built from it\n",
-			m.Owner, m.Repo, m.Base, m.Commit)
+		fmt.Printf("%s/%s merged into %s (%.8s); it changed nothing any module the mesh holds is "+
+			"built from\n", m.Owner, m.Repo, m.Base, m.Commit)
 		return nil
 	}
 	against, err := inv.BuiltAgainst(ctx)
@@ -261,6 +306,14 @@ func (f following) SourceMoved(ctx context.Context, m link.SourceMoved) error {
 	}
 	fmt.Printf("%s/%s merged into %s (%.8s); building %s\n",
 		m.Owner, m.Repo, m.Base, m.Commit, strings.Join(names, ", "))
+	if len(packaging) > 0 {
+		var also []string
+		for _, e := range packaging {
+			also = append(also, e.Manifest.Module)
+		}
+		fmt.Printf("  %s package source from it, so they are rebuilt and their own source record "+
+			"is left where it is\n", strings.Join(also, ", "))
+	}
 	var failed []string
 	for _, e := range ordered {
 		source := buildSource{Repository: e.Source.Repository, Seat: e.Source.Seat}
@@ -286,16 +339,110 @@ func (f following) SourceMoved(ctx context.Context, m link.SourceMoved) error {
 // An empty recorded ref is the repository's default branch, which is what a merge into the base
 // branch of the forge's default means.
 func sourceIs(s inventory.Source, m link.SourceMoved) bool {
-	want := strings.ToLower(m.Owner + "/" + m.Repo)
-	repo := strings.ToLower(strings.TrimSuffix(s.Repository, ".git"))
-	matches := repo == want || strings.HasSuffix(repo, "/"+want) ||
-		(m.CloneURL != "" && strings.EqualFold(strings.TrimSuffix(s.Repository, ".git"), strings.TrimSuffix(m.CloneURL, ".git")))
-	if !matches {
+	if !sameRepository(s.Repository, m) {
 		return false
 	}
 	return s.Ref == "" || s.Ref == m.Base
 }
 
+// sameRepository is whether a recorded repository is the one a merge names, in either spelling it
+// may have been recorded in: a path on the git seat, or the URL it was cloned from.
+func sameRepository(repository string, m link.SourceMoved) bool {
+	want := strings.ToLower(m.Owner + "/" + m.Repo)
+	repo := strings.ToLower(strings.TrimSuffix(repository, ".git"))
+	return repo == want || strings.HasSuffix(repo, "/"+want) ||
+		(m.CloneURL != "" && repo == strings.ToLower(strings.TrimSuffix(m.CloneURL, ".git")))
+}
+
+// readsFrom is whether a module's build read the repository a merge names: the second repository its
+// recipe packages source from. Its ref must be the branch that moved, or unset — the same rule a
+// module's own source follows.
+func readsFrom(read []inventory.ReadRepository, m link.SourceMoved) bool {
+	for _, r := range read {
+		if sameRepository(r.Repository, m) && (r.Ref == "" || r.Ref == m.Base) {
+			return true
+		}
+	}
+	return false
+}
+
+// lastLookAt is the most recent look at this repository by anything built from it.
+func lastLookAt(entries []inventory.Entry, m link.SourceMoved) time.Time {
+	var newest time.Time
+	for _, e := range entries {
+		if sameRepository(e.Source.Repository, m) && e.Source.Seen.After(newest) {
+			newest = e.Source.Seen
+		}
+	}
+	return newest
+}
+
+// whatTheMergeTouched narrows the modules built from a repository to the ones the merge changed.
+//
+// **A change inside no module's own directory is a change to what they share.** The forge lists the
+// files a merge changed; a module is affected when one of them is inside its own directory, when it
+// is built from the repository's root — everything there is its source — or when some changed file
+// belongs to no module's directory at all, which is how a shared file, a build recipe or a
+// dependency at the root rebuilds everything built from that repository.
+//
+// A change inside *another* module's directory is that module's business and not this one's, even
+// when the mesh does not hold that module: `known` is every module this repository is known to hold,
+// whatever branch it was registered from. That is also the limit of this — a repository whose shared
+// code sits inside a directory the mesh has never seen a module in reads as shared, and everything
+// is rebuilt. Rebuilding too much is the safe direction: the fault this whole path exists for is a
+// mesh that believes it is current and is not (novox/hq 04-ISSUES/131).
+func whatTheMergeTouched(candidates, known []inventory.Entry, m link.SourceMoved) []inventory.Entry {
+	// Nothing said about the files, or not all of them said: everything built from it is affected.
+	if len(m.Paths) == 0 || m.PathsTruncated {
+		return candidates
+	}
+	var dirs []string
+	for _, e := range known {
+		if e.Source.Path != "" && sameRepository(e.Source.Repository, m) {
+			dirs = append(dirs, e.Source.Path)
+		}
+	}
+	for _, p := range m.Paths {
+		if !insideAny(p, dirs) {
+			return candidates
+		}
+	}
+	var out []inventory.Entry
+	for _, e := range candidates {
+		if e.Source.Path == "" || anyInside(m.Paths, e.Source.Path) {
+			out = append(out, e)
+		}
+	}
+	return out
+}
+
+// inside is whether a changed file is in a directory: that directory itself, or under it.
+func inside(path, dir string) bool {
+	dir = strings.Trim(dir, "/")
+	path = strings.TrimPrefix(path, "/")
+	return path == dir || strings.HasPrefix(path, dir+"/")
+}
+
+// insideAny is whether a changed file is in any of these directories.
+func insideAny(path string, dirs []string) bool {
+	for _, dir := range dirs {
+		if inside(path, dir) {
+			return true
+		}
+	}
+	return false
+}
+
+// anyInside is whether any of these changed files is in a directory.
+func anyInside(paths []string, dir string) bool {
+	for _, p := range paths {
+		if inside(p, dir) {
+			return true
+		}
+	}
+	return false
+}
+
 // orderByBases is the entries with every base before what stands on it: a module whose build stood
 // on another's artifact comes after that module. Entries outside the set are not waited for — they
 // are not being rebuilt. Stable for what has no order between it.
@@ -362,3 +509,16 @@ func standsOnModule(e inventory.Entry, module string, against map[string][]strin
 	}
 	return false
 }
+
+// isHistory is whether a merge made at mergedAt predates the last time the source was seen. A merge
+// with no time on it is taken as news: refusing it would silence a forge that says less.
+func isHistory(mergedAt string, seen time.Time) bool {
+	if mergedAt == "" || seen.IsZero() {
+		return false
+	}
+	at, err := time.Parse(time.RFC3339, mergedAt)
+	if err != nil {
+		return false
+	}
+	return at.Before(seen)
+}

internal/broker/broker.go

@@ -66,6 +66,19 @@ func FromEnvironment() (Broker, error) {
 	if err != nil {
 		return Broker{}, err
 	}
+	// **One bus, one address** (novox/hq ADR 0131). Everything the mesh hands out — a token, a
+	// machine's membership, a person's credential — must name the bus the control plane itself is
+	// connected to; the setting above predates the move and, on a mesh that has moved, still names
+	// the broker it moved from. The first person issued after the move was handed the retired
+	// broker's port and could not connect to anything (2026-09-28).
+	//
+	// Read from the credential rather than from a second setting somebody keeps in step: the
+	// control plane cannot be wrong about where it is connected.
+	if bus, on, err := OnNATS(); err == nil && on {
+		if where := strings.TrimPrefix(BareAddress(bus), "nats://"); where != "" {
+			address = where
+		}
+	}
 	return Broker{Address: address, Fingerprint: fingerprint}, nil
 }
 

internal/broker/nats.go

@@ -181,6 +181,11 @@ func PermissionsFor(p Principal) (Permissions, error) {
 		for _, seat := range meshSeatsTheControllerUses {
 			pub = append(pub, "mesh.seat."+seat+".accept.>")
 		}
+		// Every module's tools: **the control plane is the way in** (novox/hq ADR 0095). A person
+		// or an agent asks through it and every question passes one process where an audit
+		// belongs — so it, alone among principals, may call any tool by name. The first `ask` on
+		// the new bus was refused the publish (2026-09-28).
+		pub = append(pub, "mesh.mod.*.tool.>")
 
 		// The two events it reacts to, and its ack subject on the stream they arrive from
 		// (streams.go). **Each named, not a pattern**: `mesh.mod.*.event.>` would make the
@@ -292,11 +297,18 @@ func PermissionsFor(p Principal) (Permissions, error) {
 			}
 		}
 
+		// 2c. Its own consumer, which it **pulls**: the runtime asks for the next message and is
+		//     answered on its own inbox, so what it needs is to ask about the consumer and to ask it
+		//     for messages — its own consumer's name, and no other's. Pulled rather than pushed
+		//     because that is the one shape a runtime's client binds without creating anything; the
+		//     controller and the hosts are pushed to. Named here rather than through ConsumerFor,
+		//     which asks for these permissions to build the consumer and would ask forever. A
+		//     subject for a consumer that turns out not to exist grants nothing anybody can use.
+		pub = append(pub,
+			"$JS.API.CONSUMER.INFO."+consumerStream(p)+"."+consumerDurable(p),
+			"$JS.API.CONSUMER.MSG.NEXT."+consumerStream(p)+"."+consumerDurable(p))
+
 		// 3. Seats it holds: full participation.
-		// Its consumer's name, not ConsumerFor: that asks for these permissions to build the
-		// consumer, and would ask forever. A subject for a consumer that turns out not to exist
-		// grants nothing anybody can use.
-		sub = append(sub, "_DELIVER."+consumerDurable(p))
 		for _, s := range p.Holds {
 			// Taking work from the role's queue: the worker consumer it binds (asked about,
 			// delivered on, acknowledged), each on the seat's own stream. The first machine to

internal/broker/nats_test.go

@@ -338,3 +338,24 @@ func admits(pattern, subject []string) bool {
 	}
 	return len(pattern) == len(subject)
 }
+
+// A module pulls its own consumer — asks about it, asks it for messages — and no other module's.
+func TestAModulePullsItsOwnConsumerAndNoOthers(t *testing.T) {
+	p, _ := PermissionsFor(Principal{Kind: KindModule, Node: "one", Module: "audit",
+		Consumes: []string{"shop.order.placed"}, PasswordHash: "x"})
+	for _, want := range []string{"$JS.API.CONSUMER.INFO.EVENTS.one_audit", "$JS.API.CONSUMER.MSG.NEXT.EVENTS.one_audit"} {
+		if !slices.Contains(p.Publish, want) {
+			t.Errorf("a module cannot bind its own consumer: %v lacks %s", p.Publish, want)
+		}
+	}
+	for _, s := range p.Publish {
+		if strings.Contains(s, "CONSUMER.") && !strings.HasSuffix(s, ".one_audit") {
+			t.Errorf("a module may reach another consumer: %s", s)
+		}
+	}
+	for _, s := range p.Subscribe {
+		if strings.HasPrefix(s, "_DELIVER.") {
+			t.Errorf("a module is granted a push delivery it never binds: %s", s)
+		}
+	}
+}

internal/broker/testdata/composed.conf

@@ -24,7 +24,7 @@ accounts {
     jetstream: enabled
     users = [
       { user: "controller", password: "$2a$11$cccccccccccccccccccccc", permissions: {
-        publish: { allow: ["$JS.ACK.CONTROL.controller.>", "$JS.ACK.EVENTS.controller.>", "$JS.API.>", "_INBOX.enrol.>", "mesh.control.>", "mesh.node.>", "mesh.seat.mesh-build-machine.accept.>"] }
+        publish: { allow: ["$JS.ACK.CONTROL.controller.>", "$JS.ACK.EVENTS.controller.>", "$JS.API.>", "_INBOX.enrol.>", "mesh.control.>", "mesh.mod.*.tool.>", "mesh.node.>", "mesh.seat.mesh-build-machine.accept.>"] }
         subscribe: { allow: ["$JS.API.>", "_DELIVER.controller", "_DELIVER.controller.>", "_INBOX.controller.>", "mesh.control.>", "mesh.mod.gitea.event.pull.merged", "mesh.mod.mesh-catalog.event.catching-up", "mesh.mod.mesh-catalog.event.upgraded", "mesh.seat.mesh-build-machine.event.built"] }
         allow_responses: { max: 1, ttl: "1m" }
       } }
@@ -37,18 +37,18 @@ accounts {
         subscribe: { allow: ["_DELIVER.one", "_INBOX.node.one.>", "mesh.node.one.declare"] }
       } }
       { user: "one.telegram", password: "$2a$11$tttttttttttttttttttttt", permissions: {
-        publish: { allow: ["$JS.ACK.EVENTS.one_telegram.>", "$JS.ACK.SEAT_TELEGRAM_SENDER.SEAT_TELEGRAM_SENDER_worker.>", "$JS.API.CONSUMER.INFO.SEAT_TELEGRAM_SENDER.SEAT_TELEGRAM_SENDER_worker", "mesh.seat.telegram-sender.event.delivered", "mesh.seat.telegram-sender.event.failed"] }
-        subscribe: { allow: ["_DELIVER.SEAT_TELEGRAM_SENDER_worker", "_DELIVER.one_telegram", "_INBOX.one.telegram.>", "mesh.mod.telegram.tool.>", "mesh.seat.telegram-sender.accept.send"] }
+        publish: { allow: ["$JS.ACK.EVENTS.one_telegram.>", "$JS.ACK.SEAT_TELEGRAM_SENDER.SEAT_TELEGRAM_SENDER_worker.>", "$JS.API.CONSUMER.INFO.EVENTS.one_telegram", "$JS.API.CONSUMER.INFO.SEAT_TELEGRAM_SENDER.SEAT_TELEGRAM_SENDER_worker", "$JS.API.CONSUMER.MSG.NEXT.EVENTS.one_telegram", "mesh.seat.telegram-sender.event.delivered", "mesh.seat.telegram-sender.event.failed"] }
+        subscribe: { allow: ["_DELIVER.SEAT_TELEGRAM_SENDER_worker", "_INBOX.one.telegram.>", "mesh.mod.telegram.tool.>", "mesh.seat.telegram-sender.accept.send"] }
         allow_responses: { max: 1, ttl: "1m" }
       } }
       { user: "two.audit", password: "$2a$11$aaaaaaaaaaaaaaaaaaaaaa", permissions: {
-        publish: { allow: ["$JS.ACK.EVENTS.two_audit.>"] }
-        subscribe: { allow: ["_DELIVER.two_audit", "_INBOX.two.audit.>", "mesh.mod.audit.tool.>", "mesh.mod.shop.event.order.placed"] }
+        publish: { allow: ["$JS.ACK.EVENTS.two_audit.>", "$JS.API.CONSUMER.INFO.EVENTS.two_audit", "$JS.API.CONSUMER.MSG.NEXT.EVENTS.two_audit"] }
+        subscribe: { allow: ["_INBOX.two.audit.>", "mesh.mod.audit.tool.>", "mesh.mod.shop.event.order.placed"] }
         allow_responses: { max: 1, ttl: "1m" }
       } }
       { user: "two.shop", password: "$2a$11$ssssssssssssssssssssss", permissions: {
-        publish: { allow: ["$JS.ACK.EVENTS.two_shop.>", "mesh.mod.shop.event.order.placed", "mesh.seat.telegram-sender.accept.send"] }
-        subscribe: { allow: ["_DELIVER.two_shop", "_INBOX.two.shop.>", "mesh.mod.shop.tool.>"] }
+        publish: { allow: ["$JS.ACK.EVENTS.two_shop.>", "$JS.API.CONSUMER.INFO.EVENTS.two_shop", "$JS.API.CONSUMER.MSG.NEXT.EVENTS.two_shop", "mesh.mod.shop.event.order.placed", "mesh.seat.telegram-sender.accept.send"] }
+        subscribe: { allow: ["_INBOX.two.shop.>", "mesh.mod.shop.tool.>"] }
         allow_responses: { max: 1, ttl: "1m" }
       } }
     ]

internal/builder/builder.go

@@ -61,6 +61,12 @@ type Result struct {
 	Commit string
 	// Built is each artifact, for reporting.
 	Built []catalogue.Built
+
+	// Read is every repository this build read source from besides the module's own — the second
+	// repository an artifact's recipe names (ArtifactContext). Reported because the manifest the
+	// mesh keeps carries no build section, so nothing else could say that a merge there is a
+	// change to this module (novox/hq 04-ISSUES/131).
+	Read []catalogue.ArtifactContext
 }
 
 // GitCredential is the forge credential a clone may present when the server asks for one.
@@ -220,7 +226,7 @@ func Build(ctx context.Context, run Runner, publish Publisher,
 	}
 	say("done", "%s at %s — %d artifact(s) pinned", manifest.Module, short(commit), len(built))
 	return Result{Manifest: resolved, Commit: commit, Built: built,
-		Against: against(within, manifest, stoodOn)}, nil
+		Against: against(within, manifest, stoodOn), Read: readBy(manifest)}, nil
 }
 
 // Log is where a build says what it is doing, step by step. Nil is silent — the tests pass none,
@@ -1016,3 +1022,31 @@ func instructions(recipe string) []string {
 	flush()
 	return out
 }
+
+// readBy is every repository other than the module's own that this build's recipes read source from,
+// each once and in a fixed order, so two builds of one commit report the same thing the same way.
+func readBy(manifest catalogue.Manifest) []catalogue.ArtifactContext {
+	if manifest.Build == nil {
+		return nil
+	}
+	seen := map[string]bool{}
+	var out []catalogue.ArtifactContext
+	for _, a := range manifest.Build.Artifacts {
+		if a.Context == nil || a.Context.Repository == "" {
+			continue
+		}
+		key := a.Context.Repository + "#" + a.Context.Ref
+		if seen[key] {
+			continue
+		}
+		seen[key] = true
+		out = append(out, *a.Context)
+	}
+	sort.Slice(out, func(i, j int) bool {
+		if out[i].Repository != out[j].Repository {
+			return out[i].Repository < out[j].Repository
+		}
+		return out[i].Ref < out[j].Ref
+	})
+	return out
+}

internal/builder/mirror.go

@@ -180,6 +180,20 @@ func (r Registry) MirrorImage(ctx context.Context, from, repository string) (str
 	if err != nil {
 		return "", err
 	}
+	// **Already held is already mirrored.** A base is named by digest, and a digest this registry
+	// holds under the module's repository is the same bytes whatever upstream would say — so
+	// upstream is not asked. Asked every build, the public hub's anonymous pull limit was reached
+	// on the first merge that rebuilt a whole catalogue (2026-09-28), and every module whose base
+	// lives there failed on a copy it did not need.
+	if strings.HasPrefix(where.reference, "sha256:") {
+		held, err := r.has(ctx, "http://"+r.Address+"/v2/"+repository+"/manifests/"+where.reference)
+		if err != nil {
+			return "", fmt.Errorf("asking %s whether it holds %s: %w", r.Address, from, err)
+		}
+		if held {
+			return r.Address + "/" + repository + "@" + where.reference, nil
+		}
+	}
 	src := &source{client: r.client()}
 	digest, err := r.copyManifest(ctx, src, where, where.reference, repository)
 	if err != nil {

internal/builder/mirror_test.go

@@ -103,6 +103,12 @@ func (m *theMeshsRegistry) handler() http.Handler {
 		m.mu.Lock()
 		defer m.mu.Unlock()
 		switch {
+		case r.Method == http.MethodHead && strings.Contains(r.URL.Path, "/manifests/"):
+			if _, ok := m.manifests[r.URL.Path[strings.LastIndex(r.URL.Path, "/")+1:]]; ok {
+				w.WriteHeader(http.StatusOK)
+			} else {
+				w.WriteHeader(http.StatusNotFound)
+			}
 		case r.Method == http.MethodHead && strings.Contains(r.URL.Path, "/blobs/"):
 			if _, ok := m.blobs[r.URL.Path[strings.LastIndex(r.URL.Path, "/")+1:]]; ok {
 				w.WriteHeader(http.StatusOK)
@@ -219,3 +225,27 @@ func TestATagBeforeTheDigestIsNotPartOfTheRepository(t *testing.T) {
 		t.Fatalf("got %+v", got)
 	}
 }
+
+// A base this registry already holds by digest is not asked of upstream at all: the public hub
+// limits anonymous pulls, and a catalogue rebuilt on one merge asked it once per module.
+func TestABaseAlreadyHeldIsNotAskedOfUpstream(t *testing.T) {
+	src, indexDigest, _ := anUpstreamRegistry(t)
+	dst := &theMeshsRegistry{blobs: map[string][]byte{}, manifests: map[string][]byte{}}
+	dstServer := httptest.NewServer(dst.handler())
+	defer dstServer.Close()
+	address := strings.TrimPrefix(dstServer.URL, "http://")
+	r := Registry{Address: address, HTTP: src.Client()}
+	host := strings.TrimPrefix(src.URL, "http://")
+	if _, err := r.MirrorImage(context.Background(), host+"/library/thing:latest", "hello-web/server"); err != nil {
+		t.Fatal(err)
+	}
+	// Upstream gone: the pinned base is answered from what the mesh holds.
+	src.Close()
+	reference, err := r.MirrorImage(context.Background(), host+"/library/thing@"+indexDigest, "hello-web/server")
+	if err != nil {
+		t.Fatalf("a base the registry holds was asked of an upstream that is gone: %v", err)
+	}
+	if reference != address+"/hello-web/server@"+indexDigest {
+		t.Fatalf("pinned as %q", reference)
+	}
+}

internal/builder/standing_on_test.go

@@ -179,3 +179,24 @@ func TestTheBasesABuildWasHandedAreWhatItStoodOn(t *testing.T) {
 		t.Fatalf("the bases the build was handed were not what it stood on: %v", got)
 	}
 }
+
+// What a build read besides its module's own repository is the second repository its recipes name,
+// each once: a module that packages source living elsewhere is affected when that source moves.
+func TestWhatABuildReadIsTheRepositoriesItsRecipesName(t *testing.T) {
+	elsewhere := catalogue.ArtifactContext{Repository: "http://forge.internal:20000/novox/mesh-controller.git", Ref: "main"}
+	manifest := catalogue.Manifest{
+		Module: "builder",
+		Build: &catalogue.Build{Artifacts: []catalogue.Artifact{
+			{Name: "server", Kind: catalogue.ArtifactImage, From: "Dockerfile", Context: &elsewhere},
+			{Name: "tools", Kind: catalogue.ArtifactImage, From: "Dockerfile", Context: &elsewhere},
+			{Name: "config", Kind: catalogue.ArtifactArchive, From: "etc"},
+		}},
+	}
+	read := readBy(manifest)
+	if len(read) != 1 || read[0] != elsewhere {
+		t.Fatalf("the repositories this build read are %+v", read)
+	}
+	if readBy(catalogue.Manifest{Module: "gitea", Build: &catalogue.Build{}}) != nil {
+		t.Fatal("a module whose recipes name no other repository read one")
+	}
+}

internal/catalogue/declaration.go

@@ -623,6 +623,9 @@ func (r Resolution) compose(with Rendering, owner map[string]string) ([]map[stri
 		// one of them as its environment without saying so (ADR 0086, issue 041).
 		secretFiles := secretFilesOf(resources)
 
+		// Which of this module's resources its preparation runs before, if it prepares anything.
+		prepareBefore := preparationTarget(m)
+
 		for _, unsettled := range resources {
 			resource, err := ApplySettings(unsettled, with.Settings[m.Module])
 			if err != nil {
@@ -708,6 +711,18 @@ func (r Resolution) compose(with Rendering, owner map[string]string) ([]map[stri
 			if renamed := reflectsRenamed(m.Module, resource["reload-on"]); renamed != nil {
 				copied["reload-on"] = renamed
 			}
+			// **A version prepares its state before it runs** (novox/hq ADR 0135). Derived from the
+			// module's own resource rather than declared beside it: what prepares the state is the
+			// module's own code, so what it is given has to be what that code is given — and a
+			// second resource written by hand is a second copy to drift from the first. Placed
+			// immediately before it, because a run-once step stops everything the declaration
+			// places after it (ADR 0052), which is how a version whose preparation failed does not
+			// serve.
+			if prepareBefore != "" && fmt.Sprint(resource["id"]) == prepareBefore {
+				step := prepared(copied)
+				owner[fmt.Sprint(step["id"])] = m.Module
+				out = append(out, step)
+			}
 			owner[fmt.Sprint(copied["id"])] = m.Module
 			out = append(out, copied)
 		}
@@ -1610,3 +1625,73 @@ func atMachinePort(serves map[string]any, module string, ports map[string]map[in
 func AtPublishedPort(values map[string]any, module string, published map[int]int) map[string]any {
 	return atMachinePort(values, module, map[string]map[int]int{module: published})
 }
+
+// PreparationArgument is how the mesh asks a module to prepare its state: one word, to the module's
+// own program, whatever that program is (novox/hq ADR 0135).
+//
+// **One word for every kind of module.** A module built as a Go binary receives it as its argument;
+// one built as a bundle receives it through the runtime, whose entry takes the same word. So the
+// mesh has one way of asking and a module has one way of answering, and neither learns the other's
+// shape.
+const PreparationArgument = "prepare"
+
+// preparationTarget is the resource a module's preparation runs before: its own workload.
+//
+// The first container carrying an artifact this module built, and not itself a step — that is the
+// thing that runs the module's code, and therefore the thing whose state must be ready. Empty when
+// the module prepares nothing, or when nothing it declares could run its code.
+//
+// **A module with two own workloads gates the first of them.** Five modules in the catalogue declare
+// more than one container of their own, none of them preparing anything today. If one ever does and
+// its second workload shares the state, the gate is in front of the first — stated here because the
+// alternative is a field asking an author to restate what the mesh can see.
+func preparationTarget(m Manifest) string {
+	if !m.Prepares {
+		return ""
+	}
+	for _, r := range m.Resources {
+		if fmt.Sprint(r["type"]) != "container" || !ownArtifact(r, m.Module) {
+			continue
+		}
+		if once, _ := r["run-once"].(bool); once {
+			continue
+		}
+		return fmt.Sprint(r["id"])
+	}
+	return ""
+}
+
+// ownArtifact is whether a resource runs something this module built, in either spelling a manifest
+// may be in: naming the artifact, before a build resolved it, or carrying the reference a build
+// recorded — this mesh's own store, under this module's name.
+func ownArtifact(resource map[string]any, module string) bool {
+	if named, _ := resource["artifact"].(string); named != "" {
+		return true
+	}
+	image, _ := resource["image"].(string)
+	return strings.HasPrefix(image, ArtifactStoreScheme+module+"/")
+}
+
+// prepared is the module's own resource as the step that prepares its state: the same image, the same
+// context, run to completion with the mesh's preparation argument.
+//
+// Three things are taken away rather than copied, each because the step runs while the version it
+// prepares for is still running. A published port cannot be bound twice, and a step that tried would
+// fail for a reason that has nothing to do with the state. A fixed address cannot be held twice, for
+// the same reason. And a cadence is what a step is the opposite of: a container runs once and gates,
+// or on a schedule, or stays up, never two (ADR 0053).
+func prepared(from map[string]any) map[string]any {
+	step := map[string]any{}
+	for k, v := range from {
+		step[k] = v
+	}
+	step["id"] = fmt.Sprint(from["id"]) + ".prepare"
+	step["name"] = fmt.Sprint(from["name"]) + "-prepare"
+	step["run-once"] = true
+	step["args"] = []any{PreparationArgument}
+	delete(step, "ports")
+	delete(step, "ip")
+	delete(step, "schedule")
+	delete(step, "reload-on")
+	return step
+}

internal/catalogue/manifest.go

@@ -225,6 +225,19 @@ type Manifest struct {
 	// subscription to the queue it writes to (design 29 §2).
 	Uses []string `json:"uses,omitempty"`
 
+	// Prepares says this module has state that must be brought to the shape this version needs
+	// before this version runs, and that the module's own code does it (novox/hq ADR 0135).
+	//
+	// **A word, not an arrangement.** The mesh runs the module's own program in its preparation
+	// mode, in the module's own context — every binding, credential and setting its code receives,
+	// because it *is* its code. Nothing here names a container, a command, a mount or a variable:
+	// the module already said all of that once, and a second copy is a second thing to drift.
+	//
+	// **Declared, never inferred.** The control plane cannot read what is inside an artifact, so a
+	// module that ships a migration and does not say this breaks on its first upgrade. That is
+	// stated in the record rather than guarded here, because nothing mechanical can guard it.
+	Prepares bool `json:"prepares,omitempty"`
+
 	// Tools are the tools this module answers — request and reply, awaited.
 	//
 	// **New, and not `serves`**, which this manifest already uses for the facts a consumer needs
@@ -1276,6 +1289,17 @@ func ParseManifest(raw []byte) (Manifest, error) {
 				"program that reads what the mesh delivered and reconciles",
 			m.Module, r["id"]))
 	}
+	// **A module that prepares its state must have code the mesh can run** (novox/hq ADR 0135). The
+	// preparation is the module's own program in its preparation mode, so it is derived from the
+	// resource that runs that program — and a module declaring none has asked for something the mesh
+	// cannot compose. Said here, where the manifest is read, rather than by a declaration that
+	// quietly prepares nothing.
+	if m.Prepares && preparationTarget(m) == "" {
+		problems = append(problems, fmt.Sprintf(
+			"%s says it prepares its state, and declares no container running an artifact it built — "+
+				"the preparation is this module's own program, so there has to be one for the mesh to "+
+				"run it in", m.Module))
+	}
 	// **A run-once container is a step the host runs to completion** (novox/hq ADR 0052). It is a
 	// boolean modifier on the container shape — the host runs the container, requires it to exit 0,
 	// and starts whatever the declaration places after it only once it has. A value that is not a

internal/catalogue/prepares_test.go

@@ -0,0 +1,135 @@
+package catalogue
+
+import (
+	"encoding/json"
+	"fmt"
+	"testing"
+)
+
+// A module version prepares its state before it runs (novox/hq ADR 0135).
+//
+// What the mesh derives is the module's own resource, run once with one word, placed immediately in
+// front of the thing it prepares for. What matters in these tests is that the derivation is a copy
+// rather than a second description: the failure it replaces was a hand-written step repeating six
+// fields of the resource it preceded, each free to drift from it.
+
+func aPreparingModule() Manifest {
+	return Manifest{
+		Module:   "gitea",
+		Prepares: true,
+		Resources: []map[string]any{
+			{"id": "state", "type": "directory", "path": "/var/lib/gitea", "mode": "0700"},
+			{"id": "server", "type": "container", "name": "mesh-gitea-server",
+				"image": "gitea/gitea@" + digest, "ports": []any{"3000:3000"}},
+			{"id": "runtime", "type": "container", "name": "mesh-gitea",
+				"image": ArtifactStoreScheme + "gitea/runtime@" + digest, "network": "host",
+				"env":     map[string]any{"MESH_GITEA_STATE_DIR": "/run/state"},
+				"volumes": []any{"/var/lib/gitea:/run/state:ro"},
+				"ports":   []any{"9000:9000"}},
+		},
+	}
+}
+
+func declaredFor(t *testing.T, m Manifest) []map[string]any {
+	t.Helper()
+	// The manifest as the mesh holds it: a build resolved the module's own artifact into the
+	// reference it recorded, which is also how the composition knows whose code a resource runs.
+	out, err := Resolution{Node: "anchor", Modules: []Manifest{m}}.Declaration(
+		Rendering{ArtifactStore: "anchor.internal:5100"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	return out
+}
+
+func idsOf(resources []map[string]any) []string {
+	var ids []string
+	for _, r := range resources {
+		ids = append(ids, fmt.Sprint(r["id"]))
+	}
+	return ids
+}
+
+// The step runs the module's own code, and comes immediately before it — not before the upstream
+// server the module packages, which may be the very thing the state lives in.
+func TestThePreparationRunsTheModulesOwnCodeAndComesRightBeforeIt(t *testing.T) {
+	out := declaredFor(t, aPreparingModule())
+	ids := idsOf(out)
+	at := -1
+	for i, id := range ids {
+		if id == "gitea.runtime.prepare" {
+			at = i
+		}
+	}
+	if at < 0 {
+		t.Fatalf("nothing prepares this module's state: %v", ids)
+	}
+	if ids[at+1] != "gitea.runtime" {
+		t.Fatalf("the preparation is not immediately before the module's own code: %v", ids)
+	}
+	for _, id := range ids[:at] {
+		if id == "gitea.runtime" {
+			t.Fatalf("the module's own code runs before its state is prepared: %v", ids)
+		}
+	}
+}
+
+// It is given exactly what the module's own code is given. Asserted field by field against the
+// resource it was derived from, because writing it twice is the fault this replaces.
+func TestThePreparationIsGivenWhatTheModuleIsGiven(t *testing.T) {
+	out := declaredFor(t, aPreparingModule())
+	declared := byID(out)
+	step, workload := declared["gitea.runtime.prepare"], declared["gitea.runtime"]
+	if step == nil || workload == nil {
+		t.Fatalf("expected both, got %v", idsOf(out))
+	}
+	for _, field := range []string{"image", "network", "env", "volumes", "type"} {
+		if fmt.Sprint(step[field]) != fmt.Sprint(workload[field]) {
+			t.Errorf("the preparation's %s is %v and the module's is %v", field, step[field], workload[field])
+		}
+	}
+	if once, _ := step["run-once"].(bool); !once {
+		t.Error("the preparation is not a step, so nothing waits for it and nothing is gated by it")
+	}
+	if fmt.Sprint(step["args"]) != fmt.Sprint([]any{PreparationArgument}) {
+		t.Errorf("the preparation is asked for as %v", step["args"])
+	}
+	if fmt.Sprint(step["name"]) == fmt.Sprint(workload["name"]) {
+		t.Error("the preparation and the workload have one name, so one removes the other")
+	}
+	// A published port cannot be bound twice, and the version being replaced is still running.
+	if _, published := step["ports"]; published {
+		t.Errorf("the preparation publishes a port the running version holds: %v", step["ports"])
+	}
+}
+
+// A module that says nothing about preparing gets nothing, which is most modules.
+func TestAModuleThatPreparesNothingGetsNoStep(t *testing.T) {
+	m := aPreparingModule()
+	m.Prepares = false
+	for _, id := range idsOf(declaredFor(t, m)) {
+		if id == "gitea.runtime.prepare" {
+			t.Fatal("a module that prepares nothing was given a preparation")
+		}
+	}
+}
+
+// A module whose own code the mesh cannot find has nothing to ask, and saying so where the manifest
+// is read beats a declaration that quietly prepares nothing.
+func TestAModuleThatPreparesAndRunsNoneOfItsOwnCodeIsRefused(t *testing.T) {
+	m := Manifest{
+		Module:   "gitea",
+		Prepares: true,
+		Resources: []map[string]any{
+			// Only the upstream server it packages: nothing here runs gitea's own code.
+			{"id": "server", "type": "container", "name": "mesh-gitea-server", "image": "gitea/gitea@" + digest},
+		},
+	}
+	raw, err := json.Marshal(m)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err := ParseManifest(raw); err == nil {
+		t.Fatal("a module that prepares its state with nothing of its own to run was accepted")
+	}
+}

internal/inventory/builds.go

@@ -36,12 +36,21 @@ type Build struct {
 	// Against is every artifact this build stood on, as references rather than module names —
 	// what makes a build edge derived rather than declared (ADR 0009).
 	Against []string
+	// Read is every repository this build read source from besides the module's own (novox/hq
+	// 04-ISSUES/131), at the ref it read.
+	Read []ReadRepository
 	// Failed is the builder's own words, empty when it worked.
 	Failed string
 	Made   []Artifact
 	At     time.Time
 }
 
+// ReadRepository is a repository a build read source from besides the module's own.
+type ReadRepository struct {
+	Repository string `json:"repository"`
+	Ref        string `json:"ref,omitempty"`
+}
+
 // Artifact is one thing a build published.
 type Artifact struct {
 	Name      string `json:"name"`
@@ -66,17 +75,21 @@ func (i *Inventory) RecordBuild(ctx context.Context, b Build) error {
 	if err != nil {
 		return err
 	}
+	read, err := json.Marshal(b.Read)
+	if err != nil {
+		return err
+	}
 	var module *string
 	if b.Module != "" {
 		module = &b.Module
 	}
 	_, err = i.store.Pool().Exec(ctx,
 		`insert into build (id, repository, ref, module, commit_hash, built_on, failed, made,
-		                    source_path, manifest, built_against)
-		 values ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11)
+		                    source_path, manifest, built_against, built_contexts)
+		 values ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12)
 		 on conflict (id) do nothing`,
 		b.ID, b.Repository, b.Ref, module, b.Commit, b.On, b.Failed, made,
-		b.Path, manifestOrNil(b.Manifest), against)
+		b.Path, manifestOrNil(b.Manifest), against, read)
 	return err
 }
 
@@ -199,6 +212,44 @@ func (i *Inventory) BuiltAgainst(ctx context.Context) (map[string][]string, erro
 	return against, rows.Err()
 }
 
+// ReadRepositories is what each module's newest successful build read source from besides its own
+// repository, by module name.
+//
+// The mirror of BuiltAgainst, and derived the same way and for the same reason: a merge into a
+// repository a module only packages is a change to that module, and the manifest the mesh keeps
+// carries nothing that would say so (novox/hq 04-ISSUES/131).
+func (i *Inventory) ReadRepositories(ctx context.Context) (map[string][]ReadRepository, error) {
+	rows, err := i.store.Pool().Query(ctx,
+		`select distinct on (module) module, built_contexts
+		   from build
+		  where module is not null and module <> '' and failed = ''
+		  order by module, at desc`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	read := map[string][]ReadRepository{}
+	for rows.Next() {
+		var module string
+		var raw []byte
+		if err := rows.Scan(&module, &raw); err != nil {
+			return nil, err
+		}
+		if len(raw) == 0 {
+			continue
+		}
+		var of []ReadRepository
+		if err := json.Unmarshal(raw, &of); err != nil {
+			continue
+		}
+		if len(of) > 0 {
+			read[module] = of
+		}
+	}
+	return read, rows.Err()
+}
+
 // manifestOrNil keeps the difference between "declared nothing" and "predates this being kept".
 //
 // A build recorded before the mesh kept manifests has no manifest, and that is not the same as one

internal/inventory/builds_test.go

@@ -136,3 +136,36 @@ func ids(builds []Build) []string {
 	}
 	return out
 }
+
+// What a build read besides its module's own repository comes back for the newest build of each
+// module, and only for builds that worked. Nothing recorded is absent rather than empty, which is how
+// a build made before the mesh kept this is told from one that read nothing (novox/hq 04-ISSUES/131).
+func TestWhatABuildReadComesBackForTheNewestBuildOfEachModule(t *testing.T) {
+	inv := fresh(t)
+	ctx := context.Background()
+	older := aBuild("older", "builder", "")
+	older.Read = []ReadRepository{{Repository: "novox/mesh-controller", Ref: "release"}}
+	newer := aBuild("newer", "builder", "")
+	newer.Read = []ReadRepository{{Repository: "novox/mesh-controller", Ref: "main"}}
+	plain := aBuild("plain", "gitea", "")
+	failed := aBuild("failed", "route-proxy", "cannot clone")
+	failed.Read = []ReadRepository{{Repository: "novox/mesh-controller", Ref: "main"}}
+	for _, b := range []Build{older, newer, plain, failed} {
+		if err := inv.RecordBuild(ctx, b); err != nil {
+			t.Fatal(err)
+		}
+	}
+	read, err := inv.ReadRepositories(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(read["builder"]) != 1 || read["builder"][0].Ref != "main" {
+		t.Fatalf("the newest build's reading is %+v", read["builder"])
+	}
+	if _, has := read["gitea"]; has {
+		t.Fatalf("a build that read nothing but its own repository reads as %+v", read["gitea"])
+	}
+	if _, has := read["route-proxy"]; has {
+		t.Fatal("a failed build's reading was kept as what that module reads")
+	}
+}

internal/inventory/busrecords_test.go

@@ -86,9 +86,11 @@ func TestAnAssignedModuleBecomesAUserWithWhatItDeclared(t *testing.T) {
 		if err != nil {
 			t.Fatal(err)
 		}
+		// Its tools are every one under its own name — the list in the manifest is a person's
+		// vocabulary for asking, not the module's permission to answer.
 		if !granted(perms.Publish, "mesh.mod.shop.event.order.placed") ||
 			!granted(perms.Publish, "mesh.seat.telegram-sender.accept.send") ||
-			!granted(perms.Subscribe, "mesh.mod.shop.tool.price") {
+			!granted(perms.Subscribe, "mesh.mod.shop.tool.>") {
 			t.Fatalf("one.shop's authority is not what it declared: %+v", perms)
 		}
 	}

internal/inventory/catalogue.go

@@ -8,6 +8,7 @@ import (
 	"sort"
 	"strconv"
 	"strings"
+	"time"
 
 	"github.com/jackc/pgx/v5"
 	"github.com/novox/mesh-controller/internal/catalogue"
@@ -38,6 +39,9 @@ type Source struct {
 	BuiltFrom string
 	// Head is the newest commit the source is known to have.
 	Head string
+	// Seen is when the source was last looked at — by a build, by hand, or by the forge saying it
+	// moved. What a late report of an older move is judged against.
+	Seen time.Time
 }
 
 // Current reports whether what the mesh holds is what the source last had.
@@ -936,12 +940,13 @@ func (i *Inventory) Catalogued(ctx context.Context) ([]Entry, error) {
 		`select m.name, m.manifest,
 		        coalesce(m.source, ''), m.source_path, m.source_seat, coalesce(m.ref, ''),
 		        coalesce(m.built_from, ''), coalesce(m.source_head, ''),
+		        coalesce(m.source_seen, to_timestamp(0)),
 		        coalesce(array_agg(n.name order by n.name) filter (where n.name is not null), '{}')
 		 from module m
 		 left join assignment a on a.module = m.name
 		 left join node n on n.id = a.node
 		 group by m.name, m.manifest, m.source, m.source_path, m.source_seat, m.ref, m.built_from,
-		          m.source_head
+		          m.source_head, m.source_seen
 		 order by m.name`)
 	if err != nil {
 		return nil, err
@@ -955,9 +960,12 @@ func (i *Inventory) Catalogued(ctx context.Context) ([]Entry, error) {
 		var source Source
 		var on []string
 		if err := rows.Scan(&name, &raw, &source.Repository, &source.Path, &source.Seat, &source.Ref,
-			&source.BuiltFrom, &source.Head, &on); err != nil {
+			&source.BuiltFrom, &source.Head, &source.Seen, &on); err != nil {
 			return nil, err
 		}
+		if source.Seen.Unix() == 0 {
+			source.Seen = time.Time{}
+		}
 		var m catalogue.Manifest
 		if err := json.Unmarshal(raw, &m); err != nil {
 			return nil, err

internal/inventory/migrations/0042-a-build-says-which-repositories-it-read.sql

@@ -0,0 +1,13 @@
+-- A build says which repositories it read, so a merge can find everything it affects.
+--
+-- A module is built from the one repository the mesh records — where its module.json lives — and some
+-- modules' recipes reach into a second for the source they package: the packaging and the source are
+-- allowed to live apart (catalogue's ArtifactContext). That second repository is named in the manifest
+-- the build read, and the manifest the mesh *keeps* carries no build section, so nothing on the mesh
+-- could say that a merge into the other repository is a change to this module at all. Two modules are
+-- built from the control plane's own repository, and neither had ever been rebuilt when it moved
+-- (novox/hq 04-ISSUES/131).
+--
+-- Nullable, like the two derived columns beside it: null is a build recorded before the mesh kept
+-- this, which is not the same as a build that read nothing but its module's own repository.
+alter table build add column built_contexts jsonb;

internal/link/build.go

@@ -88,10 +88,23 @@ type BuildResult struct {
 	// (novox/hq ADR 0009). The catalogue turns these into edges; nothing else need care.
 	Against []string `json:"against,omitempty"`
 
+	// Read is every repository this build read source from besides the module's own. A module whose
+	// recipe packages source that lives elsewhere is affected when that repository moves, and the
+	// manifest the mesh keeps says nothing about it (novox/hq 04-ISSUES/131).
+	Read []ReadRepository `json:"read,omitempty"`
+
 	// Failed is why, when it did.
 	Failed string `json:"failed,omitempty"`
 }
 
+// ReadRepository is a repository a build read source from besides the module's own, at the branch,
+// tag or commit it read. Spelled here as well as in the catalogue and the inventory, for the reason
+// MadeArtifact is: one direction of dependency.
+type ReadRepository struct {
+	Repository string `json:"repository"`
+	Ref        string `json:"ref,omitempty"`
+}
+
 // MadeArtifact is one thing a build produced, as a person would want it reported.
 type MadeArtifact struct {
 	Name      string `json:"name"`

internal/link/events.go

@@ -128,6 +128,18 @@ type SourceMoved struct {
 	Commit   string `json:"merge_commit_sha"`
 	CloneURL string `json:"clone_url"`
 	HTMLURL  string `json:"html_url"`
+	// MergedAt is when the forge merged it, RFC 3339. What decides whether this is news.
+	MergedAt string `json:"merged_at"`
+
+	// Paths are the files the merge changed, from the repository's root. Empty means the forge said
+	// nothing about them, and every module built from the repository is treated as affected.
+	Paths []string `json:"paths,omitempty"`
+
+	// PathsTruncated says the merge changed more files than the forge was asked to list, so Paths is
+	// a beginning rather than the whole change — and again, everything is treated as affected. Said
+	// rather than inferred from a round number, because "this is all of it" and "this is as much as
+	// I asked for" are the difference between rebuilding a module and leaving it stale.
+	PathsTruncated bool `json:"paths_truncated,omitempty"`
 }
 
 type Upgraded struct {

internal/link/receive_nats.go

@@ -154,10 +154,47 @@ func (n *natsInbound) deliver(ctx context.Context, act func(context.Context, Con
 			m.seq = meta.Sequence.Stream
 			m.delivered = meta.NumDelivered
 		}
+		// **Work that outlives the acknowledgement window says so while it runs.**
+		//
+		// The bus waits a fixed time to be told a message was taken, and then hands it to whoever
+		// consumes next — which is right for a consumer that died and wrong for one that is busy.
+		// Acting on a merge builds every module the merge changed: minutes of work against a
+		// thirty-second window. So the same merge was handed over again while the first build was
+		// still running, and again after that — on 2026-09-28 one merge ran the mesh's whole
+		// catalogue five times over and exhausted a public registry's pull limit.
+		//
+		// Here rather than in each handler, because the window belongs to the transport and every
+		// handler would otherwise have to remember it. It changes nothing about a handler that
+		// dies: a message is kept alive only while this goroutine is, so a controller that stops
+		// stops saying so, and the bus redelivers exactly as it should.
+		working := make(chan struct{})
+		defer close(working)
+		go stillWorking(msg, working)
 	}
 	act(ctx, m)
 }
 
+// heartbeatWhileWorking is how often a handler still running tells the bus so — comfortably inside
+// the shortest acknowledgement window the mesh gives any of its consumers.
+const heartbeatWhileWorking = 10 * time.Second
+
+// stillWorking keeps one message alive until the work on it returns.
+//
+// An error is not worth reporting: what the bus does when it is not told is redeliver, which is
+// exactly what happens if this fails, and the handler's own outcome is the thing worth logging.
+func stillWorking(msg *nats.Msg, done <-chan struct{}) {
+	tick := time.NewTicker(heartbeatWhileWorking)
+	defer tick.Stop()
+	for {
+		select {
+		case <-done:
+			return
+		case <-tick.C:
+			_ = msg.InProgress()
+		}
+	}
+}
+
 // kindOfSubject is how this transport's addressing becomes what the mesh calls a message.
 //
 // By subject, which is the only thing the server enforces: a body claiming to be a report does not

internal/link/receive_nats_test.go

@@ -395,3 +395,60 @@ func TestEverySubjectTheControllerFollowsDecodesToAKind(t *testing.T) {
 		t.Error("a subject nobody follows decoded to a kind")
 	}
 }
+
+// **A handler slower than the acknowledgement window is not handed its message again.**
+//
+// The bus waits a fixed time to be told a message was taken and then redelivers, which is right for
+// a consumer that died and wrong for one that is busy. Acting on a merge builds modules — minutes
+// against a thirty-second window — and the same merge was handed over five times while the first
+// build was still running (2026-09-28). Here the window is two seconds and the work takes six.
+func TestNatsWorkSlowerThanTheWindowIsNotHandedOverAgain(t *testing.T) {
+	js := aBus(t)
+	// The controller's own consumer, with a window short enough to outlive in a test.
+	if err := js.EnsureConsumer(broker.Consumer{
+		Name: broker.ControllerName, Stream: "CONTROL", Push: true, AckWaitSeconds: 2,
+		Why: "a window short enough to outlive in a test",
+	}); err != nil {
+		t.Fatal(err)
+	}
+	var mu sync.Mutex
+	handled := 0
+	slow := make(chan struct{})
+	s, stop := servingOn(t, js, nil)
+	defer stop()
+	s.listener = slowly{func() {
+		mu.Lock()
+		handled++
+		first := handled == 1
+		mu.Unlock()
+		if first {
+			time.Sleep(6 * time.Second)
+			close(slow)
+		}
+	}}
+
+	body, err := json.Marshal(Report{Node: "anchor", Declared: "d1", Applied: []string{"store"}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err := js.Context().Publish(ReportSubject("anchor"), body); err != nil {
+		t.Fatal(err)
+	}
+	select {
+	case <-slow:
+	case <-time.After(30 * time.Second):
+		t.Fatal("the slow work never finished")
+	}
+	// A moment for a redelivery to arrive, if the bus were going to send one.
+	time.Sleep(3 * time.Second)
+	mu.Lock()
+	defer mu.Unlock()
+	if handled != 1 {
+		t.Fatalf("one report was handled %d times, so slow work is run again while it is running", handled)
+	}
+}
+
+// slowly is a listener that runs whatever it was given.
+type slowly struct{ work func() }
+
+func (s slowly) Heard(context.Context, Report) error { s.work(); return nil }

module.json

@@ -27,6 +27,7 @@
     "bus": "/var/lib/mesh/mesh-controller/bus"
   },
   "secrets-owner": "65534:65534",
+  "prepares": true,
   "resources": [
     {
       "id": "mesh-state",