From 82da252cf027912aeb7ba4f351f7292192cd517f Mon Sep 17 00:00:00 2001
From: jochen <jschoubben@gmail.com>
Date: Mon, 26 Oct 2026 11:23:21 +0100
Subject: [PATCH 1/4] Indexer: index the manifests of modules registered from
 their own repositories, so the grants part has no gap for them

---
 .../cmd/mesh-delivery-indexer/main.go         |  27 +++-
 .../cmd/mesh-delivery-indexer/named.go        |  77 +++++++++++
 .../cmd/mesh-delivery-indexer/named_test.go   |  26 ++++
 .../internal/index/builds.go                  |  49 +++++++
 .../internal/index/candidates.go              |   4 +
 .../internal/index/modules.go                 |   9 +-
 .../internal/index/registered.go              | 126 ++++++++++++++++++
 .../internal/index/registered_test.go         |  97 ++++++++++++++
 .../mesh-delivery-indexer/manifest_test.go    |   4 +-
 modules/mesh-delivery-indexer/module.json     |   3 +-
 10 files changed, 416 insertions(+), 6 deletions(-)
 create mode 100644 modules/mesh-delivery-indexer/internal/index/registered.go
 create mode 100644 modules/mesh-delivery-indexer/internal/index/registered_test.go

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 a4a515f..8081a2f 100644
--- a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/main.go
+++ b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/main.go
@@ -266,11 +266,12 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 		}
 	}
 	errs := make(chan error, 1)
+	var buildsWatch jetstream.KeyWatcher
 	if builds != nil {
 		if w, err := settle(ctx, builds, each); err != nil {
 			process.NotWatched(logger.Printf, delivery.BuildsBucket, err, "a module whose key names no directory is not given one until the indexer starts again")
 		} else {
-			go func() { errs <- follow(ctx, w, each) }()
+			buildsWatch = w
 		}
 	}
 
@@ -285,7 +286,7 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 	}
 	defer calls.Close()
 	ix := &index.Indexer{Store: kvStore{candidates}, Modules: kvStore{modules}, Manifests: kvStore{manifests}, Builds: known, Logf: logger.Printf,
-		Named: namedVia(calls.Call), Trunk: trunkVia(calls.Call), Contains: containsVia(calls.Call)}
+		Named: namedVia(calls.Call), Trunk: trunkVia(calls.Call), Contains: containsVia(calls.Call), Read: readVia(calls.Call)}
 	// 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.
@@ -336,6 +337,28 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 	if err := ix.RecomputeAtStart(ctx); err != nil {
 		logger.Printf("computing the new-form fingerprints at start: %v", err)
 	}
+	// A module registered in the catalogue from its own repository gets its manifest indexed when the controller's records
+	// name it and the bucket holds none (registered.go); the records that follow are heard below.
+	if err := ix.IndexRegisteredAll(ctx); err != nil {
+		logger.Printf("indexing the registered modules at start: %v", err)
+	}
+	if buildsWatch != nil {
+		go func() {
+			errs <- follow(ctx, buildsWatch, func(e jetstream.KeyValueEntry) {
+				each(e)
+				if !opOf(e) {
+					return
+				}
+				var r delivery.BuildRecord
+				if json.Unmarshal(e.Value(), &r) != nil || r.Module == "" {
+					return
+				}
+				if err := ix.IndexRegisteredModule(ctx, r.Module); err != nil {
+					logger.Printf("the registered module %s is not indexed: %v", r.Module, err)
+				}
+			})
+		}()
+	}
 	// The modules the trunk no longer holds go from the bucket (issue 1900); a merge does the same from its own message.
 	if err := ix.Reconcile(ctx); err != nil {
 		logger.Printf("dropping the modules the trunk does not hold at start: %v", err)
diff --git a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named.go b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named.go
index 562c6a9..0678740 100644
--- a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named.go
+++ b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named.go
@@ -2,11 +2,16 @@ package main
 
 import (
 	"context"
+	"crypto/sha256"
+	"encoding/hex"
 	"encoding/json"
 	"fmt"
+	"path"
 	"strings"
 
 	"git.novox.be/novox/mesh-sdk/go/delivery"
+
+	"mesh-delivery-indexer/internal/index"
 )
 
 // commitTreesTool is the forge's tool for a commit's trees (mesh-catalog modules/gitea): with `paths`, by module directory
@@ -93,3 +98,75 @@ func containsVia(call toolCaller) func(ctx context.Context, repository, commit,
 		return *a.Contains, nil
 	}
 }
+
+// getFileTool is the forge's tool for one file at a ref (mesh-catalog modules/gitea gitea_get_file): arguments owner,
+// repo, path and ref, answer {file: {content}}; a path it does not have fails with a 404 in its words.
+const getFileTool = "gitea.gitea_get_file"
+
+// lockFiles are read beside a manifest, as the forge bridge reads them (bridge.LockFiles).
+var lockFiles = []string{"go.sum", "package-lock.json"}
+
+// readVia reads a repository at a commit as the forge bridge does for a merged message: the module directories by
+// gitea_commit_trees, then each one's module.json and lock files by gitea_get_file. A manifest the forge does not have is
+// an error; a lock file it does not have is left out.
+func readVia(call toolCaller) func(ctx context.Context, repository, sha string) (index.RepoRead, error) {
+	return func(_ context.Context, repository, sha string) (index.RepoRead, error) {
+		owner, repo, ok := strings.Cut(delivery.RepositoryName(repository), "/")
+		if !ok {
+			return index.RepoRead{}, fmt.Errorf("%q is not <owner>/<name>", repository)
+		}
+		raw, err := call(commitTreesTool, map[string]any{"owner": owner, "repo": repo, "sha": sha})
+		if err != nil {
+			return index.RepoRead{}, err
+		}
+		var a struct {
+			Root  string            `json:"root"`
+			Trees map[string]string `json:"trees"`
+		}
+		if err := json.Unmarshal(raw, &a); err != nil {
+			return index.RepoRead{}, fmt.Errorf("the answer of %s is not {root, trees}: %w", commitTreesTool, err)
+		}
+		out := index.RepoRead{Root: a.Root, Trees: a.Trees, Manifests: map[string]string{}, Locks: map[string]map[string]string{}}
+		file := func(dir, name string) (string, error) {
+			p := name
+			if dir != "" {
+				p = dir + "/" + name
+			}
+			raw, err := call(getFileTool, map[string]string{"owner": owner, "repo": repo, "path": p, "ref": sha})
+			if err != nil {
+				return "", err
+			}
+			var f struct {
+				File *struct {
+					Content *string `json:"content"`
+				} `json:"file"`
+			}
+			if err := json.Unmarshal(raw, &f); err != nil || f.File == nil || f.File.Content == nil {
+				return "", fmt.Errorf("the answer of %s is not {file: {content}}: %v", getFileTool, err)
+			}
+			return *f.File.Content, nil
+		}
+		for dir := range a.Trees {
+			m, err := file(dir, "module.json")
+			if err != nil {
+				return index.RepoRead{}, fmt.Errorf("%s: %w", path.Join(dir, "module.json"), err)
+			}
+			out.Manifests[dir] = m
+			for _, name := range lockFiles {
+				c, err := file(dir, name)
+				if err != nil {
+					if strings.Contains(err.Error(), ": 404 ") {
+						continue
+					}
+					return index.RepoRead{}, fmt.Errorf("%s: %w", path.Join(dir, name), err)
+				}
+				sum := sha256.Sum256([]byte(c))
+				if out.Locks[dir] == nil {
+					out.Locks[dir] = map[string]string{}
+				}
+				out.Locks[dir][name] = hex.EncodeToString(sum[:])
+			}
+		}
+		return out, nil
+	}
+}
diff --git a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named_test.go b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named_test.go
index 71ace76..2815aae 100644
--- a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named_test.go
+++ b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named_test.go
@@ -3,6 +3,7 @@ package main
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"slices"
 	"strings"
 	"testing"
@@ -50,3 +51,28 @@ func TestTheTrunkIsTheDirectoriesTheForgeListsTrees(t *testing.T) { // 1900/AC3
 		t.Error("the trunk asked for paths")
 	}
 }
+
+func TestReadViaReadsManifestsAndLocks(t *testing.T) {
+	call := func(key string, body any) (json.RawMessage, error) {
+		switch key {
+		case commitTreesTool:
+			return json.RawMessage(`{"root":"r0","trees":{"":"t1"}}`), nil
+		case getFileTool:
+			switch body.(map[string]string)["path"] {
+			case "module.json":
+				return json.RawMessage(`{"file":{"content":"{\"module\":\"snake\"}"}}`), nil
+			case "go.sum":
+				return json.RawMessage(`{"file":{"content":"x"}}`), nil
+			}
+			return nil, errors.New("Gitea API /x: 404 not found")
+		}
+		return nil, errors.New("unexpected " + key)
+	}
+	got, err := readVia(call)(context.Background(), "http://novox.internal:20000/jschoubben/snake.git", "abc")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got.Root != "r0" || got.Manifests[""] != `{"module":"snake"}` || len(got.Locks[""]) != 1 || got.Locks[""]["go.sum"] == "" {
+		t.Fatalf("read = %+v", got)
+	}
+}
diff --git a/modules/mesh-delivery-indexer/internal/index/builds.go b/modules/mesh-delivery-indexer/internal/index/builds.go
index 5dfd681..38376a6 100644
--- a/modules/mesh-delivery-indexer/internal/index/builds.go
+++ b/modules/mesh-delivery-indexer/internal/index/builds.go
@@ -2,6 +2,8 @@ package index
 
 import (
 	"encoding/json"
+	"maps"
+	"slices"
 	"strings"
 	"sync"
 
@@ -88,3 +90,50 @@ func (b *Builds) PathOf(module, repository string) (string, bool) {
 	}
 	return pathOf(strings.Trim(best.Path, "/")), true
 }
+
+// Registration is a module registered in the catalogue from its own repository, as the controller's newest outcome record
+// of it names it: the repository, the directory of its manifest there ("" or "." for the root) and the commit it was
+// built at.
+type Registration struct {
+	Module, Repository, Path, Commit string
+}
+
+// registered is whether the record is an outcome of the trunk (or of no named branch) that did not fail: what registers a
+// module. Unlike IsTrunkBuild it asks for no recorded source inputs, which no build records since ADR 0530 clause 1.
+func registered(r delivery.BuildRecord) bool {
+	return r.State == "" && r.Failed == "" && (r.Ref == "" || r.Ref == "main")
+}
+
+// RegistrationOf is the registration of a module by its newest registering record; false when there is none.
+func (b *Builds) RegistrationOf(module string) (Registration, bool) {
+	var best *delivery.BuildRecord
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	for _, r := range b.records {
+		if r.Module == module && registered(r) && (best == nil || newer(r, *best)) {
+			c := r
+			best = &c
+		}
+	}
+	if best == nil {
+		return Registration{}, false
+	}
+	return Registration{Module: best.Module, Repository: best.Repository, Path: best.Path, Commit: best.Commit}, true
+}
+
+// Registered is the registration of every module a record names, by module name.
+func (b *Builds) Registered() []Registration {
+	b.mu.Lock()
+	names := map[string]bool{}
+	for _, r := range b.records {
+		names[r.Module] = true
+	}
+	b.mu.Unlock()
+	var out []Registration
+	for _, name := range slices.Sorted(maps.Keys(names)) {
+		if reg, ok := b.RegistrationOf(name); ok {
+			out = append(out, reg)
+		}
+	}
+	return out
+}
diff --git a/modules/mesh-delivery-indexer/internal/index/candidates.go b/modules/mesh-delivery-indexer/internal/index/candidates.go
index 7a14378..2cc52d0 100644
--- a/modules/mesh-delivery-indexer/internal/index/candidates.go
+++ b/modules/mesh-delivery-indexer/internal/index/candidates.go
@@ -53,6 +53,9 @@ type Indexer struct {
 	// has none.
 	Named func(ctx context.Context, repository, sha string, paths map[string][]string) (map[string]map[string]string, error)
 	Trunk func(ctx context.Context, repository, sha string) ([]string, error)
+	// Read asks the forge for a repository's module directories at a commit, with their manifests and lock-file hashes, as
+	// the forge bridge reads them for a merged message (registered.go). Nil indexes no registered module.
+	Read func(ctx context.Context, repository, sha string) (RepoRead, error)
 	// Contains says whether a commit is the second or an ancestor of it (gitea.gitea_contains).
 	Contains func(ctx context.Context, repository, commit, in string) (bool, error)
 	Logf     func(format string, args ...any)
@@ -61,6 +64,7 @@ type Indexer struct {
 	source     sourceNow
 	previews   map[string]delivery.Preview              // by previews key (previews.go)
 	toolchains map[string]map[string]delivery.Toolchain // language, then node (toolchains.go)
+	tried      map[string]string                        // registered module to the commit its manifest was last tried at (registered.go)
 	recompute  sync.Mutex                               // one Recompute at a time
 }
 
diff --git a/modules/mesh-delivery-indexer/internal/index/modules.go b/modules/mesh-delivery-indexer/internal/index/modules.go
index 5ff6464..5bd2670 100644
--- a/modules/mesh-delivery-indexer/internal/index/modules.go
+++ b/modules/mesh-delivery-indexer/internal/index/modules.go
@@ -25,6 +25,13 @@ import (
 // A value the module already holds but for its commit is not written again: its commit stays the one its fingerprint first
 // appeared at (writeOverlay), so a merge writes only the modules it changes.
 func (ix *Indexer) applyMerged(ctx context.Context, f delivery.Forge) error {
+	return ix.applyManifests(ctx, f, true)
+}
+
+// applyManifests is applyMerged; drop says whether the modules of the repository the message holds no manifest for are
+// deleted. A message that names only some of a repository's modules (a registered module read on its own, registered.go)
+// drops none.
+func (ix *Indexer) applyManifests(ctx context.Context, f delivery.Forge, drop bool) error {
 	digests, err := ix.keepManifests(ctx, f)
 	if err != nil {
 		return err
@@ -84,7 +91,7 @@ func (ix *Indexer) applyMerged(ctx context.Context, f delivery.Forge) error {
 	}
 	// A module of this repository the merge commit holds no module.json for is gone from the trunk, and so is its key
 	// (issue 1900). A message that carries no manifests (an older writer) or one that cannot be read whole says nothing.
-	if len(f.Manifests) > 0 && every {
+	if drop && len(f.Manifests) > 0 && every {
 		if err := ix.dropRemoved(ctx, f.Repository, held, func(key string, _ delivery.Module) bool { return named[key] }); err != nil {
 			return err
 		}
diff --git a/modules/mesh-delivery-indexer/internal/index/registered.go b/modules/mesh-delivery-indexer/internal/index/registered.go
new file mode 100644
index 0000000..09ddd50
--- /dev/null
+++ b/modules/mesh-delivery-indexer/internal/index/registered.go
@@ -0,0 +1,126 @@
+package index
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// A module registered in the catalogue from its own repository (the operator registers it with the repository and the
+// path of its manifest) had no manifest here: the indexer learns a repository only from a merged message, and no merge
+// followed the registration. The controller's outcome records name each registered module's repository, directory and
+// commit (builds.go Registered), so the indexer reads that module's manifest at the repository's trunk head and writes the
+// same keys a merge writes. A later merge to the repository's trunk reaches the module through the forge bridge's merged
+// message as for every other repository.
+
+// RepoRead is a repository at a commit as the forge bridge reads it for a merged message: the root tree, the tree of each
+// directory holding a module.json (the root spelled ""), their manifests and the hex sha256 of the lock files beside them.
+type RepoRead struct {
+	Root      string
+	Trees     map[string]string
+	Manifests map[string]string
+	Locks     map[string]map[string]string
+}
+
+// IndexRegistered writes the module of a registration as a merge of its repository would, when the modules bucket holds
+// none of that name. Its commit is the head the gate's source names for the repository, else the registration's. The
+// repository's other modules are neither written nor dropped: they are the merges'. A manifest that is not at the path or
+// names another module is said and left.
+func (ix *Indexer) IndexRegistered(ctx context.Context, r Registration) error {
+	if ix.Modules == nil || ix.Read == nil {
+		return nil
+	}
+	key, err := delivery.ModulesKey(r.Module)
+	if err != nil {
+		ix.logf("%s: the registered module has no usable key, skipped: %v", r.Module, err)
+		return nil
+	}
+	if _, _, found, err := ix.Modules.Get(ctx, key); err != nil {
+		return fmt.Errorf("modules.%s: %w", key, err)
+	} else if found {
+		return nil
+	}
+	repository := delivery.RepositoryName(r.Repository)
+	commit := r.Commit
+	ix.mu.Lock()
+	for repo, head := range ix.source.heads {
+		if delivery.SameRepository(repo, r.Repository) && head != "" {
+			commit = head
+		}
+	}
+	ix.mu.Unlock()
+	if repository == "" || commit == "" {
+		ix.logf("%s: registered with no repository or commit, so its manifest is not read", r.Module)
+		return nil
+	}
+	// One try for each commit of a registration: a repository with no manifest where it was registered is said once, not at
+	// every record of the controller's builds.
+	ix.mu.Lock()
+	if ix.tried[r.Module] == commit {
+		ix.mu.Unlock()
+		return nil
+	}
+	if ix.tried == nil {
+		ix.tried = map[string]string{}
+	}
+	ix.tried[r.Module] = commit
+	ix.mu.Unlock()
+	read, err := ix.Read(ctx, repository, commit)
+	if err != nil {
+		ix.mu.Lock()
+		delete(ix.tried, r.Module) // a forge that could not say is asked again
+		ix.mu.Unlock()
+		return fmt.Errorf("%s: reading %s at %s: %w", r.Module, repository, commit, err)
+	}
+	dir := strings.Trim(r.Path, "/")
+	if dir == delivery.RootPath {
+		dir = ""
+	}
+	raw, ok := read.Manifests[dir]
+	if !ok || read.Trees[dir] == "" {
+		ix.logf("%s: %s at %s holds no module.json at %q, so the registered module is not indexed", r.Module, repository, commit, dir)
+		return nil
+	}
+	if name := manifestModule(raw); name != r.Module {
+		ix.logf("%s: the manifest at %q of %s at %s names the module %q, so the registered module is not indexed", r.Module, dir, repository, commit, name)
+		return nil
+	}
+	f := delivery.Forge{V: delivery.Version, Kind: delivery.ForgeMerged, Repository: repository, Merge: commit, Root: read.Root,
+		Trees:     map[string]string{dir: read.Trees[dir]},
+		Manifests: map[string]string{dir: raw}}
+	if l := read.Locks[dir]; len(l) > 0 {
+		f.Locks = map[string]map[string]string{dir: l}
+	}
+	return ix.applyManifests(ctx, f, false)
+}
+
+// IndexRegisteredModule indexes the registration the controller's records name for a module, when there is one.
+func (ix *Indexer) IndexRegisteredModule(ctx context.Context, module string) error {
+	if ix.Builds == nil {
+		return nil
+	}
+	if r, ok := ix.Builds.RegistrationOf(module); ok {
+		return ix.IndexRegistered(ctx, r)
+	}
+	return nil
+}
+
+// IndexRegisteredAll indexes every registered module the modules bucket does not hold. A module that cannot be read is
+// said and the others go on; the first error is answered.
+func (ix *Indexer) IndexRegisteredAll(ctx context.Context) error {
+	if ix.Builds == nil {
+		return nil
+	}
+	var first error
+	for _, r := range ix.Builds.Registered() {
+		if err := ix.IndexRegistered(ctx, r); err != nil {
+			ix.logf("the registered module %s is not indexed: %v", r.Module, err)
+			if first == nil {
+				first = err
+			}
+		}
+	}
+	return first
+}
diff --git a/modules/mesh-delivery-indexer/internal/index/registered_test.go b/modules/mesh-delivery-indexer/internal/index/registered_test.go
new file mode 100644
index 0000000..b5bfae8
--- /dev/null
+++ b/modules/mesh-delivery-indexer/internal/index/registered_test.go
@@ -0,0 +1,97 @@
+package index
+
+import (
+	"context"
+	"errors"
+	"testing"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+func TestARegisteredModuleIsIndexedFromItsRepository(t *testing.T) { // the grants part's gaps: modules registered from their own repositories had no manifest here
+	const forge = "http://novox.internal:20000/jschoubben/snake.git"
+	snake := `{"module":"snake","version":"1"}`
+	for _, tc := range []struct {
+		name  string
+		path  string
+		read  RepoRead
+		err   error
+		held  bool // modules.snake exists already
+		other bool // modules.other of the same repository exists
+		want  bool // modules.snake is written
+	}{
+		{name: "a module at the root of its repository", path: "", want: true,
+			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
+		{name: "a root spelled as a dot", path: ".", want: true,
+			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
+		{name: "a module in a directory", path: "modules/snake", want: true,
+			read: RepoRead{Root: "r0", Trees: map[string]string{"modules/snake": "t1"}, Manifests: map[string]string{"modules/snake": snake}}},
+		{name: "another module of the repository is neither written nor dropped", path: "", want: true, other: true,
+			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
+		{name: "a module the bucket holds is left", path: "", held: true,
+			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
+		{name: "no manifest at the path", path: "modules/x",
+			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
+		{name: "a manifest of another module", path: "",
+			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": `{"module":"other","version":"1"}`}}},
+		{name: "a forge that cannot say", path: "", err: errors.New("down")},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			ix, mods := modulesIndexer(t, rec(t, "build-1", "snake", forge, tc.path, "", "", "2026-10-19T09:00:00Z", ""))
+			if tc.held {
+				if err := mods.Create(context.Background(), "snake", mustModule(t, delivery.Module{Repository: "jschoubben/snake", Commit: h1, Path: ".", None2: "x"})); err != nil {
+					t.Fatal(err)
+				}
+			}
+			if tc.other {
+				if err := mods.Create(context.Background(), "other", mustModule(t, delivery.Module{Repository: "jschoubben/snake", Commit: h1, Path: "modules/other", None2: "x"})); err != nil {
+					t.Fatal(err)
+				}
+			}
+			ix.Manifests = newMem()
+			var asked struct{ repo, sha string }
+			ix.Read = func(_ context.Context, repo, sha string) (RepoRead, error) {
+				asked.repo, asked.sha = repo, sha
+				return tc.read, tc.err
+			}
+			err := ix.IndexRegisteredAll(context.Background())
+			if (err != nil) != (tc.err != nil) {
+				t.Fatalf("error = %v", err)
+			}
+			m, ok := moduleOf(t, mods, "snake")
+			if tc.want {
+				if !ok || m.Manifest == "" || m.Repository != "jschoubben/snake" || m.Commit != "7a74cee83f88e6585a5511c3cc53bdf0f5303d20" || m.Path != pathOf(dirOf(tc.path)) {
+					t.Fatalf("modules.snake = %+v, found %v", m, ok)
+				}
+				if len(ix.Manifests.(*memStore).vals) != 1 {
+					t.Errorf("manifests written = %d, want 1", len(ix.Manifests.(*memStore).vals))
+				}
+				if asked.repo != "jschoubben/snake" {
+					t.Errorf("the forge was asked for %q", asked.repo)
+				}
+			} else if !tc.held && ok {
+				t.Fatalf("modules.snake written: %+v", m)
+			}
+			if _, ok := moduleOf(t, mods, "other"); ok != tc.other {
+				t.Errorf("modules.other held = %v, want %v", ok, tc.other)
+			}
+		})
+	}
+}
+
+
+func mustModule(t *testing.T, m delivery.Module) []byte {
+	t.Helper()
+	b, err := delivery.EncodeModule(withV(m))
+	if err != nil {
+		t.Fatal(err)
+	}
+	return b
+}
+
+func dirOf(p string) string {
+	if p == "." {
+		return ""
+	}
+	return p
+}
diff --git a/modules/mesh-delivery-indexer/manifest_test.go b/modules/mesh-delivery-indexer/manifest_test.go
index b8c3fc5..5822f79 100644
--- a/modules/mesh-delivery-indexer/manifest_test.go
+++ b/modules/mesh-delivery-indexer/manifest_test.go
@@ -95,10 +95,10 @@ func TestManifestDeclarations(t *testing.T) { // 1238/AC1, 1444 (reads the build
 	if m.SecretsOwner != "mesh-delivery-indexer" {
 		t.Errorf("secrets-owner = %q", m.SecretsOwner)
 	}
-	// Two invokes: the forge's trees (the named paths' objects, since the indexer is the one reader of a manifest's paths:
+	// 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{"gitea.gitea_commit_trees", "gitea.gitea_contains"}; !reflect.DeepEqual(m.Invokes, want) {
+	if want := []string{"gitea.gitea_commit_trees", "gitea.gitea_contains", "gitea.gitea_get_file"}; !reflect.DeepEqual(m.Invokes, want) {
 		t.Errorf("invokes = %v, want %v", m.Invokes, want)
 	}
 	// No emits, no streams, no bus, no seat, no tool (ADR 0437 §4).
diff --git a/modules/mesh-delivery-indexer/module.json b/modules/mesh-delivery-indexer/module.json
index bd5a90e..6abdf0e 100644
--- a/modules/mesh-delivery-indexer/module.json
+++ b/modules/mesh-delivery-indexer/module.json
@@ -23,7 +23,8 @@
   ],
   "invokes": [
     "gitea.gitea_commit_trees",
-    "gitea.gitea_contains"
+    "gitea.gitea_contains",
+    "gitea.gitea_get_file"
   ],
   "own-secrets": {
     "broker": "${dir:state}/broker"
-- 
2.54.0


From c44b9f91cd81bb274e612137778ffac02ad381ba Mon Sep 17 00:00:00 2001
From: jochen <jschoubben@gmail.com>
Date: Mon, 26 Oct 2026 11:23:27 +0100
Subject: [PATCH 2/4] Indexer: gofmt

---
 modules/mesh-delivery-indexer/internal/index/registered_test.go | 1 -
 1 file changed, 1 deletion(-)

diff --git a/modules/mesh-delivery-indexer/internal/index/registered_test.go b/modules/mesh-delivery-indexer/internal/index/registered_test.go
index b5bfae8..70e9779 100644
--- a/modules/mesh-delivery-indexer/internal/index/registered_test.go
+++ b/modules/mesh-delivery-indexer/internal/index/registered_test.go
@@ -79,7 +79,6 @@ func TestARegisteredModuleIsIndexedFromItsRepository(t *testing.T) { // the gran
 	}
 }
 
-
 func mustModule(t *testing.T, m delivery.Module) []byte {
 	t.Helper()
 	b, err := delivery.EncodeModule(withV(m))
-- 
2.54.0


From d9bfba1e6253d4f9cdb9d5ef3e934b3450ae948c Mon Sep 17 00:00:00 2001
From: jochen <jschoubben@gmail.com>
Date: Mon, 26 Oct 2026 11:36:22 +0100
Subject: [PATCH 3/4] Indexer: read one directory of a registered module's
 repository, leave a repository the source names to its merges, accept master
 as a trunk

---
 .../cmd/mesh-delivery-indexer/named.go        | 12 ++--
 .../cmd/mesh-delivery-indexer/named_test.go   |  9 ++-
 .../internal/index/builds.go                  |  4 +-
 .../internal/index/candidates.go              |  8 +--
 .../internal/index/registered.go              | 39 +++++++-----
 .../internal/index/registered_test.go         | 62 +++++++++++++------
 6 files changed, 86 insertions(+), 48 deletions(-)

diff --git a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named.go b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named.go
index 0678740..796cfba 100644
--- a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named.go
+++ b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named.go
@@ -106,11 +106,11 @@ const getFileTool = "gitea.gitea_get_file"
 // lockFiles are read beside a manifest, as the forge bridge reads them (bridge.LockFiles).
 var lockFiles = []string{"go.sum", "package-lock.json"}
 
-// readVia reads a repository at a commit as the forge bridge does for a merged message: the module directories by
-// gitea_commit_trees, then each one's module.json and lock files by gitea_get_file. A manifest the forge does not have is
-// an error; a lock file it does not have is left out.
-func readVia(call toolCaller) func(ctx context.Context, repository, sha string) (index.RepoRead, error) {
-	return func(_ context.Context, repository, sha string) (index.RepoRead, error) {
+// readVia reads a repository at a commit as the forge bridge does for a merged message: the trees by gitea_commit_trees,
+// then the module.json and lock files of the one directory dir by gitea_get_file (a repository can hold hundreds). A manifest the
+// forge does not have is an error; a directory with no module.json in the trees is answered with no manifest; a lock file it does not have is left out.
+func readVia(call toolCaller) func(ctx context.Context, repository, sha, dir string) (index.RepoRead, error) {
+	return func(_ context.Context, repository, sha, dir string) (index.RepoRead, error) {
 		owner, repo, ok := strings.Cut(delivery.RepositoryName(repository), "/")
 		if !ok {
 			return index.RepoRead{}, fmt.Errorf("%q is not <owner>/<name>", repository)
@@ -146,7 +146,7 @@ func readVia(call toolCaller) func(ctx context.Context, repository, sha string)
 			}
 			return *f.File.Content, nil
 		}
-		for dir := range a.Trees {
+		if _, held := a.Trees[dir]; held {
 			m, err := file(dir, "module.json")
 			if err != nil {
 				return index.RepoRead{}, fmt.Errorf("%s: %w", path.Join(dir, "module.json"), err)
diff --git a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named_test.go b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named_test.go
index 2815aae..b3040ed 100644
--- a/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named_test.go
+++ b/modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named_test.go
@@ -53,11 +53,13 @@ func TestTheTrunkIsTheDirectoriesTheForgeListsTrees(t *testing.T) { // 1900/AC3
 }
 
 func TestReadViaReadsManifestsAndLocks(t *testing.T) {
+	var files []string
 	call := func(key string, body any) (json.RawMessage, error) {
 		switch key {
 		case commitTreesTool:
-			return json.RawMessage(`{"root":"r0","trees":{"":"t1"}}`), nil
+			return json.RawMessage(`{"root":"r0","trees":{"":"t1","modules/other":"t2"}}`), nil
 		case getFileTool:
+			files = append(files, body.(map[string]string)["path"])
 			switch body.(map[string]string)["path"] {
 			case "module.json":
 				return json.RawMessage(`{"file":{"content":"{\"module\":\"snake\"}"}}`), nil
@@ -68,10 +70,13 @@ func TestReadViaReadsManifestsAndLocks(t *testing.T) {
 		}
 		return nil, errors.New("unexpected " + key)
 	}
-	got, err := readVia(call)(context.Background(), "http://novox.internal:20000/jschoubben/snake.git", "abc")
+	got, err := readVia(call)(context.Background(), "http://novox.internal:20000/jschoubben/snake.git", "abc", "")
 	if err != nil {
 		t.Fatal(err)
 	}
+	if len(got.Manifests) != 1 || len(files) != 3 { // the one directory asked: its manifest and two lock files, never the others
+		t.Fatalf("manifests = %v, files asked = %v", got.Manifests, files)
+	}
 	if got.Root != "r0" || got.Manifests[""] != `{"module":"snake"}` || len(got.Locks[""]) != 1 || got.Locks[""]["go.sum"] == "" {
 		t.Fatalf("read = %+v", got)
 	}
diff --git a/modules/mesh-delivery-indexer/internal/index/builds.go b/modules/mesh-delivery-indexer/internal/index/builds.go
index 38376a6..8656664 100644
--- a/modules/mesh-delivery-indexer/internal/index/builds.go
+++ b/modules/mesh-delivery-indexer/internal/index/builds.go
@@ -98,10 +98,10 @@ type Registration struct {
 	Module, Repository, Path, Commit string
 }
 
-// registered is whether the record is an outcome of the trunk (or of no named branch) that did not fail: what registers a
+// registered is whether the record is an outcome of the trunk (no named branch, or main, master or trunk, as a repository's default branch is named) that did not fail: what registers a
 // module. Unlike IsTrunkBuild it asks for no recorded source inputs, which no build records since ADR 0530 clause 1.
 func registered(r delivery.BuildRecord) bool {
-	return r.State == "" && r.Failed == "" && (r.Ref == "" || r.Ref == "main")
+	return r.State == "" && r.Failed == "" && trunkLike[r.Ref]
 }
 
 // RegistrationOf is the registration of a module by its newest registering record; false when there is none.
diff --git a/modules/mesh-delivery-indexer/internal/index/candidates.go b/modules/mesh-delivery-indexer/internal/index/candidates.go
index 2cc52d0..a40eeb1 100644
--- a/modules/mesh-delivery-indexer/internal/index/candidates.go
+++ b/modules/mesh-delivery-indexer/internal/index/candidates.go
@@ -53,9 +53,9 @@ type Indexer struct {
 	// has none.
 	Named func(ctx context.Context, repository, sha string, paths map[string][]string) (map[string]map[string]string, error)
 	Trunk func(ctx context.Context, repository, sha string) ([]string, error)
-	// Read asks the forge for a repository's module directories at a commit, with their manifests and lock-file hashes, as
-	// the forge bridge reads them for a merged message (registered.go). Nil indexes no registered module.
-	Read func(ctx context.Context, repository, sha string) (RepoRead, error)
+	// Read asks the forge for a repository's trees at a commit and the manifest and lock-file hashes of the one module directory dir (the
+	// root spelled ""), as the forge bridge reads them for a merged message (registered.go). Nil indexes no registered module.
+	Read func(ctx context.Context, repository, sha, dir string) (RepoRead, error)
 	// Contains says whether a commit is the second or an ancestor of it (gitea.gitea_contains).
 	Contains func(ctx context.Context, repository, commit, in string) (bool, error)
 	Logf     func(format string, args ...any)
@@ -64,7 +64,7 @@ type Indexer struct {
 	source     sourceNow
 	previews   map[string]delivery.Preview              // by previews key (previews.go)
 	toolchains map[string]map[string]delivery.Toolchain // language, then node (toolchains.go)
-	tried      map[string]string                        // registered module to the commit its manifest was last tried at (registered.go)
+	tried      map[string]bool                          // repository, commit and directory a registered module's manifest was tried at (registered.go)
 	recompute  sync.Mutex                               // one Recompute at a time
 }
 
diff --git a/modules/mesh-delivery-indexer/internal/index/registered.go b/modules/mesh-delivery-indexer/internal/index/registered.go
index 09ddd50..248bc81 100644
--- a/modules/mesh-delivery-indexer/internal/index/registered.go
+++ b/modules/mesh-delivery-indexer/internal/index/registered.go
@@ -11,7 +11,7 @@ import (
 // A module registered in the catalogue from its own repository (the operator registers it with the repository and the
 // path of its manifest) had no manifest here: the indexer learns a repository only from a merged message, and no merge
 // followed the registration. The controller's outcome records name each registered module's repository, directory and
-// commit (builds.go Registered), so the indexer reads that module's manifest at the repository's trunk head and writes the
+// commit (builds.go Registered), so the indexer reads that module's manifest  writes the
 // same keys a merge writes. A later merge to the repository's trunk reaches the module through the forge bridge's merged
 // message as for every other repository.
 
@@ -25,7 +25,7 @@ type RepoRead struct {
 }
 
 // IndexRegistered writes the module of a registration as a merge of its repository would, when the modules bucket holds
-// none of that name. Its commit is the head the gate's source names for the repository, else the registration's. The
+// none of that name. Its commit is the registration's; a repository the gate's source names is left to the merges. The
 // repository's other modules are neither written nor dropped: they are the merges'. A manifest that is not at the path or
 // names another module is said and left.
 func (ix *Indexer) IndexRegistered(ctx context.Context, r Registration) error {
@@ -44,40 +44,47 @@ func (ix *Indexer) IndexRegistered(ctx context.Context, r Registration) error {
 	}
 	repository := delivery.RepositoryName(r.Repository)
 	commit := r.Commit
+	dir := strings.Trim(r.Path, "/")
+	if dir == delivery.RootPath {
+		dir = ""
+	}
+	// A repository the gate's source names is the merges': an unheld module there was removed by a merge, or its record is
+	// stale, and reading the repository for it would cost a forge call for each such module at every start.
 	ix.mu.Lock()
-	for repo, head := range ix.source.heads {
-		if delivery.SameRepository(repo, r.Repository) && head != "" {
-			commit = head
+	owned := false
+	for repo := range ix.source.heads {
+		if delivery.SameRepository(repo, r.Repository) {
+			owned = true
 		}
 	}
 	ix.mu.Unlock()
+	if owned {
+		return nil
+	}
 	if repository == "" || commit == "" {
 		ix.logf("%s: registered with no repository or commit, so its manifest is not read", r.Module)
 		return nil
 	}
-	// One try for each commit of a registration: a repository with no manifest where it was registered is said once, not at
-	// every record of the controller's builds.
+	// One try for each repository, commit and directory: a repository with no manifest where it was registered is said once,
+	// not at every record of the controller's builds.
+	tried := repository + "@" + commit + ":" + dir
 	ix.mu.Lock()
-	if ix.tried[r.Module] == commit {
+	if ix.tried[tried] {
 		ix.mu.Unlock()
 		return nil
 	}
 	if ix.tried == nil {
-		ix.tried = map[string]string{}
+		ix.tried = map[string]bool{}
 	}
-	ix.tried[r.Module] = commit
+	ix.tried[tried] = true
 	ix.mu.Unlock()
-	read, err := ix.Read(ctx, repository, commit)
+	read, err := ix.Read(ctx, repository, commit, dir)
 	if err != nil {
 		ix.mu.Lock()
-		delete(ix.tried, r.Module) // a forge that could not say is asked again
+		delete(ix.tried, tried) // a forge that could not say is asked again
 		ix.mu.Unlock()
 		return fmt.Errorf("%s: reading %s at %s: %w", r.Module, repository, commit, err)
 	}
-	dir := strings.Trim(r.Path, "/")
-	if dir == delivery.RootPath {
-		dir = ""
-	}
 	raw, ok := read.Manifests[dir]
 	if !ok || read.Trees[dir] == "" {
 		ix.logf("%s: %s at %s holds no module.json at %q, so the registered module is not indexed", r.Module, repository, commit, dir)
diff --git a/modules/mesh-delivery-indexer/internal/index/registered_test.go b/modules/mesh-delivery-indexer/internal/index/registered_test.go
index 70e9779..a6bca70 100644
--- a/modules/mesh-delivery-indexer/internal/index/registered_test.go
+++ b/modules/mesh-delivery-indexer/internal/index/registered_test.go
@@ -12,32 +12,41 @@ func TestARegisteredModuleIsIndexedFromItsRepository(t *testing.T) { // the gran
 	const forge = "http://novox.internal:20000/jschoubben/snake.git"
 	snake := `{"module":"snake","version":"1"}`
 	for _, tc := range []struct {
-		name  string
-		path  string
-		read  RepoRead
-		err   error
-		held  bool // modules.snake exists already
-		other bool // modules.other of the same repository exists
-		want  bool // modules.snake is written
+		name     string
+		path     string
+		read     RepoRead
+		err      error
+		ref      string            // the build record's ref
+		heads    map[string]string // the gate source's heads
+		wantRead bool              // the forge is read
+		held     bool              // modules.snake exists already
+		other    bool              // modules.other of the same repository exists
+		want     bool              // modules.snake is written
 	}{
-		{name: "a module at the root of its repository", path: "", want: true,
+		{wantRead: true, name: "a module at the root of its repository", path: "", want: true,
 			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
-		{name: "a root spelled as a dot", path: ".", want: true,
+		{wantRead: true, name: "a root spelled as a dot", path: ".", want: true,
 			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
-		{name: "a module in a directory", path: "modules/snake", want: true,
+		{wantRead: true, name: "a module in a directory", path: "modules/snake", want: true,
 			read: RepoRead{Root: "r0", Trees: map[string]string{"modules/snake": "t1"}, Manifests: map[string]string{"modules/snake": snake}}},
-		{name: "another module of the repository is neither written nor dropped", path: "", want: true, other: true,
+		{wantRead: true, name: "another module of the repository is neither written nor dropped", path: "", want: true, other: true,
 			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
 		{name: "a module the bucket holds is left", path: "", held: true,
 			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
-		{name: "no manifest at the path", path: "modules/x",
+		{wantRead: true, name: "no manifest at the path", path: "modules/x",
 			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
-		{name: "a manifest of another module", path: "",
+		{wantRead: true, name: "a manifest of another module", path: "",
 			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": `{"module":"other","version":"1"}`}}},
-		{name: "a forge that cannot say", path: "", err: errors.New("down")},
+		{wantRead: true, name: "a repository whose default branch is master", path: "", ref: "master", want: true,
+			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
+		{name: "a record of another branch", path: "", ref: "feat/x",
+			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
+		{name: "a repository the gate's source names is the merges'", path: "", heads: map[string]string{"jschoubben/snake": h2},
+			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
+		{wantRead: true, name: "a forge that cannot say", path: "", err: errors.New("down")},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
-			ix, mods := modulesIndexer(t, rec(t, "build-1", "snake", forge, tc.path, "", "", "2026-10-19T09:00:00Z", ""))
+			ix, mods := modulesIndexer(t, rec(t, "build-1", "snake", forge, tc.path, tc.ref, "", "2026-10-19T09:00:00Z", ""))
 			if tc.held {
 				if err := mods.Create(context.Background(), "snake", mustModule(t, delivery.Module{Repository: "jschoubben/snake", Commit: h1, Path: ".", None2: "x"})); err != nil {
 					t.Fatal(err)
@@ -49,15 +58,32 @@ func TestARegisteredModuleIsIndexedFromItsRepository(t *testing.T) { // the gran
 				}
 			}
 			ix.Manifests = newMem()
-			var asked struct{ repo, sha string }
-			ix.Read = func(_ context.Context, repo, sha string) (RepoRead, error) {
-				asked.repo, asked.sha = repo, sha
+			var asked struct {
+				repo, sha, dir string
+				n              int
+			}
+			ix.Read = func(_ context.Context, repo, sha, dir string) (RepoRead, error) {
+				asked.repo, asked.sha, asked.dir = repo, sha, dir
+				asked.n++
 				return tc.read, tc.err
 			}
+			if tc.heads != nil {
+				ix.source = sourceNow{rev: 1, heads: tc.heads}
+			}
 			err := ix.IndexRegisteredAll(context.Background())
 			if (err != nil) != (tc.err != nil) {
 				t.Fatalf("error = %v", err)
 			}
+			wantReads := 1
+			if !tc.wantRead {
+				wantReads = 0
+			}
+			if tc.wantRead && asked.dir != dirOf(tc.path) {
+				t.Errorf("the forge was asked for directory %q", asked.dir)
+			}
+			if asked.n != wantReads {
+				t.Errorf("forge reads = %d, want %d", asked.n, wantReads)
+			}
 			m, ok := moduleOf(t, mods, "snake")
 			if tc.want {
 				if !ok || m.Manifest == "" || m.Repository != "jschoubben/snake" || m.Commit != "7a74cee83f88e6585a5511c3cc53bdf0f5303d20" || m.Path != pathOf(dirOf(tc.path)) {
-- 
2.54.0


From 646f83642a01f65fe9890ff37fd8bd37038d39c1 Mon Sep 17 00:00:00 2001
From: jochen <jschoubben@gmail.com>
Date: Mon, 26 Oct 2026 11:41:46 +0100
Subject: [PATCH 4/4] Indexer: read a registered module at the source's head
 when it names one, else at the registered commit

---
 .../internal/index/registered.go              | 20 ++++++++-----------
 .../internal/index/registered_test.go         | 11 ++++++++--
 2 files changed, 17 insertions(+), 14 deletions(-)

diff --git a/modules/mesh-delivery-indexer/internal/index/registered.go b/modules/mesh-delivery-indexer/internal/index/registered.go
index 248bc81..2ed1f30 100644
--- a/modules/mesh-delivery-indexer/internal/index/registered.go
+++ b/modules/mesh-delivery-indexer/internal/index/registered.go
@@ -11,8 +11,8 @@ import (
 // A module registered in the catalogue from its own repository (the operator registers it with the repository and the
 // path of its manifest) had no manifest here: the indexer learns a repository only from a merged message, and no merge
 // followed the registration. The controller's outcome records name each registered module's repository, directory and
-// commit (builds.go Registered), so the indexer reads that module's manifest  writes the
-// same keys a merge writes. A later merge to the repository's trunk reaches the module through the forge bridge's merged
+// commit (builds.go Registered), so the indexer reads that module's manifest at the repository's head (the gate's source names it) or, with none named, at the
+// registered commit, and writes the same keys a merge writes. A later merge to the repository's trunk reaches the module through the forge bridge's merged
 // message as for every other repository.
 
 // RepoRead is a repository at a commit as the forge bridge reads it for a merged message: the root tree, the tree of each
@@ -25,7 +25,7 @@ type RepoRead struct {
 }
 
 // IndexRegistered writes the module of a registration as a merge of its repository would, when the modules bucket holds
-// none of that name. Its commit is the registration's; a repository the gate's source names is left to the merges. The
+// none of that name. Its commit is the head the gate's source names for the repository, else the registration's. The
 // repository's other modules are neither written nor dropped: they are the merges'. A manifest that is not at the path or
 // names another module is said and left.
 func (ix *Indexer) IndexRegistered(ctx context.Context, r Registration) error {
@@ -48,19 +48,15 @@ func (ix *Indexer) IndexRegistered(ctx context.Context, r Registration) error {
 	if dir == delivery.RootPath {
 		dir = ""
 	}
-	// A repository the gate's source names is the merges': an unheld module there was removed by a merge, or its record is
-	// stale, and reading the repository for it would cost a forge call for each such module at every start.
+	// The head the gate's source names for the repository, when it names one, else the registration's commit. A module a
+	// merge removed is absent at the head and is said and left.
 	ix.mu.Lock()
-	owned := false
-	for repo := range ix.source.heads {
-		if delivery.SameRepository(repo, r.Repository) {
-			owned = true
+	for repo, head := range ix.source.heads {
+		if delivery.SameRepository(repo, r.Repository) && head != "" {
+			commit = head
 		}
 	}
 	ix.mu.Unlock()
-	if owned {
-		return nil
-	}
 	if repository == "" || commit == "" {
 		ix.logf("%s: registered with no repository or commit, so its manifest is not read", r.Module)
 		return nil
diff --git a/modules/mesh-delivery-indexer/internal/index/registered_test.go b/modules/mesh-delivery-indexer/internal/index/registered_test.go
index a6bca70..9098816 100644
--- a/modules/mesh-delivery-indexer/internal/index/registered_test.go
+++ b/modules/mesh-delivery-indexer/internal/index/registered_test.go
@@ -41,7 +41,7 @@ func TestARegisteredModuleIsIndexedFromItsRepository(t *testing.T) { // the gran
 			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
 		{name: "a record of another branch", path: "", ref: "feat/x",
 			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
-		{name: "a repository the gate's source names is the merges'", path: "", heads: map[string]string{"jschoubben/snake": h2},
+		{wantRead: true, name: "a repository the source names, the module unheld and present at the head", path: "", want: true, heads: map[string]string{"jschoubben/snake": h2},
 			read: RepoRead{Root: "r0", Trees: map[string]string{"": "t1"}, Manifests: map[string]string{"": snake}}},
 		{wantRead: true, name: "a forge that cannot say", path: "", err: errors.New("down")},
 	} {
@@ -74,6 +74,13 @@ func TestARegisteredModuleIsIndexedFromItsRepository(t *testing.T) { // the gran
 			if (err != nil) != (tc.err != nil) {
 				t.Fatalf("error = %v", err)
 			}
+			wantCommit := "7a74cee83f88e6585a5511c3cc53bdf0f5303d20" // the record's
+			if tc.heads != nil {
+				wantCommit = h2 // the source's head
+			}
+			if tc.wantRead && asked.sha != wantCommit {
+				t.Errorf("the forge was asked at %s, want %s", asked.sha, wantCommit)
+			}
 			wantReads := 1
 			if !tc.wantRead {
 				wantReads = 0
@@ -86,7 +93,7 @@ func TestARegisteredModuleIsIndexedFromItsRepository(t *testing.T) { // the gran
 			}
 			m, ok := moduleOf(t, mods, "snake")
 			if tc.want {
-				if !ok || m.Manifest == "" || m.Repository != "jschoubben/snake" || m.Commit != "7a74cee83f88e6585a5511c3cc53bdf0f5303d20" || m.Path != pathOf(dirOf(tc.path)) {
+				if !ok || m.Manifest == "" || m.Repository != "jschoubben/snake" || m.Commit != wantCommit || m.Path != pathOf(dirOf(tc.path)) {
 					t.Fatalf("modules.snake = %+v, found %v", m, ok)
 				}
 				if len(ix.Manifests.(*memStore).vals) != 1 {
-- 
2.54.0