diff --git a/doc/thinking/2026-04-26-namespace-manager-step37.md b/doc/thinking/2026-04-26-namespace-manager-step37.md
new file mode 100644
index 00000000..482cf0e8
--- /dev/null
+++ b/doc/thinking/2026-04-26-namespace-manager-step37.md
@@ -0,0 +1,19 @@
+# 2026-04-26 — NamespaceManager rewrite, step 37
+
+## Цель шага
+
+Убрать дублирование startup manager flow в трёх namespace watcher-ах.
+
+## Что меняем
+
+1. В `utils` добавляем helper `NewWatcherNamespaceManager()`.
+2. Helper:
+   - создаёт `NamespaceManager`
+   - подписывает subscriber-ов
+   - выполняет `BootstrapAndDispatch()`
+3. `buildermgr`, `router`, `executor/multitenant` используют новый helper.
+
+## Что НЕ меняем
+
+- не меняем semantics dispatch;
+- не меняем runtime cleanup policy.
\ No newline at end of file
diff --git a/pkg/buildermgr/ns_watcher.go b/pkg/buildermgr/ns_watcher.go
index d0f22cfd..a55ab8f2 100644
--- a/pkg/buildermgr/ns_watcher.go
+++ b/pkg/buildermgr/ns_watcher.go
@@ -30,9 +30,8 @@ func StartNSWatcher(
 	pkgw *packageWatcher,
 	mgr manager.Interface,
 ) {
-	nsManager := utils.NewNamespaceManager()
-	nsManager.Subscribe(NewNamespaceSubscriber(envw, pkgw, mgr))
-	if _, err := nsManager.BootstrapAndDispatch(ctx, utils.DefaultNSResolver().Snapshot(), utils.NamespaceSourceEnv, time.Now().UTC()); err != nil {
+	nsManager, err := utils.NewWatcherNamespaceManager(ctx, utils.DefaultNSResolver().Snapshot(), utils.NamespaceSourceEnv, time.Now().UTC(), NewNamespaceSubscriber(envw, pkgw, mgr))
+	if err != nil {
 		logger.Error("buildermgr.NSWatcher: BootstrapAndDispatch failed", zap.Error(err))
 	}
 
diff --git a/pkg/executor/multitenant/ns_watcher.go b/pkg/executor/multitenant/ns_watcher.go
index 2a0b4f90..2eccfe1f 100644
--- a/pkg/executor/multitenant/ns_watcher.go
+++ b/pkg/executor/multitenant/ns_watcher.go
@@ -92,9 +92,8 @@ func StartNSWatcher(
 	executorTypes map[fv1.ExecutorType]executortype.ExecutorType,
 	mgr manager.Interface,
 ) {
-	nsManager := utils.NewNamespaceManager()
-	nsManager.Subscribe(NewNamespaceSubscriber(logger, kubernetesClient, executorTypes, mgr))
-	if _, err := nsManager.BootstrapAndDispatch(ctx, utils.DefaultNSResolver().Snapshot(), utils.NamespaceSourceEnv, time.Now().UTC()); err != nil {
+	nsManager, err := utils.NewWatcherNamespaceManager(ctx, utils.DefaultNSResolver().Snapshot(), utils.NamespaceSourceEnv, time.Now().UTC(), NewNamespaceSubscriber(logger, kubernetesClient, executorTypes, mgr))
+	if err != nil {
 		logger.Error("multitenant.NSWatcher: BootstrapAndDispatch failed", zap.Error(err))
 	}
 
diff --git a/pkg/router/ns_watcher.go b/pkg/router/ns_watcher.go
index 94506b15..787357a3 100644
--- a/pkg/router/ns_watcher.go
+++ b/pkg/router/ns_watcher.go
@@ -30,9 +30,8 @@ func StartNSWatcher(
 	ts *HTTPTriggerSet,
 	mgr manager.Interface,
 ) {
-	nsManager := utils.NewNamespaceManager()
-	nsManager.Subscribe(NewNamespaceSubscriber(ts, mgr))
-	if _, err := nsManager.BootstrapAndDispatch(ctx, utils.DefaultNSResolver().Snapshot(), utils.NamespaceSourceEnv, time.Now().UTC()); err != nil {
+	nsManager, err := utils.NewWatcherNamespaceManager(ctx, utils.DefaultNSResolver().Snapshot(), utils.NamespaceSourceEnv, time.Now().UTC(), NewNamespaceSubscriber(ts, mgr))
+	if err != nil {
 		logger.Error("router.NSWatcher: BootstrapAndDispatch failed", zap.Error(err))
 	}
 
diff --git a/pkg/utils/namespace_manager.go b/pkg/utils/namespace_manager.go
index cd960865..4fa70ebb 100644
--- a/pkg/utils/namespace_manager.go
+++ b/pkg/utils/namespace_manager.go
@@ -88,6 +88,18 @@ func NewBootstrappedNamespaceManager(resolver *NamespaceResolver, source Namespa
 	return manager
 }
 
+func NewWatcherNamespaceManager(ctx context.Context, namespaces []string, source NamespaceSource, observedAt time.Time, subscribers ...NamespaceSubscriber) (NamespaceManager, error) {
+	manager := NewNamespaceManager()
+	for _, subscriber := range subscribers {
+		if subscriber == nil {
+			continue
+		}
+		manager.Subscribe(subscriber)
+	}
+	_, err := manager.BootstrapAndDispatch(ctx, namespaces, source, observedAt)
+	return manager, err
+}
+
 func (m *inMemoryNamespaceManager) Subscribe(subscriber NamespaceSubscriber) {
 	m.mu.Lock()
 	defer m.mu.Unlock()
diff --git a/pkg/utils/namespace_manager_test.go b/pkg/utils/namespace_manager_test.go
index 0727cc19..975ffec5 100644
--- a/pkg/utils/namespace_manager_test.go
+++ b/pkg/utils/namespace_manager_test.go
@@ -270,6 +270,21 @@ func TestNewBootstrappedNamespaceManager(t *testing.T) {
 	}
 }
 
+func TestNewWatcherNamespaceManager(t *testing.T) {
+	router := &testNamespaceSubscriber{name: "router"}
+	builder := &testNamespaceSubscriber{name: "buildermgr"}
+	manager, err := NewWatcherNamespaceManager(context.Background(), []string{"tenant-b", "tenant-a"}, NamespaceSourceEnv, time.Now().UTC(), router, builder)
+	if err != nil {
+		t.Fatalf("expected watcher manager bootstrap success: %v", err)
+	}
+	if !reflect.DeepEqual([]string{"tenant-a", "tenant-b"}, manager.Snapshot()) {
+		t.Fatalf("expected watcher manager snapshot to match bootstrapped namespaces")
+	}
+	if router.addCalls != 2 || builder.addCalls != 2 {
+		t.Fatalf("expected all subscribers to receive bootstrap dispatch calls")
+	}
+}
+
 func TestNamespaceManagerDispatchAdd(t *testing.T) {
 	manager := NewNamespaceManager()
 	manager.Upsert(NamespaceEvent{Type: NamespaceEventAdd, Name: "tenant-a", Source: NamespaceSourceWatcher})