diff --git a/action.go b/action.go
index 13de62d..42301df 100644
--- a/action.go
+++ b/action.go
@@ -170,9 +170,10 @@ func (service *Service) RegisterActions(registrar ActionRegistrar) {
 //	service := dns.NewServiceWithRegistrar(dns.ServiceOptions{}, registrar)
 //	// registrar now exposes dns.resolve, dns.resolve.txt, dns.resolve.all, dns.reverse, dns.serve, dns.health, dns.discover
 func NewServiceWithRegistrar(options ServiceOptions, registrar ActionRegistrar) *Service {
-	service := NewService(options)
-	service.RegisterActions(registrar)
-	return service
+	if registrar != nil {
+		options.ActionRegistrar = registrar
+	}
+	return NewService(options)
 }
 
 // HandleAction executes a DNS action by name.
diff --git a/service.go b/service.go
index 19c5f77..ad32a83 100644
--- a/service.go
+++ b/service.go
@@ -109,6 +109,7 @@ type ServiceOptions struct {
 	ChainAliasDiscoverer         func(context.Context) ([]string, error)
 	FallbackChainAliasDiscoverer func(context.Context) ([]string, error)
 	TreeRootCheckInterval        time.Duration
+	ActionRegistrar              ActionRegistrar
 }
 
 // Options is the documented constructor shape for NewService.
@@ -156,7 +157,7 @@ func NewService(options ServiceOptions) *Service {
 		cached[normalizeName(name)] = record
 	}
 	treeRoot := computeTreeRoot(cached)
-	return &Service{
+	service := &Service{
 		records:                      cached,
 		reverseIndex:                 buildReverseIndexCache(cached),
 		treeRoot:                     treeRoot,
@@ -171,6 +172,12 @@ func NewService(options ServiceOptions) *Service {
 		fallbackChainAliasDiscoverer: options.FallbackChainAliasDiscoverer,
 		treeRootCheckInterval:        checkInterval,
 	}
+
+	if options.ActionRegistrar != nil {
+		service.RegisterActions(options.ActionRegistrar)
+	}
+
+	return service
 }
 
 func (service *Service) resolveHSDClient(client *HSDClient) (*HSDClient, error) {
diff --git a/service_test.go b/service_test.go
index 47aeed6..41607c8 100644
--- a/service_test.go
+++ b/service_test.go
@@ -1942,6 +1942,32 @@ func TestNewServiceWithRegistrarBuildsAndRegistersInOneStep(t *testing.T) {
 	}
 }
 
+func TestNewServiceAutoRegistersActionsWhenRegistrarIsConfigured(t *testing.T) {
+	registrar := &actionRecorder{}
+	service := NewService(ServiceOptions{
+		Records: map[string]NameRecords{
+			"gateway.charon.lthn": {
+				A: []string{"10.10.10.10"},
+			},
+		},
+		ActionRegistrar: registrar,
+	})
+
+	if service == nil {
+		t.Fatal("expected service to be built")
+	}
+
+	expected := service.ActionNames()
+	if len(registrar.names) != len(expected) {
+		t.Fatalf("expected constructor to auto-register %d actions, got %d: %#v", len(expected), len(registrar.names), registrar.names)
+	}
+	for index, name := range expected {
+		if registrar.names[index] != name {
+			t.Fatalf("unexpected auto-registered action at %d: got %q want %q", index, registrar.names[index], name)
+		}
+	}
+}
+
 func TestServiceActionDefinitionsHaveInvokers(t *testing.T) {
 	service := NewService(ServiceOptions{
 		Records: map[string]NameRecords{