diff --git a/runtime/runtime_controller.cc b/runtime/runtime_controller.cc
index b2a8f7a14389f..8c541c2ffecf0 100644
--- a/runtime/runtime_controller.cc
+++ b/runtime/runtime_controller.cc
@@ -398,6 +398,9 @@ bool RuntimeController::LaunchRootIsolate(
   }
 
   FML_DCHECK(Dart_CurrentIsolate() == nullptr);
+
+  client_.OnRootIsolateCreated();
+
   return true;
 }