diff --git a/lib/redux/group/group_state.dart b/lib/redux/group/group_state.dart
index ee070375b..673075308 100644
--- a/lib/redux/group/group_state.dart
+++ b/lib/redux/group/group_state.dart
@@ -1,3 +1,4 @@
+import 'dart:async';
 import 'package:built_value/built_value.dart';
 import 'package:built_value/serializer.dart';
 import 'package:built_collection/built_collection.dart';
diff --git a/stubs/redux/stub/stub_state b/stubs/redux/stub/stub_state
index 6c9acadfc..ea3f2c845 100644
--- a/stubs/redux/stub/stub_state
+++ b/stubs/redux/stub/stub_state
@@ -1,3 +1,4 @@
+import 'dart:async';
 import 'package:built_value/built_value.dart';
 import 'package:built_value/serializer.dart';
 import 'package:built_collection/built_collection.dart';