diff --git a/angular.io/src/test.ts b/angular.io/src/test.ts
index 9bf72267e9..7eef72157c 100644
--- a/angular.io/src/test.ts
+++ b/angular.io/src/test.ts
@@ -1,5 +1,6 @@
 // This file is required by karma.conf.js and loads recursively all the .spec and framework files
 
+import 'zone.js/dist/zone';
 import 'zone.js/dist/long-stack-trace-zone';
 import 'zone.js/dist/proxy.js';
 import 'zone.js/dist/sync-test';