diff --git a/ember/ember-tests.ts b/ember/ember-tests.ts
index d51c1635bf..dda0e157c4 100644
--- a/ember/ember-tests.ts
+++ b/ember/ember-tests.ts
@@ -160,7 +160,15 @@ promise.then(function(value: any) {
   // on rejection
 });
 
-var component1 = Ember.Component.extend({
+var mix1 = Ember.Mixin.create({
+  foo: 1
+});
+
+var mix2 = Ember.Mixin.create({
+  bar: 2
+});
+
+var component1 = Ember.Component.extend( mix1, mix2, {
   lyft: Ember.inject.service(),
   cars: Ember.computed.readOnly('lyft.cars')
 });
diff --git a/ember/index.d.ts b/ember/index.d.ts
index 4322524901..708adc160c 100644
--- a/ember/index.d.ts
+++ b/ember/index.d.ts
@@ -874,7 +874,8 @@ declare namespace Ember {
         @param {Object} [args] - Object containing values to use within the new class
         **/
         static extend<T>(args?: CoreObjectArguments): T;
-        static extend<T>(mixins?: Mixin, args?: CoreObjectArguments): T;
+        static extend<T>(mixin1: Mixin, args?: CoreObjectArguments): T;
+        static extend<T>(mixin1: Mixin, mixin2: Mixin, args?: CoreObjectArguments): T;
 
         /**
         Creates a new subclass.