diff --git a/build/package.json b/build/package.json
index bc725017e9..4ca1c672bd 100644
--- a/build/package.json
+++ b/build/package.json
@@ -23,7 +23,8 @@
     "karma-junit-reporter": "*",
     "karma-phantomjs-launcher": "*",
     "phantomjs-prebuilt": "*",
-    "node-sass": "~4.1.1"
+    "node-sass": "~4.1.1",
+    "sinon": "*"
   },
   "engine": "node >= 6.9"
 }