diff --git a/package.json b/package.json
index 2aba86a..1709f2b 100644
--- a/package.json
+++ b/package.json
@@ -32,6 +32,7 @@
     "routes": "^1.2.0",
     "lodash": "~3.0.0",
     "vis": "~3.9.1",
-    "extend": "~2.0.0"
+    "extend": "~2.0.0",
+    "bluebird": "~2.3.2"
   }
 }