diff --git a/package.json b/package.json
index 2d0fcb5..853684e 100644
--- a/package.json
+++ b/package.json
@@ -41,7 +41,7 @@
     "rimraf": "^2.5.0"
   },
   "dependencies": {
-    "async": "^1.4.2",
+    "async": "^2.2.0",
     "eventsource": "^0.1.6",
     "lodash.last": "^3.0.0",
     "lodash.mapvalues": "^4.6.0",