diff --git a/package.json b/package.json
index 2ac5c7e..2e31f04 100644
--- a/package.json
+++ b/package.json
@@ -34,7 +34,7 @@
     "babel-preset-nodejs-lts": "1.2.1",
     "babel-register": "6.6.5",
     "coveralls": "2.11.9",
-    "es6-promisify": "3.0.0",
+    "es6-promisify": "4.0.0",
     "eslint": "2.6.0",
     "fs-extra": "0.26.7",
     "nyc": "6.1.1",