diff --git a/package.json b/package.json
index eccdc41..0f20161 100644
--- a/package.json
+++ b/package.json
@@ -32,6 +32,6 @@
   },
   "devDependencies": {
     "chai": "^4.0.2",
-    "mocha": "^3.3.0"
+    "mocha": "^4.0.0"
   }
 }