diff --git a/package.json b/package.json
index 1ddf84a..55cd4ad 100644
--- a/package.json
+++ b/package.json
@@ -35,7 +35,7 @@
     "babel-core": "^6.3.26",
     "babel-loader": "^6.2.0",
     "babel-preset-es2015": "^6.3.13",
-    "chai": "^3.4.1",
+    "chai": "^4.3.3",
     "memory-fs": "^0.3.0",
     "mocha": "^2.3.4",
     "webpack": "^1.12.9"