diff --git a/package.json b/package.json
index 74c933b..edf927e 100644
--- a/package.json
+++ b/package.json
@@ -46,7 +46,6 @@
     "compression": "^1.7.1",
     "eslint": "^4.13.1",
     "eslint-plugin-import": "^2.8.0",
-    "esm": "^3.0.28",
     "express": "^4.16.3",
     "get-port": "^3.2.0",
     "mocha": "^5.0.4",