diff --git a/map.json b/map.json
index 96c88caab8..704f1326aa 100644
--- a/map.json
+++ b/map.json
@@ -6,6 +6,7 @@
   "console": "console-browserify",
   "constants": "constants-browserify",
   "crypto": "crypto-browserify",
+  "core-util-is": null,
   "dgram": null,
   "dns": null,
   "domain": "domain-browser",
diff --git a/package.json b/package.json
index 3fb2f783fc..76661f25f6 100644
--- a/package.json
+++ b/package.json
@@ -6,7 +6,8 @@
   "main": "index.js",
   "license": "MIT",
   "scripts": {
-    "prepublish": "node scripts/build-deps.js"
+    "prepublish": "node scripts/build-deps.js",
+    "postinstall": "node scripts/rm-core-utils.js"
   },
   "dependencies": {
     "assert": "^1.4.1",
diff --git a/scripts/rm-core-utils.js b/scripts/rm-core-utils.js
new file mode 100644
index 0000000000..3f5cce5b6a
--- /dev/null
+++ b/scripts/rm-core-utils.js
@@ -0,0 +1,3 @@
+require("rimraf").sync(require("path").join(
+  __dirname, "..", "node_modules", "**", "core-util-is"
+));