diff --git a/package.json b/package.json
index 8c67ab7bd6..9255278d68 100644
--- a/package.json
+++ b/package.json
@@ -9,7 +9,7 @@
   "scripts": {
     "setup_js_dev": "git submodule init && git submodule update && cd home-assistant-js && npm install",
     "clean": "rm -rf build/* build-temp/*",
-    "js_dev": "npm run watch_ru_all",
+    "js_dev": "script/sw-dev.js && npm run watch_ru_all",
     "js_dev_demo": "BUILD_DEMO=1 npm run watch_ru_all",
     "js_prod": "BUILD_DEV=0 npm run ru_all",
     "js_demo": "BUILD_DEV=0 BUILD_DEMO=1 npm run ru_all",
diff --git a/script/sw-dev.js b/script/sw-dev.js
new file mode 100755
index 0000000000..0d7c304835
--- /dev/null
+++ b/script/sw-dev.js
@@ -0,0 +1,10 @@
+#! /usr/bin/env node
+
+var fs = require('fs');
+var path = require('path');
+
+var content = `
+console.warn('Service worker disabled in dev mode');
+`;
+
+fs.writeFileSync(path.join('build', 'service_worker.js'), content);
diff --git a/script/sw-precache.js b/script/sw-precache.js
old mode 100644
new mode 100755
index e88386bd73..e9dfe3bc75
--- a/script/sw-precache.js
+++ b/script/sw-precache.js
@@ -1,3 +1,5 @@
+#! /usr/bin/env node
+
 /*
 Generate a caching service worker for HA