Don't trigger installation when in development mode

download/install.js

@@ -5,6 +5,13 @@ var path = require('path')
 var fs = require('fs')
 
 var dist = path.join(__dirname, 'dist')
+var src = path.join(__dirname, 'src')
+
+// Don't install when developing locally
+if (fs.existsSync(src)) {
+  process.exit(0)
+}
+
 var download = path.join(dist, 'download.js')
 
 try {