diff --git a/lib/index.js b/lib/index.js
index 388fecd4c0..5287e4ead0 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -370,6 +370,7 @@ Server.prototype.serve = function(req, res){
   }
 
   debug('serve client source');
+  res.setHeader("Cache-Control", "public, max-age=0");
   res.setHeader('Content-Type', 'application/javascript');
   res.setHeader('ETag', expectedEtag);
   res.writeHead(200);