diff --git a/build_apprtc_appengine_app.py b/build_apprtc_appengine_app.py
index c1f91b2..40c0eb2 100755
--- a/build_apprtc_appengine_app.py
+++ b/build_apprtc_appengine_app.py
@@ -55,6 +55,10 @@
     return ('Missing grunt-cli in the apprtc checkout; did '
             'npm install fail?')
 
+  if utils.GetPlatform() is 'win':
+    # https://github.com/webrtc/apprtc/issues/48
+    print 'grunt build is broken on win; cannot build apprtc'
+    return
   utils.RunSubprocessWithRetry([node_bin, local_grunt_bin, 'build'])