Why does rake assets:precompile in development cause problems but not in my production environement

I have upgraded my app on heroku to a cedar stack so that the asset pipeline works. I have followed the instructions given in heroku's docs by choosing to compile assets locally. This has created a directory public/assets. Everything in production works perfectly(css, js, with no problems). Going back to my development environment seems to cause the js to not function properly. In environments/pro

[seapig_dolphin]

わからん。。。