Check this out: https://github.com/hmarr/codecube 1. It's open source 2. Put this on heroku and use it privately. 3. Highly stable(because it's write using golang, you can run millions of request, and it's still work fine) ??? NONPROFIT

But project no longer in developing, so i guess maybe someone wants to reanimate codecube? On weekends for example, contact me: iamjacke AT gmail.com