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Neutron Drive(extinct, but source is available)Erbix(JavaScript-only is a bummer, possibly extinct)
Cloud-Only Models
- Codenvy
- Codenvy Beta - slightly better, no more runners, more like Cloud9
- Cloud9 Hosted
- Koding (they don't host - AWS / GCE only)
- CodeAnywhere (very bare-bones, although FTP support was cool)
- StackHive (not free / not open-source)
- CodeTasty (CSS / HTML / JavaScript-only)
- SourceLair (no test / runtime support, just editing and possibly compiling)
- Visual Studio Online (VERY thorough, but totally feels like a Windows application..t
- this one even offers project management / planning tools
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