Comment by aroman

holy cow this thing has like 70 repositories!

And I found a screenshot... looks very much like sublime text: https://f.cloud.github.com/assets/1424/1228569/cce6eb26-27a6...

edit: based on this[1], it looks like this is a GitHub-aware/integrated text editor that targets both desktop (Mac, at least) and web

[1] https://gist.github.com/elcuervo/eb68883f233baf5a46c8