I think that is the one actually because the looking at the post history [1] of the person you are responding to I find that the most recent post they made in the past was one titled “Linux on the Web” [2], which leads to that very URL that you found.
He also posted a comment in the thread with some more details:
> It makes heavy use of the HTML5 Filesytem for local storage, as well as Native Client for vim, python, and plugin codecs to enable highly configurable realtime a/v streaming via WebRTC peer connections. Windowed HTML5/JS applications can be developed live within the site itself. There is a feature to stream terminal sessions to each other, in order to show how to efficiently use vim to develop applications, for example.
He also posted a comment in the thread with some more details:
> It makes heavy use of the HTML5 Filesytem for local storage, as well as Native Client for vim, python, and plugin codecs to enable highly configurable realtime a/v streaming via WebRTC peer connections. Windowed HTML5/JS applications can be developed live within the site itself. There is a feature to stream terminal sessions to each other, in order to show how to efficiently use vim to develop applications, for example.
[1]: https://news.ycombinator.com/submitted?id=denniskane
[2]: https://news.ycombinator.com/item?id=10977459