Interesting. I thought it rang a bell, and I indeed ran across a version of this a few years ago, via this paper: <a href="http://queue.acm.org/detail.cfm?id=2330089" rel="nofollow">http://queue.acm.org/detail.cfm?id=2330089</a><p>However at the time it was Scheme-based. You wrote Scheme in one codebase, which was then compiled appropriately to (client- and server-side) JS plus HTML. At some point in the past 5 years it must've been overhauled to use JS as the unifying language instead of Scheme? I can't find a history page on the site or any information about that change, but I'd be curious to read about it.