Ask HN: What Technology/infrastructure is fueling the HN site?

I think its Arc: http://en.wikipedia.org/wiki/Arc_(programming_language)

"The site was created by Paul Graham in February 2007. Initially it was called Startup News or occasionally News.YC. On August 14, 2007 it became known by its current name.[2] It developed as a project of his company Y Combinator, functioning as a real-world application of the Arc programming language which Graham co-developed." -- http://en.wikipedia.org/wiki/Hacker_News

arc: http://en.wikipedia.org/wiki/Arc_(programming_language)

HN is implemented in PG.

And vice versa.

caching