Hacker News was written in the Arc lisp dialect, a dialect created by Paul Graham. Arc was implemented on top of Racket, but that has now changed. HN runs on top of SBCL since a few months. But why? For performance reasons. I recently noticed that Hacker News no longer uses paging for long threads. In the past, when a discussion grew large, we had to click “More” to load the next page of comments, and dang would occasionally post helpful tips to remind us about this feature. Was there an announc...