[krapp]

Dang once mentioned that the actual HN codebase is full of YC business code that would be very difficult to extricate - and that parts of it like the spam filters and flamewar detector they want to keep secret to prevent people from gaming the system. Also that he just doesn't have time to do it.

As far as "secret sauce" goes, the sauce is that the mods actively upweigh, downweigh and filter user accounts all the time. Trying to reverse engineer a working algorithm from this site's behavior is a fool's errand.