[Kaizyn]

The source code used to be open, and it isn't clear what happened to it. Maybe ask over on the arclanguage.org forum as HN is written in arc.

The closest thing to a source repo is this from many years ago: https://github.com/wting/hackernews

[akkartik]

The official sources are at http://arclanguage.org/install

Community-supported version: http://arclanguage.github.io

[j_s]

https://news.ycombinator.com/item?id=11176894

> A version of HN's source code is included with the public release of Arc, but HN's algorithm has many extensions that aren't public.

https://news.ycombinator.com/item?id=13456306

> We're unlikely to publish all that because doing so would increase two bad things: attempts to game the site, and meta nitpicking.

Including at least at one time a Chrome extension for moderation:

https://news.ycombinator.com/item?id=11670071#11670562

[krapp]

Hacker News deviates from the original Arc code, though. Unfortunately, because YCombinator wants to protect their secret sauce, they're not likely to release anything interesting.

One can hope, though.

[frik]

The current code base would be interesting.

The HN frontpage algorithms used to be more predictable, now it's a black box.