I've made the source code for Two Stop Bits available at https://github.com/jgrahamc/twostopbits I have not made any changes to the Arc language itself, and so all the interesting stuff is in https://github.com/jgrahamc/twostopbits/tree/master/apps/news Most of the changes are to news.arc but also in the static/ directory where I've modified the CSS and added static images.
This is the current version that I'm hacking on (not quite what's running) and has experimental support for tags (which isn't 100% perfect yet).
I would love if folks worked on the CSS and getting mobile support to look right.
https://news.ycombinator.com/item?id=37927480