well that is very cool. Unfortunately the original HN posts title failed to mention that was meant for embedded control systems which is probablly why I missed reading it! The HN post can be found here :-
It wasn't originally written in literate style, but it was a very large codebase which almost nobody understood. Tim Daly put an enormous amount of effort into making it literate, so that anybody can be introduced to it.
Something like this
https://github.com/nakkaya/ferret
The whole source code is in literate form in one org file.