I've taken the approach of writing and even directly reviewing almost no code for this, otherwise I'd simply not have time for it as another side project. It's also interesting to see how far I can push this "vibe engineering" approach, and although it's not perfect, the answer is much further than I'd have expected going in.

I've managed to get OpenCode setup such that I can have a productive discussion about the design or an issue / change then leave the LLM iterating for long periods while I do other work. It's instructed to maintain test coverage and treat quality very seriously - as a result there are over 5000 tests (some I suspect are useless...) and it's pretty rare to get a regression.

I'm pretty sure there are plenty of significant bugs and gaps, but also that once found it seems like all of them will be fixed pretty quickly by the LLM.

I just have to avoid looking at the code...