My initial reaction was that this is pure insanity but in fairness this is a fairly 1:1 port of existing code, so the developer's mental model of it should still match fairly well.
For instance look at this Zig function: https://github.com/oven-sh/bun/blob/ed1a70f81708d7d137de8de0...
Versus this Rust version: https://github.com/oven-sh/bun/blob/ed1a70f81708d7d137de8de0...
I did pick that at random but it does look like the best case. I skimmed through a lot of the Rust code and there's a surprisingly small amount of `unsafe`.
Still pretty insane to merge this in such a short time with so little testing, but I can easily think of bigger software engineering mistakes. Hell it's not like Bun even needs to be commercially successful any more.
It’s still 400k more lines