I have no idea whether the new or old code is/was good, just pointing out what seems like a plausible thought process for people who object to this rewrite.
I mean, until very recently, the idea that one million lines of code could be written (rather than mechanically translated) in a month was unbelievable.
It is clearly the case that times have changed since the tools have been updated. So if we challenge one assumption, why not also challenge the other?
Bun presumably will have access to Mythos, which is purportedly reviewing million line code-bases (Mozilla, etc.) and uncovering real value for the devs of those projects.
I find it hard to deny extrapolating these trends to this Bun rewrite.
It is still unbelievable, because it still has not happened in this case. The agent wrote it. Nobody thinks it's unbelievable that an LLM can generate a million lines of code in a month. You either do not understand what the detractors are saying or are arguing in bad faith
But AFAICT he's never suggested they reviewed all the code, and that they didn't seems like a pretty safe assumption given the volume, and timeline.
I personally think the test suite passing counts for something, and I would bet they also set up some pretty intense LLM-powered verification loops and quality gates (which I hope the forthcoming blog post will detail). I've seen mechanical LLM ports that went extremely well (though nowhere near this scale, so we could review the code (which is how I know they went well)).
I think the most hysterical reactions that we are seeing from some people are premature, knee-jerk responses. We're gonna _find out_ if the Rust version really is better than Zig version, and soon.
And even if it is better overall, I think if there is an AI-slop-induced major bug we are definitely gonna know that, too, because we have a highly motivated community of folks ready to tweet the shit out of it the instant it is found.
So even as a pretty heavy daily user of Bun, I'm actually really glad they did this. The value of the public experiment is high, and if new Bun sucks, well, I still have Deno.