Bun Rust rewrite: "codebase fails basic miri checks, allows for UB in safe rust"

Post by saidnooneever » Sat, May 16, 2026, 6:39 PM UTC

Animats wrote: post #70

smasher164 wrote: post #60

What I don't understand is if they were going to translate Zig to unsafe Rust, why not just build a translation tool for it? You could do a one-to-one mapping of language constructs, hardcoding patterns in your codebase, and as one friend put it "Tbh they could've just hooked up zig translate-c to c2rust". They would get deterministic translation, would probably have not been a heavy investment to build, and the outp…

> "Tbh they could've just hooked up zig translate-c to c2rust". Have you ever seen what comes out of c2rust? It's awful. It relies on a library of functions which emulate unsafe C pointer semantics with unsafe Rust. A few years ago, when I was struggling with bugs in OpenJPEG (a JPEG 2000 decoder), someone tried running it through c2rust. The converted unsafe rust segfaulted at the same place the C code did. It's com…

Post by [deleted] » Sat, May 16, 2026, 7:15 PM UTC

veidr wrote: post #315

gorjusborg wrote: post #229

Here's the thing: I was first interested in Bun because it was written in Zig. I was interested in Zig because I respected Andrew Kelley's decision-making, and his taste matched my own. I got really excited about Bun for many reasons after that, but they essentially came down to a similar root: the decisions were ones that I respected and would probably have made myself if I had thought of them. I was a little concer…

I can understand where you are coming from, but I myself am coming from a quite different place. I'm a long-time Deno fan, and to me Bun was less interesting because a.) it seemed like a much-less-ambitious Deno, and b.) I don't want to learn Zig, so I wasn't likely to try to hack on Bun itself, even just recreationally. But, I warmed up to Bun over the last couple years almost against my own will — trying to maintai…

Post by surajrmal » Sat, May 16, 2026, 7:50 PM UTC

chrisco255 wrote: post #220

minimaxir wrote: post #165

Earlier quoted context omitted.

I suspect "Rust is fast/low memory utilization" is the more common value proposition, with memory safety as the bonus that can push it over other fast languages. Related: If AI writes your code, why use Python? (which notes why Rust has taken off for LLMs) https://news.ycombinator.com/item?id=48100433

Zig is every bit as fast with typically even lower memory footprint as Rust. The main thing Rust promises that Zig cannot already do natively is memory safety. This is not about Python vs Rust. It is one systems language vs another.

Post by antonvs » Sat, May 16, 2026, 9:25 PM UTC

stickfigure wrote: post #211

antonvs wrote: post #156

Earlier quoted context omitted.

> Most of it strikes me as relatively shallow at the moment It is. We’re what, a week into this exercise? Absolutely everyone criticizing it, with no exceptions, is behaving like a micromanaging middle manager who couldn’t even dream of doing the work themselves. I half want to start a list of “people to ignore”, but such people tend to expose themselves in every other comment anyway.

It may just be different expectations about what the `main` branch means. In my organization we don't merge half-finished work into `main`.

Post by brokencode » Sat, May 16, 2026, 10:13 PM UTC

coldtea wrote: post #337

veidr wrote: post #335

Earlier quoted context omitted.

lol — what you're saying doesn't make sense to me, but I'm sure it makes sense to somebody What I was specifically referring to is Deno (originally) trying to fix the (glaring, fundamental) problems that Node imposes on the world, vs just do them faster.

Yes, but "fixing some fundamental Node problems" is a low bar, hardly the high mark of ambition now, was it? And to offer a counter example, something like Dart appeared much more ambitious to me.