alt Hacker NewsBun's Rust rewrite has been merged
Comments
> +1009257 -4024
Bun is now over 1M lines of Rust code.
This is approaching the size of the Rust compiler itself; except that BunJs is mostly a JavaScript interpreter wrapper + a reimplementation of the NodeJS library (Rust STD wrapper).
I think BunJS is becoming the canary for software complexity management in the LLM era.
About 9 days ago, Jarred wrote that it was far from certain that this would merge and that it was an overreaction. Ironic.
As an educational thread, see this one from a week ago where Jarred again deflects from a merge decision and legions of foot soldiers attack anyone who predicted the impending merge:
https://news.ycombinator.com/item?id=48073680
Didn't age well, did it?
I'm confused. Never heard of Bun until a few days ago here on HN. It's some nodejs wrapper thingy, written in Zig, and someone decided to use LLM to rewrite it in Rust. Is this a big deal? Who is even using this software? Why is this big?
$ rg 'unsafe [{]' src/ | wc -l
10428
$ rg 'unsafe [{]' src/ -l | wc -l
736
Language Files Lines Code Comments Blanks
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Rust 1443 929213 732281 116293 80639
Zig 1298 711112 574563 59118 77431
TypeScript 2604 654684 510464 82254 61966
JavaScript 4370 364928 293211 36108 35609
C 111 305123 205875 79077 20171
C++ 586 262475 217111 19004 26360
C Header 779 100979 57715 29459 13805first major company to really nuke their main product via AI psychosis?
Well, that escalated quickly. I think I first heard rumors of this a week or two ago. That's a very vast turnaround for such massive code-churn. I don't know how to feel about this.
Github is failing to load the 800 comments, naturally. I'll bet they're fun.
I have full faith, it's the same really smart people that built bun (Jarred and team) that have spearheaded this and are running it. So I have no reason to believe that this was done carelessly.
That said, I'm still shocked and amazed that something this big is possible these days. But as we've seen multiple times now, one of the most important things your codebase can have is a solid test suite.
I will continue to use bun, because at the end of the day, it isn't just the technology, but the talent/people behind the technology that ensures that it will be solid.
And since that hasn't changed, I will still trust bun and its direction.
Also, bun is mostly glue code and sort of "user space" libraries (my words) as Jarred has said on X, most of the underlying runtimes like JavascriptCore, etc weren't rewritten.
So this isn't like 100% of what we think of as bun was rewritten. It's more like the scaffolding and harness.
What does this mean for bun add-ons like opencode's opentui? Did FFI also somehow get ported or will that have to be updated? https://github.com/anomalyco/opentui
It's going to be absolute mess of total AI slop and black box that nobody understands and is going to cause more issues than it fixes.
Wow. This is going to be interesting to follow. There's absolutely no way any of this code was reviewed, but maybe we're in a post-human world now where you can trust the models to write and review the code. This is like Gastown but on a higher profile project. Will be fascinating to see how this project is able to add new features going forward (or even _if_ it will be able to).
Does anyone know how exactly Bun is used by Anthropic? Is it a part of Claude Code? I'm more than slightly worried about using Bun going forward myself, but I'm not sure to what extent that applies to using Claude as well.