How is the Bun Rewrite in Rust going?

Node has 4-6 weeks without a meaningful release (other than security stuff) pretty much every December. I think the criticism in the article is unfounded and whomever needed/wanted a release should have asked first instead of writing an "angry" blog post.

(I'm a Node.js maintainer)

- How many people have updated Claude/Bun to the latest version.

- How many subscribers care about reporting issues. Most of them are forced to use the tool against their will and have mentally checked out already. Why report issues if your employer values slop code anyway. Just log the hours and keep your head down. Maybe it is not expedient for the AI narrative to report issues!

- How many subscriptions are real vs. bulk distiller accounts.

- If subscriber numbers are inflated.

Judging by the weird Claude Code Github issues page, there are suspiciously few new issues: about 2 to 3 a day only vs. alleged subscriber numbers of 4 million.

I look forward to the postmortem!

I think they're taking things "gradually" as they are under a lot of scrutiny and no rush for full release.

If you explore Github, you're gonna see thousands of abandoned game engines, compilers for made-up languages. And that has been happening since before the LLM era.

I used to be part of an OS messaging board in the early 2000s and almost everyone had their own OS. A dozen people or so could even run Firefox! I remember (now legend) Terry bothering us to check out LoseThos or GodOS or whatever was its name, but quite a few people had OSs that could do more than that.

Not all software needs to be commercial to be useful, even if it's just for a learning experience. I have learned a lot from those experiments, even if they're not polished.

But it seems like we're finally starting to accept that "accidentals" like network effects, ownership, accountability, etc. are important. Of course, that's why many of us fled to technical corners in the first place - because the "accidentals" become tied up with things like nepotism, unfair and arbitrary judges from random humans who don't understand your merit, the need for bullshitting more than real technical value. Supposedly, anyways.

I worked for a startup that stopped feature development and did a complete rewrite of a huge codebase. I was assigned to a side project during this time and missed the entire rewrite process. I came back to a completely rewritten codebase.

There was almost no learning curve, despite being in an entirely different language. The core architecture, data structures, and concepts were the same.

If you read the Bun blog post on how they did it, their rewrite was similar: The first step was getting it into a new language, not rearchitecting it from scratch.

I think they did it the right way based on my pre-LLM. Rewriting into a different language as fast and basically as possible is important for getting the team switched over quickly. Rewriting into a different language in X days is actually a good goal to minimize.

Short-termism at its peak. Code maintainers will learn the hard way how to set the boundaries between ai-generated code, and human maintainable code.

Also if you whip something up, you tend not to care for it as much as something you took the time to create in a "proper" manner.

What do you think of https://scramblequest.app and https://wordpeek.app ?

I have never looked at any of the code for them

edit: Yeesh, misread your comment as "word games" not "word clones" and was very confused about the claim. Probably should have noted my confusion and re-read.

Not really. Transpilers have existed since forever.

The hard part is all the edge cases. (And LLMs don't solve this problem; they probably akshually exacerbate it.)

The main issue that justified the rewrite were memory bugs, especially related to interaction with GC managed Javascript objects. There is no fully general way to prevent those bugs in Zig, and I don't see any claims that they did so in Buz.

I consider typing to be secondary to software engineering, but I do concede that for those cases that typing really is the bottleneck, LLMs can certainly be of value.

Those cases are rare, though.

No one on their team had Rust experience

There are so many non-quantifiable properties to evaluate of the 'before' and 'after' codebases. Choices and preferences to be had about languages, language porting in general, and LLM coding.

After all that, pretend we could have a clear convincing distillation of the port and want to go apply the lessons learned. If someone doesn't get LLM porting results as good as Bun did, or it cost them substantially more in tokens, then they're "holding it wrong." If someone is underwhelmed by Bun's results, then it was just a proof of concept and the models have gotten so much better in the last 6 months anyway you can't compare.

I imagine the $800k or whatever this has cost is coming out of Anthropic's marketing budget, so they can make a big splash about it.

To the contrary, I think any problem with this release would be jumped on harshly so they're being more careful than usual. There's not a rush for the community to move to 1.4 and any issues could poison the community trust.

Bun is a major part of the web ecosystem, having it developed by them via AI, sounds like a gigantic pr win.

If it was about Claude Code itself, they could have rewritten it. They keep saying they don't even write code any more, so it shouldn't even matter what language it's in.

and ho, the bloat, do not forget the bloat, which is technical debt towards the future.

I am not anti-ai per-se, but I consider the software I write as a prouct to add features to and maintain over time. So in this case I think it is not wise to say that bc you got something impressive fast you are done. Now you have bugs, architecture, bloat removal, and others...

Letting an AI manage all the workflow is a recipe for disaster in anything that is not strictly short-term. For this reason, I hardly code one-off scripts myself anymore and I hardly use AI for big things besides discussions with the prompt, reviews and snippets. For adding tests it can also be useful.

For full, long-term products, they try to sell agents, and tokens and the like. I think they do not work well enough what I tried. It always ends up as a bloated unmantainable mess.

Unless something that is totally autonomous (by this I mean 100% autonomous) and automated ever exists, I see writing software that can be maintained by humans still critical. As long as this exists, the productivity upper bound will be that of humans reviewing and driving the workflow, even if with AI support.

I use more (albeit cached) when centering a div.

I keep seeing this. What is "un-idiomatic" rust?

That's very easy to prevent. Don't let them edit the tests! Run the test suite against a reserved copy.

Oh, that company that I heard did not use humans aymore to write software and bragged about it? I heard, correct me if I am wrong.

Something does not match here...

The author's assumption is that a rewrite is not just a mechanical translation of code - it's also a state of stability. And no release, for the author (I agree) means no stability.

It's like a developer who says that after a week of work, a feature is 90% ready, but the other 10% is still not ready (for release) after months.

Hence, the author concludes that rust rewrite is not complete as bun in rust is not released yet.

I agree with author's POV.

This is one of the funnier takes on the rewrite. Bun was held up as a flagship Zig project for years. Then they chose to rewrite in Rust and everyone up to the Zig author has suddenly switched to claiming that Bun was terrible code all along.

Perhaps. But were that the case, one would think they'd be quite eager to say so.

One single product, AFAIK, and one ladden with bugs and issue too.

Thankfully now I have some good material to post-rationalise my intuitive dislike

We can't have commited and involved people working on opensource stuff and simultaneously avoid drama when their sence of identity/beliefs/pride is devalued.

You and me both friend!