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Bun's experimental Rust rewrite hits 99.8% test compatibility on Linux x64 glibc

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Re: Bun's experimental Rust rewrite hits 99.8% test compatibility on Linux x64 glibc

#291
post #212
post #74

Earlier quoted context omitted.

"No one has the intention of building a wall" - Walter Ulbricht, chairman of the central committee, a couple of months before the Berlin Wall was built. The AI companies and their associates are beginning to surpass that level of denials and lies.

you know this whole exercise is both a marketing exercise and a way to make noise. would the world come to a standstill tomorrow if every Bun instance out there ran on Node.js ? they know their A.I can't sell without the noise that it's now on the edge of the frontier. this is hype. zig adopting a strict 'no LLM' policy affects the LLM vendors.

Exactly. Always asks “who benefits from this?” . The answer in this case is: AI vendors, not us.

Re: Bun's experimental Rust rewrite hits 99.8% test compatibility on Linux x64 glibc

#292
post #212

Earlier quoted context omitted.

you know this whole exercise is both a marketing exercise and a way to make noise. would the world come to a standstill tomorrow if every Bun instance out there ran on Node.js ? they know their A.I can't sell without the noise that it's now on the edge of the frontier. this is hype. zig adopting a strict 'no LLM' policy affects the LLM vendors.

If you think Claude needs manufactured hype at this point to sell it you're delusional.

If you think they can survive without hype, you are the naive one

Re: Bun's experimental Rust rewrite hits 99.8% test compatibility on Linux x64 glibc

#293

Earlier quoted context omitted.

> Now it needs to be put into shape so that all the unsafe blocks are eliminated All the unsafe seems to be FFI? https://github.com/search?q=repo%3Aoven-sh%2Fbun+unsafe+lang... > and the code is turned into maintainable, readable, reasonably idiomatic Rust. I wonder how long is it going to take. This isn't a c2rust rewrite?

That GitHub search only covers the main branch, not the not-yet-merged Rust rewrite; the only Rust code in there is tests for Rust FFI (so that people can write native extension modules for Bun in Rust if they want to). The rewrite's in https://github.com/oven-sh/bun/tree/claude/phase-a-port . By running the following command on it, I count about 14,000 unsafe blocks: rg --stats -g '*.rs' 'unsafe \{|unsafe impl|#!?\[…

I have not had time to look at the code myself, but from when this was initially posted to Reddit, IIRC it had around a thousand global mutable variables, which are unsafe to access.

I am very curious what the numbers are once the test suite passes and after a few passes of reducing the amount of unsafe.

Re: Bun's experimental Rust rewrite hits 99.8% test compatibility on Linux x64 glibc

#294

6 days of work to do this. Even if it doesn't end up becoming meaningful, it shows just how tokens and work done will be linked now and in the future. It's going to be hard to compete with someone or a company that has more compute. They will just be able to do things you can't.

Translating a project that includes a good test suite from one language to another is known to be a great case where LLMs work well. When you’re starting with a complete codebase to use as an example and a test suite to check everything it’s much easier to iterate toward the desired goal. The LLM can already see what the goals are and how they’ve been implemented once already, which is a much easier problem than star…

It's not hard to imagine a future where the only things committed to git repos are tests and specs.

Re: Bun's experimental Rust rewrite hits 99.8% test compatibility on Linux x64 glibc

#295

6 days of work to do this. Even if it doesn't end up becoming meaningful, it shows just how tokens and work done will be linked now and in the future. It's going to be hard to compete with someone or a company that has more compute. They will just be able to do things you can't.

Unclear. Very good products tend to be about doing one or a few things very well; not about doing tons of stuff. So far, all I see is “Man, Im a 10x engineer now!”, shipping more code but without clear direction and taste. At this point, most of LLM-based work is just noise.

Re: Bun's experimental Rust rewrite hits 99.8% test compatibility on Linux x64 glibc

#296

Serious question… Who’s going to want to run a vibe coded runtime in production? I don’t see how this is a good look for Bun?

One should care about tests more than how code was coded.

If I had a codebase with lots of tests and asked someone else to rewrite it to another language passing the same test suite, I honestly wouldn't expect a great quality job.

I say this because it happened 3 times in the company I work for: we conducted experiments by tasking different companies to rewrite the same code in another language. All of them passed (most) of the tests, but code quality was low. If the job is a black box, rely on the I/O to determine quality, not the inner workings.

Re: Bun's experimental Rust rewrite hits 99.8% test compatibility on Linux x64 glibc

#297

Earlier quoted context omitted.

Software companies have been about automating human labor since the invention of computers. It's the whole damn point. Why do you think finance used to be (sometimes still is) the head of the IT dept? Because we automated accounting away. Then typists. Then secretaries. Then drafting. Etc etc.

There are software components out there that are the backbone of our industry, and they are not governed by multibillion dollar companies. Linux, postgres, HTTP, TCP/IP, qemu,… It’s not that anthropic/google/openai/etc are unavoidable

> they are not governed by multibillion dollar companies

Every tech you mentioned is absolutely governed by multibillion dollar companies. Something like 75-85% of OSS code is contributed by employees doing their day job. Most Linux and Postgres contributions come from those same employees. HTTP and TCP/IP are managed by standard bodies and industry working groups that, you guessed it, are governed by multibillion dollar companies. Red Hat and IBM are responsible for 40-60% of contributions to Qemu.

Re: Bun's experimental Rust rewrite hits 99.8% test compatibility on Linux x64 glibc

#298
post #105

Earlier quoted context omitted.

cargo check reported over 16,000 compiler errors when I wrote that message. It could not print a version number or run JavaScript. I didn’t expect it to work this quickly and I also didn’t expect the performance to be as competitive. There’ll be a blog post with more details.

If this experiment ends up resulting in a real migration path, I think that would be completely awesome. Maybe it means we have a chance to revive older projects such as ngspice [0], but with modern affordances and better safety properties. From your post, though, it sounds like Bun may have been a pretty direct rewrite, without too many hard choices along the way. Is that fair? [0] https://ngspice.sourceforge.io/

[flagged]

Re: Bun's experimental Rust rewrite hits 99.8% test compatibility on Linux x64 glibc

#300
post #290
post #105

Earlier quoted context omitted.

cargo check reported over 16,000 compiler errors when I wrote that message. It could not print a version number or run JavaScript. I didn’t expect it to work this quickly and I also didn’t expect the performance to be as competitive. There’ll be a blog post with more details.

I think given the current mood of things, it would be prudent to not make such strong assertions on anything. Trust is in increasingly short supply these days.

Nothing Jarred said is an assertion other than "There’ll be a blog post with more details."
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