Live data from Hacker News

How is the Bun rewrite in Rust going?

lockwood.dev

21–30 of 412 posts

Re: How is the Bun rewrite in Rust going?

#21

I didn't follow the thing too closely when it happened. Sure, I was aware of the big picture. But wow, I didn't expect that after all this noise there still hasn't been a release? That's just crazy to me. I shouldn't be surprised though, of course. Giving any credit or slack to a high-valuation LLM company is a silly endeavor.

[deleted]

Re: How is the Bun rewrite in Rust going?

#22
post #14
post #7

This post doesn’t make sense. It was rewritten in Rust. The rewrite itself is complete (no more Zig). Various people have claimed that Bun in Zig had a lot of tech debt. If they’re to be believed, it seems natural to assume the rewrite does, too. Perhaps all this activity is paying down some of that debt.

bun in zig was used by many companies. some were using it in prod. how many of those are using it in prod? none, because bun in rust is not released yet. Hence, the author concludes that rust rewrite is not complete as bun in rust is not released yet. I agree with author's POV.

The rust version is being used by Claude Code though - which is a fairly large product!

I was hoping for more push back against https://bun.com/blog/bun-in-rust - which is pretty thorough and has some decent arguments and reasoning for why they did the rewrite.

Re: How is the Bun rewrite in Rust going?

#24
post #14

Earlier quoted context omitted.

bun in zig was used by many companies. some were using it in prod. how many of those are using it in prod? none, because bun in rust is not released yet. Hence, the author concludes that rust rewrite is not complete as bun in rust is not released yet. I agree with author's POV.

The rust version is being used by Claude Code though - which is a fairly large product! I was hoping for more push back against https://bun.com/blog/bun-in-rust - which is pretty thorough and has some decent arguments and reasoning for why they did the rewrite.

I think they meant “released and available for use” rather than just out in the wild.

Re: How is the Bun rewrite in Rust going?

#25

Many repeat the point of “$165k is cheaper than team of multiple engineers working on the rewrite for a year”, which I think is flawed — the team of engineers would have produced idiomatic rust, and it would take probably 100k+ of tokens more to make the bun in rust idiomatic rust.

I feel your estimate of tokens is a few orders of magnitude off, it’s on the low side. I use more (albeit cached) when centering a div.

I think they missed a $ sign, i.e. they meant $100k of tokens

Re: How is the Bun rewrite in Rust going?

#26

I'm not sure how much insight we can glean from looking at the number of commits and release cadence here. In the aftermath of such a major refactor/rewrite, I would expect it to take some time to get back up to their usual development speed. Jared and the other developers are new to the Rust codebase, even if the structure is largely familiar. They're also likely focusing on other priorities right now such as tracki…

They also have made a release, in a sense, since they moved all Claude code users to it a month ago. (And apparently no one noticed).

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

Re: How is the Bun rewrite in Rust going?

#27
post #14

Earlier quoted context omitted.

bun in zig was used by many companies. some were using it in prod. how many of those are using it in prod? none, because bun in rust is not released yet. Hence, the author concludes that rust rewrite is not complete as bun in rust is not released yet. I agree with author's POV.

The rust version is being used by Claude Code though - which is a fairly large product! I was hoping for more push back against https://bun.com/blog/bun-in-rust - which is pretty thorough and has some decent arguments and reasoning for why they did the rewrite.

Yeah, but it's a TUI that has more bugs and worse performance than any other TUI in history. It's not like we'd notice a user after free.

Re: How is the Bun rewrite in Rust going?

#28

Many repeat the point of “$165k is cheaper than team of multiple engineers working on the rewrite for a year”, which I think is flawed — the team of engineers would have produced idiomatic rust, and it would take probably 100k+ of tokens more to make the bun in rust idiomatic rust.

I feel your estimate of tokens is a few orders of magnitude off, it’s on the low side. I use more (albeit cached) when centering a div.

100k tokens is your pre-prompt and your CLAUDE.md as well as a few files from your root.

Re: How is the Bun rewrite in Rust going?

#29

I'm not sure how much insight we can glean from looking at the number of commits and release cadence here. In the aftermath of such a major refactor/rewrite, I would expect it to take some time to get back up to their usual development speed. Jared and the other developers are new to the Rust codebase, even if the structure is largely familiar. They're also likely focusing on other priorities right now such as tracki…

Author here: I'm also not sure how much we can glean from any of that!!! I look forward to Anthropic or Bun releasing a retrospective after their next release that fully outlines the cost.
Post reply on HN