6 ms·

Bun 1.4

261 points by meetpateltech 1mo ago

deleted 1mo ago
[deleted]
cube00 1mo ago
It's weird their promotional video repeats "you can do <million things> without installing dependencies", if I want headless browser testing is that wrong to install a project that offers that? Why would I want everything reimplemented in this massive binary? Why would Bun be anymore in touch with nuances of all these different technologies then individual projects dedicated to their own speciality? JS Runtime, Package Manager, Test Runner (both unit and headless browser), Bundler, JSX, PosgreSQL/MySQL/SQLite drivers, S3 client, Redis client, Formatter, Linter, etc. Not to mention parsers for YAML, TOML, Markdown which are easily three separate projects worth of complexity in their own right. I guess one clear downside is to get all these great features they're pushing for 1.4 you needed to wait until everything was ready. Given 1.3 was pushed out in October 2025, a 10 month release cycle across so many large technologies is tough. Before you give a pass because of the Rust rewrite Bun 1.2 was released in January 2025 I have to respect Jarred knows how to work the algorithm, 10 carefully crafted X teaser posts for this release spaced out over 72 hours https://xcancel.com/jarredsumner https://xcancel.com/jarredsumner
- Jcampuzano2 1mo ago
  Its strange how flip floppy the JS ecosystem is, because go back literally 1-3 years or so and the BIGGEST complaint was the lack of a standard library and having to use a package for everything. But now that Bun is actually doing it its somehow bad? Its also still open source, so those implementations you mention need dedicated teams can still get the attention they need by the community if needed. I'm on the side that I'd actually prefer if node included more out of the box and we could drastically cut down on the number of packages we need due to the amount of supply chain attacks that happen on packages in the node ecosystem.
  - optionalsquid 1mo ago
    Is that flip-flopping or just different developers having different preferences? Those who complain now would have had no reason to complain back then, and vice versa
    - nozzlegear 1mo ago
      Also known as the Goomba fallacy: https://en.wiktionary.org/wiki/Goomba_fallacy https://en.wiktionary.org/wiki/Goomba_fallacy
    - nicoburns 1mo ago
      I'm pretty sure it's this. There's a genuine split in the developer community over this issue. And the JS community in particular is enormous.
  - pier25 1mo ago
    I agree and I also wish Node did more. Otoh should a standard lib give you absolutely everything? Probably not. There needs to be a line somewhere. Right now Bun’s policy on this seems to be "whatever Jarred feels like should be in there".
    - erlich 1mo ago
      > "whatever Jarred feels like should be in there" This is the main draw. Everything he implemented was fast and minimalist and he usually implements a standardized api (web apis, esbuild bundler api). The opinionated stuff is usually very common sense. Most of the libraries OC mentions are things you would just like to be as fast as possible above all else.
    - barnabee 1mo ago
      My line for exclusion from standard library is a library that’s any one of: - not obviously/generally useful (i.e. useless or too specific/should be a program not a library) - obviously trivial - already available (open source) elsewhere by a credible team that supporte and maintains it Anything else… put it in the stdlib
- tempaccount420 1mo ago
  It's faster to have it in the runtime in native code. You have more options, not less, you can still use the external dependencies.
- cnqso 1mo ago
  I personally do not feel limited by the ~100mb binary size. We're working in Javascript after all.
- preommr 1mo ago
  > Why would I want everything reimplemented in this massive binary? Why would Bun be anymore in touch with nuances of all these different technologies then individual projects dedicated to their own speciality? It's funny because the top article on HN is about a malicious rust crate package, and people keep making comparisons to js/npm and how both language suffer from frequent security issues because they have weak std libs.
  - andai 1mo ago
    I saw a post recently about how LLMs are much more effective in Ruby on Rails because it's batteries included, so you don't get so many implementation details crapping up the context window. I assume the same benefit applies to humans as well!
    - DanielHB 1mo ago
      I am not into the Ruby on Rails world, but I find LLMs much more effective with powerful type systems like Typescript. Especially if you nudge it to keep things strict and (statically) eliminate invalid states. Do they use similar systems (build-time typing) for Ruby? When the LLM can verify its own output by running static analysis they produce better results. They also seem to understand type definitions and avoid going to the source which, in theory, should reduce context size.
      - brandensilva 1mo ago
        Elixir started adding a type system as well after Typescript proved to greatly help AI feel confident in its output. So yeah others are catching on the importance of a type system to enforce that successful contract for AI agents.
    - CuriouslyC 1mo ago
      If agents are good at RoR, it's ironic because they're bad at Ruby. They aren't good at holding a model of the 20 different things various code you've loaded has monkey patched, no longer respecting their original contracts.
- maherbeg 1mo ago
  Some of these feel like solved problems effectively, so having them in the standard library is nice (at the expense of keeping these forever for backwards compatibility once a new tech replaces it). I do think having a larger standard library for common things (like golang) is the way to go. If a dependency seems to basically be installed by default everywhere, maybe it should go in the standard library.
- Aurornis 1mo ago
  > It's weird their promotional video repeats "you can do <million things> without installing dependencies", A couple years ago a common complaint was that the JavaScript ecosystem relied too heavily on dependencies for everything. Remember the left-pad incident where the developer deleted the popular dependency out of protest for reasons I can even remember? Or when colors.js was sabotaged to break everything that depended on it? The node-ipc package was sabotaged to delete files on developer’s machines. Then we had a wave of supply chain attacks that tried to insert malware into build scripts of popular dependencies. So the ecosystem started moving toward more batteries-included style development in response.
  - skydhash 1mo ago
    The complaint was micro-dependencies and huge sprawling trees. What was needed was quality dependencies on the level of SDL, ffmpeg, libcurl, where one domain is solved well and the focus is on API stability and good implementation. Not a battery included type of things.
- shimman 1mo ago
  I've still yet to run into any enterprise project using bun in the wild. It really feels like something entirely contained within startups that would choose wildly inappropriate tech like next.js. Add in the influencer dev brainrot culture and you get these VC backed efforts to privatized publicly important projects (node.js) under control of quite evil people that have zero record of helping others.
- bcye 1mo ago
  I always thought Bun's approach was to be the JS runtime with a large well-designed std-library, this isn't really new. It's nice to have a choice of a more or less-featured runtime depending on the project's requirements -- if size and complexity are an issue, there's a variety to choose from.
- pettijohn 1mo ago
  I for one prefer batteries-included. Decision fatigue for every cobbled together package takes its toll. Having a single, trustworthy, good-enough solution for so many things makes my life easier.
- ryankuykendall 1mo ago
  “ Why would I want everything reimplemented in this massive binary? “ This isn’t about what individual developers would want but what is most beneficial to Anthropic and claude code. They are likely using Bun as a vehicle for standardizing and enriching local user environments in order to address common tasks that claude generally writes bespoke scripts to accomplish.
- panzi 1mo ago
  Out of the things you mentioned I think the following make totally sense to be included in a language runtime like this: JavaScript runtime (obviously), package manager, test runner for unit tests, bundler, JSX, SQLite bindings, formatter, linter, YAML and TOML parsers. Maaaaybe even a Markdown parser and HTML5 parser. Definitely JSON, CSV and XML parsers. I.e. similar to Python. Though Python is a bit of an incoherent mess. If you have all these you need them to be coherent.
- ralusek 1mo ago
  Things like headless browsers are really annoying to include in FaaS environments, but are super useful. If they're in the runtime binary already, that'd be great.
- barnabee 1mo ago
  Ideally everything not built specifically for any given project is part of the OS or some other battle tested, supported system package. For example, I might well choose to reimplement eg a subset of TOML parsing to avoid the dependency risk. I don’t write JavaScript/TypeScript, but if I did, I’d find Bun’s “batteries included” approach compelling, at least to the extent I decide I can trust Bun, after due diligence
- tredre3 1mo ago
  > It's weird their promotional video repeats "you can do <million things> without installing dependencies" In 1.3 you couldn't even use the repl without downloading dependencies. In 1.4 it is now finally built-in, hurray! That alone is why I'm going to install 1.4. Finally a truly portable typescript repl.
- jamesnorden 1mo ago
  If you want Node just use Node, complaining that something else is not Node is crazy.
- dataplumb3r 1mo ago
  Some of these are situational, but many are expectations of a modern platform. Take Python - the standard lib now has things like a toml parser, sqlite client. And while I avoid the entire JS ecosystem as much as possible, a simple search to find a good Postgres client was not elucidating. https://wiki.postgresql.org/wiki/List_of_drivers https://wiki.postgresql.org/wiki/List_of_drivers two options - with node-postgres / pg seeming to be the most supported or postgres.js which has more abstractions but is less active Contrast that to the question for Java, where it's clear the official JDBC driver is the best option.
- vrighter 1mo ago
  it's because they were asking claude what features they should implement next. So we got everything and the kitchen sink
andsoitis 1mo ago
Congratulations to the Bun team!
- anony-123 1mo ago
  The team of AI bots :)
mjmas 1mo ago
This blog post / changelog is extremely long. Around 50 metres long on mobile.
- evolve2k 1mo ago
  [flagged]
  - hbn 1mo ago
    Is it slop if the product is working as intended? I don't use Bun, so I don't know if quality has degraded. But if it hasn't and they're shipping features users want faster than ever, I wouldn't call it slop. I don't care who wrote the code if the end product is working.
    - evolve2k 1mo ago
      We’re just three months in and already there’s plenty wobble. Bun 1.4 Rust rewrite is not looking good https://news.ycombinator.com/item?id=49357401 https://news.ycombinator.com/item?id=49357401
- neuronexmachina 1mo ago
  It's pretty long, but looking through it the text seems pretty streamlined. I think there's just a lot of changes.
- dyzone 1mo ago
  So what. Ask your claude to read it. You're on the $200 plan, right?
sunsetSamurai 1mo ago
I recently pivoted to Rust for the backend development, after getting tired of the nodejs ecosystem fragmentation and how fragile things feel. Bun seems very interesting since it allows you to do so many things without pulling in 3rd party libraries and bundlers? Is anybody using it instead of nodejs? how's the experience so far? I might have to give it a try. Yes, I know there's probably better options than Rust for building APIs, but I wanted to learn it, so why not?
- m00dy 1mo ago
  I always use Rust. You've made the right choice.
- christophilus 1mo ago
  I'm using it, though I'm leery of how the project is run. It's been great, to be honest. I have been able to build very low-dependency projects quite quickly. Bun's documentation is decent, and its underlying features are performant.
- jjice 1mo ago
  The most appealing thing of Go to me is the good batteries including tooling. I don't use it much outside of little personal projects where I really don't want to deal with dependencies and want a small binary.
  - arjie 1mo ago
    Yeah, I prefer Rust as a language but the ecosystem and toolchain is risky. E.g. build time scripts from upstream is too risky these days and it’s commonly used. Go is a good stdlib and trivial build toolchain. You just cargo build and all your apes gone.
  - theshrike79 1mo ago
    This has been my choice for a while too, especially when I found out that you can embed a full-ass webapp in a single executable. Backend + web API + the actual web pages all contained in a single file. If you have sane defaults, deploying is literally just copying a single executable over.
luciana1u 1mo ago
[flagged]
- hbn 1mo ago
  "Developing APIs is the process of building future regret." - Chet Haase
- brandensilva 1mo ago
  The cycle's will never gonna end. It's just gonna be incredibly faster now.
preommr 1mo ago
omfg, that's a long post. How is this even possible? I know we're all using AI, but Bun seems like the one singular project where there's just been a crazy increase in the amount of output, a 10x on the 10x. How are they doing this?
- christophilus 1mo ago
  Unlimited full-access to one of the best LLMs / agents on the market, and 80 hour work weeks probably.
  - cube00 1mo ago
    Also, access to models the public doesn't have, he had full Fable 5 in May. Jarred spins it as "pre-release" [1] but it was pre-embargo. [1]: https://bun.com/blog/bun-in-rust#loops-that-write-review-code:~:text=I%20used%20a%20pre%2Drelease%20version%20of%20Claude%20Fable%205%20for%20much%20of%20the%20Rust%20rewrite https://bun.com/blog/bun-in-rust#loops-that-write-review-cod....
    - aurareturn 1mo ago
      He likely had unlimited access to unrestricited Mythos in May, which is even better than Fable.
  - dolmen 1mo ago
    Agents have 168 hour work weeks.
timetraveller26 1mo ago
I, for one, don't welcome our new AI overlords
yomismoaqui 1mo ago
I like how the "over 10 MB smaller" is dubbed, sure the video was recorded some time ago and that number changed. https://youtu.be/i38DgEuaJwM?si=6oKAysKoRDPCihsL&t=176 https://youtu.be/i38DgEuaJwM?si=6oKAysKoRDPCihsL&t=176
suriyaG 1mo ago
This is awesome. slightly aside, but I find it worrying that our industry treats a lot of cannon events in stride and don't organize around that idea or to mitigate the risks around that idea. things that everybody basically just complained but ended up working out fine, - Bun rust rewrite. - Elon Musk firing 80% of twitter by stack ranking employees by code committed - autocompletion basically just taking over everyone maybe I'm just taking extremely outlier outcomes. but it is still fascinating to see people complain about how LLMs don't think
- mpalmer 1mo ago
  How are you deciding that either of these things worked out fine
  - solid_fuel 1mo ago
    Well if you ignore all the issues and declare victory, I think you’ll find it’s possible to decide anything is fine.
    - tialaramex 1mo ago
      Best to stand on an aircraft carrier, that really sells the message.
      - solid_fuel 1mo ago
        > Best to stand on an aircraft carrier, that really sells the message. Can't do that anymore though, they keep having "laundry fires".
    - suriyaG 1mo ago
      I really am curious about the issues that I'm ignoring twitter was a dumpster fire before and now it is (to me) less of a dumpster fire. so far it seems like the bun rewrite is going quite well. I haven't found any major issues since the merge despite, robobun being the top committer in the repo.
rwz 1mo ago
This is a huge win for Bun & Anthropic. I've been keeping an eye on Bun development cycle since they announced the Rust rewrite and the huge drama and backlash it generated. They seem to be proving the skeptics wrong with this release.
- iamsaitam 1mo ago
  What exactly has this update led this to be a "huge win"?
  - zapnuk 1mo ago
    The things stated in the announcement? Mainly node compatibility though more test coverage and different performance improvements.
  - rwz 1mo ago
    I fully AI-driven rewrite of a massive codebase from one language to another within a reasonable release-cycle has never been done before. There was a lot of sentiment around the lines of: - Bun is done for, it's all slop now - there's no way a fully AI-written codebase can work - Jarred is an idiot for trusting AI to rewrite the whole thing - they're never going to release this, there's going to be a billion of bugs This release proved all of this wrong. It also serves as a great advertisement of how capable Anthropic models and harness are to enable this.
    - AlexeyBelov 1mo ago
      I don't think this release definively proved all of this wrong, no.
      - kalcode 1mo ago
        That's true, it was when they stealthed released it in a application that millions use and no one noticed.
      - rwz 1mo ago
mpeg 1mo ago
Announcing that the SSR memory leak is gone as part of a product launch is wild.
- brandensilva 1mo ago
  If it was one memory leak, it would be meh in the fix list, but the fact they've announced that they've eliminated all memory leaks because of Rust in about eleven days that's what's wild to me. We are living in a new world when it comes in how software is prompted into existence.
classicposter 1mo ago
https://bsky.app/profile/jacob.gold/post/3msvjwys7lc2t https://bsky.app/profile/jacob.gold/post/3msvjwys7lc2t Hey, did the memory leak really solve with slop rewrite?
- TiredOfLife 1mo ago
  Memory leaks in Bun not in the javascript it runs
  - tialaramex 1mo ago
    [dead]
julenx 1mo ago
From the release video, something catching my attention: > In Bun 1.4, I rewrote Bun in Rust. [...] I did it in 11 days, using Claude Code, and wrote about how, in our blog. Everything else in the video is phrased as "we", and even the section in the blog post is "We rewrote Bun in Rust"[1]. There's no question Jarred did the work and deserves enormous credit for it. I just found the contrast interesting, because the video explicitly frames the rewrite as "I", whereas the rest of the release frames it as "we". [1] https://bun.com/blog/bun-v1.4#we-rewrote-bun-in-rust https://bun.com/blog/bun-v1.4#we-rewrote-bun-in-rust
- seabass 1mo ago
  I think this was to contrast with the multi-engineer effort the task would normally be.
ksec 1mo ago
While it has been used by Anthropic, the main question is if it works in other Bun's 1.3 production settings. Ignoring all the improvements, if it does work and no major bug or problems occurred, We are in for some management top down "Rewrite it in Rust" action over the next few years. And perhaps even worst, management will believe in Claude feed into Claude development. This isn't so much about Bun or Node.js any more. It is the battleground for AI and non-AI coding.
- aurareturn 1mo ago
  This isn't so much about Bun or Node.js any more. It is the battleground for AI and non-AI coding. There is no non-AI coding anymore. I guarantee you Node.js team is heavily using AI to make changes and debug.
  - jaredcwhite 1mo ago
    No non-AI coding anymore? I think not. https://handcraftedcode.org https://handcraftedcode.org
    - aurareturn 1mo ago
      Some people still make crafts by hand.
      - jaredcwhite 1mo ago
        Plenty of people on that list maintain serious production systems or open source projects in use by a wide variety of people. It's not just some nerds tinkering in their basement.
        aurareturn 1mo ago
        I don't doubt this is the case. Even if they're producing code by hand, surely they have LLM helpers by now. Coding agents have really only taken off in the last 10 months. So it is still early.
tumdum_ 1mo ago
I wonder what was total token cost of the rewrite.
- sroussey 1mo ago
  I think around $300-400k, but that does not include the github issue/pr/ci stuff that runs continuously, which could double or triple it. Somewhere, the first two weeks were said to be about $200k.
  - rane 1mo ago
    That total assumes API billing rates, which isn't what Anthropic pays for the inference. So I'm confused why people keep quoting that. It's not representative of what it'd cost for you either because you could use cheaper models.
    - vdfs 1mo ago
      Yeah, when you spend billions in infrastructure you get to save $300k occasionally
    - nicce 1mo ago
      > That total assumes API billing rates, which isn't what Anthropic pays for the inference. So I'm confused why people keep quoting that. It's not representative of what it'd cost for you either because you could use cheaper models. It is, because this rewrite was marketing for Claude. So it reflects the price for what other companies might need to pay if they want to rewrite something else with similar size.
- meetpateltech 1mo ago
  From the Rewriting Bun in Rust blog post: 5.9B uncached input tokens, 690M output tokens, 72B cached reads, came out to ~$165k at API pricing.
  - tumdum_ 1mo ago
    That was the initial work, but since then there was lots of work performed with LLMs.
deleted 1mo ago
[deleted]
curiousmindz 1mo ago
[flagged]
ar_lan 1mo ago
Am I the only one starting to get annoyed by Bun just due to all the surrounding drama? I was genuinely surprised this was an actual link about an update - my gut inclination opening that was Jarred probably decided to rewrite Bun to JavaScript to stay pure or something like that.
asT125 1mo ago
So this is kind of a systemd for web developers. All functionality is absorbed into a vibe coded, un-auditable black box. Maybe run it as process 1 in a future ClaudeOS.
- TiredOfLife 1mo ago
  The code is here https://github.com/oven-sh/bun/ https://github.com/oven-sh/bun/ go and audit all you want
  - blks 1mo ago
    The author didn’t care to himself, just merging enormous PRs with “lol” tweets about how github doesn’t display all the changes because there are too many. This is unmaintable mess, and the author himself is struggling already, given how he pushed the release date ten times.
    - tock 1mo ago
      > given how he pushed the release date ten times Jared has always done that. Thats not specific to this 1.4 release.
    - chamomeal 1mo ago
      It’s not maintainable by humans because there’s not a single human person who actually wrote any of it. But I guess it’s maintainable by LLMs. Which is part of the anthropic marketing
      - Timon3 1mo ago
        Most big projects aren't written by a single human, yet are perfectly maintainable by humans.
- dataplumb3r 1mo ago
  >All functionality is absorbed into a vibe coded, un-auditable black box. As opposed to the famously stable and robust JS ecosystem. Though it feels like the web tooling is thankfully moving away from JS/Node EG webpack in js => rspack (rust) typescript in typescript => typescript in go (the loss of bootstrapping is a bit sad but worth it)
rs_rs_rs_rs_rs 1mo ago
I am in awe at how good the llm rewrite to rust is, not a single issue when running claude code for months now.
mawadev 1mo ago
Why do these people look and talk so stiff in the video?
- mpalmer 1mo ago
  Was the idea to put a human face on the automated refactor? Can't say it's especially effective
  - atonse 1mo ago
    Bun has been doing release videos for years. There's no drama here to create.
- rs_rs_rs_rs_rs 1mo ago
  It's hard making videos. How about you make a video on something you published and see how you look?
  - mawadev 1mo ago
    [flagged]
    - rs_rs_rs_rs_rs 1mo ago
      Show us your video!
      - mawadev 1mo ago
        [flagged]
        TiredOfLife 1mo ago
        rs_rs_rs_rs_rs and me at least.
        internet2000 1mo ago
slowpoke-tail 1mo ago
For me, notably absent from the release changelog and accompanying YouTube video they were excited to trumpet in the blog back in July, and the claim (still) this took 11 days. It's August 20th.
- sionisrecur 1mo ago
  Yes, I'm fine with the AI rewrite, just don't claim it was done in 11 days when it actually took ~50.
  - rwz 1mo ago
    The rewrite part of get to functionally equivalent to the existing zig version in rust did in fact take 11 days based on the available data. When that was done, they spend some time on a ton of new features and hardening and bugfixing that the Rust rewrite enabled. This took additional time.
    - dolmen 1mo ago
      At the end of the 11 days, reviews raised much use of unsafe blocks. I guess this is much reduced by now, and the effort required on that front should not be rejected from being part of the migration.
      - theshrike79 1mo ago
        It _worked_ after the 11 day migration. Getting rid of unsafe blocks (Which were AFAIK partly a Zig inflicted thing) was just polish.
- voiper1 1mo ago
  Weird there's no information about that here. But if they went down in cpu usage and memory usage, removed a memory leak, and are MORE compliant with nodejs... it sounds like a MASSIVE success?
reducesuffering 1mo ago
Absolute crickets from the "there's no way LLM's can rewrite Bun to Rust this quickly, it's going to be buggy, it's marketing" crowd Comments here 3 months ago are quite something: https://news.ycombinator.com/item?id=48132488 https://news.ycombinator.com/item?id=48132488
- ThouYS 1mo ago
  The copium has run out it seems
- zem 1mo ago
  this is currently on the front page of lobsters, I saw it even before I saw the bun 1.4 release announcement https://tipiirai.com/writing/bun-rust-rewrite-worries https://tipiirai.com/writing/bun-rust-rewrite-worries
  - reducesuffering 1mo ago
    Lobste.rs is now flagging Bun 1.4 post as spam and comments are dismissing it as nothing, even as that blog post got much more discussion and piling on about the rewrite. Internet echo chambers are quite a problem. AI success and its immense implications are wreaking havoc on the ability of even intellectuals in HN and lobsters to face reality in front of them, even as their predictions become falsified again and again.
    - zem 1mo ago
      honestly, no opinions on bun either way, I was just pointing out that the pushback against the big bang AI rewrite is far from quieted down.
    - owebmaster 1mo ago
      > Internet echo chambers are quite a problem. AI success and its immense implications are wreaking havoc on the ability of even intellectuals in HN and lobsters to face reality in front of them, even as their predictions become falsified again and again. In this scenario, do you see yourself as an intellectual? In this case, one that is illuminated by the glory of AI. Or just looking for validation and not finding?
deleted 1mo ago
[deleted]
npn 1mo ago
I wonder how many posts in this thread are AI generated or shill posted. nobody ever reports that they installed it and ran it on production or something. personally I only use bun to replace yarn as script executor now. Used to follow it and tried to replace node server sveltkit runtime with bun, but it didn't work reliably so I stopped the experiment. it's too bad. when you are spoiled by crystal/go/rust written servers that consume 20MB-50MB ram only, seeing a nodejs server consume 400-500MB ram looks ridiculous bun was such an attractive option.
arj 1mo ago
Bun is still massive, my hobby attempt at smaller confined js/wasm https://github.com/arj03/seedkernel/ https://github.com/arj03/seedkernel/
deleted 1mo ago
[deleted]
CuriouslyC 1mo ago
Bun was pretty cool as a test runner with a lot of promise for back-end services in Node shops, but it burned me with arcane issues in production repeatedly, agents changed the economics of writing software, and being owned by anthropic is the final nail in the coffin.
arjie 1mo ago
This was an incredible demo for Claude. The runtime hosted Claude Code for months and I never saw the slightest issue. Wholly machine ported. Truly amazing.
- qdnaG 1mo ago
  And all the vibe code tests were against Claude? Let's port the Linux kernel and run all tests against a single application only!
- tomlockwood 1mo ago
  We're never going to know how much it cost and how many hours of engineering time it took behind the scenes.
  - pas 1mo ago
    GitHub commits, PRs and issues are public. even their recent buildkite CI logs are public. apparently there's some kind of automated differential fuzzer to discover Node.js incompatibilities, but probably that's behind the curtain. We might never know the exact dollars and cents amount, but we can make pretty well calibrated guesses.
    - tomlockwood 1mo ago
      I'd estimate based on those it cost at least a million bucks.
- lavezzi 1mo ago
  > The runtime hosted Claude Code for months and I never saw the slightest issue. but did others?
udbhavs 1mo ago
Hate to comment more on the drama, but it's only after watching Andrew Kelley's talk at Software Should Work [1] that I realized how philosophically different he is from Jarred and the broader SF AI/VC sphere. Here he is in a conference talking about agency, enshittification, and learning to deprogram from a deeply religious background and then using that experience of internal questioning to define his relationship with computers. And somehow, the programming language he made (that currently bans AI contributions outright) ended up being instrumental for a tool that's in the center of the whole craze, and doing Tony Hawk 900 aerial spins with agentic AI software rewrites under a frontier lab. I'm not commenting on the effectiveness of the rewrite, but it seems fascinating that for a moment Zig found itself at the intersection of two very different camps that the software world seems to be divided into. It seems in retrospect like a bomb waiting to go off even if they didn't jump ship to Rust! [1] https://www.youtube.com/watch?v=zLZwpH5lCD4 https://www.youtube.com/watch?v=zLZwpH5lCD4
- lproven 1mo ago
  A text version, for anyone else who dislikes video: https://andrewkelley.me/post/dont-take-black-pill.html https://andrewkelley.me/post/dont-take-black-pill.html
capitanazo77 1mo ago
Jarred looks a little like the logo which shows a great compromise with the company! thumbs up
yipinwong 1mo ago
> Bun is not 100% compatible with Node.js yet. In practice, much of the existing JavaScript ecosystem just works. I don't care about 100% compatibility. NodeJS is a standard but dead to me. I rather have faster feedback loop and less development/build/test time than worrying about Node.JS compatibility. Bun is the answer for my flow. --- Bun might as well promote itself as the total replacement of Node.JS, and I will still hop in.
- brandensilva 1mo ago
  Yeah, I'm more interested in them covering the majority of people's needs and use cases than I guess having a hundred percent compatibility with libraries I'll never use. I'd much rather it be a focus that I could run bun in serverless, sandbox, wasm, or workerd-like environments for agentic workflows where bun is the runtime to power additional functionality for AI agents. I assume this is why Anthropic purchased them beyond just a PR stunt and where the project is going.
jiangplus 1mo ago
I’m just very disappointed with Bun. With LLM, Bun can ship new features effortlessly and bundle many features directly into the runtime, which could be implemented by third-party libraries. While this is more convenient for Bun user, this development approach just steals the time-tested designs of these open-source libraries. By offering simplified bundled APIs, Bun diminishes the value of contribution on those libraries. As a general-purpose runtime, Bun cannot continously improve on every one of these domains in depth; it can only provide the most common functionality. When changes are needed, developers also cannot easily patch or customize the interfaces bundled with the Bun runtime itself. If Bun becomes widely adopted, its APIs could effectively become locked in. That would not be healthy for the ecosystem.
getpokedagain 1mo ago
Bun honestly seems cool. But this creepy ass intro video is icky.
stillpointlab 1mo ago
I wonder if Anthropic owning Bun will eventually lead to it being trained on in future versions of Claude. Claude is already pretty handy with Typescript, but with all of the built in libs in Bun I wonder if there is even more to squeeze out.
brodo 1mo ago
I'm just patiently waiting for Bun to lose momentum and for Node to pick up the best ideas from Bun. Takes a couple of years usually, but saves me two migrations.
thebillkidy 1mo ago
Amazing job to the team! We already tried it out and got -50% CPU and -60% Mem usage! https://scrydon.com/insights/2026/08/21/bun-1-4-at-scrydon/ https://scrydon.com/insights/2026/08/21/bun-1-4-at-scrydon/
- nathanbijnens 1mo ago
  Same team. Best part was how boring it was! Numbers are staging, equal windows, two RCs rather than one isolated variable - but every Bun service dropped in resource use!
nathanbijnens 1mo ago
[flagged]
rico735 1mo ago
If Bun weren't owned by Anthropic, wouldn't they now be a little screwed? Presumably no one at Bun will know their codebase as well as they used to (unless there was a lot more human review than they claim), and so they're tied to AI, no matter how much tokens cost in future. It feels anyone else doing this would also now be owned by Anthropic, just without the payment.

261 points by meetpateltech 1mo ago

deleted 1mo ago

[deleted]

It's weird their promotional video repeats "you can do <million things> without installing dependencies", if I want headless browser testing is that wrong to install a project that offers that? Why would I want everything reimplemented in this massive binary? Why would Bun be anymore in touch with nuances of all these different technologies then individual projects dedicated to their own speciality? JS Runtime, Package Manager, Test Runner (both unit and headless browser), Bundler, JSX, PosgreSQL/MySQL/SQLite drivers, S3 client, Redis client, Formatter, Linter, etc. Not to mention parsers for YAML, TOML, Markdown which are easily three separate projects worth of complexity in their own right. I guess one clear downside is to get all these great features they're pushing for 1.4 you needed to wait until everything was ready. Given 1.3 was pushed out in October 2025, a 10 month release cycle across so many large technologies is tough. Before you give a pass because of the Rust rewrite Bun 1.2 was released in January 2025 I have to respect Jarred knows how to work the algorithm, 10 carefully crafted X teaser posts for this release spaced out over 72 hours https://xcancel.com/jarredsumner https://xcancel.com/jarredsumner

Jcampuzano2 1mo ago
Its strange how flip floppy the JS ecosystem is, because go back literally 1-3 years or so and the BIGGEST complaint was the lack of a standard library and having to use a package for everything. But now that Bun is actually doing it its somehow bad? Its also still open source, so those implementations you mention need dedicated teams can still get the attention they need by the community if needed. I'm on the side that I'd actually prefer if node included more out of the box and we could drastically cut down on the number of packages we need due to the amount of supply chain attacks that happen on packages in the node ecosystem.
- optionalsquid 1mo ago
  Is that flip-flopping or just different developers having different preferences? Those who complain now would have had no reason to complain back then, and vice versa
  - nozzlegear 1mo ago
    Also known as the Goomba fallacy: https://en.wiktionary.org/wiki/Goomba_fallacy https://en.wiktionary.org/wiki/Goomba_fallacy
  - nicoburns 1mo ago
    I'm pretty sure it's this. There's a genuine split in the developer community over this issue. And the JS community in particular is enormous.
- pier25 1mo ago
  I agree and I also wish Node did more. Otoh should a standard lib give you absolutely everything? Probably not. There needs to be a line somewhere. Right now Bun’s policy on this seems to be "whatever Jarred feels like should be in there".
  - erlich 1mo ago
    > "whatever Jarred feels like should be in there" This is the main draw. Everything he implemented was fast and minimalist and he usually implements a standardized api (web apis, esbuild bundler api). The opinionated stuff is usually very common sense. Most of the libraries OC mentions are things you would just like to be as fast as possible above all else.
  - barnabee 1mo ago
    My line for exclusion from standard library is a library that’s any one of: - not obviously/generally useful (i.e. useless or too specific/should be a program not a library) - obviously trivial - already available (open source) elsewhere by a credible team that supporte and maintains it Anything else… put it in the stdlib
tempaccount420 1mo ago
It's faster to have it in the runtime in native code. You have more options, not less, you can still use the external dependencies.
cnqso 1mo ago
I personally do not feel limited by the ~100mb binary size. We're working in Javascript after all.
preommr 1mo ago
> Why would I want everything reimplemented in this massive binary? Why would Bun be anymore in touch with nuances of all these different technologies then individual projects dedicated to their own speciality? It's funny because the top article on HN is about a malicious rust crate package, and people keep making comparisons to js/npm and how both language suffer from frequent security issues because they have weak std libs.
- andai 1mo ago
  I saw a post recently about how LLMs are much more effective in Ruby on Rails because it's batteries included, so you don't get so many implementation details crapping up the context window. I assume the same benefit applies to humans as well!
  - DanielHB 1mo ago
    I am not into the Ruby on Rails world, but I find LLMs much more effective with powerful type systems like Typescript. Especially if you nudge it to keep things strict and (statically) eliminate invalid states. Do they use similar systems (build-time typing) for Ruby? When the LLM can verify its own output by running static analysis they produce better results. They also seem to understand type definitions and avoid going to the source which, in theory, should reduce context size.
    - brandensilva 1mo ago
      Elixir started adding a type system as well after Typescript proved to greatly help AI feel confident in its output. So yeah others are catching on the importance of a type system to enforce that successful contract for AI agents.
  - CuriouslyC 1mo ago
    If agents are good at RoR, it's ironic because they're bad at Ruby. They aren't good at holding a model of the 20 different things various code you've loaded has monkey patched, no longer respecting their original contracts.
maherbeg 1mo ago
Some of these feel like solved problems effectively, so having them in the standard library is nice (at the expense of keeping these forever for backwards compatibility once a new tech replaces it). I do think having a larger standard library for common things (like golang) is the way to go. If a dependency seems to basically be installed by default everywhere, maybe it should go in the standard library.
Aurornis 1mo ago
> It's weird their promotional video repeats "you can do <million things> without installing dependencies", A couple years ago a common complaint was that the JavaScript ecosystem relied too heavily on dependencies for everything. Remember the left-pad incident where the developer deleted the popular dependency out of protest for reasons I can even remember? Or when colors.js was sabotaged to break everything that depended on it? The node-ipc package was sabotaged to delete files on developer’s machines. Then we had a wave of supply chain attacks that tried to insert malware into build scripts of popular dependencies. So the ecosystem started moving toward more batteries-included style development in response.
- skydhash 1mo ago
  The complaint was micro-dependencies and huge sprawling trees. What was needed was quality dependencies on the level of SDL, ffmpeg, libcurl, where one domain is solved well and the focus is on API stability and good implementation. Not a battery included type of things.
shimman 1mo ago
I've still yet to run into any enterprise project using bun in the wild. It really feels like something entirely contained within startups that would choose wildly inappropriate tech like next.js. Add in the influencer dev brainrot culture and you get these VC backed efforts to privatized publicly important projects (node.js) under control of quite evil people that have zero record of helping others.
bcye 1mo ago
I always thought Bun's approach was to be the JS runtime with a large well-designed std-library, this isn't really new. It's nice to have a choice of a more or less-featured runtime depending on the project's requirements -- if size and complexity are an issue, there's a variety to choose from.
pettijohn 1mo ago
I for one prefer batteries-included. Decision fatigue for every cobbled together package takes its toll. Having a single, trustworthy, good-enough solution for so many things makes my life easier.
ryankuykendall 1mo ago
“ Why would I want everything reimplemented in this massive binary? “ This isn’t about what individual developers would want but what is most beneficial to Anthropic and claude code. They are likely using Bun as a vehicle for standardizing and enriching local user environments in order to address common tasks that claude generally writes bespoke scripts to accomplish.
panzi 1mo ago
Out of the things you mentioned I think the following make totally sense to be included in a language runtime like this: JavaScript runtime (obviously), package manager, test runner for unit tests, bundler, JSX, SQLite bindings, formatter, linter, YAML and TOML parsers. Maaaaybe even a Markdown parser and HTML5 parser. Definitely JSON, CSV and XML parsers. I.e. similar to Python. Though Python is a bit of an incoherent mess. If you have all these you need them to be coherent.
ralusek 1mo ago
Things like headless browsers are really annoying to include in FaaS environments, but are super useful. If they're in the runtime binary already, that'd be great.
barnabee 1mo ago
Ideally everything not built specifically for any given project is part of the OS or some other battle tested, supported system package. For example, I might well choose to reimplement eg a subset of TOML parsing to avoid the dependency risk. I don’t write JavaScript/TypeScript, but if I did, I’d find Bun’s “batteries included” approach compelling, at least to the extent I decide I can trust Bun, after due diligence
tredre3 1mo ago
> It's weird their promotional video repeats "you can do <million things> without installing dependencies" In 1.3 you couldn't even use the repl without downloading dependencies. In 1.4 it is now finally built-in, hurray! That alone is why I'm going to install 1.4. Finally a truly portable typescript repl.
jamesnorden 1mo ago
If you want Node just use Node, complaining that something else is not Node is crazy.
dataplumb3r 1mo ago
Some of these are situational, but many are expectations of a modern platform. Take Python - the standard lib now has things like a toml parser, sqlite client. And while I avoid the entire JS ecosystem as much as possible, a simple search to find a good Postgres client was not elucidating. https://wiki.postgresql.org/wiki/List_of_drivers https://wiki.postgresql.org/wiki/List_of_drivers two options - with node-postgres / pg seeming to be the most supported or postgres.js which has more abstractions but is less active Contrast that to the question for Java, where it's clear the official JDBC driver is the best option.
vrighter 1mo ago
it's because they were asking claude what features they should implement next. So we got everything and the kitchen sink

andsoitis 1mo ago

Congratulations to the Bun team!

anony-123 1mo ago
The team of AI bots :)

mjmas 1mo ago

This blog post / changelog is extremely long. Around 50 metres long on mobile.

evolve2k 1mo ago
[flagged]
- hbn 1mo ago
  Is it slop if the product is working as intended? I don't use Bun, so I don't know if quality has degraded. But if it hasn't and they're shipping features users want faster than ever, I wouldn't call it slop. I don't care who wrote the code if the end product is working.
  - evolve2k 1mo ago
    We’re just three months in and already there’s plenty wobble. Bun 1.4 Rust rewrite is not looking good https://news.ycombinator.com/item?id=49357401 https://news.ycombinator.com/item?id=49357401
neuronexmachina 1mo ago
It's pretty long, but looking through it the text seems pretty streamlined. I think there's just a lot of changes.
dyzone 1mo ago
So what. Ask your claude to read it. You're on the $200 plan, right?

sunsetSamurai 1mo ago

I recently pivoted to Rust for the backend development, after getting tired of the nodejs ecosystem fragmentation and how fragile things feel. Bun seems very interesting since it allows you to do so many things without pulling in 3rd party libraries and bundlers? Is anybody using it instead of nodejs? how's the experience so far? I might have to give it a try. Yes, I know there's probably better options than Rust for building APIs, but I wanted to learn it, so why not?

m00dy 1mo ago
I always use Rust. You've made the right choice.
christophilus 1mo ago
I'm using it, though I'm leery of how the project is run. It's been great, to be honest. I have been able to build very low-dependency projects quite quickly. Bun's documentation is decent, and its underlying features are performant.
jjice 1mo ago
The most appealing thing of Go to me is the good batteries including tooling. I don't use it much outside of little personal projects where I really don't want to deal with dependencies and want a small binary.
- arjie 1mo ago
  Yeah, I prefer Rust as a language but the ecosystem and toolchain is risky. E.g. build time scripts from upstream is too risky these days and it’s commonly used. Go is a good stdlib and trivial build toolchain. You just cargo build and all your apes gone.
- theshrike79 1mo ago
  This has been my choice for a while too, especially when I found out that you can embed a full-ass webapp in a single executable. Backend + web API + the actual web pages all contained in a single file. If you have sane defaults, deploying is literally just copying a single executable over.

luciana1u 1mo ago

[flagged]

hbn 1mo ago
"Developing APIs is the process of building future regret." - Chet Haase
brandensilva 1mo ago
The cycle's will never gonna end. It's just gonna be incredibly faster now.

preommr 1mo ago

omfg, that's a long post. How is this even possible? I know we're all using AI, but Bun seems like the one singular project where there's just been a crazy increase in the amount of output, a 10x on the 10x. How are they doing this?

christophilus 1mo ago
Unlimited full-access to one of the best LLMs / agents on the market, and 80 hour work weeks probably.
- cube00 1mo ago
  Also, access to models the public doesn't have, he had full Fable 5 in May. Jarred spins it as "pre-release" [1] but it was pre-embargo. [1]: https://bun.com/blog/bun-in-rust#loops-that-write-review-code:~:text=I%20used%20a%20pre%2Drelease%20version%20of%20Claude%20Fable%205%20for%20much%20of%20the%20Rust%20rewrite https://bun.com/blog/bun-in-rust#loops-that-write-review-cod....
  - aurareturn 1mo ago
    He likely had unlimited access to unrestricited Mythos in May, which is even better than Fable.
- dolmen 1mo ago
  Agents have 168 hour work weeks.

timetraveller26 1mo ago

I, for one, don't welcome our new AI overlords

yomismoaqui 1mo ago

I like how the "over 10 MB smaller" is dubbed, sure the video was recorded some time ago and that number changed. https://youtu.be/i38DgEuaJwM?si=6oKAysKoRDPCihsL&t=176 https://youtu.be/i38DgEuaJwM?si=6oKAysKoRDPCihsL&t=176

suriyaG 1mo ago

This is awesome. slightly aside, but I find it worrying that our industry treats a lot of cannon events in stride and don't organize around that idea or to mitigate the risks around that idea. things that everybody basically just complained but ended up working out fine, - Bun rust rewrite. - Elon Musk firing 80% of twitter by stack ranking employees by code committed - autocompletion basically just taking over everyone maybe I'm just taking extremely outlier outcomes. but it is still fascinating to see people complain about how LLMs don't think

mpalmer 1mo ago
How are you deciding that either of these things worked out fine
- solid_fuel 1mo ago
  Well if you ignore all the issues and declare victory, I think you’ll find it’s possible to decide anything is fine.
  - tialaramex 1mo ago
    Best to stand on an aircraft carrier, that really sells the message.
    - solid_fuel 1mo ago
      > Best to stand on an aircraft carrier, that really sells the message. Can't do that anymore though, they keep having "laundry fires".
  - suriyaG 1mo ago
    I really am curious about the issues that I'm ignoring twitter was a dumpster fire before and now it is (to me) less of a dumpster fire. so far it seems like the bun rewrite is going quite well. I haven't found any major issues since the merge despite, robobun being the top committer in the repo.

rwz 1mo ago

This is a huge win for Bun & Anthropic. I've been keeping an eye on Bun development cycle since they announced the Rust rewrite and the huge drama and backlash it generated. They seem to be proving the skeptics wrong with this release.

iamsaitam 1mo ago
What exactly has this update led this to be a "huge win"?
- zapnuk 1mo ago
  The things stated in the announcement? Mainly node compatibility though more test coverage and different performance improvements.
- rwz 1mo ago
  I fully AI-driven rewrite of a massive codebase from one language to another within a reasonable release-cycle has never been done before. There was a lot of sentiment around the lines of: - Bun is done for, it's all slop now - there's no way a fully AI-written codebase can work - Jarred is an idiot for trusting AI to rewrite the whole thing - they're never going to release this, there's going to be a billion of bugs This release proved all of this wrong. It also serves as a great advertisement of how capable Anthropic models and harness are to enable this.
  - AlexeyBelov 1mo ago
    I don't think this release definively proved all of this wrong, no.
    - kalcode 1mo ago
      That's true, it was when they stealthed released it in a application that millions use and no one noticed.
    - rwz 1mo ago

mpeg 1mo ago

Announcing that the SSR memory leak is gone as part of a product launch is wild.

brandensilva 1mo ago
If it was one memory leak, it would be meh in the fix list, but the fact they've announced that they've eliminated all memory leaks because of Rust in about eleven days that's what's wild to me. We are living in a new world when it comes in how software is prompted into existence.

classicposter 1mo ago

https://bsky.app/profile/jacob.gold/post/3msvjwys7lc2t https://bsky.app/profile/jacob.gold/post/3msvjwys7lc2t Hey, did the memory leak really solve with slop rewrite?

TiredOfLife 1mo ago
Memory leaks in Bun not in the javascript it runs
- tialaramex 1mo ago
  [dead]

julenx 1mo ago

From the release video, something catching my attention: > In Bun 1.4, I rewrote Bun in Rust. [...] I did it in 11 days, using Claude Code, and wrote about how, in our blog. Everything else in the video is phrased as "we", and even the section in the blog post is "We rewrote Bun in Rust"[1]. There's no question Jarred did the work and deserves enormous credit for it. I just found the contrast interesting, because the video explicitly frames the rewrite as "I", whereas the rest of the release frames it as "we". [1] https://bun.com/blog/bun-v1.4#we-rewrote-bun-in-rust https://bun.com/blog/bun-v1.4#we-rewrote-bun-in-rust

seabass 1mo ago
I think this was to contrast with the multi-engineer effort the task would normally be.

ksec 1mo ago

While it has been used by Anthropic, the main question is if it works in other Bun's 1.3 production settings. Ignoring all the improvements, if it does work and no major bug or problems occurred, We are in for some management top down "Rewrite it in Rust" action over the next few years. And perhaps even worst, management will believe in Claude feed into Claude development. This isn't so much about Bun or Node.js any more. It is the battleground for AI and non-AI coding.

aurareturn 1mo ago
This isn't so much about Bun or Node.js any more. It is the battleground for AI and non-AI coding. There is no non-AI coding anymore. I guarantee you Node.js team is heavily using AI to make changes and debug.
- jaredcwhite 1mo ago
  No non-AI coding anymore? I think not. https://handcraftedcode.org https://handcraftedcode.org
  - aurareturn 1mo ago
    Some people still make crafts by hand.
    - jaredcwhite 1mo ago
      Plenty of people on that list maintain serious production systems or open source projects in use by a wide variety of people. It's not just some nerds tinkering in their basement.
      - aurareturn 1mo ago
        I don't doubt this is the case. Even if they're producing code by hand, surely they have LLM helpers by now. Coding agents have really only taken off in the last 10 months. So it is still early.

tumdum_ 1mo ago

I wonder what was total token cost of the rewrite.

sroussey 1mo ago
I think around $300-400k, but that does not include the github issue/pr/ci stuff that runs continuously, which could double or triple it. Somewhere, the first two weeks were said to be about $200k.
- rane 1mo ago
  That total assumes API billing rates, which isn't what Anthropic pays for the inference. So I'm confused why people keep quoting that. It's not representative of what it'd cost for you either because you could use cheaper models.
  - vdfs 1mo ago
    Yeah, when you spend billions in infrastructure you get to save $300k occasionally
  - nicce 1mo ago
    > That total assumes API billing rates, which isn't what Anthropic pays for the inference. So I'm confused why people keep quoting that. It's not representative of what it'd cost for you either because you could use cheaper models. It is, because this rewrite was marketing for Claude. So it reflects the price for what other companies might need to pay if they want to rewrite something else with similar size.
meetpateltech 1mo ago
From the Rewriting Bun in Rust blog post: 5.9B uncached input tokens, 690M output tokens, 72B cached reads, came out to ~$165k at API pricing.
- tumdum_ 1mo ago
  That was the initial work, but since then there was lots of work performed with LLMs.

deleted 1mo ago

[deleted]

curiousmindz 1mo ago

[flagged]

ar_lan 1mo ago

Am I the only one starting to get annoyed by Bun just due to all the surrounding drama? I was genuinely surprised this was an actual link about an update - my gut inclination opening that was Jarred probably decided to rewrite Bun to JavaScript to stay pure or something like that.

asT125 1mo ago

So this is kind of a systemd for web developers. All functionality is absorbed into a vibe coded, un-auditable black box. Maybe run it as process 1 in a future ClaudeOS.

TiredOfLife 1mo ago
The code is here https://github.com/oven-sh/bun/ https://github.com/oven-sh/bun/ go and audit all you want
- blks 1mo ago
  The author didn’t care to himself, just merging enormous PRs with “lol” tweets about how github doesn’t display all the changes because there are too many. This is unmaintable mess, and the author himself is struggling already, given how he pushed the release date ten times.
  - tock 1mo ago
    > given how he pushed the release date ten times Jared has always done that. Thats not specific to this 1.4 release.
  - chamomeal 1mo ago
    It’s not maintainable by humans because there’s not a single human person who actually wrote any of it. But I guess it’s maintainable by LLMs. Which is part of the anthropic marketing
    - Timon3 1mo ago
      Most big projects aren't written by a single human, yet are perfectly maintainable by humans.
dataplumb3r 1mo ago
>All functionality is absorbed into a vibe coded, un-auditable black box. As opposed to the famously stable and robust JS ecosystem. Though it feels like the web tooling is thankfully moving away from JS/Node EG webpack in js => rspack (rust) typescript in typescript => typescript in go (the loss of bootstrapping is a bit sad but worth it)

rs_rs_rs_rs_rs 1mo ago

I am in awe at how good the llm rewrite to rust is, not a single issue when running claude code for months now.

mawadev 1mo ago

Why do these people look and talk so stiff in the video?

mpalmer 1mo ago
Was the idea to put a human face on the automated refactor? Can't say it's especially effective
- atonse 1mo ago
  Bun has been doing release videos for years. There's no drama here to create.
rs_rs_rs_rs_rs 1mo ago
It's hard making videos. How about you make a video on something you published and see how you look?
- mawadev 1mo ago
  [flagged]
  - rs_rs_rs_rs_rs 1mo ago
    Show us your video!
    - mawadev 1mo ago
      [flagged]
      - TiredOfLife 1mo ago
        rs_rs_rs_rs_rs and me at least.
      - internet2000 1mo ago

slowpoke-tail 1mo ago

For me, notably absent from the release changelog and accompanying YouTube video they were excited to trumpet in the blog back in July, and the claim (still) this took 11 days. It's August 20th.

sionisrecur 1mo ago
Yes, I'm fine with the AI rewrite, just don't claim it was done in 11 days when it actually took ~50.
- rwz 1mo ago
  The rewrite part of get to functionally equivalent to the existing zig version in rust did in fact take 11 days based on the available data. When that was done, they spend some time on a ton of new features and hardening and bugfixing that the Rust rewrite enabled. This took additional time.
  - dolmen 1mo ago
    At the end of the 11 days, reviews raised much use of unsafe blocks. I guess this is much reduced by now, and the effort required on that front should not be rejected from being part of the migration.
    - theshrike79 1mo ago
      It _worked_ after the 11 day migration. Getting rid of unsafe blocks (Which were AFAIK partly a Zig inflicted thing) was just polish.
voiper1 1mo ago
Weird there's no information about that here. But if they went down in cpu usage and memory usage, removed a memory leak, and are MORE compliant with nodejs... it sounds like a MASSIVE success?

reducesuffering 1mo ago

Absolute crickets from the "there's no way LLM's can rewrite Bun to Rust this quickly, it's going to be buggy, it's marketing" crowd Comments here 3 months ago are quite something: https://news.ycombinator.com/item?id=48132488 https://news.ycombinator.com/item?id=48132488

ThouYS 1mo ago
The copium has run out it seems
zem 1mo ago
this is currently on the front page of lobsters, I saw it even before I saw the bun 1.4 release announcement https://tipiirai.com/writing/bun-rust-rewrite-worries https://tipiirai.com/writing/bun-rust-rewrite-worries
- reducesuffering 1mo ago
  Lobste.rs is now flagging Bun 1.4 post as spam and comments are dismissing it as nothing, even as that blog post got much more discussion and piling on about the rewrite. Internet echo chambers are quite a problem. AI success and its immense implications are wreaking havoc on the ability of even intellectuals in HN and lobsters to face reality in front of them, even as their predictions become falsified again and again.
  - zem 1mo ago
    honestly, no opinions on bun either way, I was just pointing out that the pushback against the big bang AI rewrite is far from quieted down.
  - owebmaster 1mo ago
    > Internet echo chambers are quite a problem. AI success and its immense implications are wreaking havoc on the ability of even intellectuals in HN and lobsters to face reality in front of them, even as their predictions become falsified again and again. In this scenario, do you see yourself as an intellectual? In this case, one that is illuminated by the glory of AI. Or just looking for validation and not finding?

deleted 1mo ago

[deleted]

npn 1mo ago

I wonder how many posts in this thread are AI generated or shill posted. nobody ever reports that they installed it and ran it on production or something. personally I only use bun to replace yarn as script executor now. Used to follow it and tried to replace node server sveltkit runtime with bun, but it didn't work reliably so I stopped the experiment. it's too bad. when you are spoiled by crystal/go/rust written servers that consume 20MB-50MB ram only, seeing a nodejs server consume 400-500MB ram looks ridiculous bun was such an attractive option.

arj 1mo ago

Bun is still massive, my hobby attempt at smaller confined js/wasm https://github.com/arj03/seedkernel/ https://github.com/arj03/seedkernel/

deleted 1mo ago

[deleted]

CuriouslyC 1mo ago

Bun was pretty cool as a test runner with a lot of promise for back-end services in Node shops, but it burned me with arcane issues in production repeatedly, agents changed the economics of writing software, and being owned by anthropic is the final nail in the coffin.

arjie 1mo ago

This was an incredible demo for Claude. The runtime hosted Claude Code for months and I never saw the slightest issue. Wholly machine ported. Truly amazing.

qdnaG 1mo ago
And all the vibe code tests were against Claude? Let's port the Linux kernel and run all tests against a single application only!
tomlockwood 1mo ago
We're never going to know how much it cost and how many hours of engineering time it took behind the scenes.
- pas 1mo ago
  GitHub commits, PRs and issues are public. even their recent buildkite CI logs are public. apparently there's some kind of automated differential fuzzer to discover Node.js incompatibilities, but probably that's behind the curtain. We might never know the exact dollars and cents amount, but we can make pretty well calibrated guesses.
  - tomlockwood 1mo ago
    I'd estimate based on those it cost at least a million bucks.
lavezzi 1mo ago
> The runtime hosted Claude Code for months and I never saw the slightest issue. but did others?

udbhavs 1mo ago

Hate to comment more on the drama, but it's only after watching Andrew Kelley's talk at Software Should Work [1] that I realized how philosophically different he is from Jarred and the broader SF AI/VC sphere. Here he is in a conference talking about agency, enshittification, and learning to deprogram from a deeply religious background and then using that experience of internal questioning to define his relationship with computers. And somehow, the programming language he made (that currently bans AI contributions outright) ended up being instrumental for a tool that's in the center of the whole craze, and doing Tony Hawk 900 aerial spins with agentic AI software rewrites under a frontier lab. I'm not commenting on the effectiveness of the rewrite, but it seems fascinating that for a moment Zig found itself at the intersection of two very different camps that the software world seems to be divided into. It seems in retrospect like a bomb waiting to go off even if they didn't jump ship to Rust! [1] https://www.youtube.com/watch?v=zLZwpH5lCD4 https://www.youtube.com/watch?v=zLZwpH5lCD4

lproven 1mo ago
A text version, for anyone else who dislikes video: https://andrewkelley.me/post/dont-take-black-pill.html https://andrewkelley.me/post/dont-take-black-pill.html

capitanazo77 1mo ago

Jarred looks a little like the logo which shows a great compromise with the company! thumbs up

yipinwong 1mo ago

> Bun is not 100% compatible with Node.js yet. In practice, much of the existing JavaScript ecosystem just works. I don't care about 100% compatibility. NodeJS is a standard but dead to me. I rather have faster feedback loop and less development/build/test time than worrying about Node.JS compatibility. Bun is the answer for my flow. --- Bun might as well promote itself as the total replacement of Node.JS, and I will still hop in.

brandensilva 1mo ago
Yeah, I'm more interested in them covering the majority of people's needs and use cases than I guess having a hundred percent compatibility with libraries I'll never use. I'd much rather it be a focus that I could run bun in serverless, sandbox, wasm, or workerd-like environments for agentic workflows where bun is the runtime to power additional functionality for AI agents. I assume this is why Anthropic purchased them beyond just a PR stunt and where the project is going.

jiangplus 1mo ago

I’m just very disappointed with Bun. With LLM, Bun can ship new features effortlessly and bundle many features directly into the runtime, which could be implemented by third-party libraries. While this is more convenient for Bun user, this development approach just steals the time-tested designs of these open-source libraries. By offering simplified bundled APIs, Bun diminishes the value of contribution on those libraries. As a general-purpose runtime, Bun cannot continously improve on every one of these domains in depth; it can only provide the most common functionality. When changes are needed, developers also cannot easily patch or customize the interfaces bundled with the Bun runtime itself. If Bun becomes widely adopted, its APIs could effectively become locked in. That would not be healthy for the ecosystem.

getpokedagain 1mo ago

Bun honestly seems cool. But this creepy ass intro video is icky.

stillpointlab 1mo ago

I wonder if Anthropic owning Bun will eventually lead to it being trained on in future versions of Claude. Claude is already pretty handy with Typescript, but with all of the built in libs in Bun I wonder if there is even more to squeeze out.

brodo 1mo ago

I'm just patiently waiting for Bun to lose momentum and for Node to pick up the best ideas from Bun. Takes a couple of years usually, but saves me two migrations.

thebillkidy 1mo ago

Amazing job to the team! We already tried it out and got -50% CPU and -60% Mem usage! https://scrydon.com/insights/2026/08/21/bun-1-4-at-scrydon/ https://scrydon.com/insights/2026/08/21/bun-1-4-at-scrydon/

nathanbijnens 1mo ago
Same team. Best part was how boring it was! Numbers are staging, equal windows, two RCs rather than one isolated variable - but every Bun service dropped in resource use!

nathanbijnens 1mo ago

[flagged]

rico735 1mo ago

If Bun weren't owned by Anthropic, wouldn't they now be a little screwed? Presumably no one at Bun will know their codebase as well as they used to (unless there was a lot more human review than they claim), and so they're tied to AI, no matter how much tokens cost in future. It feels anyone else doing this would also now be owned by Anthropic, just without the payment.