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.
~3 months start to finish and the price of 1 engineer for a year, to rewrite a critical infra codebase that tens of millions of user software relies on. Truly the goalposts keep moving. This kind of project would've have been 10x the effort and price a few years 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
> 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.
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!
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.
I've read much of the same for Go. It's half true. Python doesn't have as many batteries but its common external packages are probably more present in training data than Go stdlib.
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.
Something that frustrates me about that discourse is that people argue about the mere existence of dependencies but all 'supply chain' (1) attacks are issues over when dependencies change. Dynamic systems are harder to reason about than static ones.
(1) scare quotes because I think it's dumb for us software people to call code we picked up on the side of the road part of a 'supply chain' like that means anything.
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.
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
I would guess that many devs' preference would be for a larger standard library, but not a kitchen sink.
Personally, I'd be happy with a larger suite of utility functions (say, most of Lodash / es-toolkit - remove the need for left-pad silliness), probably SQLite bindings (having a good persistence layer is great, it's perhaps the most robust and most widely deployed software on the planet), but not YAML (complex, security concerns, parser differences) or image handling (again, security concerns).
Node.js is, IMO, actually pretty good these days; they're regularly adding useful built-in tools that remove the need for add-on packages. (The ecosystem is so big that getting those updates to filter out is hard.)
There should be a space between "in the standard library" and "in a library written by some random person with a github account". An sqlite driver does not need to be bundled by the runtime, but it would be pretty great if there was an official sqlite driver library developed and supported by the node.js project but distributed through NPM.
I could argue that one implementation adding these things does not make a std library. You lose portability and fracture the ecosystem, which is probably one of their intentions
> 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.
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.
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.
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
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.
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.
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.
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.
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.
“ 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.
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?
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.
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.
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.
I use it heavily for personal use and find it works very well and lets me ship small applications quickly. I still use rust and other languages too as appropriate.
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.
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!
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.
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.
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.
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.
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
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.
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.
> 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.
Did you… perhaps read the entire comment you just posted? The crowd that was saying “no way they did that in 11 days” sure seems correct given that the release today is 3 months later. 3 months is longer than 11 days. Significantly so, in fact.
Be honest, though: had they shipped earlier—which they probably could have safely done—they would have been called “reckless” by the detractors. There was no way to make them happy here.
Perhaps. But they didn’t, instead they spent months claiming it was done, while maybe adding a bunch of new features (why? Get the base rewrite out first) which only made them look worse.
1.4 also adds a lot of features so its more than a port. Plus Claude Code has been using the rust port since atleast July 19. So its definitely less than 3 months.
Or, more likely, the amount of crappy auto generated code and “features” they crammed into this release resulted in so many bugs that a “simple rewrite” would up being 3 months of whack-a-mole with the issues they created. That’s the predictable result from the lack of engineering discipline involved here.
Not sure why people try so hard to interpret this in such a hostile way. It's very obvious that the 11 days were for the faithful, mechanical, agentic port, and then they followed up by commanding refactoring. The comments about the faithful port not being idiomatic rust are annoying
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.
> 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?
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.
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.
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
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.
claude code uses bun written rust. and it has been in prod for a month or so. I am finding it hard not to celebrate because it was quite literally a +1M -4K line change that is touching people today.
> irrespective of the political turmoil.
I was mostly concerned with the technical perspective of firing 80% of people by stack ranking. the consensus in HN at the time was that twitter had months left before all production systems burn down, because all the organizational knowledge has left. but seems like firing 80% went just fine for them. which I find fascinating.
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.
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.
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.
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".
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.
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.
Claude building stuff means a lot of things that everybody wanted to do, just couldn't allocate the attention or other resources - now get built.
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
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.
I assume the same benefit applies to humans as well!
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.
(1) scare quotes because I think it's dumb for us software people to call code we picked up on the side of the road part of a 'supply chain' like that means anything.
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.
https://en.wiktionary.org/wiki/Goomba_fallacy
Personally, I'd be happy with a larger suite of utility functions (say, most of Lodash / es-toolkit - remove the need for left-pad silliness), probably SQLite bindings (having a good persistence layer is great, it's perhaps the most robust and most widely deployed software on the planet), but not YAML (complex, security concerns, parser differences) or image handling (again, security concerns).
Node.js is, IMO, actually pretty good these days; they're regularly adding useful built-in tools that remove the need for add-on packages. (The ecosystem is so big that getting those updates to filter out is hard.)
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".
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.
- 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
I feel like nobody complained that you needed to install a dependency to do headless browser testing for example.
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.
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 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.
You have more options, not less, you can still use the external dependencies.
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
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.
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.
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.
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.
Yes, I know there's probably better options than Rust for building APIs, but I wanted to learn it, so why not?
Go is a good stdlib and trivial build toolchain.
You just cargo build and all your apes gone.
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.
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.
https://youtu.be/i38DgEuaJwM?si=6oKAysKoRDPCihsL&t=176
- Chet Haase
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
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.
How about you make a video on something you published and see how you look?
Maybe run it as process 1 in a future ClaudeOS.
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)
This is unmaintable mess, and the author himself is struggling already, given how he pushed the release date ten times.
Jared has always done that. Thats not specific to this 1.4 release.
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.
Comments here 3 months ago are quite something: https://news.ycombinator.com/item?id=48132488
> 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
Did you… perhaps read the entire comment you just posted? The crowd that was saying “no way they did that in 11 days” sure seems correct given that the release today is 3 months later. 3 months is longer than 11 days. Significantly so, in fact.
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?
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?
Jarred spins it as "pre-release" [1] but it was pre-embargo.
[1]: https://bun.com/blog/bun-in-rust#loops-that-write-review-cod....
Hey, did the memory leak really solve with slop rewrite?
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
What does that have to do with anything? They very clearly don't "think", that doesn't mean they can't be useful....
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.
twitter has (irrespective of the political turmoil etc.) purely as a technical product added more users, more features etc.
to me that seems like it worked out fine.
> irrespective of the political turmoil.
I was mostly concerned with the technical perspective of firing 80% of people by stack ranking. the consensus in HN at the time was that twitter had months left before all production systems burn down, because all the organizational knowledge has left. but seems like firing 80% went just fine for them. which I find fascinating.
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.
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.
> 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
This isn't so much about Bun or Node.js any more. It is the battleground for AI and non-AI coding.
The JVM and GCC have forbidden AI generated code. The world is bigger than you think.