alt Hacker NewsAnthropic acquires Bun
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This reads more like Anthropic wanted to hire Jarred and Jarred wants to work with AI rather than build a Saas product around bun. I doubt it has anything to do with what is best for bun the project. Considering bun always seemed to value performance more than all else, the only real way for them to continue pursuing that value would be to move into the actual js engine design. This seems like a good pivot for Jarred personally and likely a loss for bun.
> At the time of writing, Bun's monthly downloads grew 25% last month (October, 2025), passing 7.2 million monthly downloads. We had over 4 years of runway to figure out monetization. We didn't have to join Anthropic.
I believe this completely. They didn't have to join, which means they got a solid valuation.
> Instead of putting our users & community through "Bun, the VC-backed startups tries to figure out monetization" – thanks to Anthropic, we can skip that chapter entirely and focus on building the best JavaScript tooling.
I believe this a bit less. It'll be nice to not have some weird monetization shoved into bun, but their focus will likely shift a bit.
I’ll be honest, while I have my doubts about the match of interests and cohesion between an AI company and a JS runtime company I have to say this is the single best acquisition announcement blog post I’ve seen in 20 years or so.
Very direct, very plain and detailed. They cover all the bases about the why, the how, and what to expect. I really appreciate it.
Best of luck to the team and hopefully the new home will support them well.
As someone who have been using Deno for the last few years, is there anything that Bun does better? Bun seems to use a different runtime (JSC) which is less tested than V8, which makes me assume it might perform worse in real-world tasks (maybe not anymore?). The last time I checked Bun's source code, it was... quite messy and spaghetti-like, plus Zig doesn't really offer many safety features, so it's not that hard to write incorrect code. Zig does force some safety with ReleaseSafe IIRC, but it's still not the same as even modern C++, let alone Rust.
I'll admit I'm somewhat biased against Bun, but I'm honestly interested in knowing why people prefer Bun over Deno.
I wonder if this is a sign of AI companies trying to pivot?
> Bun will ship faster.
That'll last until FY 2027. This is an old lie that acquirers encourage the old owner to say because they have no power to enforce it, and they didn't actually say it so they're not on the hook. It's practically a cheesy pickup line, and given the context, it kinda is.
Anyone know how much Anthropic paid for Bun? I assume it was at least $26M, so Bun could break even and pay back its own investors, but I didn't see a number in the announcements from Anthropic or Bun.
My first thought went to how openai used Rust to build their CLI tool and Anthropic's CEO bought influence over Zig as a reaction.
I've seen a few of these seemingly random acquisitions lately, and I congratulate the companies and individuals that are acquired during this gold rush, but it definitely feels awkwardly artificial.
When I saw the headline I was ready to be mad, but after reading the post, I'm cautiously on board with this.
Bun is such a great runtime. If you haven't tried it, try it. It's got bells and whistles.
This will make sure Bun is around for many, many, years to come. Thanks Anthropic.
Why Bun?
Easy to setup and go. bun run <something.ts>
Bells and whistles. (SQL, Router, SPA, JSX, Bundling, Binaries, Streams, Sockets, S3)
Typescript Supported. (No need to tsc, bun can transpile for you)
Binary builds. (single executables for easy deployment)
Full Node.js Support. (The whole API)
Full NPM Support. (All the packages)
Native modules. (90% and getting better thanks to Zig's interop)
S3 File / SQL Builtin. (Blazingly Fast!)
You should try it. Yes, others do these things too, but we're talking about Bun.
Quote from the CEO of Anthropic in March 2025: "I think we'll be there in three to six months where AI is writing 90% of the code and then in 12 months we may be in a world where AI is writing essentially all of the code"
it boils down to - we didn't have full conviction that over the long run we will prove superior to node.js, however a.i company burning a lot of cash, has invested in us by basing their toolchain on us - so they have no option to acquire-hire us.
This acquisition makes no sense.
Investors must be happy because Bun never had to find out how to become profitable.
I'm confused. I installed claude code with:
npm install -g @anthropic-ai/claude-code
I don't really see how Bun fits as an acquisition for an AI company. This seems more like "we have tons of capital and we want to buy something great" than "Bun is essential to our core business model".
>If most new code is going to be written, tested, and deployed by AI agents
That perspective following “in two-three years” makes me shudder, honestly.
Curious about the deal value/price — any clues whether it was just to make existing investors even (so say up to $30M) or are we talking some multiple? But if it's a multiple, even 2x sounds a bit crazy.
I use Claude Code CLI daily - it's genuinely changed how I work. The $1B number sounds crazy but honestly tracks with how good the tool is. Curious how Bun integration will show up in practice beyond the native installer.
It's more honest than the Replicate answer but I think inevitably if you can't raise the next round and you get distracted by the shiny AI that this is the path taken by many teams. There is absolutely nothing wrong with that. There was an exuberant time when all the OSS things were getting funded, and now all AI things get funded. For many engineer founders, it's a better fit to go build deep technical stuff inside a bigger company. If I had that chance I would probably have taken it too. Good luck to the Bun team!
So Anthropic sees its CLI (in TypeScript) as the first-class product and maybe planning to expand the claude code with more JS based agents / ecosystem? Especially owning the runtime gives a lot of control over developer experience.
What is the business model behind open source projects like bun? How can a company "aquire" it and why does it do that?
In the article they write about the early days
We raised a $7 million seed round
I'm sure the Bun team will get Claude Code straightened out. Weird acquisition, but TBH Anthropic needed to fill this hole.
> I started porting esbuild's JSX & TypeScript transpiler from Go to Zig
How was Go involved there before Zig?
So many comments about reasoning here, yet none about the very obvious one, it's not stability of the infrastructure, it's future direction of a product like Claude Code. They need to know how to continue their optimisation machine to fit developers needs the best way possible (for good or for worse).
I guess we should wait for some opt-out telemetry some time soon. It'll be nothing too crazy at first, but we'll see how hungry they are for the data.
My long-term bet on Node being "boring" and "stable" continues to pay major dividends. So glad I never invested any time and effort on this ecosystem…
they acquihired the team and derisked their investment in building claude code on top of bun. makes sense to me.
moreover, now they can make investments in order to make it an an even more efficient and secure runtime for model workspaces.
This decision is honestly very confusing to me as a constant user of Claude Code (I have 3 of them open at the moment.)
So many of the issues with it seem to be because ... they wrote the damn thing in JavaScript?
Claude is pretty good at a constrained task with tests -- couldn't you just port it to a different language? With Claude?
And then just ... the huge claude.json which gets written on every message, like ... SQLite exists! Please, please use it! The scrollback! The Keyboard handling! Just write a simple Rust or Go or whatever CLI app with an actual database and reasonable TUI toolkit? Why double down and buy a whole JavaScript runtime?
A single bun? Is that really newsworthy?
Oh no ... unfortunately this likely means a Bun.AI API in my JS runtime.
Sounds like the goal is to bundle up Bun with Claude Code insanely tightly, to the point where it doesn't matter if you have nodejs installed locally, but also they can optimize key things for Claude Code's Bun runtime as needed. It's a brilliant acquisition, and bun stays open source, which allows it to continue to grow, to Anthropics benefit and everyone else's.
on the post they try to reassure the following question "If I bet my work project or company's tech stack on Bun, will it still be around in five or ten years?" and the thing is that we don't know if Anthropic itself will be around 5 to ten years
Congratulations to the bun team!
Interesting that this announcement is tied in with one for Claude Code revenue.
Feels like maybe AI companies are starting to feel the questions on their capital spending? They wanna show that this is a responsible acquisition.
why couldn't Anthropic simply use Claude Code to write Bun over the weekend??
What matters: it's staying open source and MIT licensed. I sincerely hope it stays that way. Congrats to the Bun team on making a great tool and getting the recognition they deserve.
> Being part of Anthropic gives Bun: Long-term stability.
Let's see. I don't want to always be the downer but the AI industry is in a state of rapid flux with some very strong economic headwinds. I wouldn't confidently say that hitching your wagon to AI gives you long term stability. But as long as the rest of us keep the ability to fork an open source project I won't complain too much.
(for those who are disappointed: this is why you stick with Node. Deno and Bun are both VC funded projects, there's only one way that goes. The only question is timeline)
This somewhat answers the question of "how on earth is a JS runtime company going to profit?"
This morning I found myself muttering something I won't repeat as a reaction to Claude Code's remarkably slow startup time.
Put the Bun folks directly on that please and nothing else.
Godspeed. Seems like a good pairing. Bun is sort of the only part of the JS ecosystem I like, and Code has become such an important tool for my work, that I think good things will come out of this match. Go Bundler as well.
So, we can anticipate that the new Anthropic browser will now have the interpreter Ken Thompson previewed for us 41-odd years ago?
Wouldn’t it make more sense to write the same functionality using a more performant, no-gc language? Aren’t competitors praised for their CLIs being faster for that reason?
In other news - Amp Code is a separate company now - https://ampcode.com/news/amp-inc
I’m curious to what the acquisition price was. Bun said they’ve raised $26 million so I’m assuming the price tag has to be a lot higher than that for investors to agree to an acquisition.
This announcement made me check in on the arbitrary code execution bug I reported that the Bun Claude bot created a PR for about 3 weeks ago:
https://github.com/oven-sh/bun/pull/24578
So far, someone from the bun team has left a bunch of comments like
> Poor quality code
...and all the tests still seem to be failing. I looked through the code that the bot had generated and to me (who to be fair is not familiar with the bun codebase) it looks like total dogshit.
But hey, maybe it'll get there eventually. I don't envy "taylordotfish" and the other bot-herders working at Oven though, and I hope they get a nice payout as part of this sale.
I don't get it. Why would Anthropic need to own a JS runtime?
I use bun in a project but Claude Code always uses node to run throwaway scripts. Maybe they can persuade it to use bun as part of this acquisition?
Bun has completely changed my outlook on the JS ecosystem. Prior to Bun, there was little focus on performance. Now the entire space rallies around it.
Congrats to Jarred and the team!
A lot of people seem confused about this acquisition because they think of Bun as a node.js compatible bundler / runtime and just compare it to Deno / npm. But I think its a really smart move if you think of where Bun has been pushing into lately which is a kind of cloud-native self contained runtime (S3 API, SQL, streaming, etc). For an agent like Claude Code this trajectory is really interesting as you are creating a runtime where your agent can work inside of cloud services as fluently as it currently does with a local filesystem. Claude will be able to leverage these capabilities to extend its reach across the cloud and add more value in enterprise use cases