I disagree with the overall premise: Before the acquisition, Bun had to figure out how to monetize at some point.
Now, even though their parent company does some shitty practices with their other software (claude code), it's a stretch to assume this will also translate into making Bun worse: Being worried makes sense but I remain optimistic about Bun.
Especially given the context of both of these different context: Claude Code is a gem of Anthropic, experiencing extreme growth and where any of its change can result in billing issues.
Bun is a JS runtime, and regardless of its growth, can focus on being the best runtime possible: It doesn't impact billing nor the bottom line of Anthropic, so they don't have to rush out patches due to abuse unlike CC.
It's unclear how it will pan out over the next years, still very early on the acquisition to see if anything will change, but I'm not concerned just yet.
> Now, even though their parent company does some shitty practices with their other software (claude code), it's a stretch to assume this will also translate into making Bun worse: Being worried makes sense but I remain optimistic about Bun.
Anthropic acquired Bun for their own benefit, to protect and grow their investment in Claude Code. Not for the benefit the JavaScript community at large. Sounds obvious but I guess that has to be pointed out. Outcomes will follow incentives in the long run.
> Before the acquisition, Bun had to figure out how to monetize at some point.
I think it is insane that people got into a situation where they had committed to a javascript runtime that had to "figure out how to monetize at some point". It is also bizarre that some people are still hopeful despite it being acquired by one of the most enormously unprofitable companies in the most enormously unprofitable sectors of our industry.
> I think it is insane that people got into a situation where they had committed to a javascript runtime that had to "figure out how to monetize at some point".
Why? What's the risk? It's open source. Also, speaking of open source, we are happy to commit to open source projects that have no monetization, nor any plans to ever monetize.
I know people say it is unprofitable but I wonder if there is a way to verify it is truly is.
I will not say any details but I worked for a giant company which was barely making money YoY but somehow the bonuses for heads were bigger and bigger given a proxy metric related to profit.
There are way too many ways companies arrange to pay themselves and never be profitable to avoid taxes.
"Profitable" is the wrong metric, really, it's whether it is sustainable - can development continue indefinitely given the current financial situation?
You might be underestimating the effect that corporate policies and culture have on the product.
Some teams have a push now to go all in on AI; don't even look at the code. I've seen this in action and the results are probably what you'd expect. Works great at some level, but as complexity accumulates (especially across a team with different "technical vocabularies"), the end result is compounding complexity and mistakes and no person or team knows how the software actually works.
No human testing of software or QA; unit + integration + give AI control over the browser/tool. Yes, this how some teams are moving forward now. So some of this may be that Anthropic's culture will end up causing shifts in how the Bun team operates and thinks.
If this type of culture and mindset becomes the norm, I think either the models have to get a lot better or the software quality is going to decline.
"Code is not cheap. Bad code is the most expensive it's ever been. Because if you have a codebase that's hard to change, you're not able to take advantage of all of the bounty that AI can offer. Because AI in a good codebase actually does really, really well."
Once bad code starts to compound on itself, it's going to be really hard to break out of it.
I don't disagree with the notion, but what is up with the dev community championing influencers that work no real jobs and just sell courses where they reread the docs to you at $500 a pop (this gent, $1k a pop)?
One favorable way to phrase it for Anthropic is they acquired Bun because CC and other internal tooling depended on it so heavily and they questioned it's future as purely OSS.
It remains to be seen how things will actually unfold.
> Now, even though their parent company does some shitty practices with their other software (claude code), it's a stretch to assume this will also translate into making Bun worse: Being worried makes sense but I remain optimistic about Bun.
Can you point to any examples of a company with shitty practices buying one without shitty practices that didn't end up with the shitty practices diffusing through the newly-acquired company within a couple of years?
Nope. The need to monotize and the fact that an acquihire cost some money is exactly why relying on a specific runtime is where people should have concern.
I agree with OP, and understand why to some it feels premature.
We live in a vastly different world than before, where people are more conscious of ethical concerns and willing to stand on their ground to avoid repeating past mistakes.
It might be premature from a tech standard, but it makes sense from an ethical concern. I don't think misconduct is as easily backtracked as it was before and preemptive measures are needed to avoid the large impact that those decisions make.
The author closes by enumerating some of the things they like about Bun which are not included in pnpm. The list is basically: native TS support, a vite-style bundler and a vitest/jest style test runner.
Other than a bundler, Node already has all of these. Different test runner syntax maybe but otherwise TS "just works" out of the box and their built in test runner is totally capable. Not sure I see the need for such a lament over Bun.
To be fair, Node didn't have any of these things until Deno & Bun challenged it. Deno didn't seem to move the needle by itself very much for whatever reason, but Bun's existence has had a tangible effect on the Node Technical Steering Committee. I would even argue that much of the current impetus has been driven by Jarred Sumner's savvy social media marketing. It got people talking, and Node is better because of it.
Additionally, Bun's push for covering as much of the Node API as possible has pushed Deno towards the same level of compatibility, and now most code is basically runtime agnostic. I'm not sure if I'll ever actually use Bun in production, but I'm glad it exists because the JavaScript ecosystem has been much improved simply due to its existence.
This is cool! But AFAIK bun promises to be a one-stop-shop for all your JS/TS dev needs, while Perry is "just" a compiler from Typescript to native executables.
OpenAI and Anthropic both are destined to doom for sure. There's no way around it and it is all in the math. Bun would be a causality. It is only a matter of time.
Only company that would survive the AI race - the one where the current wave was actually invented along with the research paper, the libraries and even specialised hardware: Google.
Google has a serious problem with its product management culture (long list of products and projects, people even skeptical of Flutter) otherwise they would have surpassed Anthropic long ago.
I still see no monetization with Bun and Deno to keep them going.
You see this all over the place with other programming languages.
The ones that have bleeding edge features do so, because there are companies, or universities (for their PhD and Msc thesis), that invest into those ecosystems.
In the end nodejs will keep improving, with Microsoft and Google's baking, and that will be it.
Bun is basically a wrapper over JSCore. I don't think it's that big of a feat. Furthermore they are heavily invested in vendor specific APIs which I think is not good.
pnpm is even worse. There is no way to bootstrap it without binary blobs making it an easy target supply chain attack waiting to happen that could hide in plain sight indefinitely.
But are you saying the harness is driving you insane? Or the model? Because Bun is,only the harness, and that part has been improving over time if you stay on the stable channel
Its the product overall, and its impossible to say where the issues are but I tend to think not the model since the changes seem to be able to occur overnight. So likely a combo of harness and service-layer.
I wonder why Anthropic chose to spend money on Bun when they could have easily spend that resource on Go which is fairly easy to use and fast. I'm sure their SWEs could easily everything things in Go. Anyone have insight on why?
Yeah, it's the same pattern you saw in the early react days where open source devs would try to "woo" the react core team into getting recognition to sell consulting services or courses.
The bun people likely have some fucked up incestial business relationship with some >dev manager at Anthropic and the same pattern is repeating. Only this cycle it's going straight to acquisitions, which honestly seems like a worse strategy and Anthropic will def can the bun engineers in less than <3 years or whenever they face an actual budget crunch that they can't stave off with more gulf money.
If I had to guess, it comes down to speed of iteration. Claude Code is built on JavaScript, so Bun aligns well with their current stack.
Switching to Go or Rust would only make sense if performance were the main priority, which doesn’t seem to be the case. Their current setup lets them ship quickly. A rewrite in Go would likely slow that down.
Codex moved to Rust, and you can see the trade-off. Performance improved, but release velocity dropped. They’re also still catching up to Claude Code, so they don’t face the same pressure to ship as fast.
My guess: JavaScript runs in the Browser as well as on the OS. That way you can train a model to be able to interact with both fairly simple. You can also see that their harness, claude-code is also written in js. So I guess they are quite invested in that language anyway.
One thing is sure. Claude has become terrible. Criticize any code Opus 4.7 created and it starts a blame game. Also. It denies that a version 4.7 even exists. Will look into moving back to ChatGPT that I quit because the mandatory spyware bs they added which I believe they nuked.
Does bun have a formal roadmap? I occasionally see some the changes that Jarred posts on X, and I wonder if they're really meaningful or not (perf improvements are always good). It also seems like a lot of the recent contributions are ai authored.
I tried using bun for a project earlier this year and learned that you can't use testcontainers(works fine w/ Deno).
I dont think so, but recent release includes a terminal markdown renderer built-in which means, even if handy, most of the focus is to make Claud Code great. I am not worried though, at least no yet.
Why did you have to stop using Cursor? I ask this as someone that uses Cursor, but recently at a conference I heard it referred to negatively several times - but in a very vague sense. I don't really have a dog in the fight, I'm using it because thats what the other dev I work with is using.
There is the SpaceX acquisition rumor, but that's not why.
I only use Cursor through the CLI, and while the UX of the CLI is pretty bad, I've found their harness (the prompts they use and orchestration of LLMs) to be nothing short of incredible. I can't comment on their agent development environment given I haven't spent a lot of time with it.
The reason I'm moving away from Cursor is cost. Unfortunately, if you want to use the SOTA models from both OpenAI and Anthropic you basically have to go direct through their subsidized plans.
I agree with your assessment that the harness is incredible and so I get a ton of mileage out of Auto + Composer 2. This is my workhorse.
Admittedly, with Opus 4.6+, GPT 5.5 I just haven't used them much and as I gain more experience I can see what the hype is all about. But to me, the answer isn't $200 max plan, it's bifurcating the work. Call me a spendthrift!
I personally switched back to vscode as I started using Claude and Opencode more for the AI flow, and I didn't see much added value any longer. Also, I was incredibly frustrated that they decided to hide the close button and finally, there were weird issues with editor groups spawning at unwanted times. They might be able to fix it, but I felt that they were starting to reach the limits of what you can do with a "live fork".
> Will we see issues start popping up in Bun that make it seem like the team doesn't even dogfood their own product? I don't know, but I'm not sure I want to continue using it just in case.
I sympathize with the general premise. The reaction to move away seems pre-mature though.
It sounds like `bun` is still performing just as well as before, and this sentiment isn't based on concrete changes. I also wouldn't expect infrastructure like `bun` to evolve in the way a consumer-facing product, especially one scaling as quickly as Claude Code, can.
I made this exact same decisions (bun -> pnpm) for similar reasons, mostly bc I didn’t like how haphazardly a core part of the stack was being vibe coded. Too many changes too quickly for something that’s supposed to be stable
Let them cook. Anything that they can do to get rid of the absolute hell that is dependencies in the JS ecosystem is worthwhile. I really don't care what they add as long as it's maintained
I’m confident that any unhappiness with Claude Code is at least 95% downstream of Anthropic seeing demand scale their revenue by ~3X in 6 months from a $multi-billion annual base.
Their product focus, roadmap, or execution is likely a rounding error in the face of that tsunami.
Frankly, it’s shocking they’re doing so well relative to, say, GitHub.
I still don't think Bun is production ready.
We just ripped bun out of a bunch of our production sevices. CPU runaway and memory leaks. All solved by switching back to nodejs.
I used to be a fan of Bun, but the way it keeps adding bloat makes me seriously doubt its future. Also, it seems like they are doing a lot of vibe coding without taking enough time, which raises other questions.
Node.js is also more stable, and it has started supporting TypeScript out of the box. I don’t think Bun will have many advantages after Node 26.
> and it has started supporting TypeScript out of the box
Node only does type stripping though. If you want proper TS support you still need a compiler.
> I don’t think Bun will have many advantages after Node 26
There are tons of advantages. For instance, Bun includes a lot of features that would need a third party dependency in Node: db driver, S3 client, watch mode, bundler, JSX support, etc.
Why would you want DB drivers and S3 clients in your runtime? That’s exactly what 3rd parties are for, you don’t want to have to update your runtime for a new version of your drivers
Mostly in my day to day routine, where is use Claude Code maybe 90% of the time, I don’t see that it’s become that bad. Yes they’ve made some questionable decisions on API usage and OpenClaw but I feel like this post is making it out to be worse than it is.
That being said I’ve been worried about the future of Bun anyway. Especially if the AI bubble pops. Then again, it’s open source.
The issues with Claude Code lately look to me like symptoms of being part of a service that is experiencing insane growth (fastest growth in history, by far [1]), while being severely constrained on adding capacity (GPUs are hard to get quickly right now, even if you have the money). I assume they're constantly fighting fires trying to keep the core use cases of Claude Code working, even if that means limiting OpenClaw usage in somewhat draconian ways.
It's annoying, but I don't see this as a bad thing at all for Bun.
No, all the issues are symptoms of trying to slop-code a functional product. Anthropic has admitted they dogfood heavily, and issues like [1] from the article could only be caused by a text generator.. I refuse to believe Anthropic employees are that stupid.
Aube[0] seems interesting to me, I have submitted it as show HN after hearing about your post. Its created by the same person who has made mise and I actually discovered it when I was browsing through on mise.en.dev website
I still use bun, but I think that there are some other pathways so I am not that worried about myself personally. But that's also because I most often than not code in golang rather than typescript/javascript
Personally, I suspect that Bun is a Silicon Valley attempt to lock some companies into its stack (similar to what cloud providers, Next.js + Vercel do). Especially now that Anthropic has become an owner, I'll be keeping Bun at a considerable distance.
The funniest part to me is that 10–15 years ago, companies were stuck in the development process due to binary (closed) dependencies. Now they're jumping into the same trap under a different name.
Maybe I’ve missed some scandals, but so far OpenJS Foundation is the best thing that has happened for the JavaScript ecosystem.
Now, even though their parent company does some shitty practices with their other software (claude code), it's a stretch to assume this will also translate into making Bun worse: Being worried makes sense but I remain optimistic about Bun.
Especially given the context of both of these different context: Claude Code is a gem of Anthropic, experiencing extreme growth and where any of its change can result in billing issues.
Bun is a JS runtime, and regardless of its growth, can focus on being the best runtime possible: It doesn't impact billing nor the bottom line of Anthropic, so they don't have to rush out patches due to abuse unlike CC.
It's unclear how it will pan out over the next years, still very early on the acquisition to see if anything will change, but I'm not concerned just yet.
Anthropic acquired Bun for their own benefit, to protect and grow their investment in Claude Code. Not for the benefit the JavaScript community at large. Sounds obvious but I guess that has to be pointed out. Outcomes will follow incentives in the long run.
I think it is insane that people got into a situation where they had committed to a javascript runtime that had to "figure out how to monetize at some point". It is also bizarre that some people are still hopeful despite it being acquired by one of the most enormously unprofitable companies in the most enormously unprofitable sectors of our industry.
Why? What's the risk? It's open source. Also, speaking of open source, we are happy to commit to open source projects that have no monetization, nor any plans to ever monetize.
There are way too many ways companies arrange to pay themselves and never be profitable to avoid taxes.
Some teams have a push now to go all in on AI; don't even look at the code. I've seen this in action and the results are probably what you'd expect. Works great at some level, but as complexity accumulates (especially across a team with different "technical vocabularies"), the end result is compounding complexity and mistakes and no person or team knows how the software actually works.
No human testing of software or QA; unit + integration + give AI control over the browser/tool. Yes, this how some teams are moving forward now. So some of this may be that Anthropic's culture will end up causing shifts in how the Bun team operates and thinks.
If this type of culture and mindset becomes the norm, I think either the models have to get a lot better or the software quality is going to decline.
Matt Pocock has a great talk here: https://youtu.be/v4F1gFy-hqg
Once bad code starts to compound on itself, it's going to be really hard to break out of it.One favorable way to phrase it for Anthropic is they acquired Bun because CC and other internal tooling depended on it so heavily and they questioned it's future as purely OSS.
It remains to be seen how things will actually unfold.
Can you point to any examples of a company with shitty practices buying one without shitty practices that didn't end up with the shitty practices diffusing through the newly-acquired company within a couple of years?
If you start seeing the people that created bun leaving Anthropic, then I'd probably start to worry. And I haven't seen any sign of that yet.
For me it's far from a stretch, in fact it matches closely a pattern that I've seen repeated many times over at this point.
We live in a vastly different world than before, where people are more conscious of ethical concerns and willing to stand on their ground to avoid repeating past mistakes.
It might be premature from a tech standard, but it makes sense from an ethical concern. I don't think misconduct is as easily backtracked as it was before and preemptive measures are needed to avoid the large impact that those decisions make.
Other than a bundler, Node already has all of these. Different test runner syntax maybe but otherwise TS "just works" out of the box and their built in test runner is totally capable. Not sure I see the need for such a lament over Bun.
Additionally, Bun's push for covering as much of the Node API as possible has pushed Deno towards the same level of compatibility, and now most code is basically runtime agnostic. I'm not sure if I'll ever actually use Bun in production, but I'm glad it exists because the JavaScript ecosystem has been much improved simply due to its existence.
https://nodejs.org/en/blog/release/v23.6.0
[1]: https://github.com/PerryTS/perry
Only company that would survive the AI race - the one where the current wave was actually invented along with the research paper, the libraries and even specialised hardware: Google.
Google has a serious problem with its product management culture (long list of products and projects, people even skeptical of Flutter) otherwise they would have surpassed Anthropic long ago.
You see this all over the place with other programming languages.
The ones that have bleeding edge features do so, because there are companies, or universities (for their PhD and Msc thesis), that invest into those ecosystems.
In the end nodejs will keep improving, with Microsoft and Google's baking, and that will be it.
Might as well just open our pants and wave our wangers, hoping for a better world
They are not a runtime, but they do seem to be interested in wrapping a lot of tools with simple top-level commands
The bun people likely have some fucked up incestial business relationship with some >dev manager at Anthropic and the same pattern is repeating. Only this cycle it's going straight to acquisitions, which honestly seems like a worse strategy and Anthropic will def can the bun engineers in less than <3 years or whenever they face an actual budget crunch that they can't stave off with more gulf money.
Switching to Go or Rust would only make sense if performance were the main priority, which doesn’t seem to be the case. Their current setup lets them ship quickly. A rewrite in Go would likely slow that down.
Codex moved to Rust, and you can see the trade-off. Performance improved, but release velocity dropped. They’re also still catching up to Claude Code, so they don’t face the same pressure to ship as fast.
What are the options in Go for cross-platforms GUI apps or running client-side in the browser?
I tried using bun for a project earlier this year and learned that you can't use testcontainers(works fine w/ Deno).
I only use Cursor through the CLI, and while the UX of the CLI is pretty bad, I've found their harness (the prompts they use and orchestration of LLMs) to be nothing short of incredible. I can't comment on their agent development environment given I haven't spent a lot of time with it.
The reason I'm moving away from Cursor is cost. Unfortunately, if you want to use the SOTA models from both OpenAI and Anthropic you basically have to go direct through their subsidized plans.
Admittedly, with Opus 4.6+, GPT 5.5 I just haven't used them much and as I gain more experience I can see what the hype is all about. But to me, the answer isn't $200 max plan, it's bifurcating the work. Call me a spendthrift!
Otherwise if you are looking for and IDE first approach with great AI integration it's the best product out there. I prefer it over CC/Codex.
Always appreciated nuance.
I sympathize with the general premise. The reaction to move away seems pre-mature though.
It sounds like `bun` is still performing just as well as before, and this sentiment isn't based on concrete changes. I also wouldn't expect infrastructure like `bun` to evolve in the way a consumer-facing product, especially one scaling as quickly as Claude Code, can.
Plus it’s not a huge lift right now
If Bun stays great, you saved yourself some time for switching, and got to keep using Bun.
If Bun worsens, you spend the same time for switching, just moved a bit later, and got to use Bun for a little longer.
For my projects I don’t even need any additional dependencies. I use vanilla dom and sqlite
Personally my experience with Bun has been 100% positive so far.
I'm aware full Node support is not there yet and may never happen but with dependencies that support Bun it's been a smooth ride for me.
Their product focus, roadmap, or execution is likely a rounding error in the face of that tsunami.
Frankly, it’s shocking they’re doing so well relative to, say, GitHub.
Node.js is also more stable, and it has started supporting TypeScript out of the box. I don’t think Bun will have many advantages after Node 26.
Node only does type stripping though. If you want proper TS support you still need a compiler.
> I don’t think Bun will have many advantages after Node 26
There are tons of advantages. For instance, Bun includes a lot of features that would need a third party dependency in Node: db driver, S3 client, watch mode, bundler, JSX support, etc.
That being said I’ve been worried about the future of Bun anyway. Especially if the AI bubble pops. Then again, it’s open source.
It's annoying, but I don't see this as a bad thing at all for Bun.
[1] https://www.axios.com/2026/04/13/anthropic-revenue-growth-ai
[1] https://youtu.be/J8O9LLpJNrg?t=1201
I still use bun, but I think that there are some other pathways so I am not that worried about myself personally. But that's also because I most often than not code in golang rather than typescript/javascript
[0]: https://aube.en.dev/
The funniest part to me is that 10–15 years ago, companies were stuck in the development process due to binary (closed) dependencies. Now they're jumping into the same trap under a different name.
Maybe I’ve missed some scandals, but so far OpenJS Foundation is the best thing that has happened for the JavaScript ecosystem.