Is this the project announced a week or two ago by an AI company claiming they had built a browser but it turned out to be a crappy wrapper around Servo that didn’t even build? Or is this another one? I thought it was Anthropic but this says Cursor.
It is the same project, but my impression is that HN exaggerated many of the issues with it.
For example:
- They did eventually get it to build. Unknown to me: were the agents working on it able to build it, or were they blindly writing code? The codebase can't have been _that_ broken since it didn't take long for them to get it buildable, and they'd produced demo screenshots before that.
- It had a dependency on QuickJS, but also a homegrown JS implementation; apparently (according to this post) QuickJS was intended as a placeholder. I have no idea which, if either, ended up getting used, though I suspect it may not even matter for the static screenshots they were showing off (the sites may not have required JS to show that).
- Some of the dependencies (like Skia and HarfBuzz) are libraries that other browsers also depend on and are not part of browser projects themselves.
- Other dependencies probably shouldn't have been used, but they only represent a fraction of what a browser has to do.
However…
What I don't know, and seemingly nobody else knows, is how functional the rest of the codebase is. It's apparently very slow and fails to render most websites. But is this more like "lots of bugs, but a solid basis", or is it more like "cargo-culted slop; even the stuff that works only works by chance"? I hope someone investigates.
"Your scientists were so preoccupied with whether or not they could, they didn’t stop to think if they should."
I'm curious what is the energy/environmental/financial impact of this "research" effort of cobbling together a browser based on AI model that had been trained on freely available source code of existing browsers.
I can't imagine this browser being used outside of tinkering or curiosity toy - so the purpose of the research is just to see whether you can run absurd amount of agents simultaneously and produce something that somewhat works?
>I can't imagine this browser being used outside of tinkering or curiosity toy - so the purpose of the research is just to see whether you can run absurd amount of agents simultaneously and produce something that somewhat works?
> FastRender may not be a production-ready browser, but it represents over a million lines of Rust code, written in a few weeks, that can already render real web pages to a usable degree
I feel that we continue to miss the forest for the trees. Writing (or generating) a million lines of code in Rust should not count as an achievement in and of itself. What matters is whether those lines build, function as expected (especially in edge cases) and perform decently. As far as I can tell, AI has not been demonstrated to be useful yet at those three things.
simonw, I find it almost shocking how you had the chance to talk directly with the engineer who built this, and even when he directly says things that contradict what Cursor's own CEO said, you didn't push back a single iota.
Is the takeaway here that it's fine for a CEO to claim "it even has a custom JS VM!" on Twitter/X, then afterwards the engineer explains: "The JavaScript engine isn’t working yet" and "the agents decided to pause it", and this is all OK? Not a single pushback about this very obvious contradiction? This is just one example of many, and again, since it seems to be repeated: no, no one thinks this was supposed to rival Chrome, what a trite way of trying to change the narrative.
I understand you don't want to spook future potential interviewees, but damn if that didn't feel like you suddenly are trying to defend Cursor here, instead of being curious about what actually happened. It doesn't feel curious, it feels like we're all giving up the fight against unneeded hype, exaggeration and degradation of quality.
What happened with balanced perspectives, where we don't just take people for their words, and when we notice something is off, we bring it up?
On a separate note, I actually emailed Wilson Lin too, asking if I could ask questions about it. While he initially accepted, I never actually received any answers. I'm glad to you were able to get someone from Cursor to clarify a bit at least, even though we're still just scratching the surface. I just wish we had a bit more integrity in the ecosystem and community I guess.
The reaction to this would have been different two or three years ago but it looks extremely lame when you open January 2026 hackernews and this is the kind of thing a tech company is trying to persuade you into thinking is exciting or useful.
You've heard about what people are doing in the medical industry. Using AI to accelerate diagnosis and analysis of biological material. In astronomy it's showing us things that no human had ever seen before. You hear about all these things changing the world at large and the smaller worlds of individual people and families.
Then you look at the actual IT industry and we've got... some premade libraries duct taped together into a crappy browser that barely works. Of course when the value of this is compared to the cost, the response is that it's fine because it was never actually intended to be useful in the first place. Well we're actually a step ahead of you there.
The phrase "high on their own supply" describes all the people involved in this very well. I assure you we understand the goal of this project perfectly. It just wasn't a good, worthy, or even interesting goal. The immense amount of resources that went into this should have gone into something better. That's all there is to it.
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[ 2.3 ms ] story [ 31.2 ms ] threadFor example:
- They did eventually get it to build. Unknown to me: were the agents working on it able to build it, or were they blindly writing code? The codebase can't have been _that_ broken since it didn't take long for them to get it buildable, and they'd produced demo screenshots before that.
- It had a dependency on QuickJS, but also a homegrown JS implementation; apparently (according to this post) QuickJS was intended as a placeholder. I have no idea which, if either, ended up getting used, though I suspect it may not even matter for the static screenshots they were showing off (the sites may not have required JS to show that).
- Some of the dependencies (like Skia and HarfBuzz) are libraries that other browsers also depend on and are not part of browser projects themselves.
- Other dependencies probably shouldn't have been used, but they only represent a fraction of what a browser has to do.
However…
What I don't know, and seemingly nobody else knows, is how functional the rest of the codebase is. It's apparently very slow and fails to render most websites. But is this more like "lots of bugs, but a solid basis", or is it more like "cargo-culted slop; even the stuff that works only works by chance"? I hope someone investigates.
I'm curious what is the energy/environmental/financial impact of this "research" effort of cobbling together a browser based on AI model that had been trained on freely available source code of existing browsers.
I can't imagine this browser being used outside of tinkering or curiosity toy - so the purpose of the research is just to see whether you can run absurd amount of agents simultaneously and produce something that somewhat works?
Yes but this is a very interesting question IMO
> Any sufficiently complicated AI orchestration system contains an ad hoc, informally-specified, bug-ridden, slow implementation of half of Gas Town.
I feel that we continue to miss the forest for the trees. Writing (or generating) a million lines of code in Rust should not count as an achievement in and of itself. What matters is whether those lines build, function as expected (especially in edge cases) and perform decently. As far as I can tell, AI has not been demonstrated to be useful yet at those three things.
Is the takeaway here that it's fine for a CEO to claim "it even has a custom JS VM!" on Twitter/X, then afterwards the engineer explains: "The JavaScript engine isn’t working yet" and "the agents decided to pause it", and this is all OK? Not a single pushback about this very obvious contradiction? This is just one example of many, and again, since it seems to be repeated: no, no one thinks this was supposed to rival Chrome, what a trite way of trying to change the narrative.
I understand you don't want to spook future potential interviewees, but damn if that didn't feel like you suddenly are trying to defend Cursor here, instead of being curious about what actually happened. It doesn't feel curious, it feels like we're all giving up the fight against unneeded hype, exaggeration and degradation of quality.
What happened with balanced perspectives, where we don't just take people for their words, and when we notice something is off, we bring it up?
On a separate note, I actually emailed Wilson Lin too, asking if I could ask questions about it. While he initially accepted, I never actually received any answers. I'm glad to you were able to get someone from Cursor to clarify a bit at least, even though we're still just scratching the surface. I just wish we had a bit more integrity in the ecosystem and community I guess.
You've heard about what people are doing in the medical industry. Using AI to accelerate diagnosis and analysis of biological material. In astronomy it's showing us things that no human had ever seen before. You hear about all these things changing the world at large and the smaller worlds of individual people and families.
Then you look at the actual IT industry and we've got... some premade libraries duct taped together into a crappy browser that barely works. Of course when the value of this is compared to the cost, the response is that it's fine because it was never actually intended to be useful in the first place. Well we're actually a step ahead of you there.
The phrase "high on their own supply" describes all the people involved in this very well. I assure you we understand the goal of this project perfectly. It just wasn't a good, worthy, or even interesting goal. The immense amount of resources that went into this should have gone into something better. That's all there is to it.