Comment by mjr00

6 hours ago

What people take issue with is the claim that agents built a web browser "from scratch" only to find by looking deeper that they were using Servo, WGPU, Taffy, winit, and other libraries which do most of the heavy lifting.

It's like claiming "my dog filed my taxes for me!" when in reality everything was filled out in TurboTax and your dog clicked the final submit button. Technically true, but clearly disingenuous.

I'm not saying an LLM using existing libraries is a bad thing--in fact I'd consider an LLM which didn't pull in a bunch of existing libraries for the prompt "build a web browser" to be behaving incorrectly--but the CEO is misrepresenting what happened here.

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mjr00

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square_usual  6 hours ago

Did you read the comment that started this thread? Let me repeat that, ICYMI:

> "So I agree this isn't just wiring up of dependencies, and neither is it copied from existing implementations: it's a uniquely bad design that could never support anything resembling a real-world web engine."

It didn't use Servo, and it wasn't just calling dependencies. It was terribly slow and stupid, but your comment is more of a mischaracterization than anything the Cursor people have said.

simonw  6 hours ago

I agree that "from scratch" is a misrepresentation.

But it was accompanied by a link to the GitHub repo, so you can hardly claim that they were deliberately hiding the truth.

  • tyre  5 hours ago

    Sorry, just to be clear, the defense that they pulled something out of their ass is that they linked to something that outed them? So they couldn't have actually have been overstating it?

    If anything, that proves the point that they weren't rigorous! They claimed a thing. The thing didn't accomplish what they said. I'm not saying that they hid it but that they misrepresented the thing that they built. My comment to you is that the interview didn't directly firmly pressure them on this.

    Generating a million lines of code in parallel isn't impressive. Burning a mountain of resources in parallel isn't noteworthy (see: the weekly post of someone with an out of control EC2 instance racking up $100k of charges.)

    It would have been remarkable if they'd built a browser from scratch, which they said they did, except they didn't. It was a 50 million token hackathon project that didn't work, dressed up as a groundbreaking example of their product.

    As feedback, I hope in the future you'll push back firmly on these types of claims when given the opportunity, even if it makes the interviewee uncomfy. Incredible claims require incredible evidence. They didn't have it.

    • simonw  5 hours ago

      My goal in the interview was to get to as accurate a version of what they actually built and how they built it as possible.

      I don't think directly accusing them of being misleading about what they had done would have supported that goal, so I didn't do it.

      Instead I made sure to dig into things like what QuickJS was doing in there and why it used Taffy as part of the conversation.

      2 replies →

  • Fervicus  6 hours ago

    How many non developers were going to look at that? They knew exactly what they were doing by saying that.

  • mjr00  6 hours ago

    > But it was accompanied by a link to the GitHub repo, so you can hardly claim that they were deliberately hiding the truth.

    Well, yes and no; we live in an era where people consume headlines, not articles, and certainly not links to Github repositories in articles. If VCs and other CEOs read the headline "Cursor Agents Autonomously Create Web Browser From Scratch" on LinkedIn, the project has served its purpose and it really doesn't matter if the code compiles or not.