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[return to "Cursor's latest “browser experiment” implied success without evidence"]
1. nindal+BA[view] [source] 2026-01-16 17:25:56
>>embedd+(OP)
The CEO said

> It's 3M+ lines of code across thousands of files. The rendering engine is from-scratch in Rust with HTML parsing, CSS cascade, layout, text shaping, paint, and a custom JS VM.

"From scratch" sounds very impressive. "custom JS VM" is as well. So let's take a look at the dependencies [1], where we find

- html5ever

- cssparser

- rquickjs

That's just servo [2], a Rust based browser initially built by Mozilla (and now maintained by Igalia [3]) but with extra steps. So this supposed "from scratch" browser is just calling out to code written by humans. And after all that it doesn't even compile! It's just plain slop.

[1] - https://github.com/wilsonzlin/fastrender/blob/main/Cargo.tom...

[2] - https://github.com/servo/servo

[3] - https://blogs.igalia.com/mrego/servo-2025-stats/

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2. wilson+Bu2[view] [source] 2026-01-17 08:46:43
>>nindal+BA
Thanks for the feedback. I've addressed similar feedback at [0] and provided some more context at [1].

I do want to briefly note that the JS VM is custom and not QuickJS. It also implemented subsystems like the DOM, CSS cascade, inline/block/table layouts, paint systems, text pipeline, and chrome, and I'd push back against the assertion that it merely calls out to external code. I addressed these points in more detail at [0].

[0] >>46650998 [1] >>46655608

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3. nindal+pD2[view] [source] 2026-01-17 10:29:02
>>wilson+Bu2
> I do want to briefly note that the JS VM is custom and not QuickJS

It's hard to verify because your project didn't actually compile. But now that you've fixed the compilation manually, can you demonstrate the javascript actually executing? Some of the people who got the slop compiling claimed credibly that it isn't executing any JavaScript.

You merely have to compile your code, run the binary and open this page - http://acid3.acidtests.org. Feel free to post a video of yourself doing this. Try to avoid the embellishment that has characterised this effort so far.

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4. Snuggl+3G2[view] [source] 2026-01-17 11:07:29
>>nindal+pD2
This is from the "official" build - https://imgur.com/fqGLjSA

The "in progress" build has a slightly different rendering but the same result

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