zlacker

>>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/

>>nindal+BA
Is it using Servo's layout code or did Cursor write its own layout? That's one of the hardest parts.

>>wmf+Oo1
It seemingly did but after I saw it define a VerticalAlign twice in different files[1][2][3] I concluded that it's probably not coherent enough to waste time on checking the correctness.

Would be interesting if someone who has managed to run it tries it on some actually complicated text layout edge cases (like RTL breaking that splits a ligature necessitating re-shaping, also add some right-padding in there to spice things up).

[1] https://github.com/wilsonzlin/fastrender/blob/main/src/layou...

[2] https://github.com/wilsonzlin/fastrender/blob/main/src/layou...

[3] Neither being the right place for defining a struct that should go into computed style imo.