alt Hacker NewsThe 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...
Replies
Also selectors and taffy.
It's also using weirdly old versions of some dependencies (e.g. wgpu 0.17 from June 2023 when the latest is 28 released in Decemeber 2025)
> The JS engine used a custom JS VM being developed in vendor/ecma-rs as part of the browser, which is a copy of my personal JS parser project vendored to make it easier to commit to.
Honestly as soon as I saw browser in rust I assumed it had just reproduced the servo source code in part, or utilised its libraries.
[dead]
To be fair, even if "from scratch" means "download and build Chromium", that's still nontrivial to accomplish. And with how complicated a modern browser is, you can get into Ship of Theseus philosophy pretty fast.
I wouldn't particularly care what code the agents copied, the bigger indictment is the code doesn't work.
So really, they failed to meet the bar of "download and build Chromium" and there's no point to talk about the code at all.
Yeah, it's
- Servo's HTML parser
- Servo's CSS parser
- QuickJS for JS
- selectors for CSS selector matching
- resvg for SVG rendering
- egui, wgpu, and tiny-skia for rendering
- tungstenite for WebSocket support
And all of that has 3M of lines!