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The latest entrant in the coding-agent-constructed web browsers is here, this one by @emsh.cat, and it's REALLY impressive - 3 days of development, 20,000 lines of Rust, no Cargo dependencies and it renders HTML+CSS extremely well simonwillison.net/2026/Jan/27/...

simonwillison.netOne Human + One Agent = One Browser From Scratchembedding-shapes was so infuriated by the hype around Cursor's FastRender browser project - thousands of parallel agents producing ~1.6 million lines of Rust - that they were inspired to take …

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The one I did literally won't be more than a proof of concept and experiment :) Building an actual production-worthy browser from scratch would probably be a much larger project. I think. Maybe someone should investigate? 👀

As long as people stop lying about what they've done and verify their claims before they make them public, we're all indeed just having fun ^_^

I'd love it if someone familiar with Servo internals did take a closer look! Wouldn't surprise me. During our sessions, when I was watching (maybe 20% of the time) I didn't see it search for anything Servo, nor browse any Servo code. But might have slipped in, not 100% sure.

Agree :) What people haven't considered yet, is "Good Taste" will become more important. More on that here: emsh.cat/good-taste/ TLDR: > I don't want a machine that replaces my taste, I want tools that help me use my taste better

This is pretty impressive! It's amazing what agents can do now. I wonder what experience the software engineer had when setting up this project and managing the agents? Were they familiar with browser development? Experienced in other areas? A pure vibe coder?

I'm a software engineer with ~1.5 decades of experience, mostly web development but been moving across stacks the entire time. Generally consider myself a generalist :) Through the years been focusing a lot on testing, infrastructure and architecture/design, guess that's helpful now.

> managing the agents? Just one agent (codex) + me, side by side in the terminal, me taking notes on the right, codex doing it's thing on the left :)