Hi HN, inspired by the Cursor team's attempt to use agents to vibe code a browser, I decided to try something a bit easier but still challenging enough to push the limits of current coding agents.

The result is a Python 3.14 targeting python interpreter written in Rust entirely by a single coding agent (Codex) in 30 days.

While the main focus is a native interpreter (macOS and linux atm) there is also a limited-functionality WASM version that you can try immediately on the website!

This was purely a fun project and I certainly had a lot of fun. My main role was playing pretend technical program manager and trying to prevent the agent from derailing (which it did very regularly). But anyway, 30 days, 342k lines of code, and nearly 2000 commits later, I have something that works.

I thought I'd be done in 3-5 days, then 2 weeks, then 3, before it was ready after 30 days. Feel like I've learned a lot more about these strange, impressive, and frustrating creatures that are agentic coding models as well.

Still a long way to go, and I will also be adding some performance benchmarks and test results in the coming days, but there it is.