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Damn that was inspiring! Good motivation and appreciate the level of detail.

Can't speak to the legal requirements, but in terms of professional courtesy you should probably include the original authors, especially if it's a 1:1 rewrite in another lang. It feels equivalent to translating a book to a new lang - you wouldn't get sole copyright there?

Claude Code weighs in (and dodges giving a definitive answer).

as long as there is good test coverage!

colloquially just "best" but strictly speaking I think it might refer to a pareto frontier: en.wikipedia.org/wiki/Pareto_...

Have you got a read on which is “best” or are they all about the same?

Do you know if someone has attempted the "meta challenge" of building a repo that will write an implementation in your favourite language? Would be interesting to see how well the idea "use LLM as compiler of specs to super personalised implementation" works today

When I wrote about my JustHTML port from Python to JavaScript last month I chickened out and finished the post with some open questions - I've now made an attempt at providing my own answers to those questions here: simonwillison.net/2026/Jan/11/...

I’ve been making a tool to follow along w/these things. has a web UI as it draws its decision graph of observations goals options outcomes & actions in a DAG & helps you see its process & guide things along. Disclaimer: I made it over nights/weekends the past 2wks. Would be curious your 2 cents

Inspired by your experience, I made an experiment of porting a SOTA TTS model from Python to Rust: github.com/ayourtch/fis... - took 4 days on and off, with the final stage being 2hr opencode Opus 4.5, comparing the inference layer by layer, and periodically asking me if the audio sounded good :-)

TDD, the spec IS the code.

I wonder if you could run that on infinitemac.org

First time watching Knives Out? What did you think? 😊

Hi @halojinix, I'm a junior engineer, can I get Git access?

I really enjoyed it! It was a bit too long but it hit all the right notes for me otherwise

I wrote pybench github.com/lucianmarin/... with AI too. It's small compared to what you have done.

@simonwillison.net Absolutely fascinating stuff Simon. I had the exact same idea a few days ago, ironically when I encountered a different parsing library I wanted to port to Swift for @plinky.app). I very much appreciated the moral questions at the end too, since similar thoughts crossed my mind.