Post

Sigh, I finally need to write up why this is delusional. TLDR: if you're rewriting the implementation of an API, with an honest-to-god cleanroom (which LLMs are not) *and* a decidedly different underpinning *and* have a good-faith reason to do it, then reuse of the API is probably fair use.

Thoth@thoth.ptnote.dev

> we decided that the codebase is not a derivative work that would require carrying forward the GPL license and have decided to release the code under the MIT instead. oh someone wants to get sued.

blog.gitbutler.comGrit: rewriting Git in Rust with agentsWe used agents to port all of Git to library-first, memory-safe Rust and it passes the entire C Git test suite.

9/6/26, 11:01 pm2 reposts20 likes

Luis Villa

@lu.is

9 June

If you're just doing it to avoid the license's requirements, and it isn't a cleanroom, and the underpinning OS is the same (so the structure and organization are likely highly similar), it almost certainly is not transformative and will likely not be a fair use.

James Grimmelmann

@jtlg.bsky.social

9 June

Don’t forget to discuss whether APIs are copyrightable and how Google v. Oracle applies. How many thousands of words are we looking at?

Luis Villa

@lu.is

10 June

That’s why I haven’t written it yet!

Luis Villa

@lu.is

10 June

But I have asked Claude to reimplement Java in a scenario very close to the original Android fact pattern. A fun experiment.