I really like the copyleft idea, however, I think you did nothing wrong, IMHO, because if large corps like an idea, they will rather reimplement it rather than even bothering with ways to conform to AGPL or buy an alternative licence. Particular in the age of AI, all source available code has become pretty much public domain (value is still in maintenance, etc). License have mostly become a compliance/ideology game that alienates most people. However, changing the license on the main repo, with only a minor version bump, would be a nice asshole move to get their attention past HR (won't make a difference, but if you have nothing to lose).

Nah, forget this attitude of yours. You created something that a behemoth like Anthropic uses and literally noone thought about compensating you. Kick the ladder out of them, and go hard on their balls.

> but it is common for crates to be released under MIT

Something that isn't brought up enough in the "rewrite everything in Rust" discussions is that the API guidelines explicitly recommend MIT/Apache to "maximize compatibility" (i.e., corporate friendliness, or developer and user exploitation): https://rust-lang.github.io/api-guidelines/necessities.html#...

Your project has been around for a while, but it's crazy to me that anyone still open sources anything under MIT (or similar) in the era of LLMs. Are they that confident in their job security? Are they already independently wealthy? Frankly, even a proper copyleft license is likely to just be ignored, or the code laundered through an LLM-assisted rewrite, by these companies. I prefer to just keep anything I can't sell all to myself rather than release it, at this point.