This is great, thanks!

One of my favorite ways to learn a new language or framework is via "koans"[1], which this reminds me of. It's a gentle ramp up from basic to advanced features, and the TDD-like workflow of seeing a test fail, understanding why, and fixing it, is really conducive to learning, while giving you that dopamine jolt from "a-ha!".

[1]: https://github.com/ahmdrefat/awesome-koans/blob/master/koans...

sounds like a great way to learn a language "on your own". unfortunately, Rust is missing. can anyone propose a link?

Isn't that basically Rustlings?