RustCoach teaches Rust by making you write it. An AI coach (built on Claude) writes each lesson for you, remembers what you got wrong, and re-tests it before moving on. Every lesson ends with a real assignment: your code compiles and runs against cargo tests and clippy in a sandbox, then gets reviewed like a pull request. Stuck? You get hints and a line-by-line trace, never the answer. 16 chapters, spaced review cards. Free to start, $49 once, no subscription.