Writing a Lisp "in a week" (that would be putting most of your time into the project) is a classic thing to do, and while it indeed isn't exactly system program

Writing a Lisp "in a week" (that would be putting most of your time into the project) is a classic thing to do, and while it indeed isn't exactly system programming, if you keep it simple (e.g. maybe limit it to atoms, lists and fixnums), but include precise GC, you'll learn a lot of things you need. Hmmm, I've been wanting to learn Rust, but I always need a project to learn a language, and I haven't written a Lisp "in a week" yet ^_^. Yeah, thanks for the idea.