I thought the same thing. Either he means that he learned the very finer parts of Rust on the job but knew it well to begin with. OR. He was really doing 40 hou

I thought the same thing. Either he means that he learned the very finer parts of Rust on the job but knew it well to begin with. OR. He was really doing 40 hours of work and 40 hours of Rust learning per week. Which is fine too, as he delivered.