Backward compatibility doesn't mean that you write code with the latest features, then go back to a version that's a year old than expect it to work. No languag

Backward compatibility doesn't mean that you write code with the latest features, then go back to a version that's a year old than expect it to work. No language or software does that. The promise is that if you have code you didn't touch for a year, you can update Rust, and it will still compile. You got it backwards.