How to Use Scope-Type Variables in Java

We're trying to sort of have a better story around scope-type variables. That's been a big thing that we've been working on. Just to have a slightly more principled story around them and where you can introduce them in patterns, something that most programmers won't notice. There was actually a proposal some years ago to try to separate that out but everyone decided, ah, this just isn't worth introducing a new extension. It's a bit silly. So do you have any advice for like a newcomer that wants to contribute to J.C. but has like very little knowledge?