As I understand it, Polonius is still intended to be the next version of the borrow checker. The repostory is here: https://github.com/rust-lang/polonius https

As I understand it, Polonius is still intended to be the next version of the borrow checker. The repostory is here: https://github.com/rust-lang/polonius https://github.com/rust-lang/polonius There doesn't seem to have been any meaningful development for well over a year. There is some very recent discussion on Zulip which makes it look like there are at least two or three people interested in actively working on it. https://rust-lang.zulipchat.com/#narrow/stream/186049-t-compiler.2Fwg-polonius/topic/polonius.20roadmap https://rust-lang.zulipchat.com/#narrow/stream/186049-t-comp...