The Rust 2018 (1.31.0) prerelease is ready for testing. It’s scheduled to be released on Thursday the 6th. Release notes can be found here: https://github.com/rust-lang/rust/blob/stable/RELEASES.md.
You can try it out locally with:
RUSTUP_DIST_SERVER=https://dev-static.rust-lang.org rustup update stable
The index is https://dev-static.rust-lang.org/dist/2018-12-03/index.html.
This is following on the heels on our previous announcement for testing, and we’re entering the final stages now!