Still a while to go. We've got some ideas, but nothing concrete yet, and it's hard to do in a backwards compatible form. And even if it stabilizes, there's no guarantee that things like clippy will be able to use it since clippy relies on a _lot_ of internals.
If you want to use a plugin like clippy, I'd suggest you make it an optional dependency (see the README) and do `cargo build --features=clippy` on nightly on your CI.
Related, at what point will "use a stable build, not a nightly" be a good practice for libraries? Actually, do people mainly use nightlies or releases for development? (Of libraries and apps, not the toolchain itself, obviously.)
