rsass
Sass reimplemented in rust with nom (very early stage). The "r" in the name might stand for the Rust programming language, or for my name Rasmus.
The build contains a small but growing number of tests from https://github.com/sass/sass-spec . A default run of sass-spec found 420 of 3286 tests running (or 449 of 6041 when claiming to be libsass). So this project is really not done yet.
If you want a working rust library for sass, you will probably be better of with sass-rs which is a rust wrapper around libsass, or possibly sassers which is another early stage pure rust implementation. That said, this implementation has reached a version where I find it usable for my personal projects, and the number of working tests are improving.