I've been building Toast for awhile now. It's part of the new class of "JS tools, built in Rust". A Jamstack metaframework meant for digital gardens and the like. As a result I've been looking into incremental computation in Rust. Here's what I've found.
Basically the main option. Other libs on crates.io don't seem as polished or grounded in research.
Salsa is the lib referenced in the Rust compiler talk above. There are videos. Salsa is inspired by Adapton, Glimmer, and Rustc, but is listed as experimental.
salsa incremental recompilation
Not really related, but kinda useful for a very naive basic implementation.