That looks interesting. Unfortunately it looks like it hasn't been updated in a while? Is that because it's complete or a lack of interest?

For example, the approach mentioned at the bottom of the README of integrating via nlvm (https://github.com/arnetheduck/nlvm) sounded great but appears to be unpursued.

that looks interesting, thanks! Did you try it if it delivers on promises? There was not any new commit since 2020 so not sure if the project is stale by now.

I do not use Rust, so sadly I have not.

As a 2-step approach, you could also probably use https://github.com/mozilla/cbindgen and then Nim's native C FFI.