It sounds like the actual async features come from Revolt so I’m not 100% sure where Rust fits in. Because the rust lib used is async as well, they’re compatible?
php-tokio's integrates the https://revolt.run event loop with the https://tokio.rs event loop; async functionality is provided by the two event loops, in combination with PHP fibers through revolt's suspension API (I could've directly used the PHP Fiber API to provide coroutine suspension, but it was a tad easier with revolt's suspension API (https://revolt.run/fibers), since it also handles the base case of suspension in the main fiber).
Yes, I'm planning to support my fork of ext-php-rs, given that it will be heavily used by our mongodb driver.
I've actually sent an email to David Cole, asking him to make a maintainer of the original repo, but he hasn't replied yet, feel free to send your MRs to our fork in the meantime!