This seems huge.

Does anyone know plans around how this will be implemented into Rails?

This is all new to me as well, but the project mentioned the Falcon web server(https://github.com/socketry/falcon).

The documentation for Falcon mentions using it with rails: https://socketry.github.io/falcon/guides/rails-integration/i...

I imagine something more "native" to rails will happen eventually though. But would need to be after this makes its way into core ruby(which has not happened yet apparently).