Consider using mypyc

[blink1073]

We might be able to use mypyc to offer accelerated versions of the package for specific architectures.

[bollwyvl]

Yep, as long as there's still a -py3-none-any.whl (as on black), it shouldn't be super disruptive for downstreams. All the same, such a change might warrant a broad downstream canary testing before pulling the trigger... maybe a major version bump.

Of note, though, and maybe a bit late: it may be worth harmonizing some of the choices with annotated-types, now used by pydantic, etc.