Better to use a paste bin and ask specific questions rather than just please choose l critique this code.

I don’t like the current landscape of python type checkers.

I figure that Python itself is at the bottom of this. It simply wasn’t designed for static types. Mypy is still of some use but if you want a statically typed language, trying to graft a type system onto a unityped language hasn’t worked out well as far as I know. See also: the Erlang dialyzer, Typed Racket, and whatever that Clojure extension is called. Even Scala has its problems because the JVM has its own type system that isn’t that great a fit for Scala.

Also, why Rust as the implementation language? Just for speed? It seems a shame to not use Python/PyPy.