Python Type Checker Comparison: Typing Spec Conformance

When you write typed Python, you expect your type checker to follow the rules of the language. But how closely do today's type checkers actually follow the Python typing specification? In this post, we look at what typing spec conformance means, how different type checkers compare, and what the conformance numbers don't tell you.

https://pyrefly.org/blog/typing-conformance-comparison/