I'm glad it's 1.0, but for me the most exciting thing is the tensor shape typing they mention in the blogpost. I've been looking for a good solution to this for ages, and the Pyrefly implementation seems to have everything I'd like - incl. static typing (unlike jaxtyping's runtime-only setup), and shape inference (so passing a 2,3 tensor through a 3,10 linear layer gives you a 2,10 output tensor).