I was also pretty excited when I heard that they were baking autodiff into the language but unfortunately Swift has very little traction outside of mobile devel

I was also pretty excited when I heard that they were baking autodiff into the language but unfortunately Swift has very little traction outside of mobile development, which makes it a hard sell. I think a compiled subset of python is the best way to make that happen. All of the JITs (Numba, PyTorch, Jax, etc) already handle a decent portion of the language, so it should be doable.