True, but the key word is "can". I could write a proof that my dynamically typed programs are correct or that my functions do not index out of bounds, but I don

True, but the key word is "can". I could write a proof that my dynamically typed programs are correct or that my functions do not index out of bounds, but I don't. Nor has any programmer I've ever worked with. Nor has any open source project I've ever seen provide such proofs. People do not write these imaginary proofs, because it would be a waste of time.