> I also miss the way that JavaScript encouraged people to define very simple function signatures (e.g. strings, numbers, plain objects/clones as arguments and

> I also miss the way that JavaScript encouraged people to define very simple function signatures (e.g. strings, numbers, plain objects/clones as arguments and return values). I wish this were true, and maybe it was in some cases, but not broadly. Many "types" used in JavaScript libraries are horribly complex. For example, the type signature of jQuery's `$` function, or moment.js's main function, or `server.listen` in Node.js, etc. In fact I think the opposite argument from yours could be made with a straight face: not having to declare types encourages more complexity. I don't really agree with that either, though; in my experience this is more a matter of developer discipline and API design skills. One thing I'm certain of is that if libraries are going to have complex types, I'd much rather have them be explicit and machine-verifiable vs hidden/implicit/hope-the-developer-wrote-a-good-docstring.