If you're aching for typespecs in Elixir being useful, but are dissapointed with Dialyzer, I recommend checking out my library Hammox: https://github.com/msz/hammox. It's an improved version of Mox, the de-facto mocking library for Elixir, which you can use to automatically assert in tests that your mock calls, or any function calls, fit your typespecs.

I personally found that with rigorous enough usage, I don't even miss having actual static typing anymore ;)