[s6ro]

Elixir is functional and immutable first, (and structs) - that alleviates somewhat the pain of not having a strong type system. I really like the architecture of OTP, but I still find myself using Elixir in anger.

Especially, if I'm trying to bring and old(er) codebase (Elixir 1.9) up to the newest release... and upgrading packages, checking if things are likely to brake etc.

I constantly find myself realising that I cannot trust the compiler, which means more defensive coding, more tests, more time spent...

As an example, upgraded postgrex. The return tuple of one its functions had changed from 2 elements to 3 elements. Did the compiler caught it? No. Had I had dialyzer type spec-s on my private function, I would at least gotten a warning. Thus, morale of the story: always type spec even your private functions , especially if they use 3rd party code.