Yeah Erlang is slow as hell for number crunching but then when you see this:

(Handbook of Neuroevolution Through Erlang) https://www.springer.com/us/book/9781461444626

You're like huh. There's people that's doing it. I don't know how but yeah. I can't even crunch prime number on it without giving up cause of how slow it is.. I guess there's more to it.