I tried it for a job interview, and it was awful - because of no static typing. I spent most of my time tracking down dumb type errors, compounded by various language footguns (I can't remember exactly, but I think for example making a typo on a field name in a for loop condition is treated as "condition false" and so the for loop just doesn't do anything, no error).

It seems like the Elixir/Erlang community is aware of this, as is Ruby, but it's a rather large hole they have to dig themselves out of and I didn't feel particularly safe using the tools today.

I've heard a lot of good things about the Erlang runtime and I did really like Elixir's pipe operator, so it was unfortunate.