[bglusman]

I'll briefly weigh in with others that you don't need to know Erlang, at least not Erlang syntax, to be effective in Elixir, and the semantics are identical. I think it's useful at some point to learn that all Elixir modules are just Erlang atoms, and to learn about OTP and that using anything built into Erlang is as simple as calling a function on an Atom instead of on an Elixir module. OTP is awesome, and so is Erlang, but I've been doing Elixir professionally for almost 3 years now and I've still never written a line of Erlang (though I did Prolog in college, on which its syntax is based, and I can generally manage to read most code in Erlang, but I've not found the need to often). Even Erlang libraries can be used from Elixir without any special interop, as long as they're published on hex.pm via rebar3. You just add them as a normal dependency in your mix.exs file, and it just works.