Yes, there's one reason not to use Elixir that I know of: [Edit: It appears I might be wrong on this.]
It doesn't fully cover the erlang syntax. There are a few things you can do in erlang that you can't in elixir.
As I understand it, this will be resolved relatively soon, in an upcoming release, possibly only in a matter of months.
Elixir and erlang can be mixed pretty easily, so there's no harm in trying a module in elixir just to see how you like it. Underneath, it's "erlang all the way down", so you're unlikely to run into problems.
I don't know. I'm new to the language, and after doing the "crash course for erlang developers" and reading the release notes about a month ago, I believe I read that there wasn't full coverage, and that it was expected in 8.0 (or maybe 7.4?)
You probably have forgotten more than I know about this language, so I'm just going to assume I'm mistaken (or was reading something out of date.)
It doesn't fully cover the erlang syntax. There are a few things you can do in erlang that you can't in elixir.
As I understand it, this will be resolved relatively soon, in an upcoming release, possibly only in a matter of months.
Elixir and erlang can be mixed pretty easily, so there's no harm in trying a module in elixir just to see how you like it. Underneath, it's "erlang all the way down", so you're unlikely to run into problems.