The value to me (other than OTP + friends) is not what Elixir gives you, but what it takes away. Not being able to monkey patch things and change mutable state is really freeing. You can do it if you're diligent, of course (I code Java with as many static methods and final, immutable fields as I can and what I know about Ruby, it has things like freeze), but it's hard to never reach for a tool "just this once" if you're in a time crunch.