Elixir does make you think hard about the global state you keep. It's an "eat your vegetables" decision, and I've acquired the taste. Keeps me out of trouble when designing things. Contrast this to Ruby, where class variables and globals are all over the place and thread safety is a pipe dream. [EDIT: it's not that Ruby-the-language forces this worldview, but Ruby-the-community adopted it and most Gems show the effects of that.]

As far as ivars, you'll have to work hard to emulate that. There are no classes or instances. Probably you want to just use a map or a struct to represent an instance and its state.