It is getting better but right now the few things I can recommend the most are:

• learn what an "OTP release" actually is and what it means. This alone will save you days of your life.

• do rolling restarts, doing live upgrades is difficult and not necessary for the vast majority of applications.

• read the prod.exs config, there's a commented out setting you'll need to enable. I forget the name of it, but it's on my github "tehprofessor" with the repo "flying with Phoenix" (its probably outdated in many ways but that setting is essential).

• remember the application is compiled and then run, so you really won't get any runtime configuration (likes Rails' environments).

• Docker can alleviate build pain a bit, as it stabilizes your environment-- I don't use it myself but it makes building a bit more pleasant from what others have told me.

• you'll very likely need to include all the applications, including ones listed in your dependencies (it's a pain in the ass), in your mix.exs applications list if you're using exrm.

... it's been a couple months as I've been on a coding hiatus for health reasons (and a broken arm) but I believe most of the above should still be very true.

That said and even with all the bitching I've had about it, I still love Elixir and Erlang. Though I've been moving more to pure Erlang as time goes on (FWIW).

Edit: clarity and note about loving me some elixir/erlang.