How To Do A For Loop In Elixir (using only recursion)

I’m Johnny Come lately on this subject but from what I’ve been told by the pro’s you’re not a programmer or at least you cannot get hired as one until you actually understand what’s going on under the hood. Sure Enum.each, Enum.map, etc are already implemented for us but most books I’ve read teach you how recursion works. I would assume that once Elixir becomes more mainstream programmers will be asked to implement recursive functions in interviews.