At We-Camp, the first day is a Code Retreat. This year, the "problem" was blackjack, rather than the usual Conway's Game of Life.
Paige Bolduc and Dave Aronson paired on the next-to-last round. That round's "twist" was to code in a "functional" style. (Most were using a more object-oriented style, mostly because this event was essentially a substitute for Ruby DCamp which wasn't happening in 2017 due to organizer personal reasons.) As we were both interested in (albeit somewhat newish to) Elixir, we decided to use that instead of Ruby.
We cheated, sort of. :-) At the end of a round of Code Retreat, you're supposed to delete your code. But we decided to keep plugging away at it. Since it looked like it could be fun, and there was way more to be done than we could do during We-Camp, Paige created this GitHub repo. (And so that Dave could submit a pull request, the last one he needed for a Hacktoberfest shirt.)
If others wish to submit PRs, I suppose we would be okay with that, but this is mainly an exercise for us to sharpen our Elixir-fu. So, a contribution more in line with what we're after would be critique. Please be gentle; remember that we did most of this with no Internet access nor much beyond the very basic Elixir tooling. :-)