catsby

$ ls
other_thing.exs
thing.exs

$ elixir thing.exs                                                                                                                    
calling other
other thing!
hooray!

rbishop

Generate a new Elixir project using mix and add cowboy and plug as dependencies in mix.exs:

  defp deps do
    [
      {:cowboy, "~> 1.0.0"},
      {:plug, "~> 0.8.1"}
    ]
  end

mudphone

defmodule Math do

  def add(x, y) do
    x + y
  end

  def add(x, y, z) do
    x + y + z
  end

likethesky

$ brew update && brew doctor          # Repeat, until you've done *all* the Dr. has ordered!
$ brew install postgresql             # You'll need postgres to do this... you may also need to 'initdb' as well. Google it.

$ brew install elixir
$ mix local.hex                       # Answer y to any Qs
$ createuser -d postgres              # create the default 'postgres' user that Chris McCord seems to like -- I don't create mine w/a pw...

# Use the latest Phoenix from here: http://www.phoenixframework.org/docs/installation -- currently this is 1.0.3
# ** Answer y to any Qs **
$ mix archive.install https://github.com/phoenixframework/phoenix/releases/download/v1.0.3/phoenix_new-1.0.3.ez