Simple Elixir Server as a Script

simple-elixir-server.exs

Mix.install([{:plug_cowboy, "~> 2.0"}])

defmodule Server do
  use Plug.Router
  plug(:match)
  plug(:dispatch)

  match _ do
    send_resp(conn, 200, "Hello World!")
  end
end

if System.argv() == ~w[server] do
  Plug.Cowboy.http(Server, [], port: 4000)
  System.no_halt(true)
end

# To install dependencies, just run: elixir app.exs
# To start server, run: elixir app.exs server