Level 1. Improved naming

chess.ex

defmodule Chess do
  alias Chess.{Board, Player, Move, Interaction}

  def play() do
    play(Board.init(), Player.first_turn(), 0)
  end

  def play(board, player, turn) do
    move = Interaction.read_move(player)

    case Move.execute(move, board, player) do
      {:ok, new_board} ->
        if Board.checkmate?(new_board) do
          Interaction.victory(player, turn)
        else
          play(board, Player.next(player), turn + 1)
        end

      {:error, illegal_move} ->
        Interaction.illegal_move(player, illegal_move)
        play(board, player, turn)
    end
  end
end