I’m experimenting with Hexagonal / Clean Architecture in Elixir. The classic Behaviour + Impl split works great for mocking and isolating IO—here’s a trimmed-down example from our SFTP adapter:

elixir

# Port (Behaviour)
defmodule Core.SFTP.Port do
  @callback connect(map()) :: {:ok, term()} | {:error, term()}
  @callback write(Path.t(), iodata()) :: :ok | {:error, term()}
  @callback disconnect(term()) :: :ok | {:error, term()}
end

# Adapter (Impl)
defmodule Core.SFTP.Live do
  @behaviour Core.SFTP.Port

  @impl true
  def connect(conf),         do: SFTPClient.connect(conf)
  @impl true
  def write(path, data),      do: SFTPClient.write_file(path, data)
  @impl true
  def disconnect(conn),       do: SFTPClient.disconnect(conn)
end

I wanted to know what are architectural patterns in elixir , apart from behaviour and impl pattern