       0
   """
   def pop() do
-    GenServer.call(__MODULE__, :pop)
+    GenServer.call({:global, __MODULE__}, :pop)
   end
 
   @doc ~S"""

  Starts the server
  """
  def start_link() do
    GenServer.start_link(__MODULE__, [], name: __MODULE__)
  end

  @doc """
  Stops the server
  """
  def stop() do
    GenServer.stop(__MODULE__)
  end

  @doc ~S"""

      %Swoosh.Email{from: {"", "tony.stark@example.com"}, headers: %{"Message-ID": "a1b2c3"}, [...]}
  """
  def push(email) do
    GenServer.call({:global, __MODULE__}, {:push, email})
  end

  @doc ~S"""
