         {:found, result.value}
       end
     end
-  end
-
-  defp set(key, value, expires_in) do
-    GenServer.call(__MODULE__, {:set, key, value, expires_in})
-  end
-
-  def now do
-    :os.system_time(:millisecond)
-  end
-
-  ## Server Callbacks
-
-  def handle_call({:get, key}, _from, state) do
-    {:reply, Map.fetch(state, key), state}
+    {:reply, value, state}
   end
 
   def handle_call({:set, key, value, expires_in}, _from, state) do

  end

  defp get(key) do
    case GenServer.call(__MODULE__, {:get, key}) do
      :error -> {:not_found}
      {:ok, result} -> if now() >= result.expires_at do
        {:not_found}

                    %Entry{value: value, expires_at: now() + expires_in})
    {:reply, value, state}
  end

  defp now do
    :os.system_time(:second)
  end
end
