 
   def run([]) do
     header()
-    IO.puts("We're missing an AppSignal Push API key and cannot continue.")
-    IO.puts("Please supply one as an argument to this command.\n")
-    IO.puts("  mix appsignal.install push_api_key\n")
-    IO.puts("You can find your push_api_key on https://appsignal.com/accounts under 'Add app'")
-    IO.puts("Contact us at support@appsignal.com if you're stuck.")
+
+    """
+    We're missing an AppSignal Push API key and cannot continue.
+    Please supply one as an argument to this command.
+
+      mix appsignal.install push_api_key
+
+    You can find your push_api_key on https://appsignal.com/accounts under 'Add app'
+    Contact us at support@appsignal.com if you're stuck.
+    """
+    |> IO.puts()
   end
 
   def run([push_api_key]) do

  end

  defp header do
    IO.puts("AppSignal install")
    IO.puts(String.duplicate("=", 80))
    IO.puts("Website:       https://appsignal.com")
    IO.puts("Documentation: http://docs.appsignal.com")
    IO.puts("Support:       support@appsignal.com")
    IO.puts(String.duplicate("=", 80))
    IO.puts("\nWelcome to AppSignal!\n")
    IO.puts("This installer will guide you through setting up AppSignal in your application.")
    IO.puts("We will perform some checks on your system and ask how you like AppSignal to be ")
    IO.puts("configured.\n")
    IO.puts(String.duplicate("=", 80))
    IO.puts("")
  end

  defp validate_push_api_key do
    IO.write("Validating Push API key: ")

  end

  defp output_config_environment_variables(config) do
    """
    Configuring with environment variables.
    Please put the following variables in your environment to configure AppSignal.

      export APPSIGNAL_APP_NAME="#{config[:name]}"
      export APPSIGNAL_APP_ENV="prod"
      export APPSIGNAL_PUSH_API_KEY="#{config[:push_api_key]}"
    """
    |> IO.puts()
  end

  defp write_config_file(config) do
