> It runs well, so far so good, but I have the interactive interpreter. As soon as I shut down, the service disappears.
This is where 'screen' comes in handy. Screen is a threaded model: it assigns a single thread for each 'screen' used. It also has a built in command to detach from your screen session (CNTRL+a d). After detaching you can then close the terminal window and arc will still be running as a silent thread. To get back just launch screen with the option to re-attach ($ screen -x).
