A bulletin board system that enables radio amateurs to read and store messages at your station. It generally adopts conventions common to other popular packet BBS systems. Send and receive messages by callsign, send private messages, plugin architecture.
Doesn't actually have any networking code, it relies upon external software (the docs namecheck ax25d, but possibly any other utility which takes its input on stdin and prints to stdout (like go-sendxmpp?) might work).