ABR can now bridge to IRC, because of course.
It can also bridge Discord to Discord.
Bridging works transitively because I have a fairly elegant (if I do say so myself) way of handling it:
links are internally point-to-point, and when something is sent in a channel with links configured the bot traverses the graph of links to work out where to send to.
It is planned to expose a private websocket API to synchronize with other servers providing virtual channels.
This system is now used for telephone calls.
There may be issues in certain situations due to the lack of (meaningful) transaction support in aiosqlite.
The telephone command has been extended with (un)link commands, currently only for me as they can link anywhere.