Backup all the backups
In the !Freedombone project I learned early on that to run intependent internet services you really need to have a good backup system in place. Databases can get corrupted. Disks can fail. Or there can be bugs which just screw things up.On Freedombone you can do encrypted backups to external storage and also restore individual apps via the control panel. It's also possible to backup automatically to remote servers in what I call the web of backups. That system uses key splitting such that even in the worst scenario where your house burns down the data can still be recoverable.
Behind the scene the backup system is based on Obnam and libgfshare.