An almost perfect rsync over SSH backup script
Too complicated to even try to read.  Rsync is great but I've switched to Borg for backups.  Borg isn't perfect but it is a higher level approach to backups, as it were.  Hetzner recently dropped the price of their Storage Box backup product to about 2 euro per TB per month, and Borg works nicely with it.  Borg encrypts all the backup contents and conceals the metadata on the backup server, and yet you can (with the encryption passphrase) mount the backup archive as a read-only file system through FUSE and access it through normal file navigation.  It is impressive.