I was quite busy the past couple of days, but I finally managed to finish my mail-server migration.
And since I decided to also upgrade my old backup solution from the ancient times, I also wrote a guide for my new borgmatic based solution, which I now want to share with you guys.
I hope it helps some of you with your server backups.
On the off chance anyone uses BorgBase for off-site backups, I would like to shamelessly plug a Prometheus exporter I wrote for monitoring your account. It exports name, available/total space and last modified time for all repos in your account.