sysutils/kopia: New port: Fast and secure open-source backup/restore tool

Kopia is a fast and secure open-source backup/restore tool that allows
you to create encrypted snapshots of your data and save the snapshots
to remote or cloud storage of your choice, to network-attached storage
or server, or locally on your machine. Kopia does not 'image' your
whole machine. Rather, Kopia allows you to backup/restore any and all
files/directories that you deem are important or critical.

WWW: https://kopia.io/