@paul_d Take a look at Restic: https://restic.net , GitHub - restic/restic: Fast, secure, efficient backup program
It is written in Go and compiled versions are available for Windows, too. It is a commandline tool. If you need a kind of GUI and scheduling out of the box, you can use Duplicati (https://www.duplicati.com). But I like the secure deduplication and snapshoting approve (a little bit like Seafiles filesystem) of Restic more!
I’m using Restic on my server to backup/snapshot Nextcloud, MariaDB, Gitlab, website document roots and a minecraft server to Backblaze B2 and so far I’m pretty impressed by this piece of software. In some areas it is not completely matured yet, but I think the core features are quite solid and the developer team especially the creator is supportive and very active and I find the community itself really nice.