Can anyone recommend a backup strategy for iCloud? Specifically, my Macs' hard drives aren't big enough for any one computer to store everything locally, so some documents end up living only in iCloud which is clearly asking for trouble. My ideal solution would be to regularly mirror iCloud's contents on my NAS (which is big enough to store everything locally) but I've never seen anyone implement something like that.
I run this as a container in my nas (unraid).

https://github.com/boredazfcuk/docker-icloudpd

It’s been great for backing up for backing up photos and videos. Haven’t tried any other files though.