Borg

A deduplicating backup program that stores data as content-defined chunks, so identical blocks are kept only once across files, machines and versions, with optional compression and authenticated encryption. Archives can be mounted as a regular filesystem for browsing, and the serve mode exposes a repository over SSH with path restrictions and an append-only mode that protects existing backups.

It is a common choice on Linux, macOS and BSD systems where daily backups need to stay small and fast, including virtual machine images and home directories on a NAS.

Running Borg yourself means your backup data stays on storage you own, there is no subscription to renew or per-host fee, and pruning and verification are scripts you control and can rehearse.