apenwarr/bup. A very interesting small tool that manages backups differentially - and that is based on the git data structures. In principle, one could consider it as an intelligent splitter for large files with minor changes in each version - for example, tar files from servers. For this purpose, an rsync-like algorithm is used to determine the differences and the result is stored in a git archive. The whole thing can also be combined with the previous git-annex and thus provide a space-saving backup solution.