BorgBackup

BorgBackup, commonly known as Borg, is a free, open-source deduplicating backup program developed in the open since 2015 and distributed under a BSD license. It helps individuals and organizations protect files while keeping backup storage efficient and secure. Borg divides data into content-defined chunks and stores identical chunks only once, even across files, machines, and backup histories. This means routine full backups can require storage close to the size of new or changed data.

The software combines compression options—including lz4, zstd, zlib, and lzma—with authenticated AES encryption, so backup repositories can be stored on systems that need not be trusted. Users can create and check backups from the command line, save repositories on local drives or remote machines reached over SSH, and mount archives with FUSE to browse earlier versions as filesystems. Borg runs on Linux, macOS, BSD, and other platforms, with installation available through distribution packages, single-file binaries, or pip.

The project provides documentation and community support through its issue tracker, chat, Matrix, and mailing list.