kopia

Kopia is a free, open-source backup software that creates encrypted, deduplicated backups stored in a repository. A repository can reside on a local disk, a network share, or cloud object storage, enabling off-site protection and scalable storage.

Interfaces include a command-line interface and a web-based graphical user interface. Kopia runs on Windows, macOS, and Linux, and supports automation through scripts and scheduled tasks.

Core capabilities include encryption at rest, content-addressable deduplication to minimize storage usage, and time-stamped snapshots that capture the state of selected data at backup time. It supports incremental backups and retention policies to manage older snapshots and ensure predictable storage use. Restoration can be performed for individual files, directories, or entire snapshots.

Storage backends are pluggable and cover local filesystems as well as several cloud and object stores, including S3-compatible services, Google Cloud Storage, Microsoft Azure, Backblaze B2, Wasabi, and other providers.

Development and licensing: Kopia is developed by an open-source community and maintained on its official repository. The project is written in Go, and the software is released under an open-source license.