# bup/bup

Very efficient backup system based on the git packfile format, providing fast incremental saves and global deduplication (among and within files, including virtual machine images). Please post problems or patches to the mailing list for discussion (see the end of the README below).

Repository: https://github.com/bup/bup
Canonical: https://ross.abutalabs.com/products/bup
Homepage: https://bup.github.io/
Language: Python
License: NOASSERTION
License Family: other
Last push: 2026-08-22T20:11:42+00:00

## Health v2 (maintenance only)
Score: 77/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 35, longevity 100
- inputs: {"age_days": 5112, "days_push": 11, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 7341, forks 425 (observed 2026-08-28T04:09:58.343393+00:00)

## What it is
bup is a highly efficient open-source backup system built on the git packfile format. It provides fast incremental saves with global deduplication across and within files, making it well suited for backing up huge files like VM disk images.

## Use cases
- back up large virtual machine disk images incrementally
- deduplicate backup data across machines and backup sets
- restore any incremental backup as if it were a full backup
- mount a backup repository as a FUSE filesystem
- back up directly to a remote server over ssh
- recover corrupted backups with par2 redundancy

## When to choose
- you need space-efficient incremental backups of huge files like VM images or databases
- you want global deduplication without managing full/incremental chains
- you prefer storing data in an accessible format like git packfiles
- you want to back up to a remote server over ssh with minimal temp space

## When to avoid
- you need a polished, widely tested tool with a mature GUI
- you want simple archive-style backups like tar
- you need built-in encryption of backup data
- you require official Windows support or a turnkey backup solution

## Facets
- artifact type: cli-tool
- maturity: maintenance
- function: backup, compression, file-system, cli
- domain: files, developer-tools, self-hosted
- platform: python, cli
- tags: deduplication, incremental-backup, git-packfile, fuse, rsync-rolling-checksum, linux, macos

## Member repositories
- bup/bup (main) score 77

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:58.343393+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:38:27.761101+00:00, confidence not recorded.
  - readme: https://github.com/bup/bup (fetched 2026-08-28T04:09:58.343393+00:00, sha 71a980aac6da)
  - homepage: https://bup.github.io/ (fetched 2026-08-29T08:33:55.854028+00:00, sha ec5f86226d28)
- Data as of 2026-08-30T08:39:29.467469+00:00.