docker-compose.yml

services:
  borgmatic:
    image: modem7/borgmatic-docker
    container_name: Borgmatic
    # Set a fixed hostname so borgmatic's {hostname} archive name format stays
    # consistent across container rebuilds. Without this, each rebuild gets a
    # new random hostname, causing prune and compact to miss older archives.
    hostname: borgmatic
    volumes:
      - ${VOLUME_SOURCE}:/mnt/source:ro                        # backup source
      - ${VOLUME_TARGET}:/mnt/borg-repository                  # backup target
      - ${VOLUME_ETC_BORGMATIC}:/etc/borgmatic.d/              # borgmatic config file(s) + crontab.txt
      - ${VOLUME_BORG_CONFIG}:/root/.config/borg               # config and keyfiles
      - ${VOLUME_SSH}:/root/.ssh                               # ssh key for remote repositories
      - ${VOLUME_BORG_CACHE}:/root/.cache/borg                 # checksums used for deduplication
      - ${VOLUME_BORGMATIC_STATE}:/root/.local/state/borgmatic  # borgmatic state (periodic check tracking)
      # Optional: mount hook scripts from a dedicated directory
      # - ./borgscripts:/borgscripts:ro
      # Optional: run custom init scripts at container startup
      # - ./custom-cont-init.d:/custom-cont-init.d:ro
      # Optional: mount Docker socket to stop/start containers during backup
      # - /var/run/docker.sock:/var/run/docker.sock
    environment:
      - TZ=${TZ}
      - BORG_PASSPHRASE=${BORG_PASSPHRASE}
      # Pass through env vars used in borgmatic config files (${VAR} expansion)
      # - BORG_SOURCE_1=${BORG_SOURCE_1}
      # - BORG_REPO=${BORG_REPO}
      # - BORG_HEALTHCHECK_URL=${BORG_HEALTHCHECK_URL}
      # Install Docker CLI for container stop/start hooks
      # - DOCKERCLI=true
      # Custom cron schedule and command (overrides crontab.txt and default)
      # - CRON=${BORG_CRON}
      # - CRON_COMMAND=${BORG_CRON_COMMAND}
      # Additional cron jobs (multi-line YAML block scalar)
      # - EXTRA_CRON=|-
      #     @daily borgmatic-start check -v 1 2>&1
      #     0 7 1 * * borgmatic-start compact 2>&1
      # Additional Alpine packages to install at startup
      # - EXTRA_PKGS=rclone jq
    logging:
      driver: local
      options:
        max-size: 10m
        max-file: "3"
    restart: unless-stopped
    stop_grace_period: 10m  # allow in-progress backups to finish cleanly on docker stop