systemd

Set up restic backups on Debian 13: SFTP or S3 repos, a sandboxed systemd timer, forget --prune retention, append-only rest-server and restore tests.

No space left on device but df shows free space? Debug exhausted inodes, deleted files held open by processes and a bloated systemd journal on Debian 13.

Sandbox systemd services on Debian 13: score units with systemd-analyze security, harden nginx via a systemd drop-in, then debug whatever breaks.