- Backup/restore UFW configuration alongside iptables rules
- Backup sysctl.conf before any modifications (preserves original)
- Auto-backup before every add, delete, flush operation
- Rollback partially applied rules on iptables errors
- Save and restore UFW DEFAULT_FORWARD_POLICY on flush/delete
- Rotate backups (max 20) and logs (max 1 MB) automatically
- Lock file to prevent concurrent script execution
- Port conflict detection warns when port is already in use
- Support 'both' protocol (TCP+UDP simultaneously)
- Cross-distro package manager detection (apt, dnf, yum, pacman)
- Strict IPv6 validation via python3/perl with safe fallback
- Replace deprecated -m state with -m conntrack --ctstate
- Trap EXIT/INT/TERM for clean shutdown
- Add 'update' command to self-update from repository
- Add 'uninstall' command with full cleanup and config restoration
- Persist rules cross-distro (netfilter-persistent, iptables-services, manual)
- Extract _apply_rule_core to eliminate rule-application duplication
- Show UFW and backup count in status, mark UFW backups in restore list
arblark