Four profiles, each tested to a systemd-analyze security score below 2.5.

Profile Score Notes
web-app.conf 1.8 Network egress restricted; JIT-compatible
worker.conf 1.4 No inbound sockets
network-daemon.conf 2.3 Retains CAP_NET_BIND_SERVICE
batch-isolated.conf 0.9 PrivateNetwork, no egress at all

Copy into /etc/systemd/system/<unit>.service.d/, then run systemctl daemon-reload && systemctl restart <unit>.