How did this guy test systemd exactly?

Raw sockets. + there are various socket options I need to have set on connectionless sockets (e.g. multicast memberships; various meta-data retrieval options which might need to be set before packet is put into the socket). Routing stuff tends to use a variety of far-out options (and new ones come along not too infrequently - e.g. GTSM). ;)

Further, if I can specify these things in code, rather than in a config file, then I can share that code between the "setup socket(s) for systemd" binary and the main body of code. Which would help reduce redundancy and hence mistakes.

I'd like to say "I'll send you a patch", but my TODO list is several kms long at this stage. :(