Systemd programming part 2: activation and language issues

Hmm? Could you be more specific? Sometimes dependencies are configuration-related. For example, I run nginx in front of any service which uses a web interface. How would flyspray know that its configuration needs to start nginx first to actually work? In systemd, I could just enable it by symlinking nginx into fastcgiwrap@flyspray.service.wants without modifying any service files (though in reality I'd use socket activation). How would you do such a dependency in other systems?