what is... actually wrong with that?

it works, it's extensible, and a simple service is just as declarative as systemd, but when you need to do something more complex (e.g. checking conditions before starting), you don't need to create a separate script to do so or pile up 10 ExecStartPre lines, just `start_pre() { ... }` away

i've seen people again and again complain of "but shell scripts", while the default functions provide an interface with declarative variables right there, what is the actual issue with it?