Worst part is "They need signal handlers. " Nothing guarantees that the signal handlers are run, the program may not be in a sane state when it is about to cras

Worst part is "They need signal handlers. " Nothing guarantees that the signal handlers are run, the program may not be in a sane state when it is about to crash from a bug, made worse that it is already hard to write a signal handler correctly without running into any of its API limitations. Basically: signal handlers are not a solution to the problem. If that state is handled by systemd then it needs a way to reset it once the program setting it terminates. If systemd does not have the functionality for that then people are using the wrong tool for the job.