In case someone gets the misapprehension that there is a contrast between systemd and launchd in terms of the "well documented" attribution, systemd configuration is also well documented e.g. man systemd.timer etc. I didn't know if launchd has an equivalent of timers, but it does and I've just read `man launchd.plist` "StartCalendarInterval" and compared it with `man systemd.timer` "OnCalendar". I would have said they're about equal. Launchd is more concise, but systemd talks a lot about the interactions with other settings and edge cases.

As for ini vs xml, I've generally found xml is a crueller syntax for humans than ini. At the time I started using systemd, it was a bit funny - the last time I'd been editing ini files was on Windows 3.11. But I think ini and toml are now once again reasonably common so I forgot about how out of place it felt at the time.