Uselessd
Because systemd was entirely too consistent across environments, so it needed some inconsistency introduced.<p>The documentation reminds me a lot of Emacs's "ANTINEWS", listing all the functionality you lose by downgrading to the previous version of Emacs.  Except in this case, it's actually a "NEWS" file, showing all the functionality you lose by downgrading from systemd to uselessd.<p>> Certain superfluous unit types removed, namely devices, timers, swaps, mounts and automounts.<p>So under uselessd a service or socket file cannot depend on the presence of certain mounts, for instance (RequiresMountsFor=).  Nor can a service run maintenance tasks periodically with supervision on the maintenance task, and with all the privilege-dropping, isolation, and security features easily accomplished with a systemd service.  (And even if a cron implementation implemented such features, they'd work gratuitously differently from systemd services.)  Nor can the availability of a device trigger the reliable, monitored launch of a service with all those same systemd features.<p>> Setup routines for various MAC/ACL systems, including SMACK, IMA and SELinux, are gone. We want to stick to a more clearly defined purpose, one that is agnostic of such elements. Nonetheless, we have retained SELinux access routines in D-Bus APIs and unit options for SMACK attributes in socket unit files to respect existing configurations.<p>So anyone who actually wants to use such security systems is screwed, then.  Good thing Linux isn't about choice.<p>> systemd-fsck has been replaced with a service file that starts /sbin/fsck to fsck devices. In essence, this isn’t much different from what systemd-fsck already did, but with the overhead of a middle man executable interfacing with /sbin/fsck cut out. This also means that the systemd-defined sysctl parameters for its fsck are gone, and you should use the old ones (/forcefsck, etc.) instead.<p>So now, in order to force a check of a filesystem on reboot, you must write to that filesystem, potentially doing further damage to it.