If that's your definition, then FreeBSD and Solaris solved this without paying the systemd tax, via ZFS-based boot environments.
https://www.freebsd.org/cgi/man.cgi?query=beadm&sektion=&man...
NeXt->Apple also avoided anything like systemd via a configuration system that supported inheritance across search domains (User, Local, Network, System):
https://developer.apple.com/library/mac/documentation/Cocoa/...