100 years ago I wrote a simple sysv init script that started/stopped/queried/enabled/disabled lxc containers, graceful host shutdown (all containers shut down gracefully before the host shuts down), you could start/stop/query/enable/disable individual containers as well as the the meta-service of all containers, all from a few k of bash, and no daemon, not even in the form of a shell loop that stayed running.
Right about then systemd came along (as in, my distro at the time adopted it) and essentially required a service to monitor (some process, tcp port, or file to monitor), but my efficient little script had no service by design, because none was needed and I hate making and running anything that isn't needed to get a given job done. (Plus about that time my company went whole-hog into vmware and a managed service provider and so my infant home-grown lxc containers on colo hardware system never grew past that initial tiny poc)
I laugh so many years later reading "Hey! Check it out! You don't need no steeenkeeeng daemon to run some containers!"
Right about then systemd came along (as in, my distro at the time adopted it) and essentially required a service to monitor (some process, tcp port, or file to monitor), but my efficient little script had no service by design, because none was needed and I hate making and running anything that isn't needed to get a given job done. (Plus about that time my company went whole-hog into vmware and a managed service provider and so my infant home-grown lxc containers on colo hardware system never grew past that initial tiny poc)
I laugh so many years later reading "Hey! Check it out! You don't need no steeenkeeeng daemon to run some containers!"