Systemd's socket activation mechanism also got born from the "Sleep is not a synchronisation primitive; talking to a socket is!" and the container world just ig

Systemd's socket activation mechanism also got born from the "Sleep is not a synchronisation primitive; talking to a socket is!" and the container world just ignored it whilst it's a great fit! Actually it's a generalisation of what OP is doing here. Move the listener _out_ of the program and you never have to know if a service is up or not. Connecting to a service just blocks until it's up.