VoidLinux uses runit for its init system and service manager. But something that is nice about runit is that you dont have to use it for both of those things! You can use it as just a service manager without any of the init system stuff. We could make VoidPup launch the service management part called runsvdir to run service scripts from void packages installed with vpm.
Something I have done on my fossapup install is that I have my /etc/inittab set up to launch runsvdir to manage some runit services I have written to use over there. We could also do this in VoidPup in a way compatible with how void usually uses runit to make it so runit services from installed void packages would work correctly.
Alternatively I could make a sysvinit script to put in /etc/init.d to run runsvdir from there. Maybe there's an advantage there to make sure it runs only once the startup sequence gets to rc.services. (I'm not really sure if my inittab is waiting until after the main puppy startup is done to run runsvdir or not)
Anywayl if any of that is something you are interested in I could get it working and share those changes.
If i did this it might also be nice to make a GUI for managing which runit services are enabled or disabled. runit is pretty simple and mainly just works on whether a file is symlinked somewhere or if the "down" file exists, so this would not be too complicated for me to do