We just had a bunch of fun trying to get it to build right, and the uptime stuff really threw us.
I always check that s6 releases (as well as s6's dependencies) build out-of-the-box on several systems; and that includes FreeBSD, despite it being hell to port to. So if you have an issue with building s6, please submit a precise bug-report.
For my own init system I'm still not sure if the init process should track services and their dependencies at all or just processes and keep the concept of services and dependencies in a service management process instead of the init process.
I strongly recommend writing your service manager as a different process. You don't need it to boot your machine, and anything that's not strictly needed to boot shouldn't be running in process 1. -- Laurent
