Below the kernel is the hardware. QNX is a nanokernel in which the kernel itself is just a tiny executive and all the real work is done in userspace processes, including process management. Pid 1 is procnto, the usespace process manager, and everything else including drivers are userspace processes started and managed by pid 1.
In short, all the interesting stuff actually happens above the kernel, not below. The kernel just does some grunt work of VMM and IPC.
Well. Yes but not exclusively (I am working with QNX since many years), what I meant are the drivers or how resource managers do their job and for which hardware.
Ah, I understand what you said reading it again. You are right, that is "beneath the kernel" not "below".
In short, all the interesting stuff actually happens above the kernel, not below. The kernel just does some grunt work of VMM and IPC.