The question that is coming increasingly urgent for me is, what is the simplest system that can meet my need for X over Y time period? Systems in the field mig

The question that is coming increasingly urgent for me is, what is the simplest system that can meet my need for X over Y time period? Systems in the field might run for ten years and get patched only rarely even as the line cards or PSUs or whatever get replaced underneath them. I need things like A/B OS images, bulletproof but grokable IP stack and tools, and a userspace that can be shrunk down to as little as I want, when I want. No little obscure binaries left on the disk, everything must only be there because I want it there. I am increasingly drawn to the BSDs, as the idea of subtracting big chunks of Linux in order to build an OS base for such platforms is frankly terrifying. (Hence, busybox and friends, but thats only a small part of the solution.) BSDs seem to do a better job of identifying what is essential and what is not, and the development seems less gigantically complex (Linux is rather Borg-like today, not like in 1995.)