Are OS kernel, driver, and embedded systems development off topic on HN? There were several embedded developer posts in the latest Who's Hiring thread. Web development is by far the largest software segment that HN focuses on, but is by no means the only one.
As an embedded developer/EE, I feel the same way, but from the other side. There is too much breadth for any single person to be proficient at all 7 layers, but from time to time, you still see job descriptions that ask for assembly, C, C++, Java, PHP, HTML, Python, CSS, Flash, Haskell, PCB Layout, VHDL, 7 yrs iOS...