You probably want a virtual filesystem as well. You may want kernel modules. For anything that is not a completely static server you may want some kind of dev

You probably want a virtual filesystem as well. You may want kernel modules. For anything that is not a completely static server you may want some kind of devfs. Then there is the issue of graphics output. Virtual machines require a bit of kernel support. What about container support? Personally I don't like shared libraries, but for people who do you need shared memory support. Multi-threaded programs? Support for multiple CPUs?