not-os

toplevel

$ nix-build -A toplevel
/nix/store/zi6a3i50k6ym6xxrmmlrvrfcfgr9bwsb-toplevel

The toplevel contains two scripts and a directory (actually a symlink):

$ ls /nix/store/q40j6y70nwhgazvhzrlzh79cjlfik7jv-not-os/
activate  init  sw

The toplevel is packaged as a squashfs image.

The toplevel’s path is sometimes called systemConfig or sysconfig.