[root@dent:/etc/nixos]# nixos-rebuild boot --show-trace
building Nix...
building the system configuration...
error: while evaluating the attribute 'config.system.build.toplevel' at /nix/var/nix/profiles/per-user/root/channels/nixos/nixos/modules/system/activation/top-level.nix:275:5:
while evaluating 'foldr' at /nix/var/nix/profiles/per-user/root/channels/nixos/lib/lists.nix:52:20, called from /nix/var/nix/profiles/per-user/root/channels/nixos/nixos/modules/system/activation/top-level.nix:139:12:
while evaluating 'fold'' at /nix/var/nix/profiles/per-user/root/channels/nixos/lib/lists.nix:55:15, called from /nix/var/nix/profiles/per-user/root/channels/nixos/lib/lists.nix:59:8:
while evaluating anonymous function at /nix/var/nix/profiles/per-user/root/channels/nixos/nixos/modules/system/activation/top-level.nix:132:50, called from undefined position:
while evaluating the attribute 'assertion' at /nix/store/26s6bkfh6gvq0zg0a9lgjs6p4i66r1hx-source/nixos.nix:190:11:
while evaluating 'markedNeededForBoot' at /nix/store/26s6bkfh6gvq0zg0a9lgjs6p4i66r1hx-source/nixos.nix:168:37, called from /nix/store/26s6bkfh6gvq0zg0a9lgjs6p4i66r1hx-source/nixos.nix:190:23:
while evaluating the attribute 'fileSystems."/nix/persist".neededForBoot' at undefined position:
attribute '/nix/persist' missing, at /nix/store/26s6bkfh6gvq0zg0a9lgjs6p4i66r1hx-source/nixos.nix:168:42