# if you have
den.hosts.x86_64-linux.my-laptop = { ... }
# and then try to use the host conf
den.aspects.my-laptop = { host, ... }: {
nixos.networking.hostName = host.name;
}
It fails saying host was not provided as an argument.
workaround:
den.aspects.my-laptop.includes = let
works = { host, ... }: { nixos.networking.hostName = host.name; };
in [ works ];