install: document when offline

diff --git a/install b/install
index dc6b752cfb4759f45a83289652b663263935700f..8fa5d3c6c657072f2b7bea1fdf622b4c7c72becd 100755 (executable)
--- a/install
+++ b/install
@@ -7,6 +7,7 @@ else
   ln -sfn "$PWD/private/root" /root/private
   trap 'git reset private/root' EXIT
   git rm -rf --cached --ignore-unmatch private/root # prevent copying to /nix/store
+  # To build offline, use: --option no-net 1 --option substituters ""
   time nixos-rebuild switch --flake . "$@"
   nix-env --delete-generations +9 --profile /nix/var/nix/profiles/system
 fi