diff --git a/nixos-infect b/nixos-infect
index eb4daab..68f211e 100755
--- a/nixos-infect
+++ b/nixos-infect
@@ -423,7 +423,7 @@ infect() {
   # see https://github.com/NixOS/nix/issues/3978#issuecomment-952418478
   /root/.nix-profile/bin/nix flake lock ${LOCAL_FLAKE_DIR} \
   --extra-experimental-features "nix-command flakes" \
-  --update-input sp-modules
+  --override-input sp-modules ${LOCAL_FLAKE_DIR}/sp-modules
 
   echo "nix build the configuration flake..."
   if ! /root/.nix-profile/bin/nix build \