diff --git a/ci/nixpkgs-vet.sh b/ci/nixpkgs-vet.sh
index 8ad2a35adfa0..7d6cebc6bfd8 100755
--- a/ci/nixpkgs-vet.sh
+++ b/ci/nixpkgs-vet.sh
@@ -63,4 +63,4 @@ git -C "$tmp/merged" merge -q --no-edit "$baseSha"
 trace -e "\e[34m$(git -C "$tmp/merged" rev-parse HEAD)\e[0m"
 
 trace "Running nixpkgs-vet.."
-nix-build ci -A nixpkgs-vet --argstr base "$tmp/base" --argstr head "$tmp/merged"
+nix-build ci -A nixpkgs-vet --arg base "$tmp/base" --arg head "$tmp/merged"