diff --git a/scripts/codex-setup.sh b/scripts/codex-setup.sh
index 957a612..0f114fc 100755
--- a/scripts/codex-setup.sh
+++ b/scripts/codex-setup.sh
@@ -68,6 +68,7 @@ cat > "$HOME/.config/nix/nix.conf" <<'EOF'
 experimental-features = nix-command flakes
 accept-flake-config = false
 warn-dirty = false
+build-users-group =
 EOF
 
 echo "Nix version:"