diff --git a/upgrade.sh b/upgrade.sh
index 19307ac1e1d1..7bd921f3d833 100755
--- a/upgrade.sh
+++ b/upgrade.sh
@@ -4,5 +4,5 @@ if test -z "$NIXOS_CONFIG"; then
 fi
 nix-env -p /nix/var/nix/profiles/system -f configuration/system.nix \
     --arg configuration "import $NIXOS_CONFIG" \
-    -i -A system
+    --set -A system
 /nix/var/nix/profiles/system/bin/switch-to-configuration switch