diff --git a/pkgs/nix-tools/darwin-rebuild.sh b/pkgs/nix-tools/darwin-rebuild.sh
index 4f9213c3..bcbb3196 100644
--- a/pkgs/nix-tools/darwin-rebuild.sh
+++ b/pkgs/nix-tools/darwin-rebuild.sh
@@ -114,10 +114,14 @@ if [ "$action" = list -o "$action" = rollback ]; then
   fi
 fi
 
-if [ "$action" = activate -o "$action" = rollback -o "$action" = check ]; then
+if [ "$action" = rollback -o "$action" = check ]; then
   systemConfig="$(cat $profile/systemConfig)"
 fi
 
+if [ "$action" = activate ]; then
+  systemConfig=$(readlink -f "${0%*/sw/bin/darwin-rebuild}")
+fi
+
 if [ -z "$systemConfig" ]; then exit 0; fi
 
 if [ "$action" = switch ]; then