diff --git a/gnu/services/desktop.scm b/gnu/services/desktop.scm
index e4f0736b89..02bcf1b19f 100644
--- a/gnu/services/desktop.scm
+++ b/gnu/services/desktop.scm
@@ -378,7 +378,7 @@ site} for more information."
 (define polkit-etc-files
   (match-lambda
     (($ <polkit-configuration> polkit packages)
-     `(("polkit-1" ,(polkit-directory packages))))))
+     `(("polkit-1" ,(polkit-directory (cons polkit packages)))))))
 
 (define polkit-setuid-programs
   (match-lambda