diff --git a/gnu/services.scm b/gnu/services.scm
index 50be28a382..89c5d52c83 100644
--- a/gnu/services.scm
+++ b/gnu/services.scm
@@ -184,7 +184,7 @@ (define* (fold-service-types proc seed
                                   (if (service-type? object)
                                       (proc object result)
                                       result))
-                                '()
+                                seed
                                 modules))
 
 ;; Services of a given type.