diff --git a/private_includes/base/markup_tag_groups_hack.ily b/private_includes/base/markup_tag_groups_hack.ily
index 7832806..9bd49b6 100644
--- a/private_includes/base/markup_tag_groups_hack.ily
+++ b/private_includes/base/markup_tag_groups_hack.ily
@@ -9,5 +9,8 @@ tagGroup =
 
 #(define-markup-command (handle-tag-groups layout props recorded-groups m) (list? markup?)
    (resetTagGroups)
-   (every (lambda (group) (define-tag-group group)) recorded-groups)
+   (for-each
+     (lambda (group)
+       (define-tag-group group))
+     recorded-groups)
    (interpret-markup layout props m))