diff --git a/lisp/progmodes/ruby-ts-mode.el b/lisp/progmodes/ruby-ts-mode.el
index 71562b46306..da2d00ce168 100644
--- a/lisp/progmodes/ruby-ts-mode.el
+++ b/lisp/progmodes/ruby-ts-mode.el
@@ -71,6 +71,8 @@
 ;; ruby-ts-mode tries to adhere to the indentation related user
 ;; options from ruby-mode, such as ruby-indent-level,
 ;; ruby-indent-tabs-mode, and so on.
+;;
+;; Type 'M-x customize-group RET ruby RET' to see the options.
 
 ;; * IMenu
 ;; * Navigation