diff --git a/init.org b/init.org
index 792ea7b..5ed3de6 100644
--- a/init.org
+++ b/init.org
@@ -3949,6 +3949,25 @@ preceded by another heading) and after headings."
   :hook (org-mode . org-superstar-mode))
 #+END_SRC
 
+*** Automatically add CUSTOM_ID property
+Probably best run in =before-save-hook=. Considerations -
+1. making human-readable CUSTOM_IDs by reusing heading titles
+2. maintaining CUSTOM_ID uniqueness
+
+#+BEGIN_SRC emacs-lisp
+(defun my-org-set-custom-id ()
+  (let (headings)
+    (org-map-region
+     (lambda ()
+       (let ((heading (org-element-at-point)))
+         (unless (org-element-property "CUSTOM_ID" heading)
+           (cl-pushnew (org-element-property :title heading) headings))))
+     (point-min)
+     (point-max))
+    (reverse headings)))
+(add-hook 'org-insert-heading-hook #'my-org-set-custom-id)
+#+END_SRC
+
 ** markdown-mode                                                   :editing:
 #+BEGIN_SRC emacs-lisp
 (use-package markdown-mode