diff --git a/init.org b/init.org
index 54e2aee..269f6e6 100644
--- a/init.org
+++ b/init.org
@@ -89,6 +89,10 @@ Emacs variables are dynamically scoped. That's unusual for most languages, so di
 
 * Default settings
 #+BEGIN_SRC emacs-lisp
+(defconst *sys/gui*
+  (display-graphic-p)
+  "Is emacs running in a gui?")
+
 (defconst *sys/linux*
   (string-equal system-type 'gnu/linux)
   "Is the system running Linux?")