diff --git a/avandu.el b/avandu.el
index 4b76de0..175a850 100644
--- a/avandu.el
+++ b/avandu.el
@@ -86,13 +86,15 @@
   "Face for article excerpts in avandu overview."
   :group 'avandu)
 
+(defcustom avandu-tt-rss-api-url nil
+  "URL of your Tiny Tiny RSS instance. For example:
+  http://tt-rss.org/demo/api/"
+  :group 'avandu
+  :type 'string)
+
 (defvar avandu--session-id nil
   "*internal* Session id for avandu.")
 
-(defvar avandu-tt-rss-api-url nil
-  "URL of your Tiny Tiny RSS instance. For example:
-  http://tt-rss.org/demo/api/")
-
 (defvar avandu-user nil
   "Username of your Tiny Tiny RSS account.")