diff --git a/controllers/Controller.php b/controllers/Controller.php
index 7012d5d..693cb4c 100644
--- a/controllers/Controller.php
+++ b/controllers/Controller.php
@@ -154,7 +154,7 @@ class Controller {
   }
 
   public function send_a_webmention(Request $request, Response $response) {
-    p3k\session_setup();
+    session_start();
 
     $_SESSION['_csrf'] = random_string(16);