diff --git a/autoload-fast.php b/autoload-fast.php
index b5e47cf6..fceacbd9 100644
--- a/autoload-fast.php
+++ b/autoload-fast.php
@@ -1,4 +1,4 @@
 <?php
 
-require_once DIRNAME(__FILE__) . '/autoload.php';
+require_once dirname(__FILE__) . '/autoload.php';
 ParagonIE_Sodium_Compat::$fastMult = true;