diff --git a/extension.php b/extension.php
index 1431acc..6808cad 100644
--- a/extension.php
+++ b/extension.php
@@ -1,9 +1,9 @@
 <?php
 
-String::extend([
+Text::extend([
   'markdown' => function($text){
     static $markdown_parser = null;
     if (null === $markdown_parser) $markdown_parser = new ParsedownExtra();
     return $markdown_parser->text($text);
   }
-]);
\ No newline at end of file
+]);