diff --git a/run_tests.php b/run_tests.php
old mode 100644
new mode 100755
index 8a93486..459d349
--- a/run_tests.php
+++ b/run_tests.php
@@ -1,3 +1,4 @@
+#!/usr/bin/env php
 <?php
 
 use Symfony\Component\Filesystem\Filesystem;