diff --git a/autoload.php b/autoload.php
index 1e5ad34..0c502f1 100644
--- a/autoload.php
+++ b/autoload.php
@@ -11,4 +11,4 @@
  * @see core/modules/statistics/statistics.php
  */
 
-return require __DIR__ . '/vendor/autoload.php';
+return include __DIR__ . '/vendor/autoload.php';
diff --git a/index.php b/index.php
index 750dc28..a3c3c22 100644
--- a/index.php
+++ b/index.php
@@ -13,6 +13,12 @@
 
 $autoloader = require_once 'autoload.php';
 
+if (!class_exists('\Drupal\Core\DrupalKernel')) {
+  header('500 Internal Server Error');
+  print("We can't find DrupalKernel class which is usually an indication that composer install hasn't been run. Refer to <a href='https://www.drupal.org/documentation/install/download#git'>this page</a> for more details.");
+  exit;
+}
+
 $kernel = new DrupalKernel('prod', $autoloader);
 
 $request = Request::createFromGlobals();