diff --git a/composer.json b/composer.json
index 2198171..410d71d 100644
--- a/composer.json
+++ b/composer.json
@@ -31,8 +31,8 @@
 		"symfony/translation": "~2.0",
 		"symfony/yaml": "~2.0",
 		"symfony/finder": "~2.0",
-		"silverstripe/testsession": "*",
-		"silverstripe/framework": "^4.0.0"
+		"silverstripe/testsession": "^2.0.0-alpha2",
+		"silverstripe/framework": "^4.0.0-alpha2"
 	},
 
 	"autoload": {
diff --git a/src/SilverStripe/BehatExtension/Context/Initializer/SilverStripeAwareInitializer.php b/src/SilverStripe/BehatExtension/Context/Initializer/SilverStripeAwareInitializer.php
index 2058230..24c9730 100644
--- a/src/SilverStripe/BehatExtension/Context/Initializer/SilverStripeAwareInitializer.php
+++ b/src/SilverStripe/BehatExtension/Context/Initializer/SilverStripeAwareInitializer.php
@@ -57,14 +57,19 @@ class SilverStripeAwareInitializer implements InitializerInterface
      */
     protected $testSessionEnvironment;
 
+    /**
+     * @var string PHP file to included before loading Core.php
+     */
+    protected $bootstrapFile;
+
     /**
      * Initializes initializer.
      *
      * @param string $frameworkPath
      */
-    public function __construct($frameworkPath)
+    public function __construct($frameworkPath, $bootstrapFile = null)
     {
-        $this->bootstrap($frameworkPath);
+        $this->bootstrap($frameworkPath, $bootstrapFile);
 
         file_put_contents('php://stdout', "Creating test session environment" . PHP_EOL);
 
@@ -187,10 +192,15 @@ class SilverStripeAwareInitializer implements InitializerInterface
     /**
      * @param string $frameworkPath Absolute path to 'framework' module
      */
-    protected function bootstrap($frameworkPath)
+    protected function bootstrap($frameworkPath, $bootstrapFile = null)
     {
         file_put_contents('php://stdout', 'Bootstrapping' . PHP_EOL);
 
+        // Require a bootstrap file, if provided
+        if ($bootstrapFile) {
+            require_once($bootstrapFile);
+        }
+
         // Connect to database and build manifest
         $_GET['flush'] = 1;
         require_once $frameworkPath . '/Core/Core.php';
diff --git a/src/SilverStripe/BehatExtension/Extension.php b/src/SilverStripe/BehatExtension/Extension.php
index 2144194..33b7606 100644
--- a/src/SilverStripe/BehatExtension/Extension.php
+++ b/src/SilverStripe/BehatExtension/Extension.php
@@ -62,6 +62,7 @@ class Extension implements ExtensionInterface
         if (isset($config['region_map'])) {
             $container->setParameter('behat.silverstripe_extension.region_map', $config['region_map']);
         }
+        $container->setParameter('behat.silverstripe_extension.bootstrap_file', $config['bootstrap_file']);
     }
 
     /**
@@ -102,6 +103,9 @@ class Extension implements ExtensionInterface
                 scalarNode('ajax_timeout')->
                     defaultValue(5000)->
                 end()->
+                scalarNode('bootstrap_file')->
+                    defaultNull()->
+                end()->
                 arrayNode('ajax_steps')->
                     defaultValue(array(
                         'go to',
diff --git a/src/SilverStripe/BehatExtension/services/silverstripe.yml b/src/SilverStripe/BehatExtension/services/silverstripe.yml
index 756e4d0..a204ac7 100644
--- a/src/SilverStripe/BehatExtension/services/silverstripe.yml
+++ b/src/SilverStripe/BehatExtension/services/silverstripe.yml
@@ -18,6 +18,7 @@ services:
     class: %behat.silverstripe_extension.context.initializer.class%
     arguments:
       - %behat.silverstripe_extension.framework_path%
+      - %behat.silverstripe_extension.bootstrap_file%
     calls:
       - [setAjaxSteps, [%behat.silverstripe_extension.ajax_steps%]]
       - [setAjaxTimeout, [%behat.silverstripe_extension.ajax_timeout%]]
@@ -33,4 +34,4 @@ services:
       - %behat.silverstripe_extension.context.namespace_suffix%
       - %behat.context.class%
     tags:
-      - { name: behat.context.class_guesser, priority: 10 }
\ No newline at end of file
+      - { name: behat.context.class_guesser, priority: 10 }