diff --git a/cli-script.php b/cli-script.php
index 5d3cf5cca..b0246ba25 100755
--- a/cli-script.php
+++ b/cli-script.php
@@ -1,149 +1,21 @@
 <?php
 
-use SilverStripe\Control\Director;
-use SilverStripe\ORM\DB;
+// CLI specific bootstrapping
+use SilverStripe\Core\AppKernel;
+use SilverStripe\Core\HTTPApplication;
+use SilverStripe\Core\Startup\OutputMiddleware;
+use SilverStripe\Control\HTTPRequest;
 
-
-/**
- * File similar to main.php designed for command-line scripts
- *
- * This file lets you execute SilverStripe requests from the command-line.  The URL is passed as the first argument to
- * the scripts.
- */
-
-/**
- * Ensure that people can't access this from a web-server
- */
-if(PHP_SAPI != "cli" && PHP_SAPI  != "cgi" && PHP_SAPI != "cgi-fcgi") {
-	echo "cli-script.php can't be run from a web request, you have to run it on the command-line.";
-	die();
-}
-
-// We update the $_SERVER variable to contain data consistent with the rest of the application.
-$_SERVER = array_merge(array(
-    'SERVER_PROTOCOL' => 'HTTP/1.1',
-    'HTTP_ACCEPT' => 'text/plain;q=0.5',
-    'HTTP_ACCEPT_LANGUAGE' => '*;q=0.5',
-    'HTTP_ACCEPT_ENCODING' => '',
-    'HTTP_ACCEPT_CHARSET' => 'ISO-8859-1;q=0.5',
-    'SERVER_SIGNATURE' => 'Command-line PHP/' . phpversion(),
-    'SERVER_SOFTWARE' => 'PHP/' . phpversion(),
-    'SERVER_ADDR' => '127.0.0.1',
-    'REMOTE_ADDR' => '127.0.0.1',
-    'REQUEST_METHOD' => 'GET',
-    'HTTP_USER_AGENT' => 'CLI',
-), $_SERVER);
-
-/**
- * Identify the cli-script.php file and change to its container directory, so that require_once() works
- */
+require __DIR__ . '/src/includes/cli.php';
 $_SERVER['SCRIPT_FILENAME'] = __FILE__;
-chdir(dirname($_SERVER['SCRIPT_FILENAME']));
-
-/**
- * Process arguments and load them into the $_GET and $_REQUEST arrays
- * For example,
- * sake my/url somearg otherarg key=val --otherkey=val third=val&fourth=val
- *
- * Will result in the following get data:
- *   args => array('somearg', 'otherarg'),
- *   key => val
- *   otherkey => val
- *   third => val
- *   fourth => val
- */
-if(isset($_SERVER['argv'][2])) {
-	$args = array_slice($_SERVER['argv'],2);
-	if(!isset($_GET)) $_GET = array();
-	if(!isset($_REQUEST)) $_REQUEST = array();
-	foreach($args as $arg) {
-		if(strpos($arg,'=') == false) {
-			$_GET['args'][] = $arg;
-		} else {
-			$newItems = array();
-			parse_str( (substr($arg,0,2) == '--') ? substr($arg,2) : $arg, $newItems );
-			$_GET = array_merge($_GET, $newItems);
-		}
-	}
-	$_REQUEST = array_merge($_REQUEST, $_GET);
-}
-
-// Set 'url' GET parameter
-if(isset($_SERVER['argv'][1])) {
-	$_REQUEST['url'] = $_SERVER['argv'][1];
-	$_GET['url'] = $_SERVER['argv'][1];
-}
-
-// require composers autoloader
-if (file_exists($autoloadPath = dirname(__DIR__) . '/vendor/autoload.php')) {
-	require_once $autoloadPath;
-}
-else  {
-	echo "Failed to include composer's autoloader, unable to continue\n";
-	exit(1);
-}
-
-/**
- * Include SilverStripe's core code
- */
-require_once("Core/Core.php");
-
-global $databaseConfig;
-
-// We don't have a session in cli-script, but this prevents errors
-$_SESSION = null;
-
-// Connect to database
-if(!isset($databaseConfig) || !isset($databaseConfig['database']) || !$databaseConfig['database']) {
-	echo "\nPlease configure your database connection details.  You can do this by creating a file
-called .env in " . BASE_PATH;
-	echo <<<ENVCONTENT
-
-Put the following content into this file:
---------------------------------------------------
-
-# Change this from 'dev' to 'live' for a production environment.
-SS_ENVIRONMENT_TYPE="dev"
-
-/* This defines a default database user */
-SS_DATABASE_SERVER="localhost"
-SS_DATABASE_USERNAME="<user>"
-SS_DATABASE_PASSWORD="<password>"
-SS_DATABASE_NAME="<database>"
---------------------------------------------------
-
-Once you have done that, run 'composer install' or './framework/sake dev/build' to create
-an empty database.
-
-For more information, please read this page in our docs:
-http://docs.silverstripe.org/en/getting_started/environment_management/
+chdir(__DIR__);
 
 
-ENVCONTENT;
-	exit(1);
-}
-DB::connect($databaseConfig);
-
-// register_argc_argv: Tells PHP whether to declare the argv & argc variables (that would contain the GET information)
-// http://php.net/manual/en/ini.core.php#ini.register-argc-argv
-if (!(int)ini_get('register_argc_argv')) {
-	echo 'register_argc_argv is required to obtain the GET information but is disabled.'
-	    .'Please enable it in your php.ini ('
-		. php_ini_loaded_file()
-        .')';
-    die();
-}
-
-// Get the request URL from the querystring arguments
-$url = isset($_SERVER['argv'][1]) ? $_SERVER['argv'][1] : null;
-if(!$url) {
-	echo 'Please specify an argument to cli-script.php/sake. For more information, visit'
-		. ' http://docs.silverstripe.org/en/developer_guides/cli' . "\n";
-	die();
-}
-
-$_SERVER['REQUEST_URI'] = BASE_URL . '/' . $url;
-
-Director::direct($url);
-
+require __DIR__ . '/src/includes/autoload.php';
 
+// Default application
+$request = HTTPRequest::createFromEnvironment();
+$kernel = new AppKernel();
+$app = new HTTPApplication($kernel);
+$app->addMiddleware(new OutputMiddleware());
+$app->handle($request);
diff --git a/main.php b/main.php
index 3912a107d..be8476b4c 100644
--- a/main.php
+++ b/main.php
@@ -1,14 +1,5 @@
 <?php
 
-/************************************************************************************
- ************************************************************************************
- **                                                                                **
- **  If you can read this text in your browser then you don't have PHP installed.  **
- **  Please install PHP 5.6.0 or higher                                            **
- **                                                                                **
- ************************************************************************************
- ************************************************************************************/
-
 use SilverStripe\Core\AppKernel;
 use SilverStripe\Core\HTTPApplication;
 use SilverStripe\Core\Startup\ErrorControlChainMiddleware;
diff --git a/src/Control/HTTPRequest.php b/src/Control/HTTPRequest.php
index f0b801ab5..9eb6b24d6 100644
--- a/src/Control/HTTPRequest.php
+++ b/src/Control/HTTPRequest.php
@@ -2,6 +2,7 @@
 
 namespace SilverStripe\Control;
 
+use BadMethodCallException;
 use SilverStripe\Core\ClassInfo;
 use SilverStripe\ORM\ArrayLib;
 use ArrayAccess;
@@ -1053,6 +1054,9 @@ class HTTPRequest implements ArrayAccess
      */
     public function getSession()
     {
+        if (empty($this->session)) {
+            throw new BadMethodCallException("No session available for this HTTPRequest");
+        }
         return $this->session;
     }
 
diff --git a/src/Core/Startup/OutputMiddleware.php b/src/Core/Startup/OutputMiddleware.php
index 9a81432a2..d04a349ca 100644
--- a/src/Core/Startup/OutputMiddleware.php
+++ b/src/Core/Startup/OutputMiddleware.php
@@ -3,6 +3,7 @@
 namespace SilverStripe\Core\Startup;
 
 use SilverStripe\Control\HTTPResponse;
+use SilverStripe\Control\HTTPResponse_Exception;
 
 /**
  * Emits response to the browser
@@ -26,7 +27,11 @@ class OutputMiddleware
     public function __invoke(callable $next)
     {
         /** @var HTTPResponse $response */
-        $response = call_user_func($next);
+        try {
+            $response = call_user_func($next);
+        } catch (HTTPResponse_Exception $exception) {
+            $response = $exception->getResponse();
+        }
         if ($response) {
             $response->output();
         } elseif ($this->defaultResponse) {
diff --git a/src/includes/autoload.php b/src/includes/autoload.php
index 1de9618ab..4a1af9117 100644
--- a/src/includes/autoload.php
+++ b/src/includes/autoload.php
@@ -1,16 +1,5 @@
 <?php
 
-// Check PHP version
-if (version_compare(phpversion(), '5.6.0', '<')) {
-    header($_SERVER['SERVER_PROTOCOL'] . " 500 Server Error");
-    echo str_replace(
-        '$PHPVersion',
-        phpversion(),
-        file_get_contents(__DIR__ . "/../Dev/Install/php5-required.html")
-    );
-    die();
-}
-
 // Init composer autoload
 call_user_func(function () {
     $candidates = [
diff --git a/src/includes/cli.php b/src/includes/cli.php
new file mode 100644
index 000000000..2b24f78b8
--- /dev/null
+++ b/src/includes/cli.php
@@ -0,0 +1,64 @@
+<?php
+
+// Mock HTTP globals in CLI environment
+
+// Ensure that people can't access this from a web-server
+if (PHP_SAPI != "cli" && PHP_SAPI != "cgi" && PHP_SAPI != "cgi-fcgi") {
+    echo "cli-script.php can't be run from a web request, you have to run it on the command-line.";
+    die();
+}
+
+// We update the $_SERVER variable to contain data consistent with the rest of the application.
+$_SERVER = array_merge(array(
+    'SERVER_PROTOCOL' => 'HTTP/1.1',
+    'HTTP_ACCEPT' => 'text/plain;q=0.5',
+    'HTTP_ACCEPT_LANGUAGE' => '*;q=0.5',
+    'HTTP_ACCEPT_ENCODING' => '',
+    'HTTP_ACCEPT_CHARSET' => 'ISO-8859-1;q=0.5',
+    'SERVER_SIGNATURE' => 'Command-line PHP/' . phpversion(),
+    'SERVER_SOFTWARE' => 'PHP/' . phpversion(),
+    'SERVER_ADDR' => '127.0.0.1',
+    'REMOTE_ADDR' => '127.0.0.1',
+    'REQUEST_METHOD' => 'GET',
+    'HTTP_USER_AGENT' => 'CLI',
+), $_SERVER);
+
+/**
+ * Process arguments and load them into the $_GET and $_REQUEST arrays
+ * For example,
+ * sake my/url somearg otherarg key=val --otherkey=val third=val&fourth=val
+ *
+ * Will result in the following get data:
+ *   args => array('somearg', 'otherarg'),
+ *   key => val
+ *   otherkey => val
+ *   third => val
+ *   fourth => val
+ */
+if (isset($_SERVER['argv'][2])) {
+    call_user_func(function () {
+        $args = array_slice($_SERVER['argv'], 2);
+        if (!isset($_GET)) {
+            $_GET = array();
+        }
+        if (!isset($_REQUEST)) {
+            $_REQUEST = array();
+        }
+        foreach ($args as $arg) {
+            if (strpos($arg, '=') == false) {
+                $_GET['args'][] = $arg;
+            } else {
+                $newItems = array();
+                parse_str((substr($arg, 0, 2) == '--') ? substr($arg, 2) : $arg, $newItems);
+                $_GET = array_merge($_GET, $newItems);
+            }
+        }
+        $_REQUEST = array_merge($_REQUEST, $_GET);
+    });
+}
+
+// Set 'url' GET parameter
+if (isset($_SERVER['argv'][1])) {
+    $_REQUEST['url'] = $_SERVER['argv'][1];
+    $_GET['url'] = $_SERVER['argv'][1];
+}