diff --git a/_config/processors.yml b/_config/processors.yml
index d52ef3c..eac4898 100644
--- a/_config/processors.yml
+++ b/_config/processors.yml
@@ -1,8 +1,12 @@
 ---
 Name: testsessionprocessors
+After:
+  - requestprocessors
+Before:
+  - coresecurity
 ---
 SilverStripe\Core\Injector\Injector:
-  SilverStripe\Control\RequestProcessor:
+  SilverStripe\Control\Director:
     properties:
-      filters:
-        - '%$SilverStripe\TestSession\TestSessionRequestFilter'
+      Middlewares:
+        TestSessionHTTPMiddleware: %$SilverStripe\TestSession\TestSessionHTTPMiddleware
diff --git a/composer.json b/composer.json
index 9627fb2..9594136 100644
--- a/composer.json
+++ b/composer.json
@@ -20,7 +20,7 @@
   },
   "extra": {
     "branch-alias": {
-      "dev-master": "2.x-dev"
+      "dev-master": "2.0.x-dev"
     }
   },
   "scripts": {
diff --git a/src/TestSessionController.php b/src/TestSessionController.php
index 1f862f5..8cfe67e 100644
--- a/src/TestSessionController.php
+++ b/src/TestSessionController.php
@@ -2,11 +2,12 @@
 
 namespace SilverStripe\TestSession;
 
+use FilesystemIterator;
+use LogicException;
 use SilverStripe\Control\Controller;
 use SilverStripe\Control\Director;
 use SilverStripe\Control\HTTPRequest;
 use SilverStripe\Core\Injector\Injector;
-use SilverStripe\Dev\SapphireTest;
 use SilverStripe\Forms\CheckboxField;
 use SilverStripe\Forms\DatetimeField;
 use SilverStripe\Forms\DropdownField;
@@ -24,8 +25,6 @@ use SilverStripe\Security\RandomGenerator;
 use SilverStripe\Security\Security;
 use SilverStripe\View\ArrayData;
 use SilverStripe\View\Requirements;
-use LogicException;
-use FilesystemIterator;
 
 /**
  * Requires PHP's mycrypt extension in order to set the database name as an encrypted cookie.
diff --git a/src/TestSessionEnvironment.php b/src/TestSessionEnvironment.php
index 19f945c..39b3324 100644
--- a/src/TestSessionEnvironment.php
+++ b/src/TestSessionEnvironment.php
@@ -85,7 +85,7 @@ class TestSessionEnvironment
     public function init(HTTPRequest $request)
     {
         if (!$this->id) {
-            $request->getSession()->init();
+            $request->getSession()->init($request);
             // $_SESSION != Session::get() in some execution paths, suspect Controller->pushCurrent()
             // as part of the issue, easiest resolution is to use session directly for now
             $this->id = $request->getSession()->get('TestSessionId');
@@ -98,9 +98,9 @@ class TestSessionEnvironment
     public function getFilePath()
     {
         if ($this->id) {
-            $path = Director::getAbsFile(sprintf($this->config()->test_state_id_file, $this->id));
+            $path = Director::getAbsFile(sprintf($this->config()->get('test_state_id_file'), $this->id));
         } else {
-            $path = Director::getAbsFile($this->config()->test_state_file);
+            $path = Director::getAbsFile($this->config()->get('test_state_file'));
         }
 
         return $path;
diff --git a/src/TestSessionRequestFilter.php b/src/TestSessionHTTPMiddleware.php
similarity index 74%
rename from src/TestSessionRequestFilter.php
rename to src/TestSessionHTTPMiddleware.php
index cda508c..c75bc38 100644
--- a/src/TestSessionRequestFilter.php
+++ b/src/TestSessionHTTPMiddleware.php
@@ -6,8 +6,7 @@ use SilverStripe\Control\Director;
 use SilverStripe\Control\Email\Email;
 use SilverStripe\Control\Email\Mailer;
 use SilverStripe\Control\HTTPRequest;
-use SilverStripe\Control\HTTPResponse;
-use SilverStripe\Control\RequestFilter;
+use SilverStripe\Control\Middleware\HTTPMiddleware;
 use SilverStripe\Core\Injector\Injector;
 use SilverStripe\ORM\DB;
 use SilverStripe\ORM\FieldType\DBDatetime;
@@ -15,7 +14,7 @@ use SilverStripe\ORM\FieldType\DBDatetime;
 /**
  * Sets state previously initialized through {@link TestSessionController}.
  */
-class TestSessionRequestFilter implements RequestFilter
+class TestSessionHTTPMiddleware implements HTTPMiddleware
 {
     /**
      * @var TestSessionEnvironment
@@ -27,14 +26,35 @@ class TestSessionRequestFilter implements RequestFilter
         $this->testSessionEnvironment = TestSessionEnvironment::singleton();
     }
 
-    public function preRequest(HTTPRequest $request)
+    public function process(HTTPRequest $request, callable $delegate)
     {
-        $isRunningTests = $this->testSessionEnvironment->isRunningTests();
+        // Init environment
         $this->testSessionEnvironment->init($request);
+
+        // If not running tests, just pass through
+        $isRunningTests = $this->testSessionEnvironment->isRunningTests();
         if (!$isRunningTests) {
-            return;
+            return $delegate($request);
         }
 
+        // Load test state
+        $this->loadTestState($request);
+
+        // Call with safe teardown
+        try {
+            return $delegate($request);
+        } finally {
+            $this->restoreTestState($request);
+        }
+    }
+
+    /**
+     * Load test state from environment into "real" environment
+     *
+     * @param HTTPRequest $request
+     */
+    protected function loadTestState(HTTPRequest $request)
+    {
         $testState = $this->testSessionEnvironment->getState();
 
         // Date and time
@@ -67,12 +87,8 @@ class TestSessionRequestFilter implements RequestFilter
         }
     }
 
-    public function postRequest(HTTPRequest $request, HTTPResponse $response)
+    protected function restoreTestState(HTTPRequest $request)
     {
-        if (!$this->testSessionEnvironment->isRunningTests()) {
-            return;
-        }
-
         // Store PHP session
         $state = $this->testSessionEnvironment->getState();
         $state->session = $request->getSession()->getAll();