diff --git a/src/CacheResponse.php b/src/CacheResponse.php
index 5e626ee..71d3309 100644
--- a/src/CacheResponse.php
+++ b/src/CacheResponse.php
@@ -1,11 +1,11 @@
 <?php namespace ostark\upper;
 
-use craft\web\Response;
+use yii\base\Response;
 
 class CacheResponse
 {
     /**
-     * @var \craft\web\Response|\ostark\upper\behaviors\CacheControlBehavior
+     * @var \yii\base\Response|\ostark\upper\behaviors\CacheControlBehavior
      */
     public $response;
 
@@ -16,14 +16,26 @@ public function __construct(Response $response)
 
     public function never()
     {
+        if (!$this->isWebResponse()) {
+            return;
+        }
+
         $this->response->addCacheControlDirective('private');
         $this->response->addCacheControlDirective('no-cache');
     }
 
     public function for(string $time)
     {
+        if (!$this->isWebResponse()) {
+            return;
+        }
+
         $seconds = strtotime($time) - time();
         $this->response->setSharedMaxAge($seconds);
     }
 
+    public function isWebResponse(): bool
+    {
+        return $this->response instanceof \craft\web\Response;
+    }
 }
diff --git a/src/Plugin.php b/src/Plugin.php
index 07739be..fed6e5d 100644
--- a/src/Plugin.php
+++ b/src/Plugin.php
@@ -73,6 +73,9 @@ public function init()
         if ($this->getSettings()->useLocalTags) {
             EventRegistrar::registerFallback();
         }
+
+        // Register Twig extension
+        \Craft::$app->getView()->registerTwigExtension(new TwigExtension);
     }
 
     // ServiceLocators
diff --git a/src/TwigExtension.php b/src/TwigExtension.php
index 4ada220..d27fb58 100644
--- a/src/TwigExtension.php
+++ b/src/TwigExtension.php
@@ -15,7 +15,7 @@ public function getGlobals()
     {
         return [
             'upper' => [
-                'cache' => \Craft::createObject(CacheResponse::class)
+                'cache' => \Craft::createObject(CacheResponse::class, [\Craft::$app->getResponse()]),
             ]
         ];
     }