diff --git a/src/Asset/FrontendAsset.php b/src/Asset/FrontendAsset.php
index 5bfb61b..d79a6f7 100644
--- a/src/Asset/FrontendAsset.php
+++ b/src/Asset/FrontendAsset.php
@@ -8,7 +8,7 @@
 
 namespace HeimrichHannot\EncoreBundle\Asset;
 
-class FrontendAsset
+class FrontendAsset implements FrontendAssetInterface
 {
     /**
      * @var array
diff --git a/src/Asset/FrontendAssetInterface.php b/src/Asset/FrontendAssetInterface.php
new file mode 100644
index 0000000..d63819a
--- /dev/null
+++ b/src/Asset/FrontendAssetInterface.php
@@ -0,0 +1,25 @@
+<?php
+
+namespace HeimrichHannot\EncoreBundle\Asset;
+
+interface FrontendAssetInterface
+{
+    /**
+     * Add an active entrypoint.
+     */
+    public function addActiveEntrypoint(string $entrypoint);
+
+    /**
+     * Return a list of all active entrypoints.
+     *
+     * @return array
+     */
+    public function getActiveEntrypoints();
+
+    /**
+     * Check if an entrypoint is set as active entrypoint.
+     *
+     * @return bool
+     */
+    public function isActiveEntrypoint(string $entrypoint);
+}
\ No newline at end of file
diff --git a/src/Asset/GlobalContaoAsset.php b/src/Asset/GlobalContaoAsset.php
index 445e035..a7ca138 100644
--- a/src/Asset/GlobalContaoAsset.php
+++ b/src/Asset/GlobalContaoAsset.php
@@ -11,7 +11,7 @@
 use HeimrichHannot\EncoreBundle\Collection\ExtensionCollection;
 use HeimrichHannot\EncoreContracts\EncoreEntry;
 
-class GlobalContaoAsset
+class GlobalContaoAsset implements GlobalContaoAssetInterface
 {
     private array               $bundleConfig;
     private ExtensionCollection $extensionCollection;
diff --git a/src/Asset/GlobalContaoAssetInterface.php b/src/Asset/GlobalContaoAssetInterface.php
new file mode 100644
index 0000000..49f4acc
--- /dev/null
+++ b/src/Asset/GlobalContaoAssetInterface.php
@@ -0,0 +1,18 @@
+<?php
+
+namespace HeimrichHannot\EncoreBundle\Asset;
+
+interface GlobalContaoAssetInterface
+{
+    public function cleanGlobalArrayFromConfiguration(): void;
+
+    public function cleanFromGlobalArray(string $key, array $entries): void;
+
+    public function cleanJsAssets(array $entries): void;
+
+    public function cleanJqueryAssets(array $entries): void;
+
+    public function cleanCssAssets(array $entries): void;
+
+    public function removeJqueryAsset(): void;
+}
\ No newline at end of file
diff --git a/src/Asset/PageEntrypoints.php b/src/Asset/PageEntrypoints.php
index 537d59a..9acdad4 100644
--- a/src/Asset/PageEntrypoints.php
+++ b/src/Asset/PageEntrypoints.php
@@ -17,7 +17,7 @@
 use HeimrichHannot\UtilsBundle\Model\ModelUtil;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
-class PageEntrypoints
+class PageEntrypoints implements PageEntrypointsInterface
 {
     protected $jsEntries = [];
     protected $cssEntries = [];
@@ -26,15 +26,15 @@ class PageEntrypoints
 
     protected $initialized = false;
 
-    private ContainerInterface $container;
-    private FrontendAsset      $frontendAsset;
-    private EntryCollection    $entryCollection;
-    private ModelUtil          $modelUtil;
+    private ContainerInterface      $container;
+    private FrontendAssetInterface  $frontendAsset;
+    private EntryCollection         $entryCollection;
+    private ModelUtil               $modelUtil;
 
     /**
      * PageEntrypoints constructor.
      */
-    public function __construct(ContainerInterface $container, FrontendAsset $frontendAsset, EntryCollection $entryCollection, ModelUtil $modelUtil)
+    public function __construct(ContainerInterface $container, FrontendAssetInterface $frontendAsset, EntryCollection $entryCollection, ModelUtil $modelUtil)
     {
         $this->container = $container;
         $this->frontendAsset = $frontendAsset;
diff --git a/src/Asset/PageEntrypointsInterface.php b/src/Asset/PageEntrypointsInterface.php
new file mode 100644
index 0000000..0902225
--- /dev/null
+++ b/src/Asset/PageEntrypointsInterface.php
@@ -0,0 +1,48 @@
+<?php
+
+namespace HeimrichHannot\EncoreBundle\Asset;
+
+use Contao\LayoutModel;
+use Contao\PageModel;
+use Exception;
+
+interface PageEntrypointsInterface
+{
+    public function generatePageEntrypoints(PageModel $page, LayoutModel $layout, ?string $encoreField = null): bool;
+
+    /**
+     * Collect all entries for the current page.
+     *
+     * @return array
+     */
+    public function collectPageEntries(LayoutModel $layout, PageModel $currentPage, ?string $encoreField = null);
+
+    /**
+     * @throws Exception
+     */
+    public function getJsEntries(): array;
+
+    /**
+     * @throws Exception
+     */
+    public function getCssEntries(): array;
+
+    /**
+     * @throws Exception
+     */
+    public function getJsHeadEntries(): array;
+
+    /**
+     * Return all active entrypoints.
+     *
+     * @throws Exception
+     */
+    public function getActiveEntries(): array;
+
+    /**
+     * Return a fresh instance of PageEntryPoint.
+     *
+     * @return \HeimrichHannot\EncoreBundle\Asset\PageEntrypoints
+     */
+    public function createInstance();
+}
\ No newline at end of file
diff --git a/src/Asset/TemplateAsset.php b/src/Asset/TemplateAsset.php
index 4d65c39..40aa4dd 100644
--- a/src/Asset/TemplateAsset.php
+++ b/src/Asset/TemplateAsset.php
@@ -14,7 +14,7 @@
 use Twig\Environment;
 use Twig\Error\RuntimeError;
 
-class TemplateAsset
+class TemplateAsset implements TemplateAssetInterface
 {
     /**
      * @var Environment
@@ -25,7 +25,7 @@ class TemplateAsset
      */
     private $layout;
     /**
-     * @var PageEntrypoints
+     * @var PageEntrypointsInterface
      */
     private $pageEntrypoints;
     /**
@@ -53,7 +53,7 @@ class TemplateAsset
      */
     private $webDir;
 
-    public function __construct(array $bundleConfig, string $webDir, Environment $twig, PageEntrypoints $pageEntrypoints)
+    public function __construct(array $bundleConfig, string $webDir, Environment $twig, PageEntrypointsInterface $pageEntrypoints)
     {
         $this->twig = $twig;
         $this->pageEntrypoints = $pageEntrypoints;
diff --git a/src/Asset/TemplateAssetInterface.php b/src/Asset/TemplateAssetInterface.php
new file mode 100644
index 0000000..25de78e
--- /dev/null
+++ b/src/Asset/TemplateAssetInterface.php
@@ -0,0 +1,45 @@
+<?php
+
+namespace HeimrichHannot\EncoreBundle\Asset;
+
+use Contao\LayoutModel;
+use Contao\PageModel;
+
+interface TemplateAssetInterface
+{
+    public function createInstance(PageModel $pageModel, LayoutModel $layoutModel, ?string $entriesField = null): \HeimrichHannot\EncoreBundle\Asset\TemplateAsset;
+
+    public function initialize(PageModel $pageModel, LayoutModel $layoutModel, ?string $entriesField = null);
+
+    /**
+     * Return the javascript that should be included in the header region.
+     *
+     * @throws \Exception
+     */
+    public function headScriptTags(): string;
+
+    /**
+     * Return the javascript tags that should be included in the footer region.
+     *
+     * @throws \Exception
+     */
+    public function scriptTags(): string;
+
+    /**
+     * Return the css link tags that should be included in the header region.
+     *
+     * @return string
+     * @throws \Exception
+     *
+     */
+    public function linkTags();
+
+    /**
+     * Return a link tag with inline css.
+     *
+     * @return bool|string
+     * @throws \Exception
+     *
+     */
+    public function inlineCssLinkTag();
+}
\ No newline at end of file
diff --git a/src/EventListener/Contao/ReplaceDynamicScriptTagsListener.php b/src/EventListener/Contao/ReplaceDynamicScriptTagsListener.php
index ee89ff1..f41c7b9 100644
--- a/src/EventListener/Contao/ReplaceDynamicScriptTagsListener.php
+++ b/src/EventListener/Contao/ReplaceDynamicScriptTagsListener.php
@@ -12,8 +12,8 @@
 use Contao\CoreBundle\ServiceAnnotation\Hook;
 use Contao\LayoutModel;
 use Contao\PageModel;
-use HeimrichHannot\EncoreBundle\Asset\GlobalContaoAsset;
-use HeimrichHannot\EncoreBundle\Asset\TemplateAsset;
+use HeimrichHannot\EncoreBundle\Asset\GlobalContaoAssetInterface;
+use HeimrichHannot\EncoreBundle\Asset\TemplateAssetInterface;
 use HeimrichHannot\EncoreBundle\Helper\ConfigurationHelper;
 use HeimrichHannot\EncoreBundle\Helper\EntryHelper;
 use HeimrichHannot\UtilsBundle\Util\Utils;
@@ -28,21 +28,21 @@ class ReplaceDynamicScriptTagsListener
      */
     protected $bundleConfig;
     /**
-     * @var TemplateAsset
+     * @var TemplateAssetInterface
      */
     protected $templateAsset;
     /**
      * @var ConfigurationHelper
      */
     protected $configurationHelper;
-    private GlobalContaoAsset $globalContaoAsset;
+    private GlobalContaoAssetInterface $globalContaoAsset;
     private ContaoFramework   $contaoFramework;
     private Utils             $utils;
 
     /**
      * ReplaceDynamicScriptTagsListener constructor.
      */
-    public function __construct(array $bundleConfig, ContaoFramework $contaoFramework, Utils $utils, TemplateAsset $templateAsset, ConfigurationHelper $configurationHelper, GlobalContaoAsset $globalContaoAsset)
+    public function __construct(array $bundleConfig, ContaoFramework $contaoFramework, Utils $utils, TemplateAssetInterface $templateAsset, ConfigurationHelper $configurationHelper, GlobalContaoAssetInterface $globalContaoAsset)
     {
         $this->bundleConfig = $bundleConfig;
         $this->templateAsset = $templateAsset;