diff --git a/bin/console b/bin/console
index d8d530e..a0b67ba 100755
--- a/bin/console
+++ b/bin/console
@@ -14,7 +14,7 @@ if (!is_file(dirname(__DIR__).'/vendor/autoload_runtime.php')) {
 
 require_once dirname(__DIR__).'/vendor/autoload_runtime.php';
 
-return function (array $context) {
+return static function (array $context) {
     $kernel = new Kernel($context['APP_ENV'], (bool) $context['APP_DEBUG']);
 
     return new Application($kernel);
diff --git a/composer.json b/composer.json
index 95e3d4d..83b176f 100644
--- a/composer.json
+++ b/composer.json
@@ -10,6 +10,7 @@
         "ext-ctype": "*",
         "ext-iconv": "*",
         "ext-redis": "*",
+        "ext-zend-opcache": "*",
         "symfony/asset": "8.1.*",
         "symfony/asset-mapper": "8.1.*",
         "symfony/cache": "8.1.*",
diff --git a/composer.lock b/composer.lock
index 090929d..5dd3d5c 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "96e1f33a9305b01c5a60a23677f28c09",
+    "content-hash": "47f5a956caee19d61ae3aee269641fff",
     "packages": [
         {
             "name": "composer/semver",
@@ -4273,7 +4273,8 @@
         "php": ">=8.2",
         "ext-ctype": "*",
         "ext-iconv": "*",
-        "ext-redis": "*"
+        "ext-redis": "*",
+        "ext-zend-opcache": "*"
     },
     "platform-dev": {},
     "plugin-api-version": "2.9.0"
diff --git a/config/preload.php b/config/preload.php
index 5ebcdb2..4d4360d 100644
--- a/config/preload.php
+++ b/config/preload.php
@@ -1,5 +1,5 @@
 <?php
 
 if (file_exists(dirname(__DIR__).'/var/cache/prod/App_KernelProdContainer.preload.php')) {
-    require dirname(__DIR__).'/var/cache/prod/App_KernelProdContainer.preload.php';
+    opcache_compile_file(dirname(__DIR__) . '/var/cache/prod/App_KernelProdContainer.preload.php');
 }
diff --git a/importmap.php b/importmap.php
index 70ebf14..7d9c28b 100644
--- a/importmap.php
+++ b/importmap.php
@@ -10,10 +10,22 @@
  *     be used as an "entrypoint" (and passed to the importmap() Twig function).
  *
  * The "importmap:require" command can be used to add new entries to this file.
+ *
+ * @return array<string, array{    // Import name as key, description of the imported file as value
+ *     path: string,               // Logical, relative or absolute path to the file
+ *     type?: 'js'|'css'|'json',   // Type of the file, defaults to 'js'
+ *     entrypoint?: bool,          // Whether the file is an entrypoint, for 'js' only
+ * }|array{
+ *     version: string,            // Version of the remote package
+ *     package_specifier?: string, // Remote "package-name/path" specifier, defaults to the import name
+ *     type?: 'js'|'css'|'json',
+ *     entrypoint?: bool,
+ * }>
  */
 return [
-    'app' => [
-        'path' => './assets/app.js',
-        'entrypoint' => true,
-    ],
+    'app' => ['path' => './assets/app.js', 'entrypoint' => true],
+    '@symfony/webpack-encore' => ['version' => '6.0.0'],
+    'bootstrap' => ['version' => '5.3.8'],
+    '@popperjs/core' => ['version' => '2.11.8'],
+    'bootstrap/dist/css/bootstrap.min.css' => ['version' => '5.3.8', 'type' => 'css'],
 ];
diff --git a/public/index.php b/public/index.php
index 9982c21..c0037a8 100644
--- a/public/index.php
+++ b/public/index.php
@@ -4,6 +4,6 @@ use App\Kernel;
 
 require_once dirname(__DIR__).'/vendor/autoload_runtime.php';
 
-return function (array $context) {
+return static function (array $context) {
     return new Kernel($context['APP_ENV'], (bool) $context['APP_DEBUG']);
 };