use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
+use Doctrine\Persistence\ManagerRegistry;

 final class SomeController extends AbstractController
 {
+    public function __construct(
+        private ManagerRegistry $managerRegistry
+    ) {
+    }
+
     public function run()
     {
-        $productRepository = $this->getDoctrine()->getRepository(Product::class);
+        $productRepository = $this->managerRegistry->getRepository(Product::class);
     }
 }

 use Symfony\Bundle\FrameworkBundle\Test\KernelTestCase;

 class SomeTest extends KernelTestCase
 {
     protected function setUp(): void
     {
-        $container = self::$container;
+        $container = self::getContainer();
     }
 }

 use Symfony\Bundle\FrameworkBundle\Kernel\MicroKernelTrait;
 use Symfony\Component\HttpKernel\Kernel;
-use Symfony\Component\Routing\RouteCollectionBuilder;
+use Symfony\Component\Routing\Loader\Configurator\RoutingConfigurator;

 final class ConcreteMicroKernel extends Kernel
 {
     use MicroKernelTrait;

-    protected function configureRoutes(RouteCollectionBuilder $routes)
+    protected function configureRouting(RoutingConfigurator $routes): void
     {
-        $routes->add('/admin', 'App\Controller\AdminController::dashboard', 'admin_dashboard');
-    }
-}
+        $routes->add('admin_dashboard', '/admin')
+            ->controller('App\Controller\AdminController::dashboard')
+    }}

 use Symfony\Bundle\FrameworkBundle\Controller\Controller;

 class BaseController extends Controller
 {
     function indexAction()
     {
-        $this->render('appBundle:Landing\Main:index.html.twig');
+        $this->render('@app/Landing/Main/index.html.twig');
     }
 }

 use Symfony\Bundle\FrameworkBundle\Controller\Controller;

 final class SomeController extends Controller
 {
     public function action()
     {
-        $form = $this->createForm(new TeamType);
+        $form = $this->createForm(TeamType::class);
     }
 }

 use Symfony\Bundle\FrameworkBundle\Controller\Controller;

 final class SomeController extend Controller
 {
+    public function __construct(SomeService $someService)
+    {
+        $this->someService = $someService;
+    }
+
     public function someMethod()
     {
-        // ...
-        $this->get('some_service');
+        $this->someService;
     }
 }

-$this->redirect($this->generateUrl("homepage"));
+$this->redirectToRoute("homepage");

+use Symfony\Component\HttpFoundation\Request;
+
 class SomeController
 {
-    public function someAction()
+    public function someAction(Request $request)
     {
-        return $this->getRequest()->getContent();
+        return $request->getContent();
     }
 }