code: private function setImagineService(array $config, ContainerBuilder $container): void
      {
          $imagineServiceId = $config['image']['imagine_service'];
  
          // Generate if not present
          if (null === $imagineServiceId) {
              $class = $this->getImagineImplementation();
              $imagineServiceId = 'contao.image.imagine.'.ContainerBuilder::hash($class);
  
              $container->setDefinition($imagineServiceId, new Definition($class));
          }
  
          $container->setAlias('contao.image.imagine', $imagineServiceId)->setPublic(true);
      }
docs: Configures the "contao.image.imagine" service.