futtern/config/services.php

<?php declare(strict_types=1);

use Symfony\Bridge\Twig\AppVariable;
use Symfony\Component\DependencyInjection\Loader\Configurator\ContainerConfigurator;

return static function (ContainerConfigurator $containerConfigurator): void {
    $services = $containerConfigurator->services();
    $services->defaults()
        ->autowire()
        ->autoconfigure();
    $services
        ->load('App\\', __DIR__ . '/../src/')
        ->exclude([
            __DIR__ . '/../src/DependencyInjection/',
            __DIR__ . '/../src/Entity/',
            __DIR__ . '/../src/Kernel.php',
        ]);
    $services->alias(AppVariable::class, 'twig.app_variable');
};