Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires matthiasnoback/symfony-dependency-injection-test ^6.0 -> satisfiable by matthiasnoback/symfony-dependency-injection-test[6.0.0]. - matthiasnoback/symfony-dependency-injection-test 6.0.0 requires phpunit/phpunit ^10.5.11 || ^11.0 -> found phpunit/phpunit[10.5.11, ..., 10.5.45, 11.0.0, ..., 11.5.7] but it conflicts with your root composer.json require (^12.0). Problem 2 - Root composer.json requires matthiasnoback/symfony-config-test ^5.1 -> satisfiable by matthiasnoback/symfony-config-test[v5.1.0, v5.2.0]. - Root composer.json requires phpunit/phpunit ^12.0 -> satisfiable by phpunit/phpunit[12.0.0, 12.0.1]. - matthiasnoback/symfony-config-test v5.1.0 conflicts with phpunit/phpunit 12.0.1. - matthiasnoback/symfony-config-test v5.2.0 requires phpunit/phpunit ^9.6 || ^10.0 || ^11.0 -> found phpunit/phpunit[9.6.0, ..., 9.6.22, 10.0.0, ..., 10.5.45, 11.0.0, ..., 11.5.7] but it conflicts with your root composer.json require (^12.0).