Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires php ^8.2 but your php version (8.1.27) does not satisfy that requirement. Problem 2 - Root composer.json requires phpunit/phpunit ^11.0 -> satisfiable by phpunit/phpunit[11.0.0, ..., 11.0.8]. - phpunit/phpunit[11.0.0, ..., 11.0.8] require php >=8.2 -> your php version (8.1.27) does not satisfy that requirement.