Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires phpunit/phpunit ^12.0.6 -> satisfiable by phpunit/phpunit[12.0.6]. - phpunit/phpunit 12.0.6 requires php >=8.3 -> your php version (8.2.99; overridden via config.platform, actual: 8.3.17) does not satisfy that requirement. Use the option --with-all-dependencies (-W) to allow upgrades, downgrades and removals for packages currently locked to specific versions.