Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires phpunit/phpunit ^13.3.1 -> satisfiable by phpunit/phpunit[13.3.1, 13.3.x-dev, 13.4.x-dev]. - phpunit/phpunit[13.3.1, ..., 13.4.x-dev] require php >=8.4.1 -> your php version (8.0.30) 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.