Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires phpunit/phpunit ^11.1.0 -> satisfiable by phpunit/phpunit[11.1.0, 11.1.x-dev, 11.2.x-dev]. - phpunit/phpunit[11.1.0, ..., 11.2.x-dev] require php >=8.2 -> your php version (8.1.27) 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.