Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires phpunit/phpunit ^12.0 -> satisfiable by phpunit/phpunit[12.0.0]. - phpunit/phpunit 12.0.0 requires php >=8.3 -> your php version (8.1.31) does not satisfy that requirement. Problem 2 - Root composer.json requires laminas/laminas-test ^4.9 -> satisfiable by laminas/laminas-test[4.9.0, ..., 4.11.0]. - laminas/laminas-test[4.9.0, ..., 4.11.0] require phpunit/phpunit ^10.4 -> found phpunit/phpunit[10.4.0, ..., 10.5.45] but it conflicts with your root composer.json require (^12.0).