Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires friendsofphp/php-cs-fixer ^3.89 -> satisfiable by friendsofphp/php-cs-fixer[v3.89.0, ..., v3.93.1]. - Root composer.json requires phpunit/phpunit ^13.0 -> satisfiable by phpunit/phpunit[13.0.0, 13.0.x-dev, 13.1.x-dev (alias of dev-main)]. - friendsofphp/php-cs-fixer[v3.89.0, ..., v3.89.2] require sebastian/diff ^4.0.6 || ^5.1.1 || ^6.0.2 || ^7.0 -> satisfiable by sebastian/diff[4.0.6, 4.0.x-dev, 5.1.1, 5.1.x-dev, 6.0.2, 6.0.x-dev, 7.0.0, 7.0.x-dev]. - Conclusion: don't install one of sebastian/diff[8.0.0], friendsofphp/php-cs-fixer[v3.93.1] (conflict analysis result) - Conclusion: install sebastian/diff 8.0.0 (conflict analysis result) - You can only install one version of a package, so only one of these can be installed: sebastian/diff[4.0.0, ..., 4.0.x-dev, 5.1.1, 5.1.x-dev, 6.0.2, 6.0.x-dev, 7.0.0, 7.0.x-dev, 8.0.0, 8.0.x-dev].