Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires redaxo/php-cs-fixer-config dev-upstream -> satisfiable by redaxo/php-cs-fixer-config[dev-upstream]. - redaxo/php-cs-fixer-config dev-upstream requires friendsofphp/php-cs-fixer ^3.47.1 -> found friendsofphp/php-cs-fixer[v3.47.1, v3.48.0] but it conflicts with your root composer.json require (v3.37.1).