Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires phpunit/phpunit ^11.4.0 -> satisfiable by phpunit/phpunit[11.4.0]. - Root composer.json requires psalm/plugin-phpunit ^0.19.0 -> satisfiable by psalm/plugin-phpunit[0.19.0]. - phpunit/php-code-coverage 11.0.6 requires nikic/php-parser ^5.1.0 -> satisfiable by nikic/php-parser[v5.1.0, v5.2.0, v5.3.0]. - phpunit/phpunit 11.4.0 requires phpunit/php-code-coverage ^11.0.6 -> satisfiable by phpunit/php-code-coverage[11.0.6]. - psalm/plugin-phpunit 0.19.0 requires vimeo/psalm dev-master || ^5@beta || ^5.0 -> satisfiable by vimeo/psalm[5.25.0, 5.26.0, 5.26.1]. - vimeo/psalm 5.25.0 requires nikic/php-parser ^4.16 -> satisfiable by nikic/php-parser[v4.16.0, ..., v4.19.4]. - vimeo/psalm[5.26.0, ..., 5.26.1] require nikic/php-parser ^4.17 -> satisfiable by nikic/php-parser[v4.17.0, ..., v4.19.4]. - You can only install one version of a package, so only one of these can be installed: nikic/php-parser[v4.16.0, ..., v4.19.4, v5.0.0, ..., v5.3.0].