Your requirements could not be resolved to an installable set of packages. Problem 1 - pestphp/pest[v2.14.1, ..., 2.x-dev] require phpunit/phpunit ^10.3.2 -> satisfiable by phpunit/phpunit[10.3.2, 10.3.x-dev, 10.4.x-dev (alias of dev-main)]. - pestphp/pest v2.0.1 requires phpunit/phpunit ^10.0.16 -> satisfiable by phpunit/phpunit[10.0.16, ..., 10.4.x-dev (alias of dev-main)]. - pestphp/pest[v2.0.2, ..., v2.2.0] require phpunit/phpunit ^10.0.17 -> satisfiable by phpunit/phpunit[10.0.17, ..., 10.4.x-dev (alias of dev-main)]. - pestphp/pest[v2.2.1, ..., v2.2.3] require phpunit/phpunit ^10.0.18 -> satisfiable by phpunit/phpunit[10.0.18, ..., 10.4.x-dev (alias of dev-main)]. - pestphp/pest[v2.3.0, ..., v2.4.0] require phpunit/phpunit ^10.0.19 -> satisfiable by phpunit/phpunit[10.0.19, ..., 10.4.x-dev (alias of dev-main)]. - pestphp/pest v2.5.0 requires phpunit/phpunit ^10.1.0 -> satisfiable by phpunit/phpunit[10.1.0, ..., 10.4.x-dev (alias of dev-main)]. - pestphp/pest[v2.5.1, ..., v2.5.2] require phpunit/phpunit ^10.1.1 -> satisfiable by phpunit/phpunit[10.1.1, ..., 10.4.x-dev (alias of dev-main)]. - pestphp/pest[v2.5.3, ..., v2.6.0] require phpunit/phpunit ^10.1.2 -> satisfiable by phpunit/phpunit[10.1.2, ..., 10.4.x-dev (alias of dev-main)]. - pestphp/pest v2.6.1 requires phpunit/phpunit ^10.1.3 -> satisfiable by phpunit/phpunit[10.1.3, ..., 10.4.x-dev (alias of dev-main)]. - pestphp/pest v2.6.2 requires phpunit/phpunit ^10.2.0 -> satisfiable by phpunit/phpunit[10.2.0, ..., 10.4.x-dev (alias of dev-main)]. - pestphp/pest v2.6.3 requires phpunit/phpunit ^10.2.1 -> satisfiable by phpunit/phpunit[10.2.1, ..., 10.4.x-dev (alias of dev-main)]. - pestphp/pest[v2.7.0, ..., v2.8.1] require phpunit/phpunit ^10.2.2 -> satisfiable by phpunit/phpunit[10.2.2, ..., 10.4.x-dev (alias of dev-main)]. - pestphp/pest[v2.8.2, ..., v2.9.0] require phpunit/phpunit ^10.2.3 -> satisfiable by phpunit/phpunit[10.2.3, ..., 10.4.x-dev (alias of dev-main)]. - pestphp/pest[v2.9.1, ..., v2.11.0] require phpunit/phpunit ^10.2.6 -> satisfiable by phpunit/phpunit[10.2.6, ..., 10.4.x-dev (alias of dev-main)]. - pestphp/pest v2.12.0 requires phpunit/phpunit ^10.2.7 -> satisfiable by phpunit/phpunit[10.2.7, ..., 10.4.x-dev (alias of dev-main)]. - pestphp/pest[v2.12.1, ..., v2.14.0] require phpunit/phpunit ^10.3.1 -> satisfiable by phpunit/phpunit[10.3.1, 10.3.2, 10.3.x-dev, 10.4.x-dev (alias of dev-main)]. - phpunit/phpunit 10.4.x-dev is an alias of phpunit/phpunit dev-main and thus requires it to be installed too. - phpunit/phpunit[dev-main, 10.0.16, ..., 10.3.2] require ext-xml * -> it is missing from your system. Install or enable PHP's xml extension. - Root composer.json requires pestphp/pest ^2 -> satisfiable by pestphp/pest[v2.0.1, ..., 2.x-dev]. To enable extensions, verify that they are enabled in your .ini files: - /etc/php/8.1/cli/php.ini - /etc/php/8.1/cli/conf.d/20-curl.ini - /etc/php/8.1/cli/conf.d/20-dom.ini - /etc/php/8.1/cli/conf.d/20-mbstring.ini - /etc/php/8.1/cli/conf.d/20-phar.ini - /etc/php/8.1/cli/conf.d/20-simplexml.ini - /etc/php/8.1/cli/conf.d/20-tokenizer.ini - /etc/php/8.1/cli/conf.d/20-xmlwriter.ini - /etc/php/8.1/cli/conf.d/99-pecl.ini You can also run `php --ini` in a terminal to see which files are used by PHP in CLI mode. Alternatively, you can run Composer with `--ignore-platform-req=ext-xml` to temporarily ignore these required extensions.