Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires PHP extension ext-parallel * but it is missing from your system. Install or enable PHP's parallel extension. Problem 2 - Root composer.json requires react-parallel/event-loop dev-master as 2.0 -> satisfiable by react-parallel/event-loop[dev-master]. - react-parallel/event-loop dev-master requires ext-parallel * -> it is missing from your system. Install or enable PHP's parallel extension. Problem 3 - Root composer.json requires react-parallel/runtime dev-master as 3.0 -> satisfiable by react-parallel/runtime[dev-master]. - react-parallel/runtime dev-master requires ext-parallel * -> it is missing from your system. Install or enable PHP's parallel extension. Problem 4 - Root composer.json requires react-parallel/pool-tests dev-PHP-8.2-PLUS as 4.0 -> satisfiable by react-parallel/pool-tests[dev-PHP-8.2-PLUS]. - react-parallel/pool-tests dev-PHP-8.2-PLUS requires ext-parallel * -> it is missing from your system. Install or enable PHP's parallel extension. To enable extensions, verify that they are enabled in your .ini files: - /usr/local/etc/php/8.2/php.ini - /usr/local/etc/php/8.2/conf.d/20-ds.ini - /usr/local/etc/php/8.2/conf.d/20-pcov.ini - /usr/local/etc/php/8.2/conf.d/ext-opcache.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-parallel` to temporarily ignore these required extensions. Use the option --with-all-dependencies (-W) to allow upgrades, downgrades and removals for packages currently locked to specific versions.