Your requirements could not be resolved to an installable set of packages. Problem 1 - phpoffice/phpspreadsheet 1.29.0 requires ext-gd * -> it is missing from your system. Install or enable PHP's gd extension. - commongateway/corebundle 1.1.92 requires phpoffice/phpspreadsheet ^1.29 -> satisfiable by phpoffice/phpspreadsheet[1.29.0]. - Root composer.json requires commongateway/corebundle ^1.1.92 -> satisfiable by commongateway/corebundle[1.1.92]. To enable extensions, verify that they are enabled in your .ini files: - /usr/local/etc/php/conf.d/docker-php-ext-exif.ini - /usr/local/etc/php/conf.d/docker-php-ext-mongodb.ini - /usr/local/etc/php/conf.d/docker-php-ext-redis.ini - /usr/local/etc/php/conf.d/docker-php-ext-sodium.ini - /usr/local/etc/php/conf.d/docker-php-ext-zip.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-gd` to temporarily ignore these required extensions.