Packages

Package	Namespace	Tasks
sylius-starter/core	SyliusStarter\Core	Castor plugin: SyliusService, installer, sylius:fixtures, helpers
sylius-starter/plugins	SyliusStarter\Plugins	sylius:plugin:add, sylius:plugin:remove
sylius-starter/themes	SyliusStarter\Themes	sylius:theme:setup
sylius-starter/menu	SyliusStarter\Menu	sylius:menu:remove
sylius-starter/datasets	SyliusStarter\Datasets	ready-made datasets for sylius:import:shop:create
sylius-starter/import	SyliusStarter\Import	sylius:import:*
sylius-starter/upsun	SyliusStarter\Upsun	sylius:upsun:*
sylius-starter/sylius-starter	—	All of the above

The core is the Castor plugin itself. Every other package only contributes tasks: it registers them in the core from a file autoloaded by Composer, so installing a package is enough to get its tasks on your SyliusService.