Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires silverstripe/installer 5.0.0-beta1 -> satisfiable by silverstripe/installer[5.0.0-beta1]. - silverstripe/installer 5.0.0-beta1 requires silverstripe/login-forms ~5.0.0@beta -> satisfiable by silverstripe/login-forms[5.0.0-beta1, 5.0.0-rc1, 5.0.0] from composer repo (https://repo.packagist.org) but silverstripe/login-forms is the root package and cannot be modified. See https://getcomposer.org/dep-on-root for details and assistance.