Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires acquia/acquia_cms * -> satisfiable by acquia/acquia_cms[dev-develop]. - acquia/acquia_cms dev-develop requires acquia/acquia-cms-starterkit dev-feature/admin-gin-theme -> found acquia/acquia-cms-starterkit[dev-feature/admin-gin-theme] but it conflicts with your root composer.json require (^1).