Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires gammamatrix/playground-test dev-develop|dev-master|dev-feature/*|^73.0 -> satisfiable by gammamatrix/playground-test[dev-develop]. - gammamatrix/playground-test dev-develop requires gammamatrix/playground dev-develop|dev-master|dev-feature/*|^73.0@dev|^73.0 -> found gammamatrix/playground[1.0.0+no-version-set] but it does not match the constraint. See https://getcomposer.org/dep-on-root for details and assistance.