Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires tempest/validation dev-main -> satisfiable by tempest/validation[dev-main]. - tempest/validation dev-main requires php ^8.4 -> your php version (8.3.14) does not satisfy that requirement. Problem 2 - Root composer.json requires tempest/core dev-main -> satisfiable by tempest/core[dev-main]. - tempest/core dev-main requires php ^8.4 -> your php version (8.3.14) does not satisfy that requirement.