Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires lychee-org/phpstan-lychee dev-road-to-phpstan2.0 -> satisfiable by lychee-org/phpstan-lychee[dev-road-to-phpstan2.0]. - lychee-org/phpstan-lychee dev-road-to-phpstan2.0 requires phpstan/phpstan ^2.0 -> satisfiable by phpstan/phpstan[2.0.0, 2.0.1, 2.0.x-dev]. - lychee-org/phpstan-lychee dev-road-to-phpstan2.0 requires symplify/phpstan-rules 12.7.0 -> satisfiable by symplify/phpstan-rules[12.7.0]. - symplify/phpstan-rules 12.7.0 requires phpstan/phpstan ^1.10.30 -> satisfiable by phpstan/phpstan[1.10.30, ..., 1.12.x-dev]. - You can only install one version of a package, so only one of these can be installed: phpstan/phpstan[1.0.0, ..., 1.12.x-dev, 2.0.0, 2.0.1, 2.0.x-dev].