Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires larastan/larastan ^3.1.0 -> satisfiable by larastan/larastan[v3.1.0, 3.x-dev]. - Root composer.json requires laravel/framework 11 -> satisfiable by laravel/framework[v11.0.0]. - larastan/larastan[v3.1.0, ..., 3.x-dev] require illuminate/support ^11.15.0 || ^12.0 -> satisfiable by illuminate/support[v11.15.0, ..., 11.x-dev, 12.x-dev]. - Only one of these can be installed: illuminate/support[v11.0.0, ..., 11.x-dev, 12.x-dev], laravel/framework[v11.0.0]. They all replace spatie/once and thus cannot coexist.