Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires illuminate/support ^10 -> satisfiable by illuminate/support[v10.0.0, ..., v10.48.22]. - Root composer.json requires larastan/larastan ^2.9 -> satisfiable by larastan/larastan[v2.9.0, ..., v2.9.9]. - Root composer.json requires orchestra/testbench ^9.5 -> satisfiable by orchestra/testbench[v9.5.0, v9.5.1, v9.5.2]. - larastan/larastan[v2.9.0, ..., v2.9.8] require illuminate/support ^9.52.16 || ^10.28.0 || ^11.0 -> satisfiable by illuminate/support[v10.28.0, ..., v10.48.22], laravel/framework[v11.11.0, ..., v11.28.1]. - larastan/larastan v2.9.9 requires illuminate/support ^9.52.16 || ^10.28.0 || ^11.16 -> satisfiable by illuminate/support[v10.28.0, ..., v10.48.22], laravel/framework[v11.16.0, ..., v11.28.1]. - Conclusion: don't install illuminate/support v10.48.22 (conflict analysis result) - Only one of these can be installed: laravel/framework[v11.11.0, ..., v11.28.1], illuminate/support[v10.0.0, ..., v10.48.22]. laravel/framework replaces illuminate/support and thus cannot coexist with it.