Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires larastan/larastan ^2.9 -> satisfiable by larastan/larastan[v2.9.0, ..., 2.x-dev]. - Root composer.json requires orchestra/testbench ^6.23 -> satisfiable by orchestra/testbench[v6.23.0, ..., 6.x-dev]. - larastan/larastan[v2.9.9, ..., 2.x-dev] require illuminate/pipeline ^9.52.16 || ^10.28.0 || ^11.16 -> satisfiable by illuminate/pipeline[v9.52.16, 9.x-dev, v10.28.0, ..., 10.x-dev, v11.16.0, ..., 11.x-dev]. - larastan/larastan[v2.9.0, ..., v2.9.8] require illuminate/pipeline ^9.52.16 || ^10.28.0 || ^11.0 -> satisfiable by illuminate/pipeline[v9.52.16, 9.x-dev, v10.28.0, ..., 10.x-dev, v11.0.0, ..., 11.x-dev]. - Conclusion: install laravel/framework 8.x-dev (conflict analysis result) - Only one of these can be installed: illuminate/pipeline[v7.0.0, ..., 7.x-dev, v8.0.0, ..., 8.x-dev, v9.0.0-beta.1, ..., 9.x-dev, v10.0.0, ..., 10.x-dev, v11.0.0, ..., 11.x-dev], laravel/framework[v8.12.0, ..., 8.x-dev]. laravel/framework replaces illuminate/pipeline and thus cannot coexist with it.