autoload psr4 is not right.

class Autoload extends \CodeIgniter\Config\AutoloadConfig
{
	public $psr4 = [
		 'Modules' => ROOTPATH.'modules'
	];

        public function __construct()
	{
                print_r($this->psr4);   //here is good
		parent::__construct();
                print_r($this->psr4);  //here is error. no   'Modules' => ROOTPATH.'modules'

[lonnieezell]

That's because the psr4 array gets defined below that, in the constructor. Add your Modules to the existing place in the constructor that's setting psr4 value and it all works just fine.