Configure your application. You can load .ini, .json and .yaml files or MySQL DB.
Jasny Config is registred at packagist as jasny/config and can be easily installed using composer.
composer require jasny/config
use Jasny\Config;
$env = getenv('APPLICATION_ENV') ?: 'prod';
$config = new Config('settings.yml');
$config->db = new Config('db.ini');
$config->env = $env;
$config->load("$env.yml", array('optional'=>true)); // Overwrites existing settings