This is the directory structure of a project:

.
 config     Configuration of the framework
 lib        PHP classes for extensions
 pages      PHP for dynamic pages
 templates  Layouts for dynamic pages
 vendor     External dependencies/libraries
 web        Javascript, CSS, fonts and images

The classes in the lib directory should have the MintyPHP namespace. Public static properties of these classes can be configured from the MintyPHP\Config namespace in the config/config.php file.