The Symfony PHP framework
Flat-files and plain-old PHP functions rockin'on as a set of general purpose high-level abstractions.
Yii 2: The Fast, Secure and Professional PHP Framework
Slim is a PHP micro framework that helps you quickly write simple yet powerful web applications and APIs.
CakePHP: The Rapid Development Framework for PHP - Official Repository
A PHP framework for web artisans
A powerful yet easy-to-use PHP micro-framework designed to help you build dynamic and robust Web applications - fast!