Flat-files and plain-old PHP functions rockin'on as a set of general purpose high-level abstractions.
SilverStripe Framework, the MVC framework that powers SilverStripe CMS
The Symfony PHP framework
[READ-ONLY] Flow Application Framework, provides MVC, DI, AOP, Security, …
The HttpKernel component provides a structured process for converting a Request into a Response.
HttpKernel adapter for use of Symfony and Laravel frameworks with PHP-PM
Someline Starter is a PHP framework for quick building Web Apps and Restful APIs, with modern PHP design pattern foundation.
CakePHP: The Rapid Development Framework for PHP - Official Repository
Slim is a PHP micro framework that helps you quickly write simple yet powerful web applications and APIs.