PHP Debugbar integration for Laravel
Common additional features for Twig that do not directly belong in core
Kint - debugging helper for PHP developers
Debug bar in the browser for php application
Tracy: useful PHP debugger
Symfony mechanism for exploring and dumping PHP variables
Webgrind is a Xdebug profiling web frontend in PHP5. It implements a subset of the features of kcachegrind and installs in seconds and works on all platforms. For quick'n'dirty optimizations it does the job.
CakePHP Debug Kit
PHP library for Google Chrome extension "PHP Console".
The debugger extension for the Yii framework
Module for developer and debug tools for use with zend-mvc applications.
The Drupal CLI. A tool to generate boilerplate code, interact with and debug Drupal.
Symfony Debug Component
PHP 5.3+ micro logging class that can be extended via closures. Includes several pre-built handlers including file, mail, syslog, HTTP post, and MongoDB.
Shows you caching information around ESI requests for debugging purposes
A configurable set of panels that display various debug information about the current request/response.
Memcache Doctrine caching and session storage in the Web Debug Toolbar
Symfony 2 console command to debug listeners
Adds useful Git information to the Symfony2 Debug Toolbar
A handsome replacement for print_r & var_dump. Debugging output with understated style.
User friendly Exception and Error handler ported from Nette Framework.
This component provides a set of classes that help you to debug an application. It provides timers and report generators for different formats that give a summary of warnings and errors that occurred within your application.
a cleaner, leaner mix of print_r() and var_dump()
A nicer print_r/var_dump alternative for PHP 5.3+
Most beautiful variable dump library for PHP (ColdFusion like style)