php debug tools

https://xdebug.org/download.php

https://github.com/raveren/kint/releases

https://code.google.com/archive/p/webgrind/

https://filp.github.io/whoops/

https://github.com/filp/whoops/tags

http://www.phpgang.com/create-a-web-service-with-php_43.html

http://www.phpgang.com/12-reasons-to-choose-php-for-developing-website-in-2016_3191.html

http://www.phpgang.com/best-debugging-tools-in-php_3425.html