PHP-RBAC is the de-facto authorization library for PHP. It provides NIST Level 2 Standard Hierarchical Role Based Access Control as an easy to use library to PHP developers. It was initially developed in 2008 for use in early versions of jframework, but was matured and ripped later from the jframework to be a stand-alone library.
PHP-RBAC was mostly developed by AbiusX, along with Jesse Burns making contributions towards PSR compliance in PHP-RBAC v2.x. It is now maintained by the same team but is open source and any volunteers would be welcome.
PHP-RBAC is hosted on Github: https://github.com/OWASP/rbac
PHP-RBAC is also an official OWASP project: https://owasp.org/index.php/PHPRBAC