Dragoond is a project mainly written in PHP and SHELL, it's free.
An example of why you don't want to write IRC bots in PHP.
This was a personal assistant I tried writing in the '00s. It's supposed to be PHP with reloadable classes serving as modules.
It was going to be a daemon supporting multiple interfaces (web, IRC, and XMPP) for commands / notifications / etc, but that didn't pan out. PHP can't natively redefine classes and the PECL extension for it (runkit / classkit) was fucking broken and wouldn't reload a class that extended something.
As a result, I did some horrible hack that either didn't work well (memory issue maybe? I don't fucking remember if it even worked at all) and abandoned the project.
Let this serve as a monument to PHP sucking dick.