This is a library connecting the excellent Celery task queue with applications written in PHP. Having a proper task queue, as opposed to a bunch of cron jobs and MySQL tables, is essential when your web site performs long-running tasks like encoding video, creating zip files or emailing users.
The library is released under a business-friendly BSD license, is actively maintained and used all around the world. Someone even built an open source Yii Framework extension on top of it.
A simple tool to visually resolve issues with Unix file permissions. Github