There are many approaches to execute PHP sub-tasks asynchronously or to parallelise PHP execution. While some solutions require extra extensions, individual PHP builds or a lot of process control management, this talk will show you how to configure and use the built-in PHP FastCGI Process Manager (php-fpm) to execute requests asynchronously in an isolated, tunable process pool and eventually handle their responses in a reactive way. Please note that this talk replaces one entitled "Instant Upgrades with Rector" that was due to have been given by Tomas Votruba, who has sent his apologies but is now unable to attend as he has fallen ill. We wish him a speedy recovery.