I heard that Slack is still a monolithic stack built with PHP? Is it true? How's that possible? Are they planning to convert application into microservices in the future? From this quora post, it seems for the backed it's entirely in PHP/Hack built on HHVM. Dude Meta engineers know where to go next https://www.quora.com/What-is-the-tech-stack-behind-Slack #tech #php