No I meant having to do async as opposed to having threads like you would in Java for example. In vast majority of cases a thread pool will work just fine, and it makes your code far simpler. Typically, Java web servers will have a single thread that receives the request and then dispatches it to the pool of workers. The JVM is then responsible for doing the scheduling between the threads and ensuring each one gets to do work. You can do async too, but I've found threads scale to huge loads in practice.