The documentation on middleware just says "You can write your own middleware." and has an example that is entirely unexplained. This really needs real documentation. What order are they called in? Does next have any parameters? Would definitely be worth spelling out that "the middelware function is called for every matching endpoint before the request handler is run and calling 'await next()' will wait for the response to be sent before being run" (or whatever is actually the case). As it stands, way too much has to be assumed or inferred by this.