the point of this kind of thing is that it can allow super fast performance for critical endpoints: Suppose your app consumes a JSON api and it turns out that

the point of this kind of thing is that it can allow super fast performance for critical endpoints: Suppose your app consumes a JSON api and it turns out that one or two endpoints constitute most of the server load. Rewriting one or two endpoints using a lightweight, fast framework can be a great solution, so long as you are already being smart about caching and there aren't other bottlenecks in your architecture.