In this chapter, we have examined the futures and tokio crates. The futures crate contains types to work with delayed results and streams. We have compared the Future and Result types and the Stream and Iterator types. After that, we implemented a microservice that stores images and sends them back to the client.

We will improve microservice of this chapter using threads and background tasks in Chapter 10, Background Tasks and Thread Pools in Microservices. But in the next chapter, we will take a look at reactive microservices and using remote procedure calls as an alternative way to implement of microservices.