One way of maintaining the state of our application is to continuously exchange messages between all services that need to be informed of state changes. But when working with technologies that allow us to design applications that are serverless, we might find it difficult to coordinate the message relaying between all of the components. Also, manual tasks in our business process might be difficult to implement through messaging alone. We need a tool to enable the simple coordination of automated and manual activities that map to our business process, and the Simple Workflow Service (SWF) provides just that capability.

The following topics will be covered in this chapter:

• Introduction to SWF
• Components of SWF
• Managing access with IAM