Amazon API Gateway now integrates with AWS Step Functions, allowing you to call Step Functions with APIs that you create to simplify and customize interfaces to your applications. Step Functions makes it easy to coordinate the components of distributed applications and microservices as a series of steps in a visual workflow. You create state machines in the Step Functions Console or through the Step Functions API to specify and execute the steps of your application at scale. API Gateway is a fully managed service that makes it easy for developers to publish, maintain, monitor, and secure APIs at any scale. With just a few clicks in the AWS Management Console, you can create an API that acts as a “front door” to Step Functions. You can use an API to start Step Functions state machines that coordinate the components of a distributed backend application, such as a web application that tags and resizes uploaded photos, or verifies new users upon registration. You can also integrate human activity tasks in the steps of your application, such as an approval request and response, and make serverless asynchronous calls to APIs of services you use in your application.