Step Functions

It covers the essential workflow patterns you'll actually use: Lambda orchestration, parallel execution, Map state for batch processing, and proper error handling with retries and catches. The source includes working JSON definitions for Choice states, Parallel branches, and Map iterators, plus boto3 examples for creating and executing workflows. What's useful here is the side-by-side comparison of Standard vs Express workflows and a clear breakdown of all eight state types. If you're coordinating multiple AWS services or need durable workflow execution with built-in retry logic, this gives you the patterns to copy and modify.