Once a workflow spans retries, waits, branching, parallel work, or human input, the system needs explicit coordination instead of improvised control flow hidden inside handlers.
This chapter covers the point where serverless systems stop being single-function utilities and start behaving like real business processes. Once a workflow spans retries, waits, branching, parallel work, or human input, the system needs explicit coordination instead of improvised control flow hidden inside handlers.
Read the lessons in order. They move from managed workflow engines to parallel fan-out and fan-in patterns, then to long-running process design, and finally to saga and compensation thinking. The common thread is that durable coordination should live in explicit workflow state, not in function memory or nested callback logic.