Core Serverless Patterns

Serverless patterns matter because a platform is rarely just a function plus a trigger. Real systems are shaped by how requests enter, how events fan out, how scheduled work re-enters safely, and how managed services are composed around short-lived compute. Chapter 4 turns the building blocks from Chapter 2 into reusable architectural patterns instead of isolated service descriptions.

Read the lessons in order. The first covers API-driven serverless as the most common entry pattern. The second moves into event-driven serverless for asynchronous decoupling and elastic fan-out. The third focuses on scheduled and automation patterns where safe re-entry matters more than raw latency. The fourth explains composition with managed services, where functions act as thin control points around storage, messaging, identity, analytics, and workflow systems.

If a design still sounds like a list of cloud products instead of a small number of repeatable architectural shapes, this chapter is the right place to simplify it.

In this section

• API-Driven Serverless
  Explain the common pattern of API gateway plus function handlers plus managed persistence. Show why this is a natural entry point for many teams.
• Event-Driven Serverless
  Describe asynchronous flows triggered by queues, topics, streams, file uploads, or domain events. Explain how this pattern supports decoupling and elasticity.
• Scheduled and Automation Patterns
  Cover cron-like serverless jobs, maintenance tasks, compliance checks, report generation, and infrastructure automation. This section should emphasize reliability and safe re-entry.
• Composition with Managed Services
  Explain the pattern of using serverless functions as orchestration or transformation glue around storage, databases, messaging, identity, analytics, and workflow services.