What are serverless architecture patterns?

Serverless architecture patterns are approaches to building applications where developers focus on writing code without managing servers. These patterns rely on cloud providers to handle infrastructure, scaling, and maintenance. Common serverless patterns include event-driven processing, API Gateway-backed HTTP services, and orchestrated workflows. Each pattern addresses specific use cases by abstracting infrastructure concerns, allowing developers to deploy code in response to events, HTTP requests, or scheduled tasks. Serverless doesn’t eliminate servers but shifts operational responsibilities to the cloud provider, enabling faster development cycles.

One key pattern is the event-driven architecture, where functions execute in response to events like file uploads, database changes, or messages in a queue. For example, AWS Lambda can trigger when a file is uploaded to Amazon S3, process the file, and store results in a database. Another pattern is the API Gateway integration, which routes HTTP requests to serverless functions. This is often used for building REST APIs—a frontend app might send a request to an API Gateway, which invokes a Lambda function to fetch data from DynamoDB. A third pattern is orchestration with services like AWS Step Functions, which coordinate multiple serverless functions into a workflow. For instance, an e-commerce order processing system might use Step Functions to chain functions for payment validation, inventory checks, and shipping notifications.

Serverless patterns are best suited for sporadic or unpredictable workloads, microservices, and tasks requiring automatic scaling. Benefits include reduced operational overhead, pay-per-use pricing, and built-in fault tolerance. However, they may not be ideal for long-running processes or applications with strict latency requirements. For example, a serverless API can scale instantly during traffic spikes without manual intervention, but a high-performance gaming backend might need dedicated servers. By combining these patterns—like using API Gateway for frontend interactions, event-driven functions for background tasks, and orchestration for complex logic—developers can build scalable, cost-effective systems without infrastructure management.