Streamline Serverless Apps with AWS Lambda and EventBridge
Learn to build event-driven serverless apps with AWS Lambda and EventBridge. Automate workflows, send real-time notifications, and streamline operations.
Published Jan 27, 2025
Modern application development thrives on the principles of scalability, flexibility, and minimal operational overhead. Enter serverless computing—a paradigm shift that lets developers focus solely on code without worrying about infrastructure. In this guide, we explore how AWS Lambda and Amazon EventBridge work in tandem to build powerful, event-driven applications. We’ll also walk through a practical example, complete with an architecture diagram and implementation tips.
AWS Lambda enables you to run code without provisioning or managing servers. It automatically scales based on demand and integrates seamlessly with AWS services. Amazon EventBridge, on the other hand, acts as a central hub for event routing, connecting applications with data from AWS services, third-party SaaS providers, and custom applications.
Together, they form the backbone of event-driven architectures that:
- React to changes in real-time.
- Simplify integration between microservices.
- Enable automation of workflows.
- Reduce operational complexity.
Imagine an e-commerce application that sends notifications to customers whenever their order status changes. We’ll build a serverless solution using AWS Lambda and Amazon EventBridge to achieve this.

Diagram Description: A flowchart showing the following:
- An "Order Management System" emitting events to an Amazon EventBridge event bus.
- EventBridge applying rules to route "Order Status Change" events to an AWS Lambda function.
- The Lambda function processing the event and sending a notification via Amazon SNS (Simple Notification Service).
The first step is configuring your order management system to publish events to an EventBridge event bus. Each event should include key details like
orderId
, customerId
, and status
(e.g., "Shipped," "Delivered").Create an EventBridge rule to filter "Order Status Change" events. Use a pattern like this:
The rule targets the AWS Lambda function that will process the event.
Write a Lambda function to process the event and send a notification. Here’s an example in Python:
- Publish a test event to your EventBridge bus:
aws events put-events --entries file://test-event.json
- Check if the Lambda function processes the event and publishes a message to the SNS topic.
- Optimize EventBridge Rules: Minimize unnecessary invocations by filtering events effectively.
- Use Dead Letter Queues (DLQs): Configure DLQs for Lambda to capture unprocessed events.
- Implement Idempotency: Ensure your Lambda function handles duplicate events gracefully.
- Monitor with CloudWatch: Set up alarms and dashboards to track performance and error rates.
AWS Lambda and Amazon EventBridge simplify the development of event-driven architectures, allowing you to automate workflows and react to events in real time. By combining these services, you can reduce operational overhead and focus on delivering value to your customers.