Amazon EventBridge

Event bus service that triggers Lambda and others from events.

Service for building event-driven applications. Routes events from AWS services and custom applications using rules.

• Scheduled execution of daily one-question delivery
• Integration with SaaS events
• Automated processing triggered by state changes

• Used in event-driven architectures
• Also supports scheduled execution
• Plays a different role than SQS or SNS

• Filter target events with event patterns
• Cross-account integration is possible with event buses
• Design retries and DLQs

Amazon EventBridge is a serverless event bus service that aggregates events from AWS services, custom applications, and SaaS partner applications, and routes them to targets (Lambda / Step Functions / SQS / SNS / Kinesis Data Streams / API Gateway / EventBridge in another account, etc.) based on rules. Positioned as the successor of CloudWatch Events, it is characterized by being able to uniformly handle both AWS service integration and SaaS event ingestion. It also supports scheduled execution via schedule expressions (cron / rate expressions) and is widely used as a trigger for scheduled batches and daily deliveries. The core concepts of EventBridge are the three elements of event bus, rules, and targets. Events from AWS services automatically flow into the default event bus, while custom event buses can be used to send application-specific events. Rules narrow down the target events using event patterns (matching conditions in JSON format) and deliver events to up to five targets in parallel. When delivery fails, automatic retries and routing to a DLQ (Dead Letter Queue) are supported, with a retry window of up to 24 hours. Commonly used patterns in practice include monitoring use cases that detect EC2 state changes (start / stop / terminate) and send notifications, CI/CD use cases that detect CodePipeline / CodeBuild state changes and notify Slack or Teams, scheduled execution of daily and weekly batches with EventBridge Scheduler, and integration use cases that ingest events from SaaS (Datadog / PagerDuty / Auth0, etc.) into AWS-side workflows. In the exam context, CLF-C02 asks questions such as "which service is used in event-driven architectures?" and "which service can be used for scheduled execution?". SAA-C03 frequently asks about how to differentiate among SNS / SQS / EventBridge (SNS for pub-sub, SQS for queuing, and EventBridge for event routing).

• Amazon EventBridge (AWS Official)
• What is Amazon EventBridge (AWS Official Documentation)

Last updated: 2026-06-01