SQS Lambda Worker Pattern
CloudFormation: SQS queue with Lambda consumer, configurable batch size, DLQ for failures, and CloudWatch alarms on queue depth and DLQ message count.
SQS Lambda Worker Pattern
The reliable message processing pattern, correctly implemented. SQS queue, Lambda consumer with proper partial batch failure handling, DLQ, and CloudWatch alarms — all wired in one CloudFormation stack.
What's Included
- SQS queue with configurable visibility timeout and message retention
- Lambda consumer (Node.js 22) with SQS event source mapping
- Configurable BatchSize and MaximumBatchingWindowInSeconds parameters
- DLQ for messages that exhaust all retries
- CloudWatch alarm on main queue depth and DLQ depth
- IAM role with SQS and CloudWatch permissions
Developer Experience
The Lambda handler demonstrates correct batchItemFailures partial batch failure handling — the most misunderstood part of SQS/Lambda integration. Process records independently, return only failed message IDs, and SQS retries just those.
What You Get
A solid worker foundation for any async workload. Includes a send-test-message.sh script to verify your consumer after deploy.
Requirements
AWS CLI v2 with CloudFormation, SQS, Lambda, IAM, and CloudWatch permissions.