Designing a Reliable File Processing Pipeline on AWS for Real-World Applications

This article presents the design and implementation of a resilient, event-driven file processing pipeline using AWS serverless services (S3, Lambda, SQS, DynamoDB, DLQ) to ensure scalability, fault tolerance, and reliability. The architecture introduces SQS as a buffer between S3 uploads and Lambda processing to absorb traffic spikes, enable safe retries, prevent duplicates via idempotency, and isolate failures with a Dead Letter Queue. The system was validated through real-world testing scenarios including duplicate handling, IAM permission troubleshooting, and controlled failure simulation.