- Designed and maintained high-availability REST APIs and microservices using AWS services like Lambda, API Gateway, and DynamoDB, optimizing performance and scalability.- Implemented serverless architecture with event-driven design to reduce infrastructure costs and improve API efficiency.-Developed backend services to integrate with ReactJS frontends, enabling seamless data flow and real-time interactions.-Built WebSocket communication systems to support real-time data exchange and reduce latency in high-traffic applications.-Automated CI/CD pipelines with Terraform, AWS CodePipeline, and CodeBuild, enhancing deployment speed across environments.- Collaborated with Agile teams and utilized Test-Driven Development (TDD) methodologies to ensure high code quality and consistency.- Developed and deployed Node.js-based microservices on AWS ECS/EKS, optimizing backend processes for better performance and scalability.- Optimized MongoDB database performance through smart indexing and efficient API routing, enhancing full-stack integration.