Implementing a serverless platform on AWS Lambda
BBD has created and implemented a highly scalable, cost-efficient, and fully serverless alerts and notification service on AWS Lambda for a client to inform subscribers about new documents in their central content management system (CMS).
Objectives:
- Build a scalable, lightweight, and automated alerts platform that could notify users when new content matching their subscription filters became available
- Support user-defined schedules for notifications
- Integrate seamlessly with existing CMS and mailing workflows
- Operate with minimal infrastructure overhead and low cost
- Ensure reliability, resilience, and security throughout the process
- Provide automated deployment and version control for rapid iteration and improvements
Benefits:
- Significant reduction in operational overhead by eliminating the need for EC2 instances or containerised workloads
- Highly scalable and cost-efficient system with predictable costs, even as subscriber numbers grew
- Improved time to market for new features through CI/CD automation
- Reliable and seamless integration with the client’s existing CMS, mailing services, and audit / billing systems
- Enhanced governance and compliance through built-in monitoring, retries, and security alerts (CIS and AWS Security Hub)
- Reduced code duplication and simplified maintenance via modular design and the use of Lambda Layers
- Flexible foundation established for expanding into future use cases and communication channels
Overview of the solution:
The client needed a lightweight, automated, and scalable platform to reliably notify users when new documents matching their subscriptions were uploaded to the central CMS. BBD met this need by designing and implementing a fully serverless alerts and notification service using AWS Lambda as the core compute service, triggered on user-defined schedules. The solution also leveraged managed services like Amazon API Gateway, Amazon SQS, and Amazon RDS for orchestration, state management, and data persistence. The implemented system successfully delivered a highly scalable and cost-efficient notification engine that is deeply integrated with the client’s existing workflows and requires minimal infrastructure management.
Approach:
BBD designed the platform around AWS Lambda and Step Functions, ensuring each function adhered to the single responsibility principle for modularity and reusability.
- Orchestration: The layer was built using Amazon API Gateway and Amazon SQS for asynchronous, event-driven execution of Lambda functions
- Data and State Management: Subscriber preferences, workflow state, and failure logs were managed in Amazon RDS for consistency and auditability
- Optimisation: Common dependencies were consolidated into Lambda Layers to optimise performance and reduce duplication across functions
- Development and Deployment: A robust, repeatable development lifecycle was established by integrating the solution with Bitbucket, AWS CDK, and the SAM CLI. CI/CD pipelines were used to automatically build, version, and deploy functions and layers, ensuring rapid feature rollout and operational stability
- Resilience and Cost Control: Operational resilience was achieved through SQS queues handling automatic message retries, and logging failures into RDS. Concurrency limits were intentionally set to avoid unnecessary costs for the batch-process workload. CIS and AWS Security Hub monitoring flagged security misconfigurations
Impact of BBD’s partnership:
BBD delivered a lightweight, cost-efficient, and highly scalable serverless platform that directly addressed the client’s needs for automated subscriber notifications. By leveraging a fully serverless architecture, BBD enabled the client to significantly reduce operational overhead and infrastructure costs associated with containerised or instance-based solutions. The platform’s modular design and CI/CD automation not only accelerated delivery but also simplified ongoing maintenance and change management. Critically, the integration of security and resilience features improved overall platform reliability and compliance, providing business teams with a trustworthy notification mechanism and establishing a flexible foundation for future innovation within the client’s enterprise.