A scalable mass email service was built using AWS services including SES, SQS, Lambda, S3, and CloudWatch to efficiently handle high volumes of emails while ensuring reliability and deliverability. The article provides an overview of the architecture, real-world use cases, pricing predictions, and step-by-step implementation details, along with challenges faced and solutions implemented during the project. Future improvements are suggested, such as adding a user-friendly interface and analytics functionality.

AWS Lambda offers best practices for handling billions of asynchronous invocations, emphasizing the importance of scalability and reliability in serverless applications. The article outlines techniques such as simple queueing, consistent hashing, and shuffle-sharding to mitigate issues like noisy neighbors and traffic spikes, ensuring efficient load distribution and fault tolerance. Additionally, it highlights proactive monitoring and resilience strategies to maintain service quality during high-demand periods.