Devs Spend 8 Hours Building $0.03/Month

A team of developers has built an automated AWS billing report system using AWS SAM and Microsoft Teams, providing daily visibility into AWS costs across multiple accounts. The system sends daily reports featuring account names, cost analysis, and smart alerts, all for less than $0.50 per month. The solution was necessary due to the increasing difficulty of tracking daily spending as the team's AWS infrastructure grew. The final architecture is simple yet powerful, utilizing AWS Lambda, EventBridge, and Cost Explorer API to process billing data and format reports. The team chose AWS SAM over AWS CDK due to its simplicity and ease of deployment. The system has prevented several cost overruns through early alerts and has become an essential part of the team's FinOps toolkit, with a total development time of approximately 8 hours and a monthly operating cost of around $0.03. The solution has delivered significant value in terms of cost visibility and control, and the team is considering further improvements, including cost anomaly detection and budget integration.