Unanticipated AWS bill spikes often stem from a lack of daily spending visibility. This technical guide explains how to build an automated FinOps alerting pipeline using AWS Lambda, Boto3, Amazon EventBridge Scheduler, and Amazon S3. Learn how to query the AWS Cost Explorer API, calculate day-over-day cost deltas, and stream structured financial reports directly to Slack channels. #AWS #FinOps #CloudCost #AWSLambda #Boto3 #EventBridge #Slack #DevOps #CloudEngineering #CostOptimization