Using Grab’s Trust Counter Service to Detect Fraud Successfully

This post details the design and implementation of Grab's Counter Service, a self-service platform for fraud detection. It addresses scalability challenges by using ScyllaDB with a multi-buckets strategy for pre-aggregating time-series data into 15min, 1hr, and 1day buckets to improve query performance and meet SLAs. The service offers a UI for counter creation and management, SDKs for backend integration, and a TTL cache layer. It also highlights the role of the Counter Service in ML workflows by providing consistent data sources and counter replay capabilities for historical data simulation.