Reliable and Scalable Feature Toggles and A/B Testing SDK at Grab

This post details the evolution of Grab's feature toggling and A/B testing platform. It introduces a new SDK designed for sub-microsecond decisions, eliminating network calls for feature toggle retrieval by fetching configurations from S3 and constructing in-memory models. The SDK supports dynamic configurations (rollouts) with JSON-based definitions and experiments with advanced features like time-sliced shuffling. It also introduces the concept of 'facets' for contextual decision-making and tracking, and a Track() method for event logging directly to the data lake.