Designing a High-Performance Feature Flag and A/B Testing Frontend System

Designing a High-Performance Feature Flag and A/B Testing Frontend System

Design a frontend architecture and client SDK for a resilient, high-performance Feature Flag and A/B Testing system. Your solution must support both boolean and multivariate flags, dynamic targeting rules, and A/B test bucketing. Address critical frontend challenges such as preventing Flash of Control Content (FOCC)/visual layout shifts, keeping evaluation latency under 2ms, minimizing client-side bundle size, handling offline scenarios, and designing an efficient, deduplicated telemetry buffering system that tracks user exposure events without impacting core thread performance.
ReactTypeScriptEdge MiddlewareMurmurHash3LocalStorageBeacon APISSR
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