Abstract

Feature flags are pervasive in modern delivery workflows, enabling progressive exposure, rollback, and experimentation without redeployments. In geo-distributed systems, however, eventual consistency across regions can cause flag state drift, yielding non-deterministic behavior and inconsistent user experiences. This paper delves into a protocol and system architecture optimized for feature flag synchronization that balances consistency guarantees with low-latency propagation. A hybrid approach is articulated: strong coordination for critical flags via consensus and low-overhead epidemic dissemination for non-critical flags, coupled with regional caches and version-based reconciliation. An evaluation strategy is presented around propagation latency, staleness bounds, control-plane overhead, and availability impact, with technical considerations for consistency models, fault handling, governance, and security. The treatment is grounded in distributed systems foundations, consensus algorithms, and replicated data maintenance literature, adapted for the specialized control-plane semantics of feature flags.

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