Lease Coordination Under Serializable Isolation in CockroachDB

Multi-region systems that rely on entity-scoped write coordination often reach a scale where correctness is no longer the primary challenge; predictability under sustained concurrency is. CockroachDB’s serializable isolation model makes lease-based coordination attractive because it eliminates external lock services while preserving strict ordering guarantees. Early architecture reviews typically focus on invariants: single-writer enforcement, fencing epochs, failover safety, and replication durability.