Sequential consistency without borders: how D1 implements global read replication

Cloudflare announces public beta support for D1 read replication, enabling read-only replicas across regions to reduce latency and increase throughput while maintaining sequential consistency via a new Sessions API and bookmark mechanism. The post explains how sessions ensure read-after-write correctness across replicas, outlines how to enable the feature, describes operational metadata returned by queries, and details the underlying architecture leveraging SQLite WAL, Durable Objects, and Storage Relay Service for low-lag replication and transparent routing of reads and write forwarding to primaries.