Leela Kumili writes that Cursor has introduced Continuity, a novel Git storage architecture designed for massive scale by utilizing an Amazon S3-backed write-ahead log (WAL) as the primary source of truth. By moving the consistency boundary from individual replica coordination to durable object storage, Cursor can support high throughput and large numbers of replicas, achieving over 300 pushes per second when using S3 Express One Zone. This architecture specifically addresses the needs of massive monorepos used in CI workloads and the surge in small repositories generated by autonomous coding agents.
- Local NVMe repositories function as warm caches rather than authoritative copies.
- Rendezvous hashing is utilized to select preferred nodes for data access.
- UDP gossip protocols propagate WAL updates across the system.
- High performance is achieved via batching operations to mitigate S3 PUT latency.
- Local NVMe repositories function as warm caches rather than authoritative copies.
- Rendezvous hashing is utilized to select preferred nodes for data access.
- UDP gossip protocols propagate WAL updates across the system.
- High performance is achieved via batching operations to mitigate S3 PUT latency.
