Multi-region architecture design
Deploy Meridian across geographic regions with active-active routing, conflict-free replication, and sub-50ms global latency.
1. Region topology
Start with three regions — us-east, eu-west, ap-southeast. Each region runs an independent Meridian node behind a regional load balancer. Use GeoDNS (Route 53 latency-based routing) to steer users to the nearest healthy region.
2. Data plane
Session data stays local to the region. Global state (license keys, user profiles) replicates via CRDT-backed streams over a mesh VPN. Choose DynamoDB Global Tables or CockroachDB for the system of record — both handle cross-region conflict resolution natively.
3. Failover strategy
Health checks run every 5 seconds. If a region fails, DNS automatically withdraws its records. Stale reads are acceptable during the failover window (typically under 30 seconds). Use a circuit breaker at the edge to shed traffic gracefully.
4. Observability
Ship region-scoped traces to a central Honeycomb or Grafana Tempo instance. Tag every span with region and replication_lag_ms. Alert when cross-region replication exceeds 500ms.