Recipe
Blue-Green Deploys
Zero-downtime deployments with instant rollback capability.
Overview
Blue-green deployment runs two identical production environments — blue (current live) and green (new version). Traffic flips atomically via a load-balancer switch. If the green environment fails, revert to blue in seconds.
Why Meridian Uses It
- Zero user-facing downtime during releases
- Full production smoke-testing before cutover
- Instant rollback — no rebuild, no redeploy
- Eliminates deployment anxiety for the team
How We Execute
- Provision green environment (identical to blue — compute, DB replica, config)
- Deploy new build to green, run migration against replica
- Smoke-test green: health checks, critical-path API calls, DB connectivity
- Flip load-balancer target from blue → green
- Monitor green for 5 minutes; if stable, decommission blue
- If anomalies detected, flip back to blue immediately
Pro Tip
Keep the previous blue environment warm for at least one full traffic cycle before tearing it down. Transient issues (cold caches, DNS propagation) can surface minutes after cutover.