In shortStart with a canary / Drain gracefully / Watch the right signals / Rollback is a first-class citizen.
1. Start with a canary
One instance gets the new version first. If it clucks happily, we continue.
2. Drain gracefully
Connections finish before an instance is retired. No hen gets pushed off the perch.
3. Watch the right signals
Error rate, latency, and saturation. If any of them drifts, the rollout pauses automatically.
4. Rollback is a first-class citizen
Every deploy keeps the previous version warm for 30 minutes. The way back is always open.
Written by Reginald Crowe, Chief Technology Rooster. Disagree? Tell us. We read every message, usually before the second coffee.