What is a Canary Deployment?

Updated Apr 28, 2026

Short answer

A release strategy where a new version is rolled out to a small subset of users before deploying it to the entire infrastructure.

Deep explanation

It acts as an early warning system. Traffic is routed to the canary (e.g., 5%). If monitoring shows increased error rates or latency, the deployment is automatically rolled back. If successful, traffic is gradually increased to 100%.

Real-world example

Routing 2% of live traffic to a new microservice version to verify it doesn't crash under real-world data payloads before replacing the old version.

Common mistakes

  • Confusing Canary with A/B testing. A/B testing is for measuring user behavior/business metrics
  • Canary is for measuring technical stability.

Follow-up questions

  • How is routing handled in Canary deployments?

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