What is a canary release, and how does it reduce the blast radius of a risky Node.js deployment?

A canary release routes a small percentage of traffic to a new version while the majority hits the stable version -- key metrics are monitored closely, and traffic is gradually shifted further if healthy, or rolled back immediately if problems appear, limiting exposure to a small user subset.

http:
  route:
  - destination: { host: myapp, subset: stable }
    weight: 95
  - destination: { host: myapp, subset: canary }
    weight: 5