{"head":{"title":"What Is a Canary Release? Definition and Example | OceanLab","description":"A canary release sends a small share of traffic to a new version first and widens it if all looks well. How it works, an example and the usual mistakes.","canonical":"https://oceanlab.in/glossary/canary-release"},"crumbs":[{"name":"Home","path":"/"},{"name":"Glossary","path":"/glossary"},{"name":"canary release","path":"/glossary/canary-release"}],"slug":"canary-release","term":"Canary release","aka":["canary deployment","progressive rollout"],"category":"Hosting and delivery","short":"A release method that sends a small share of users to a new version first, watches for problems, and widens the rollout step by step.","body":[["The name comes from the canaries miners took underground as an early warning. A canary release might start at one percent of traffic, then five, then twenty-five, then everyone, while error rates and response times are compared with the old version."],["If the numbers get worse, traffic goes back to the old version and only a few users were affected. Canary releases can be done at the router level or in code with a ",{"href":"/glossary/feature-flag","text":"feature flag"},"."]],"why":["Some bugs only show up with real users and real data. A canary limits how many people meet them. It is especially useful for high-traffic products where even a few minutes of a bad release would hurt."],"example":["A payments app ships a new card form to two percent of users. ",{"href":"/glossary/observability","text":"Monitoring"}," shows payment failures for one card brand rising in the canary group, so the rollout stops, the bug is fixed, and the next canary passes cleanly."],"inBuild":["We automate the steps and the checks, so the rollout pauses itself when error rate or latency crosses a threshold. Each step lasts long enough to see normal traffic, and dashboards compare canary and stable side by side."],"mistakes":[["Rolling out faster than the metrics can show a problem."],["No automatic stop, so a bad canary only gets noticed by support tickets."],["Canary groups that are not typical, such as only internal staff."]],"related":[{"href":"/glossary/blue-green-deployment","label":"Blue-green deployment","detail":"A release method that runs two identical production environments and switches all traffic from the old one to the new one in one step."},{"href":"/glossary/feature-flag","label":"Feature flag","detail":"A switch in the code that turns a feature on or off for chosen users at runtime, without deploying new code."},{"href":"/glossary/observability","label":"Observability","detail":"How well you can understand what a running system is doing, and why, from the data it gives off: logs, metrics and traces."},{"href":"/glossary/ci-cd","label":"CI/CD (continuous integration and delivery)","detail":"An automated pipeline that builds and tests every code change (CI) and then releases it to users in a repeatable way (CD)."},{"href":"/glossary/ab-test","label":"A/B test","detail":"An experiment that shows two versions of something to random groups of users and measures which one does better on a chosen metric."}],"tools":[],"links":[{"href":"/pricing/categories/observability","label":"Observability pricing","detail":"Monitoring and tracing prices, with sources."},{"href":"/software","label":"Software by industry","detail":"Systems we build per industry, with guides and tools."}],"sources":[],"legal":false,"updatedAt":"2026-10-25"}