Flagger vs Kanary
Flagger
flagger.appKanary
github.comSide by side
| Figure | Flagger | Kanary |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Self-hosted | Yes | Yes |
| Plans published | 1 | 1 |
| Spec score · Progressive Delivery Software | 8.2 (#11) | 7.4 (#19) |
| License | Flagger is licensed under Apache 2.0. | The repository's license file specifies the MIT License and grants permission to use, copy, modify, distribute, sublicense, and sell copies of the software. |
| Purpose | Flagger automates progressive delivery for applications running on Kubernetes by shifting traffic gradually while measuring metrics and running conformance tests. | Kanary automates canary deployments on Kubernetes through a custom resource definition and controller. |
| Validation | Built-in metric checks can be extended with custom metrics and webhooks for acceptance tests, load tests, or other validation. | Validation options include manual status, label watching, and PromQL queries against Prometheus metrics. |
Plans
In their own words
Flagger
Flagger is a self-hosted Kubernetes operator that automates progressive delivery for applications running on Kubernetes. It gradually shifts traffic to a new version while checking measures such as HTTP or gRPC request success and latency. Deployment approaches include canary releases, A/B testing, and blue/green deployments, routed through an ingress controller or a service mesh compatible with the Kubernetes Gateway API. Built-in checks cover HTTP request success rate and duration; teams can add custom metrics and webhooks for acceptance tests, load tests, or other validation. Release analysis can query systems including Prometheus, Datadog, CloudWatch, New Relic, Graphite, Dynatrace, InfluxDB, and Google Cloud Monitoring. If SLO analysis detects a performance drop, Flagger rolls back the release automatically. Manual controls allow approval, pausing, or resuming deployments, and notifications can go to Slack, Microsoft Teams, Discord, or Rocket. It is configured through Kubernetes custom resources, works with Kubernetes-compatible CI/CD solutions, and can be used with Flux for GitOps canary pipelines. Flagger is Apache 2.0 licensed and free.