Service meshes and API gateways provide a convenient way to route traffic to a variety of microservices, all of which implement the same API interface. Flagger uses this feature to dynamically adjust the portion of traffic that is routed to a new version of a service. This is a common technique for canary releases or blue/green deployment. Flagger works in conjunction with a variety of popular proxies (including Envoy and Kong) to progressively ramp up requests to a service and report metrics on the load in order to provide fast feedback on a new release. We like that Flagger simplifies this valuable practice so that it can be more widely adopted. Although Flagger is sponsored by Weaveworks, it stands on its own with no obligation to use it in conjunction with Weaveworks' other tooling.