Custom controllers in Kubernetes automate the management of custom resources that are not natively supported by Kubernetes. They are implemented as Kubernetes controllers that watch custom resources and react to changes in their state. Custom resources are created by extending the Kubernetes API with new resource types specific to an organization's needs. Custom controllers can be developed using various programming languages and frameworks, such as the Operator Framework. The Operator Framework provides tools and best practices for developing, testing, and deploying custom controllers.
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