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content/en/docs/concepts/extend-kubernetes/extend-cluster.md

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 - lavalamp
 - cheftako
 - chenopis
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 Kubernetes is highly configurable and extensible. As a result,
 there is rarely a need to fork or submit patches to the Kubernetes
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 useful as an introduction to what extension points and patterns
 exist, and their trade-offs and limitations.
 
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 ## Overview
 
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 that permits a webhook backend (scheduler extension) to filter and prioritize
 the nodes chosen for a pod.
 
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 * Learn more about [Custom Resources](/docs/concepts/api-extension/custom-resources/)
 * Learn about [Dynamic admission control](/docs/reference/access-authn-authz/extensible-admission-controllers/)
@@ -207,4 +208,4 @@ the nodes chosen for a pod.
 * Learn about [kubectl plugins](/docs/tasks/extend-kubectl/kubectl-plugins/)
 * Learn about the [Operator pattern](/docs/concepts/extend-kubernetes/operator/)
 
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