kustomize
https://kustomize.io/
Kustomize introduces a template-free way to customize application configuration that simplifies the use of off-the-shelf applications. Now, built into kubectl as apply -k.
https://kubernetes.io/docs/tasks/manage-kubernetes-objects/kustomization/
Kustomize is a standalone tool to customize Kubernetes objects through a kustomization file.
Kubernetes オブジェクトを変更する独立したツール
kustomization ファイルを利用する