kubectl kustomize
kubectl kustomize <folder> | kubectl apply -k <folder>
Risk: Safe
What it does
Builds YAML from a base plus an overlay (names, labels, images, replicas).
When to use it
Same app, different settings for dev, staging and prod.
Example
$ kubectl kustomize overlays/prodShow the prod version before applying it.
Learn it in: Kustomize bases and overlays · Official docs