`kustomize` - template-free customization of Kubernetes YAML (v5.7)

kustomize build DIR | kustomize edit set image|namespace|replicas ... | kustomize edit add resource F

Options you will use

build DIR: Render a kustomization (same as kubectl kustomize DIR).
edit set image NAME=NEWNAME:TAG | NAME:TAG | NAME@DIGEST: Set the images: entry in ./kustomization.yaml - the one-line change a GitOps pipeline commits.
edit set namespace NS / edit set replicas NAME=N / edit add resource FILE: Other edits of ./kustomization.yaml.

Examples

$ cd overlays/dev && kustomize edit set image registry.lab/pay/payments-api@sha256:...

Pin dev to the digest CI pushed.

Gotchas

configMapGenerator/secretGenerator names get a content hash; references are rewritten, so a config change rolls the pods.
edit rewrites the file in kustomize's own format (comments are lost).

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