Builtin kustomize plugins¶

All standard kustomize transformers and generators are available as KRM functions via karmafun. Use apiVersion: builtin and set kind to the plugin name. The function config fields are identical to the kustomize built-in plugin fields.

Transformers¶

Kind	Description	Docs
`AnnotationsTransformer`	Add / update annotations on resources	↗
`HashTransformer`	Append a content hash to resource names	↗
`ImageTagTransformer`	Update container image tags / digests	↗
`LabelTransformer`	Add / update labels on resources	↗
`NamespaceTransformer`	Set the namespace on all resources	↗
`PatchJson6902Transformer`	Apply RFC 6902 JSON patches	↗
`PatchStrategicMergeTransformer`	Apply strategic merge patches	↗
`PatchTransformer`	Apply JSON 6902 or strategic merge patches	↗
`PrefixTransformer`	Add a prefix to resource names	↗
`SuffixTransformer`	Add a suffix to resource names	↗
`PrefixSuffixTransformer`	Add prefix and suffix in one pass	—
`ReplicaCountTransformer`	Update replica counts	↗
`ValueAddTransformer`	Add a value to a field	↗
`ReplacementTransformer`	Replace field values using sources (extended)	↗
`RemoveTransformer`	Remove resources by selector (custom)	↗
`KCLTransformer`	Transform resources with KCL code (custom)	↗

Generators¶

Kind	Description	Docs
`ConfigMapGenerator`	Generate ConfigMaps from literals / files / envs	↗
`SecretGenerator`	Generate Secrets from literals / files / envs	↗
`HelmChartInflationGenerator`	Render a Helm chart into plain resources	↗
`IAMPolicyGenerator`	Generate IAM policy documents	↗
`GitConfigMapGenerator`	ConfigMap populated with current git repo values (custom)	↗
`KustomizationGenerator`	Generate resources from a kustomization (custom)	↗
`SopsGenerator`	Decrypt SOPS-encrypted files into resources (custom)	↗
`KCLGenerator`	Generate resources from KCL code (custom)	↗

Example: adding labels in-place¶

apiVersion: builtin
kind: LabelTransformer
metadata:
  name: add-labels
  annotations:
    config.karmafun.dev/cleanup: "true"
    config.kubernetes.io/function: |
      exec:
        path: karmafun
labels:
  app.kubernetes.io/managed-by: karmafun
fieldSpecs:
  - path: metadata/labels
    create: true

kustomize fn run --enable-exec --fn-path functions applications