FluxCD

# --path is the dir with the app's kustomization.yaml.
# --kustomization-file is the dir containing the FLUX kustomization object/file.

flux build kustomization my-app \
  --path path/to/my-app \
  --kustomization-file path/to/flux-kustomization.yaml \
  --dry-run

# single line
flux build kustomization my-app --path path/to/my-app --kustomization-file path/to/flux-kustomization.yaml --dry-run