Render Argo CD Manifests with helm template, Without CRDs

Original Prepium guide · Written for Kubernetes v1.35 and checked against the official documentation on 6 October 2026. Use a disposable practice cluster. The commands use options present in both Helm 3 and Helm 4, and the example chart is cert-manager from its public repository; nothing below installs it.

Render a pinned Helm chart to a file, and control which CRDs end up in it

A Helm chart is a package of templates plus default values. helm install renders it and creates a tracked release in the cluster; helm template renders the same manifests locally and prints them, creating nothing. Rendering to a file is how you review, diff or hand a chart to another tool. The two details that trip people up are pinning the chart version and understanding that a chart can ship CRDs in two very different ways.

helm repo add NAME URL ──→ local index ──→ helm search repo --versions   (what exists)
                                    ──→ helm show values / show crds     (what is configurable)
                                    ──→ helm template ... --version X > file.yaml   (render only)

1. Add the repository and see what versions exist

helm repo add jetstack https://charts.jetstack.io --force-update
helm repo update
helm search repo jetstack/cert-manager --versions | head

helm repo add stores a name for a URL; the name becomes the prefix in chart references such as jetstack/cert-manager. --versions lists every chart version instead of only the newest. Without --version, later commands use the latest chart, so a render you repeat next month may differ. Note that cert-manager's docs now recommend its OCI registry; the classic repository is used here because it shows the repo add workflow.

2. Learn how this chart ships its CRDs

Helm 3 introduced a special crds/ directory. Files there are not templated: helm install applies them first (and skips them if already present), and --skip-crds turns that step off. helm template leaves them out unless you add --include-crds. Many charts instead put CRDs under templates/ behind a value. Those are ordinary templates, outside the crds/ step that --skip-crds governs, so the chart's value is what removes them. Check which kind you have, using a version from step 1:

helm show crds jetstack/cert-manager --version <chart-version> | head
helm show values jetstack/cert-manager --version <chart-version> | grep -n -A4 '^crds:'

helm show crds prints the chart's CRD files, and helm show values prints its values.yaml. cert-manager's own install docs toggle its CRDs with --set crds.enabled=true, which tells you its CRDs are value-controlled templates. Every chart names this value differently, so always read the values file of the version you pinned.

3. Render to a file with the CRDs left out

kubectl create namespace prepium-tutorial
helm template cm-preview jetstack/cert-manager \
  --version <chart-version> \
  --namespace prepium-tutorial \
  --set crds.enabled=false \
  > /tmp/cm-preview.yaml

The first argument is the release name, which charts typically weave into object names and labels. --namespace sets the release namespace that templates read. cert-manager's docs point out that helm template does not output a Namespace object, so the namespace must exist before you apply the file.

4. Verify the file before trusting it

grep -c '^kind: CustomResourceDefinition' /tmp/cm-preview.yaml     # expect 0
grep -m3 'helm.sh/chart' /tmp/cm-preview.yaml                       # NAME-VERSION, if the chart uses Helm's suggested label
kubectl apply --dry-run=server -f /tmp/cm-preview.yaml | head

The server-side dry run asks the API server to validate every object without saving it, which catches missing namespaces or missing CRDs before a real apply.

Common mistakes

• Relying on --skip-crds for a chart whose CRDs are templates: check the output, and use the chart's own value instead.
• Forgetting --version: the file silently tracks whatever is newest in the index.
• Running helm install when a rendered file was asked for: a release now exists and helm list -A shows it.
• Reading values from the latest chart while rendering an older pinned one: value names can change between versions.

Cleanup: rm /tmp/cm-preview.yaml, kubectl delete namespace prepium-tutorial, helm repo remove jetstack. References: helm template, Helm: Custom Resource Definitions, Helm: Charts, cert-manager Helm install. Next, try Helm for CKAD or Kustomize overlays.