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Adding a new chart

First: do you need a new chart?

  • If the service fits the generic shape (deployment/statefulset, service, ingress, config, secrets — anything expressible as Kubernetes objects), use app-chart with a values file. Don't add a chart.
  • Only add a dedicated chart when a service has real chart logic the generic chart can't express — a CRD, an operator, complex conditional wiring. A new chart that just re-implements app-chart is a maintenance trap.

Skeleton

Create one folder under charts/, same shape as app-chart:

charts/<name>/
├── Chart.yaml            # apiVersion: v2, name: <name>, version: 0.1.0
├── values.yaml           # documented (# -- comments feed the README)
├── README.md.gotmpl      # helm-docs template (README.md is generated)
├── .helmignore           # exclude tests/, ci/, *.gotmpl from the package
├── templates/            # your templates
├── tests/                # helm-unittest suites (required)
└── ci/
    └── example-values.yaml   # realistic values for lint / kubeconform / Trivy

Steps

  1. Chart.yaml — apiVersion: v2, a unique name, version: 0.1.0, type: application, and a maintainers entry.
  2. values.yaml — start empty/off-by-default; document each key with a # -- comment (helm-docs turns these into the README table) and add a short commented example after each.
  3. templates/ — write the templates. Keep secrets out of the chart; use ExternalSecrets or values.
  4. tests/ — add helm-unittest suites asserting the rendered output. This is required: it's what locks behavior. Run make unittest.
  5. ci/example-values.yaml — a realistic values file. ct lint, kubeconform, and Trivy all render the chart with it, so make it clean (resources set, hardened securityContext, no HIGH/CRITICAL Trivy findings).
  6. README.md.gotmpl + .helmignore — copy app-chart's, then run make docs to generate README.md. Never hand-edit the generated README.
  7. (Optional) CODEOWNERS — add a /charts/<name>/ @team line if a specific team owns it.

What you get for free

CI discovers the new chart automatically — no workflow edits:

  • ct lint (via ct list-changed) lints it on PRs that touch it.
  • helm-unittest runs its tests/.
  • kubeconform validates its ci/ render.
  • Trivy scans its ci/ render for misconfig + secrets.
  • On merge to main, chart-releaser publishes it once version is set.

Verify locally before opening a PR

make unittest
make lint
make kubeconform
make pre-commit

See chart-publishing.md for how the chart then gets versioned and published.