Helm Chart Builder

Helm Chart Builder

Production-grade Helm charts. Sensible defaults. Secure by design. No cargo-culting.

Opinionated Helm workflow that turns ad-hoc Kubernetes manifests into maintainable, testable, reusable charts. Covers chart structure, values design, template patterns, dependency management, and security hardening.

Not a Helm tutorial — a set of concrete decisions about how to build charts that operators trust and developers don't fight.

Slash Commands

When This Skill Activates

Recognize these patterns from the user:

• "Create a Helm chart for this service"
• "Review my Helm chart"
• "Is this chart secure?"
• "Design a values.yaml"
• "Add a subchart dependency"
• "Set up helm tests"
• "Helm best practices for [workload type]"
• Any request involving: Helm chart, values.yaml, Chart.yaml, templates, helpers, _helpers.tpl, subcharts, helm lint, helm test

If the user has a Helm chart or wants to package Kubernetes resources → this skill applies.

Workflow

/helm:create — Chart Scaffolding

1. Identify workload type

   • Web service (Deployment + Service + Ingress)
   • Worker (Deployment, no Service)
   • CronJob (CronJob + ServiceAccount)
   • Stateful service (StatefulSet + PVC + Headless Service)
   • Library chart (no templates, only helpers)

2. Scaffold chart structure

   mychart/
   ├── Chart.yaml              # Chart metadata and dependencies
   ├── values.yaml             # Default configuration
   ├── values.schema.json      # Optional: JSON Schema for values validation
   ├── .helmignore             # Files to exclude from packaging
   ├── templates/
   │   ├── _helpers.tpl        # Named templates and helper functions
   │   ├── deployment.yaml     # Workload resource
   │   ├── service.yaml        # Service exposure
   │   ├── ingress.yaml        # Ingress (if applicable)
   │   ├── serviceaccount.yaml # ServiceAccount
   │   ├── hpa.yaml            # HorizontalPodAutoscaler
   │   ├── pdb.yaml            # PodDisruptionBudget
   │   ├── networkpolicy.yaml  # NetworkPolicy
   │   ├── configmap.yaml      # ConfigMap (if needed)
   │   ├── secret.yaml         # Secret (if needed)
   │   ├── NOTES.txt           # Post-install usage instructions
   │   └── tests/
   │       └── test-connection.yaml
   └── charts/                 # Subcharts (dependencies)

3. Apply Chart.yaml best practices

   METADATA
   ├── apiVersion: v2 (Helm 3 only — never v1)
   ├── name: matches directory name exactly
   ├── version: semver (chart version, not app version)
   ├── appVersion: application version string
   ├── description: one-line summary of what the chart deploys
   └── type: application (or library for shared helpers)
   
   DEPENDENCIES
   ├── Pin dependency versions with ~X.Y.Z (patch-level float)
   ├── Use condition field to make subcharts optional
   ├── Use alias for multiple instances of same subchart
   └── Run helm dependency update after changes

4. Generate values.yaml with documentation

   • Every value has an inline comment explaining purpose and type
   • Sensible defaults that work for development
   • Override-friendly structure (flat where possible, nested only when logical)
   • No hardcoded cluster-specific values (image registry, domain, storage class)

5. Validate

   python3 scripts/chart_analyzer.py mychart/
   helm lint mychart/
   helm template mychart/ --debug

/helm:review — Chart Analysis

1. Check chart structure

   Check	Severity	Fix
   Missing _helpers.tpl	High	Create helpers for common labels and selectors
   No NOTES.txt	Medium	Add post-install instructions
   No .helmignore	Low	Create one to exclude .git, CI files, tests
   Missing Chart.yaml fields	Medium	Add description, appVersion, maintainers
   Hardcoded values in templates	High	Extract to values.yaml with defaults

2. Check template quality

   Check	Severity	Fix
   Missing standard labels	High	Use app.kubernetes.io/* labels via _helpers.tpl
   No resource requests/limits	Critical	Add resources section with defaults in values.yaml
   Hardcoded image tag	High	Use {{ .Values.image.repository }}:{{ .Values.image.tag }}
   No imagePullPolicy	Medium	Default to IfNotPresent, overridable
   Missing liveness/readiness probes	High	Add probes with configurable paths and ports
   No pod anti-affinity	Medium	Add preferred anti-affinity for HA
   Duplicate template code	Medium	Extract into named templates in _helpers.tpl

3. Check values.yaml quality

   python3 scripts/values_validator.py mychart/values.yaml

4. Generate review report

   HELM CHART REVIEW — [chart name]
   Date: [timestamp]
   
   CRITICAL: [count]
   HIGH:     [count]
   MEDIUM:   [count]
   LOW:      [count]
   
   [Detailed findings with fix recommendations]