alirezarezvani/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.

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Slash Commands

| Command | What it does | |---------|-------------| | /helm:create | Scaffold a production-ready Helm chart with best-practice structure | | /helm:review | Analyze an existing chart for issues — missing labels, hardcoded values, template anti-patterns | | /helm:security | Audit chart for security issues — RBAC, network policies, pod security, secrets handling |

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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.

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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]
   

/helm:security — Security Audit

1. Pod security audit

   | Check | Severity | Fix | |-------|----------|-----| | No securityContext | Critical | Add runAsNonRoot, readOnlyRootFilesystem | | Running as root | Critical | Set runAsNonRoot: true, runAsUser: 1000 | | Writable root filesystem | High | Set readOnlyRootFilesystem: true + emptyDir for tmp | | All capabilities retained | High | Drop ALL, add only specific needed caps | | Privileged container | Critical | Set privileged: false, use specific capabilities | | No seccomp profile | Medium | Set seccompProfile.type: RuntimeDefault | | allowPrivilegeEscalation true | High | Set allowPrivilegeEscalation: false |

2. RBAC audit

   | Check | Severity | Fix | |-------|----------|-----| | No ServiceAccount | Medium | Create dedicated SA, don't use default | | automountServiceAccountToken true | Medium | Set to false unless pod needs K8s API access | | ClusterRole instead of Role | Medium | Use namespace-scoped Role unless cluster-wide needed | | Wildcard permissions | Critical | Use specific resource names and verbs | | No RBAC at all | Low | Acceptable if pod doesn't need K8s API access |

3. Network and secrets audit

   | Check | Severity | Fix | |-------|----------|-----| | No NetworkPolicy | Medium | Add default-deny ingress + explicit allow rules | | Secrets in values.yaml | Critical | Use external secrets operator or sealed-secrets | | No PodDisruptionBudget | Medium | Add PDB with minAvailable for HA workloads | | hostNetwork: true | High | Remove unless absolutely required (e.g., CNI plugin) | | hostPID or hostIPC | Critical | Never use in application charts |

4. Generate security report

   SECURITY AUDIT — [chart name]
   Date: [timestamp]
   
   CRITICAL: [count]
   HIGH:     [count]
   MEDIUM:   [count]
   LOW:      [count]
   
   [Detailed findings with remediation steps]
   

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Tooling

scripts/chart_analyzer.py

CLI utility for static analysis of Helm chart directories.

Features:

• Chart structure validation (required files, directory layout)
• Template anti-pattern detection (hardcoded values, missing labels, no resource limits)
• Chart.yaml metadata checks
• Standard labels verification (app.kubernetes.io/*)
• Security baseline checks
• JSON and text output

Usage:

# Analyze a chart directory
python3 scripts/chart_analyzer.py mychart/

# JSON output
python3 scripts/chart_analyzer.py mychart/ --output json

# Security-focused analysis
python3 scripts/chart_analyzer.py mychart/ --security

scripts/values_validator.py

CLI utility for validating values.yaml against best practices.

Features:

• Documentation coverage (inline comments)
• Type consistency checks
• Hardcoded secrets detection
• Default value quality analysis
• Structure depth analysis
• Naming convention validation
• JSON and text output

Usage:

# Validate values.yaml
python3 scripts/values_validator.py values.yaml

# JSON output
python3 scripts/values_validator.py values.yaml --output json

# Strict mode (fail on warnings)
python3 scripts/values_validator.py values.yaml --strict

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Template Patterns

Pattern 1: Standard Labels (_helpers.tpl)

{{/*
Common labels for all resources.
*/}}
{{- define "mychart.labels" -}}
helm.sh/chart: {{ include "mychart.chart" . }}
app.kubernetes.io/name: {{ include "mychart.name" . }}
app.kubernetes.io/instance: {{ .Release.Name }}
app.kubernetes.io/version: {{ .Chart.AppVersion | quote }}
app.kubernetes.io/managed-by: {{ .Release.Service }}
{{- end }}

{{/*
Selector labels (subset of common labels — must be immutable).
*/}}
{{- define "mychart.selectorLabels" -}}
app.kubernetes.io/name: {{ include "mychart.name" . }}
app.kubernetes.io/instance: {{ .Release.Name }}
{{- end }}

Pattern 2: Conditional Resources

{{- if .Values.ingress.enabled -}}
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: {{ include "mychart.fullname" . }}
  labels:
    {{- include "mychart.labels" . | nindent 4 }}
  {{- with .Values.ingress.annotations }}
  annotations:
    {{- toYaml . | nindent 4 }}
  {{- end }}
spec:
  {{- if .Values.ingress.tls }}
  tls:
    {{- range .Values.ingress.tls }}
    - hosts:
        {{- range .hosts }}
        - {{ . | quote }}
        {{- end }}
      secretName: {{ .secretName }}
    {{- end }}
  {{- end }}
  rules:
    {{- range .Values.ingress.hosts }}
    - host: {{ .host | quote }}
      http:
        paths:
          {{- range .paths }}
          - path: {{ .path }}
            pathType: {{ .pathType }}
            backend:
              service:
                name: {{ include "mychart.fullname" $ }}
                port:
                  number: {{ $.Values.service.port }}
          {{- end }}
    {{- end }}
{{- end }}

Pattern 3: Security-Hardened Pod Spec

spec:
  serviceAccountName: {{ include "mychart.serviceAccountName" . }}
  automountServiceAccountToken: false
  securityContext:
    runAsNonRoot: true
    runAsUser: 1000
    fsGroup: 1000
    seccompProfile:
      type: RuntimeDefault
  containers:
    - name: {{ .Chart.Name }}
      securityContext:
        allowPrivilegeEscalation: false
        readOnlyRootFilesystem: true
        capabilities:
          drop:
            - ALL
      image: "{{ .Values.image.repository }}:{{ .Values.image.tag | default .Chart.AppVersion }}"
      imagePullPolicy: {{ .Values.image.pullPolicy }}
      resources:
        {{- toYaml .Values.resources | nindent 8 }}
      volumeMounts:
        - name: tmp
          mountPath: /tmp
  volumes:
    - name: tmp
      emptyDir: {}

---

Values Design Principles

STRUCTURE
├── Flat over nested (image.tag > container.spec.image.tag)
├── Group by resource (service.*, ingress.*, resources.*)
├── Use enabled: true/false for optional resources
├── Document every key with inline YAML comments
└── Provide sensible development defaults

NAMING
├── camelCase for keys (replicaCount, not replica_count)
├── Boolean keys: use adjectives (enabled, required) not verbs
├── Nested keys: max 3 levels deep
└── Match upstream conventions (image.repository, image.tag, image.pullPolicy)

ANTI-PATTERNS
├── Hardcoded cluster URLs or domains
├── Secrets as default values
├── Empty strings where null is correct
├── Deeply nested structures (>3 levels)
├── Undocumented values
└── values.yaml that doesn't work without overrides

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Dependency Management

SUBCHARTS
├── Use Chart.yaml dependencies (not requirements.yaml — Helm 3)
├── Pin versions: version: ~15.x.x (patch float)
├── Use condition: to make optional: condition: postgresql.enabled
├── Use alias: for multiple instances of same chart
├── Override subchart values under subchart name key in values.yaml
└── Run helm dependency update before packaging

LIBRARY CHARTS
├── type: library in Chart.yaml — no templates directory
├── Export named templates only — no rendered resources
├── Use for shared labels, annotations, security contexts
└── Version independently from application charts

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Proactive Triggers

Flag these without being asked:

• No _helpers.tpl → Create one. Every chart needs standard labels and fullname helpers.
• Hardcoded image tag in template → Extract to values.yaml. Tags must be overridable.
• No resource requests/limits → Add them. Pods without limits can starve the node.
• Running as root → Add securityContext. No exceptions for production charts.
• No NOTES.txt → Create one. Users need post-install instructions.
• Secrets in values.yaml defaults → Remove them. Use placeholders with comments explaining how to provide secrets.
• No liveness/readiness probes → Add them. Kubernetes needs to know if the pod is healthy.
• Missing app.kubernetes.io labels → Add via _helpers.tpl. Required for proper resource tracking.

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Installation

One-liner (any tool)

git clone https://github.com/alirezarezvani/claude-skills.git
cp -r claude-skills/engineering/helm-chart-builder ~/.claude/skills/

Multi-tool install

./scripts/convert.sh --skill helm-chart-builder --tool codex|gemini|cursor|windsurf|openclaw

OpenClaw

clawhub install cs-helm-chart-builder

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Related Skills

• senior-devops — Broader DevOps scope (CI/CD, IaC, monitoring). Complementary — use helm-chart-builder for chart-specific work, senior-devops for pipeline and infrastructure.
• docker-development — Container building. Complementary — docker-development builds the images, helm-chart-builder deploys them to Kubernetes.
• ci-cd-pipeline-builder — Pipeline construction. Complementary — helm-chart-builder defines the deployment artifact, ci-cd-pipeline-builder automates its delivery.
• senior-security — Application security. Complementary — helm-chart-builder covers Kubernetes-level security (RBAC, pod security), senior-security covers application-level threats.