Helm Overview

Helm is the package manager for Kubernetes. It packages Kubernetes resources into reusable charts, supports parameterized deployments through values files, and simplifies upgrades, rollbacks and multi-environment deployments.

Helm Architecture

Git → CI/CD → Helm Chart → Values → Kubernetes API → Cluster

Chart Structure

mychart/
├── Chart.yaml
├── values.yaml
├── charts/
├── templates/
│   ├── deployment.yaml
│   ├── service.yaml
│   ├── ingress.yaml
│   ├── _helpers.tpl
│   └── NOTES.txt
└── .helmignore

Chart.yaml

apiVersion: v2
name: myapp
version: 1.0.0
appVersion: "1.0.0"
type: application

Values Files

image:
  repository: ghcr.io/company/app
  tag: 1.0.0
replicaCount: 3
service:
  type: ClusterIP

Templates

apiVersion: apps/v1
kind: Deployment
metadata:
  name: {{ include "myapp.fullname" . }}
spec:
  replicas: {{ .Values.replicaCount }}

Template Functions

{{ default "nginx" .Values.image.repository }}
{{ upper .Values.environment }}
{{ quote .Values.tag }}

Helpers

{{- define "myapp.fullname" -}}
{{ .Release.Name }}-{{ .Chart.Name }}
{{- end -}}

Dependencies

dependencies:
- name: redis
  version: 20.x.x
  repository: https://charts.bitnami.com/bitnami

Repositories & OCI

helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo update
helm pull oci://registry.example.com/charts/myapp

Releases

helm install app ./chart
helm list
helm status app

Upgrades & Rollbacks

helm upgrade app ./chart -f values-prod.yaml
helm history app
helm rollback app 2

GitOps

Helm integrates with Argo CD and Flux. Store charts and values in Git and let GitOps controllers synchronize cluster state automatically.

Security Best Practices

• Do not store secrets in values files.
• Use external secret managers.
• Lint charts before release.
• Pin chart versions.
• Review templates.

Troubleshooting

helm lint ./chart
helm template ./chart
helm get values app
helm history app

Useful Commands

helm create app
helm lint
helm template
helm install
helm upgrade
helm rollback
helm uninstall
helm list
helm status
helm history
helm dependency update
helm package
helm repo add
helm search repo

Key Takeaways

Helm standardizes Kubernetes application packaging and deployment. Combined with GitOps, version-controlled values and CI/CD, it enables repeatable, auditable and production-ready releases.