Helm
Helm is the package manager for Kubernetes, enabling you to define, install, and upgrade complex applications using charts. It is a CNCF graduated project.
Overview
Helm uses a packaging format called charts - a collection of files that describe a related set of Kubernetes resources. Charts can be stored in repositories, OCI registries, or local directories.
Key Concepts
| Concept | Description |
|---|---|
| Chart | A Helm package containing Kubernetes resource templates |
| Repository | A place where charts are collected and shared |
| Release | An instance of a chart running in a Kubernetes cluster |
| Values | Configuration options that can be injected into templates |
Documentation Index
Getting Started
- commands - Complete Helm CLI commands reference
- charts - Chart structure, templates, values, and dependencies
- library-charts - Creating shared library charts for code reuse
Testing & Quality
- testing - Chart testing, linting, and validation
Production & Operations
- production - Multi-cluster, multi-environment deployments
- oci - OCI registries, provenance, and chart signing
- troubleshooting - Debugging failed releases and rollback strategies
CI/CD & GitOps
Quick Reference
# Install a chart
helm install <release-name> <chart>
# Upgrade a release
helm upgrade <release-name> <chart>
# Rollback to previous revision
helm rollback <release-name>
# List all releases
helm list
# Get values for a release
helm get values <release-name>
# Template locally (dry-run)
helm template <release-name> <chart>
# Install with values file
helm install -f values.prod.yaml myapp ./mychart
# Upgrade with atomic rollback on failure
helm upgrade --install --atomic myapp ./mychartHelm 4 vs Helm 3
Helm 4 introduces several breaking changes and new features:
| Feature | Change |
|---|---|
| Post-renderers | Now implemented as plugins |
| Registry login | Domain name only, no URL scheme |
| Server-side apply | Default for new installs |
| CLI flags | --atomic → --rollback-on-failure, --force → --force-replace |
| Plugin system | WebAssembly-based runtime for enhanced security |
| Multi-document values | Split complex values across multiple YAML files |
Chart Repository
Charts are available on:
- Artifact Hub - Search 800+ charts from multiple repositories
- CNCF Landscape - Enterprise-grade charts