Helm

TL;DR

What: The package manager for Kubernetes, managing charts (packages).

Why: Simplify K8s deployments, version control releases, reusable templates, easy rollbacks.

Quick Start

Install:

# macOS
brew install helm

# Linux
curl https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3 | bash

# Verify
helm version

Add repository and install chart:

# Add official repo
helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo update

# Install nginx
helm install my-nginx bitnami/nginx

# List releases
helm list

Cheatsheet

Command	Description
helm repo add name url	Add chart repo
helm repo update	Update repos
helm search repo keyword	Search charts
helm install name chart	Install chart
helm upgrade name chart	Upgrade release
helm uninstall name	Uninstall release
helm list	List releases
helm rollback name rev	Rollback release

Gotchas

Chart structure

mychart/
  Chart.yaml          # Chart metadata
  values.yaml         # Default values
  charts/             # Dependencies
  templates/          # K8s manifests
    deployment.yaml
    service.yaml
    _helpers.tpl      # Template helpers

Chart.yaml

apiVersion: v2
name: mychart
description: A Helm chart for my app
version: 0.1.0
appVersion: "1.0.0"

dependencies:
  - name: postgresql
    version: "12.x.x"
    repository: https://charts.bitnami.com/bitnami

values.yaml

replicaCount: 2

image:
  repository: nginx
  tag: "1.25"
  pullPolicy: IfNotPresent

service:
  type: ClusterIP
  port: 80

resources:
  limits:
    cpu: 100m
    memory: 128Mi

Template example

# templates/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: {{ include "mychart.fullname" . }}
spec:
  replicas: {{ .Values.replicaCount }}
  selector:
    matchLabels:
      app: {{ include "mychart.name" . }}
  template:
    spec:
      containers:
        - name: {{ .Chart.Name }}
          image: "{{ .Values.image.repository }}:{{ .Values.image.tag }}"
          ports:
            - containerPort: {{ .Values.service.port }}

Common operations

# Install with custom values
helm install my-app ./mychart -f custom-values.yaml

# Install with set values
helm install my-app ./mychart --set replicaCount=3

# Dry run (preview)
helm install my-app ./mychart --dry-run --debug

# Upgrade release
helm upgrade my-app ./mychart --set image.tag=v2

# Rollback to previous
helm rollback my-app 1

# Show release history
helm history my-app

Next Steps

• Helm Documentation - Official docs
• Artifact Hub - Find charts
• Chart Template Guide - Templating
• Helm Best Practices - Guidelines