1. Introduction & Overview
What is Helm?
Helm is a package manager for Kubernetes that helps define, install, and manage Kubernetes applications. It simplifies the deployment and lifecycle management of applications by using reusable YAML templates called charts. Helm enables repeatable builds, consistent deployments, and version-controlled infrastructure as code (IaC).
History or Background
- Helm 1.0 was introduced by Deis (acquired by Microsoft) in 2015.
- Evolved through several iterations:
- Helm 2 included Tiller (server-side component).
- Helm 3 (released in 2019) removed Tiller, improving security and aligning better with Kubernetes RBAC.
- Helm is now part of the Cloud Native Computing Foundation (CNCF).
Why is It Relevant in DevSecOps?
- Automates secure application deployment across environments.
- Enables infrastructure as code (IaC), key for compliance and reproducibility.
- Integrates with CI/CD pipelines for secure, consistent deployments.
- Supports parameterization, versioning, and immutable deployments—core DevSecOps principles.
2. Core Concepts & Terminology
Key Terms and Definitions
| Term | Description |
|---|---|
| Chart | A package of pre-configured Kubernetes resources. |
| Release | A running instance of a chart in a Kubernetes cluster. |
| Values.yaml | File to customize configurations for templates. |
| Template | Go-based templates for Kubernetes manifests. |
| Repository | Stores Helm charts. Can be public (ArtifactHub) or private. |
How It Fits Into the DevSecOps Lifecycle
| DevSecOps Phase | Helm’s Role |
|---|---|
| Plan | Define application structure and required dependencies. |
| Build | Package charts as artifacts in CI pipelines. |
| Test | Deploy test environments using parameterized charts. |
| Release | Push Helm charts to registries and deploy using CD tools. |
| Operate | Manage upgrades, rollbacks, and monitor releases. |
| Secure | Embed security policies and secrets as part of deployment logic. |
3. Architecture & How It Works
Components of Helm
- Helm CLI: Interface to interact with Kubernetes using Helm commands.
- Charts: Directories containing Kubernetes manifest templates and metadata.
- Repositories: Hosts for sharing and storing charts (e.g., ChartMuseum, GitHub).
- Kubernetes API Server: Executes actual resource deployment.
Internal Workflow
- User runs a
helm installorhelm upgrade. - Helm CLI renders the templates using
values.yaml. - Kubernetes manifests are created.
- Resources are deployed via the Kubernetes API.
- Helm maintains release history in cluster secrets or ConfigMaps.
Architecture Diagram Description (Textual)
- User/CI/CD pipeline → Helm CLI
- Pulls chart from Helm Repository
- Renders templates using Values.yaml
- Sends manifests to Kubernetes API Server
- Resources get deployed into the Kubernetes Cluster
Integration Points with CI/CD and Cloud Tools
| Tool | Integration Example |
|---|---|
| GitHub Actions | Use Helm in deployment jobs for Kubernetes clusters. |
| GitLab CI/CD | Automate Helm-based releases via helm upgrade. |
| Argo CD | GitOps-based deployment using Helm charts. |
| Terraform | Call Helm charts as modules via helm_release resource. |
| AWS/GCP/Azure | Deploy charts into managed Kubernetes clusters like EKS, GKE, AKS. |
4. Installation & Getting Started
Basic Setup or Prerequisites
- A running Kubernetes cluster (minikube, EKS, GKE, etc.)
- kubectl CLI installed and configured
- Helm 3.x installed
- Optional: Docker, Git, and a CI/CD environment (GitHub Actions/GitLab)
Hands-On: Step-by-Step Beginner-Friendly Setup
Step 1: Install Helm
curl https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3 | bash
Step 2: Add a Chart Repository
helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo update
Step 3: Install a Chart
helm install my-nginx bitnami/nginx
Step 4: List Releases
helm list
Step 5: Upgrade the Release
helm upgrade my-nginx bitnami/nginx --set service.type=LoadBalancer
Step 6: Uninstall
helm uninstall my-nginx
5. Real-World Use Cases
1. Secure Microservice Deployment
- Helm chart templates define Kubernetes resources.
- Inject secrets via sealed-secrets or HashiCorp Vault.
- Integrate with Snyk or Trivy to scan Helm charts before release.
2. Policy Enforcement in CI/CD
- Use OPA/Gatekeeper policies embedded in Helm charts.
- Ensure security policies are version-controlled.
3. Environment Replication
- Promote Helm-based releases from dev to staging to prod using GitOps.
- Reuse charts with different
values.yamlfiles.
4. Multi-Tenant SaaS Deployments
- Helm supports templating tenant-specific namespaces, secrets, and configurations.
- Automate per-tenant deployments with dynamic values.
6. Benefits & Limitations
Key Advantages
- Reusability: Parameterized templates.
- Speed: Rapid deployment using declarative definitions.
- Version Control: Release history and rollback.
- Integration: Works with most CI/CD and cloud tools.
- Security: Encourages separation of concerns (infrastructure vs secrets).
Common Challenges or Limitations
- Template Complexity: Can be hard to debug.
- Limited Validation: Does not enforce schema validation by default.
- Secret Management: Native support is weak; best when combined with external tools.
- Learning Curve: Requires familiarity with Kubernetes internals.
7. Best Practices & Recommendations
Security Tips
- Never hardcode secrets in
values.yaml; use sealed-secrets or external secret managers. - Enable Helm chart linting using
helm lint. - Use static analysis tools like
kube-scoreorpluto.
Performance & Maintenance
- Limit chart complexity—split large charts.
- Use chart dependencies wisely to reduce bloat.
- Archive deprecated releases.
Compliance & Automation Ideas
- Integrate Helm chart validation into CI workflows.
- Include security scanning of templates in pipelines.
- Use signed charts to ensure provenance.
8. Comparison with Alternatives
| Tool | Helm | Kustomize | Terraform |
|---|---|---|---|
| Focus | Package mgmt | Resource customization | Infra orchestration |
| Declarative | ✅ | ✅ | ✅ |
| Templating | Go templates | YAML patches | HCL |
| Best Use Case | App deployment | Fine-tuning resources | Infra provisioning |
| DevSecOps Fit | ✅ High | ✅ Medium | ✅ High |
When to Choose Helm
- When deploying repetitive workloads in Kubernetes.
- If parameterization and versioning are required.
- When working in multi-environment or multi-team setups.
- For seamless integration with GitOps and cloud-native pipelines.
9. Conclusion
Helm is a powerful enabler for DevSecOps in Kubernetes environments. It brings together repeatable, secure, and automated deployment patterns that fit neatly into a continuous delivery lifecycle. When combined with GitOps, secrets management, and policy enforcement, Helm strengthens the DevSecOps maturity of any team.
Next Steps
- Explore Helm charts on ArtifactHub
- Learn Helm best practices from the Helm Docs
- Contribute or explore charts on GitHub Helm Repositories