EKS Helm & Package Management

1. What is a Helm Chart? Think of a Helm Chart as a Blueprint. Instead of writing a hardcoded “Deployment” where the image is always nginx:1.24, you write a Template.

• Templates: These are YAML files with “placeholders” (e.g., image: {{ .Values.image.repository }}).
• Values (values.yaml): This is the “Data Center.” It’s a simple file where you define what those placeholders should be (e.g., repository: nginx).

When you run helm install, Helm takes the Template + the Values and “bakes” them into a final Kubernetes YAML that it sends to the API server.

2. The 2026 Standard: Application vs. Library Charts In 2026, we don’t just copy-paste charts. We categorize them:

• Application Charts: A chart you can actually install (e.g., your Frontend app).
• Library Charts: A “Helper” chart that doesn’t deploy anything itself but contains common logic (like standard labels or security settings) that all your other charts “borrow.” This keeps your code DRY (Don’t Repeat Yourself).

3. Mastering Versioning (SemVer) In a DevSecOps environment, versioning is everything. Helm uses Semantic Versioning (MAJOR.MINOR.PATCH):

• MAJOR: Breaking changes (e.g., you renamed a mandatory field in values.yaml).
• MINOR: New features (e.g., you added an optional “Monitoring” toggle).
• PATCH: Bug fixes (e.g., you fixed a typo in a health check).
• AppVersion: This is separate! It tells you the version of the code inside (e.g., v2.4.0), while the Chart Version tells you the version of the blueprint.