Discover the Power of the Helm Template Behind Your Favorite DevOps Tools

Helm Template Prologue - Kubernetes (K8)

Kubernetes is powerful. It’s the gold standard for container orchestration—offering flexibility, resilience, and scalability.

But writing Kubernetes YAML manifests? That’s another story.

From Pods, Deployments, and Services to Ingresses, ConfigMaps, and Secrets, Kubernetes demands a lot of YAML. It gets verbose. Repetitive. Error-prone. Deploying across environments like dev, staging, and prod? Suddenly you’re managing dozens of files with nearly identical content.

Enter: the Helm Template

Let’s say you’re deploying a simple web app. The raw Kubernetes YAML might look like this:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-web-app-deployment
  labels:
    app: my-web-app
spec:
  replicas: 3
  template:
    metadata:
      labels:
        app: my-web-app
    spec:
      containers:
      - name: my-web-app
        image: my-docker-repo/my-web-app:1.0.0
        ports:
        - containerPort: 80
        env:
        - name: API_URL
          value: "http://internal-api:5000"

If you have multiple services, a database, a cache, and different configurations for dev, staging, and production, you can quickly end up with dozens or even hundreds of these files to manage. Making a simple change (like updating an image tag or changing a replica count) means hunting through files and manually editing them across different directories.

There had to be a better way. And there is. Enter Helm and Helm templates.

Helm Template Examples; Helm: Your Friendly Kubernetes Package Manager

Think of Helm like the apt or yum or npm of Kubernetes. It's a tool designed to help you define, install, and upgrade even the most complex Kubernetes applications using something called Helm Charts.

What's a Chart? At its core, a Helm Chart is a package containing all the necessary resources and information needed to deploy an application (or a set of applications) onto a Kubernetes cluster.

A typical chart includes:

1. Templates: These are your standard Kubernetes manifest files (Deployment, Service, etc.) but with placeholders (using Go templating).
2. Values: A separate file (values.yaml) where you define the configuration options for your application. These values populate the placeholders in your templates.
3. Chart.yaml: Metadata about the chart (name, version, description).

This simple structure is incredibly powerful. Instead of manually editing dozens of YAML files for each deployment or each environment, you define your application structure once in the templates and manage environment-specific configurations in the values.yaml file.

Here's what that same Deployment snippet might look like as a Helm template:

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# my-web-app/templates/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: {{ include "my-web-app.fullname" . }} # Dynamic naming using helper template
  labels:
    {{ include "my-web-app.labels" . | nindent 4 }} # Dynamic labels
spec:
  replicas: {{ .Values.replicaCount }} # Now driven by values!
  selector:
    matchLabels:
      {{ include "my-web-app.selectorLabels" . | nindent 6 }}
  template:
    metadata:
      labels:
        {{ include "my-web-app.selectorLabels" . | nindent 8 }}
    spec:
      containers:
      - name: {{ .Chart.Name }}
        image: "{{ .Values.image.repository }}:{{ .Values.image.tag | default .Chart.AppVersion }}" # Image details from values/chart
        imagePullPolicy: {{ .Values.image.pullPolicy }}
        ports:
        - containerPort: {{ .Values.service.port }} # Port from values
        env: # Environment variables from values
        {{- toYaml .Values.env | nindent 8 }} # Dump env vars from values
        resources:
          {{- toYaml .Values.resources | nindent 10 }} # Resources from values

And the corresponding values.yaml file:

# my-web-app/values.yaml
replicaCount: 3 # Easily change this per environment!

image:
  repository: my-docker-repo/my-web-app
  tag: "1.0.0" # Change this single value to update the image!
  pullPolicy: IfNotPresent

service:
  type: ClusterIP
  port: 80

env: # Define all your env vars here
  API_URL: "http://internal-api:5000"

resources: # Define resource limits here
  limits:
    cpu: "500m"
    memory: "256Mi"
  requests:
    cpu: "250m"
    memory: "128Mi"

# You might have different values files for different environments (e.g., values-prod.yaml)

You also have a simple Chart.yaml providing metadata:

# my-web-app/Chart.yaml
apiVersion: v2 # Helm Chart API version
name: my-web-app # The name of the chart
description: A Helm chart for my web application
type: application
version: 0.1.0 # The chart version
appVersion: "1.0.0" # The application version

With this structure, managing configurations and deployments becomes much simpler. You update values.yaml (or use environment-specific value overrides) and let Helm render the final YAML manifests for you.

Why Helm Became the De Facto Standard

Helm isn't just popular by chance. It solves real problems and brings some serious benefits to the table:

• Packaging Standard: Provides a consistent way to package Kubernetes applications, making them easy to share and reuse.
• Templating Power: Reduces repetition and allows for dynamic configuration based on input values.
• Release Management: Tracks installations and upgrades as "releases," making rollbacks straightforward if something goes wrong.
• Dependency Management: Easily define and manage dependencies between different charts (e.g., your application chart might depend on a database chart).
• Community & Ecosystem: A vast repository of pre-built charts for popular applications (databases, monitoring tools, etc.) available in artifact hubs like Artifact Hub.

Helm significantly streamlines the deployment lifecycle, turning that YAML spaghetti into a neatly organized package.

Why Kapstan Uses Helm Templates Under the Hood

Now, let's talk about Kapstan. Kapstan is designed with a clear goal: to abstract away the inherent complexity of Kubernetes YAML and provide developers with an intuitive UI to deploy and manage their applications. You, as the developer, interact with a friendly interface, define your application's needs, and Kapstan handles the rest, provisioning and configuring the necessary resources in your own cloud-hosted K8s cluster.

So, why would Kapstan, a tool built to hide K8s complexity, choose to rely on Helm underneath? This is where the magic of smart abstraction comes in.

Kapstan didn't need to reinvent the wheel of Kubernetes packaging, templating, and release management. Helm already does that, and it does it exceptionally well.

Here's why leveraging Helm was a brilliant move for Kapstan:

1. Leveraging a Standard: Helm is the industry standard. By building on top of Helm, Kapstan aligns itself with the established best practices and tooling in the K8s ecosystem.
2. Built-in Capabilities: Helm provides robust features like templating, value overrides, release tracking, and dependency management out-of-the-box. Kapstan gets all these powerful capabilities for free, without having to build them from scratch.
3. Reducing Development Effort: Instead of building its own complex deployment engine from the ground up, Kapstan can focus on its core value proposition: providing a simple, intuitive user interface and workflow. Helm handles the heavy lifting of translating application configurations into deployable Kubernetes objects and managing their lifecycle.
4. Access to the Ecosystem: While Kapstan users might not directly interact with the underlying Helm charts via the UI, the underlying compatibility means Kapstan could potentially leverage or be influenced by the broader Helm ecosystem if needed.
5. Maintainability & Reliability: Relying on a mature, widely-used tool like Helm generally leads to a more stable and maintainable system compared to a custom, proprietary deployment engine.

Essentially, Helm provides the powerful, flexible, and standardized engine for packaging and deploying Kubernetes applications. Kapstan then builds a beautiful, easy-to-use dashboard on top of that engine. Kapstan provides engineering teams the power of Kubernetes without the YAML.

With Kapstan, Helm templates are invisible—but invaluable.

The Best of Both Worlds; Helm & No Helm / YAML

For Developers

For developers using Kapstan, the experience is seamless. They don't need to write a single line of YAML or understand the intricacies of Helm charts. They interact with a UI that asks for the relevant application configurations – image name, ports, environment variables, resource limits – the things a developer cares about.

Underneath that clean interface, Kapstan is taking those simple inputs and intelligently mapping them to the values.yaml of a pre-defined, well-structured Helm chart. It then uses the Helm CLI to render the final Kubernetes manifests and deploy them to the cluster, managing the release process.

For Platform Engineers

For platform engineers, this architecture opens up a lot more possibilities. They can plug their own internal Helm repositories into the Kapstan platform to enable the same intuitive experience for their developers, with all the governance built-in. This transforms Kapstan into a powerful central tool for managing and deploying your organization's standard application components defined as Helm charts, seamlessly bridging the gap between platform control and developer autonomy. We’ve provided this example for you to see.

You get the power and flexibility of Kubernetes deployments, managed by the robust capabilities of Helm, all presented through Kapstan's simplifying UI. That's smart technology working for you.

So, the next time you deploy an application effortlessly through Kapstan's interface, give a little nod to Helm working hard behind the scenes, enabling that simplicity by handling the Kubernetes complexity it was designed for. It's a great example of how layering smart tools on top of established foundations leads to a much better developer experience.

Conclusion: Helm Templates Made Simple

Whether you’re deploying manually or through a platform like Kapstan, Helm templates offer the power and flexibility Kubernetes demands—without the mess of managing raw YAML.

Kapstan wraps that power in an interface anyone can use, letting you deploy confidently, scale quickly, and never touch another multiline YAML unless you want to.

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