The App Store for Kubernetes
Where do you find Charts? You don't always have to write them yourself — and for common infrastructure software, you almost never should.
Just as Linux uses package repositories to distribute software, Helm uses Chart Repositories: HTTP servers that host packaged .tgz chart archives along with an index.yaml file that lists available charts and their versions.
Artifact Hub (artifacthub.io) is a web-based search engine that indexes charts from dozens of public repositories. If you need to install common software like Prometheus, Grafana, MongoDB, Nginx Ingress Controller, or cert-manager onto Kubernetes, your first stop should be Artifact Hub to find an official or well-maintained community chart.
Working with Repositories
The basic workflow is: add a repository to the local Helm client, refresh the local cache of what it offers, search it for a chart, then install a specific chart — optionally pinned to a specific version rather than whatever is latest.
Inspecting a Chart Before Installing
Before installing a third-party chart, you should always inspect its default values and understand what it will deploy — Helm can show a chart's full set of configurable values and their defaults, its metadata (version, description, dependencies), and can render its templates locally without deploying anything at all, as a dry run.
The dry-run mode is particularly important in production workflows: it renders all templates and validates them against the Kubernetes API Server without actually creating any resources, catching configuration errors before they cause an outage.
A common interview question is: "How do you safely upgrade a Helm release in production?" The expected answer covers several steps: (1) run helm diff upgrade (using the helm-diff plugin) to preview exactly what will change, (2) use --dry-run to validate the rendered manifests, (3) pin a specific chart version with --version, and (4) have a rollback plan ready with helm rollback. Mentioning helm history to inspect revision state shows operational maturity.