Helm is ubiquitous in Kubernetes ecosystems. Most organizations use it to package and deploy applications, and many third-party tools (Prometheus, NGINX Ingress, cert-manager) are installed via Helm charts. Interviewers test Helm knowledge to gauge whether candidates can work efficiently in real production environments.
Basic questions cover chart structure and common commands: "What files does a Helm chart contain?" and "How do you upgrade a release with new values?" Intermediate questions explore template functions, conditionals, and how values from multiple sources are merged. A frequent practical question is "How would you roll back a failed Helm release?"
Advanced interviews may ask about chart development best practices: library charts, dependency management, testing with helm test, and the trade-offs between Helm and Kustomize. Candidates should also understand how Helm stores release metadata (as Secrets or ConfigMaps in the release namespace) and the security implications of chart repositories.
Hooks are an important but often overlooked topic. Being able to explain how pre-install and post-upgrade hooks work — and when to use them versus init containers — shows deeper Helm fluency that interviewers appreciate.
A Helm chart is a package of pre-configured Kubernetes resource templates. Helm is the package manager for Kubernetes, enabling you to define, install, and upgrade complex applications using reusable, versioned chart packages with customizable values.