Kubernetes Operator Tutorial - Build Production-Ready Operators

This Kubernetes Operator tutorial takes you from the reconcile loop and Custom Resource Definitions all the way to a production-grade controller with leader election, admission webhooks, Prometheus metrics, and an OLM bundle ready for OperatorHub. Across 28 lessons in 9 chapters, every example is built on the standard stack — controller-runtime, kubebuilder, and Operator SDK — and tested on real kind and Minikube clusters.

Start with Chapter 1 if Operators are new to you. We begin with what an Operator actually is, how it differs from a plain controller and from a CRD, and the reconcile loop that powers every Operator on the planet. By the end of Chapter 5 you understand the full conceptual stack — CRDs, controller-runtime internals, finalizers, owner references, drift detection, Server-Side Apply — and have everything you need to read or audit any open-source Operator on GitHub.

Chapter 6 adds admission webhooks; Chapter 7 covers the production concerns that decide whether an Operator survives in a real cluster — RBAC scoping, leader election, health probes, Prometheus metrics, and multi-tenancy. Chapters 8 and 9 then walk through two of the lower-friction paths to shipping an Operator: pure Helm-based Operators (when your day-2 logic is light) and hybrid Helm + Go Operators (when you need Helm's templating but Go's reconciliation).

If you already understand the basics, jump straight to any chapter — each lesson is self-contained but the order is designed to build on the previous topic.

Click Start the course to begin with "What is a Kubernetes Operator?", or use the syllabus to skip directly to the chapter you need.