From CRDs to Controllers: Building a Kubernetes Custom Controller from Scratch

📰 Dev.to · Ankur Sinha

Learn to build a Kubernetes custom controller from scratch, leveraging CRDs and Controllers for efficient workflow orchestration

intermediate Published 24 Feb 2026

Action Steps

Define a Custom Resource Definition (CRD) using YAML or JSON to specify the structure of your custom resource
Create a new Go module for your controller project and initialize it with the necessary dependencies
Implement the controller logic using the Kubernetes Go client library to watch and manage your custom resources
Build and deploy your custom controller to a Kubernetes cluster using kubectl or another deployment tool
Test and validate your custom controller's functionality using kubectl and other debugging tools

Who Needs to Know This

DevOps engineers and Kubernetes developers can benefit from this knowledge to streamline workflow management and automation

Key Insight

💡 Custom controllers can be used to extend Kubernetes' functionality and automate complex workflows

Key Takeaways

Learn to build a Kubernetes custom controller from scratch, leveraging CRDs and Controllers for efficient workflow orchestration

If you’ve worked with Kubernetes, you’ve probably seen how it can orchestrate complex workflows using...