Writing a Kubernetes CSI Driver: Controller and Node from Scratch

Fri, 24 Apr 2026 09:00:00 +0000

Kubernetes storage is one of those areas that looks simple from the outside — you create a PersistentVolumeClaim, a pod mounts it, done. But the moment you need to integrate your own storage backend, you’re staring at the Container Storage Interface spec, sidecar containers you’ve never heard of, and gRPC services that have to be wired together just right.

I had the pleasure of writing and contributing to a production-grade CSI driver end-to-end. This post covers everything I wish I had in one place: what CSI actually is, how Kubernetes orchestrates it, and how to implement all three services in Go.

Grpc on Anton Antonov's mindspace

Writing a Kubernetes CSI Driver: Controller and Node from Scratch