Why Kubernetes Is Dropping Docker Support and What It Means for You

Kubernetes 1.20 was released, and one major change is the deprecation of Docker support, which will be removed in future versions.

This change caused a stir; why is K8s dropping Docker and how does it affect us?

K8s Why Deprecate Docker?

In short, supporting Docker is too costly for Kubernetes.

First , Docker is heavyweight.

Docker includes many components such as:

CLI

API

Server

Container Runtime

Volumes

Network

Build image

Kubernetes only uses the container runtime part.

Second , Kubernetes had to develop and maintain a separate component called dockershim to bridge Docker, because Docker does not implement the CRI standard.

Dockershim is a temporary solution, and its long‑term maintenance becomes increasingly problematic (e.g., incompatibility with cgroups v2, user namespaces).

Based on these reasons, Kubernetes decided to drop Docker support.

What Does This Mean for Us?

Kubernetes supports container runtimes that follow the OCI (Open Container Initiative) standard, including:

containerd

CRI‑O

Docker‑built images already comply with OCI, so they run in Kubernetes without issues.

Therefore, developers can continue using Docker as before.

For developers, there is no impact; CI/CD pipelines remain unchanged; tools like MiniKube and Docker Desktop are unaffected.

The impact is mainly on Kubernetes operators, who need to replace Docker with containerd or CRI‑O as the new container runtime.

Feel free to share your thoughts in the comments.

References:

https://kubernetes.io/blog/2020/12/08/kubernetes-1-20-release-announcement/

https://medium.com/dev-genius/no-docker-isnt-dead-2b9ee45d5833

https://medium.com/better-programming/kubernetes-is-deprecating-docker-8a9f7566fbca