* 📝 Re-write and extend Deployment guide: Concepts, Uvicorn, Gunicorn, Docker, Containers, Kubernetes. PR [#3974](https://github.com/tiangolo/fastapi/pull/3974) by [@tiangolo](https://github.com/tiangolo).
* 📝 Upgrade HTTPS guide with more explanations and diagrams. PR [#3950](https://github.com/tiangolo/fastapi/pull/3950) by [@tiangolo](https://github.com/tiangolo).

### Deployment
* **[beta]** Deployments that cannot make progress in rolling out the newest version will now indicate via the API they are blocked ([docs](https://kubernetes.io/docs/user-guide/deployments/#deployment-status))

### Federation

### Promoted Server Side Unknown Field Validation to Beta

- Kubeadm: remove the deprecated "kubeadm alpha kubelet config enable-dynamic" command. To continue using the feature please defer to the guide for "Dynamic Kubelet Configuration" at k8s.io. This change also removes the parent...

Continuous integration builds have used the following versions of external dependencies, however, this is not a strong recommendation and users should consult an appropriate installation or upgrade guide before deciding what versions of etcd, docker or rkt to use.

* Docker versions 1.10.3, 1.11.2, 1.12.6 have been validated

    * Docker version 1.12.6 known issues

or use cri-dockerd if you are relying on Docker Engine as your container runtime.
For more information about ensuring your cluster is ready for this removal, please
see [this guide](https://kubernetes.io/blog/2022/03/31/ready-for-dockershim-removal/).

### Beta APIs Off by Default

[New beta APIs will not be enabled in clusters by default](https://github.com/kubernetes/enhancements/issues/3136).

## Urgent Upgrade Notes 

### (No, really, you MUST read this before you upgrade)

- Deprecated beta APIs scheduled for removal in `v1.26` are no longer served. See https://kubernetes.io/docs/reference/using-api/deprecation-guide/#v1-26 for more information. ([#111973](https://github.com/kubernetes/kubernetes/pull/111973), [@liggitt](https://github.com/liggitt))

ion`, `CustomResourceDefinition`, `APIService`, `TokenReview`, `SubjectAccessReview`, `CertificateSigningRequest`, `Lease`, `Ingress`, and `IngressClass` APIs. For the full list check out [Deprecated API Migration Guide](https://kubernetes.io/docs/reference/using-api/deprecation-guide/#v1-22) and the blog post [Kubernetes API and Feature Removals In 1.22: Here’s What You Need To Know](https://blog.k8s.io/2021/07/14/upcoming-changes-in-kubernetes-1-22/).

### Kubernetes release cadence...

* kubeadm: add a preflight check that throws a warning if the cgroup driver for Docker on Linux is not "systemd" as per the k8s.io CRI installation guide. ([#73837](https://github.com/kubernetes/kubernetes/pull/73837), [@neolit123](https://github.com/neolit123))

## Major themes

Kubernetes is developed by community members whose work is organized into
[Special Interest Groups](https://github.com/kubernetes/community/blob/master/sig-list.md), which provide the themes that guide their work. For the 1.9 release, these themes included:

### API Machinery

Extensibility. SIG API Machinery added a new class of admission control webhooks (mutating), and brought the admission control webhooks to beta.