contributing KEPs in SIG Node: best practices

sig-node/CONTRIBUTING.md

@@ -2,24 +2,98 @@
 
 Welcome!
 
-## For Kubernetes Contributions
+Thank you for your interest in contributing to SIG Node. SIG Node is one of the biggest SIGs in Kubernetes.
+Reliability and performance of millions of nodes running critical applications in production rely on the quality of your contribution(s).
+The diversity of workloads, environments, and the scale SIG Node needs to support makes every code change risky as all the side effects need to be evaluated.
+And the contribution can realistically only be evaluated by a small set of maintainers.
+
+Please make sure you understand and are up to the challenge. The contributing instructions are designed to help you.
+
+## For Kubernetes Code Contributions
 
 Read the [Kubernetes Contributor Guide](https://github.com/kubernetes/community/tree/master/contributors/guide#contributor-guide).
 
 If you aspire to grow scope in the SIG, please review the [SIG Node contributor ladder](./sig-node-contributor-ladder.md) for SIG specific guidance.
 
 ### For Enhancements
 
-SIG Node enhancements are available in the <https://github.com/kubernetes/enhancements/tree/master/keps/sig-node>.
+Find out if [your thing is an enhancement a.k.a KEP](https://github.com/kubernetes/enhancements/?tab=readme-ov-file#is-my-thing-an-enhancement).
+A good way to do that is to open and issue and get feedback from node reviewers and approvers. You can even come present your idea at a weekly sig-node meeting.
+
+If you plan to contribute an enhancement, please prepare yourself for at least 1 year of engagement.
+A KEP takes at least 3 kubernetes releases to move from alpha to beta to GA. If there are API / kubelet skew considerations, it may take even longer. 
+SIG Node expects contributors to commit to land a KEP to GA stage to avoid [permanent betas](https://kubernetes.io/blog/2020/08/21/moving-forward-from-beta/#avoiding-permanent-beta).
+It is always surprising how much work is needed to productize the feature after it seems complete.
+
+If you are not ready for this commitment, you can consider teaming up with other contributors in the community or contribute
+to a KEP driven by somebody else.
+
+SIG Node enhancements are available:
+- Committed KEPs [directory](https://github.com/kubernetes/enhancements/tree/master/keps/sig-node)
+- All open KEPs [tracking issues](https://github.com/kubernetes/enhancements/issues?q=is%3Aissue+is%3Aopen+label%3Asig%2Fnode+)
+
+Here are some best practices how to approach KEP development:
+It is based on a [talk](https://kcsna2023.sched.com/event/1Sp9i/implementing-a-big-feature-on-an-example-of-a-sidecar-container-kep) 
+*"Implementing a big feature on an example of a Sidecar container KEP"*
+([Recording](https://www.youtube.com/watch?v=c3iV8E8EDUA), [Slides](https://static.sched.com/hosted_files/kcsna2023/a0/KCS-NA-2023-ppt.pdf)).
+
+#### Before Starting
+
+  * **Prove the need**: Clearly articulate the problem the KEP addresses, identify the target audience, and demonstrate the community-wide benefits.  
+  * **Secure sponsorship and reviews**: Find sponsors, reviewers, and approvers early in the process to ensure alignment and avoid delays.  
+  * **Show commitment**: Demonstrate dedication to the KEP's success by actively working on its implementation and ensuring code quality.  
+  * **Manage expectations**: The KEP process takes time, anticipate at least two releases for beta and four for GA.
+
+At this stage the expectation is that the proposal is written in general-enough terms as a Google Doc for easy commenting and fast collaborative editing.
+Sharing the design document with `dev@kubernetes.io` for commenting and with SIG members `kubernetes-sig-node@googlegroups.com` for commenting or in some cases editing is a good practice.
+
+It is also very helpful to attend SIG Node weekly meeting to present your proposal. Most of the time meeting agenda is open to discuss any proposals.
+During the meeting you can gather initial feedback, find collaborators, and secure sponsorship.
+
+#### API Design
+
+  * **Define use cases and scope**: Enumerate specific use cases and define the problem's boundaries to avoid scope creep.  
+  * **Consider the bigger picture**: Illustrate how the KEP fits into the existing Kubernetes design and how it will handle future requests.  
+  * **Document decisions**: Record all design decisions, including pros, cons, and responsible individuals.  
+  * **Address potential misuse**: Anticipate potential abuse or misuse scenarios and design the API to mitigate them.  
+  * **Engage reviewers**: Utilize SIG experts for API pre-reviews and PRR pre-reviews to gain support and streamline the review process.
+
+Kubernetes API is a main interface many users experience Kubernetes. API approvers are often the most experienced
+community members, who can help ensure the feature fit Kubernetes best practices, will not break compatibility,
+and will fit nicely with other Kubernetes capabilities. Even if use cases were approved by SIG Node approvers,
+API approvers may reject the proposal and ask to redesign it.
+
+Some KEPs may go back and forth between use cases and API design for many iterations.
+This often happens when use cases are not described completely or a lot of context is lost in written feedback.
+If the KEP is going in those circles, the recommendation is to request a meeting between SIG Approvers and API approvers driven by KEP author.
+It may be a dedicated meeting or an invite of API approvers to SIG Node weekly meeting or SIG Node approvers to API meeting.
+
+Once API approval was received, SIG Node approvers will review it again as SIG always has the last word in the feature design.
+
+Note, SIG approvers may request sign offs from other SIGs like Security, Instrumentation, Storage, Networking, Windows, etc.
+The process of getting approval is generally the same.
+
+#### Implementation
+
+  * **Structure the implementation**: Divide the implementation into pre-factoring, minimal complete product, and post-API changes for better organization and review.  
+  * **Isolate feature gate logic**: Ensure the mainline code remains unaffected when the feature gate is disabled.  
+  * **Adapt and adjust**: Be prepared to modify the KEP's scope or features based on implementation challenges.  
+  * **Collaborate effectively**: Maintain communication through group chats or meetings and consider using a shared branch for better coordination.  
+  * **Improve the codebase**: Leave the code in a better state than you found it to facilitate future maintenance and enhance your credibility.
+
+By adhering to these best practices, you can increase the chances of your KEP being successfully implemented and accepted.
+
+Sometimes SIG may over-commit on KEPs for the release. And if two big KEPs touching the same code path, SIG may decide to only take one KEP for a release.
+Even if this is the case, properly structured KEP implementation will ensure that some progress was made for that release.
 
-#### Helpful Links for Sig-Node
+### Helpful Links for SIG Node
 
 **Code**:  
 
-For general code organization, read [contributors/devel/README.md](../contributors/devel/README.md) for explaining things like
+For general code organization, read [contributors/devel/README.md](../contributors/devel/README.md) to learn about things like
 `vendor/`, `staging`, etc.
 
-* Kubelet
+* kubelet
   * <https://github.com/kubernetes/kubernetes/tree/master/cmd/kubelet>
   * <https://github.com/kubernetes/kubernetes/tree/master/pkg/kubelet>
 * Probe: <https://github.com/kubernetes/kubernetes/tree/master/pkg/probe>