Contributing to Flux

Flux is Apache 2.0 licensed and accepts contributions via GitHub pull requests. This document outlines some of the conventions on to make it easier to get your contribution accepted.

We gratefully welcome improvements to issues and documentation as well as to code.

Certificate of Origin

By contributing to this project you agree to the Developer Certificate of Origin ( This document was created by the Linux Kernel community and is a simple statement that you, as a contributor, have the legal right to make the contribution.

We require all commits to be signed. By signing off with your signature, you certify that you wrote the patch or otherwise have the right to contribute the material by the rules of the DCO:

Signed-off-by: Jane Doe <>

The signature must contain your real name (sorry, no pseudonyms or anonymous contributions) If your and are configured in your Git config, you can sign your commit automatically with git commit -s.


For realtime communications we use Slack: To join the conversation, simply join the CNCF Slack workspace and use the #flux-dev channel.

To discuss ideas and specifications we use Github Discussions.

For announcements we use a mailing list as well. Simply subscribe to flux-dev on to join the conversation (there you can also add calendar invites to your Google calendar for our Flux meeting).

Understanding Flux and the GitOps Toolkit

If you are entirely new to Flux and the GitOps Toolkit, you might want to take a look at the introductory talk and demo.

This project is composed of:

Understanding the code

To get started with developing controllers, you might want to review our guide which walks you through writing a short and concise controller that watches out for source changes.

How to run the test suite


  • go >= 1.16
  • kubectl >= 1.18
  • kustomize >= 3.1

You can run the unit tests by simply doing

make test

The e2e test suite uses kind for running kubernetes cluster inside docker containers. You can run the e2e tests by simply doing

make setup-kind
make e2e

# When done
make cleanup-kind

Acceptance policy

These things will make a PR more likely to be accepted:

  • a well-described requirement
  • tests for new code
  • tests for old code!
  • new code and tests follow the conventions in old code and tests
  • a good commit message (see below)
  • all code must abide Go Code Review Comments
  • names should abide What’s in a name
  • code must build on both Linux and Darwin, via plain go build
  • code should have appropriate test coverage and tests should be written to work with go test

In general, we will merge a PR once one maintainer has endorsed it. For substantial changes, more people may become involved, and you might get asked to resubmit the PR or divide the changes into more than one PR.

Format of the Commit Message

For the GitOps Toolkit controllers we prefer the following rules for good commit messages:

  • Limit the subject to 50 characters and write as the continuation of the sentence “If applied, this commit will …”
  • Explain what and why in the body, if more than a trivial change; wrap it at 72 characters.

The following article has some more helpful advice on documenting your work.