How To Contribute

Clone and Provision Environment

  1. Make sure you have a GitHub account

  2. Clone the cilium repository

    go get -d
    cd $GOPATH/src/
  3. Set up your Development Setup

  4. Check the GitHub issues for good tasks to get started.

Submitting a pull request

Contributions must be submitted in the form of pull requests against the github repository at:

  1. Fork the Cilium repository to your own personal GitHub space or request access to a Cilium developer account on Slack
  2. Push your changes to the topic branch in your fork of the repository.
  3. Submit a pull request on

Before hitting the submit button, please make sure that the following requirements have been met:

  1. Each commit compiles and is functional on its own to allow for bisecting of commits.

  2. All code is covered by unit and/or runtime tests where feasible.

  3. All changes have been tested and checked for regressions by running the existing testsuite against your changes. See the End-To-End Testing Framework section for additional details.

  4. All commits contain a well written commit description including a title, description and a Fixes: #XXX line if the commit addresses a particular GitHub issue. Note that the GitHub issue will be automatically closed when the commit is merged.

    apipanic: Log stack at debug level
    Previously, it was difficult to debug issues when the API panicked
    because only a single line like the following was printed:
    level=warning msg="Cilium API handler panicked" client=@ method=GET
    panic_message="write unix /var/run/cilium/cilium.sock->@: write: broken
    This patch logs the stack at this point at debug level so that it can at
    least be determined in developer environments.
    Fixes: #4191
    Signed-off-by: Joe Stringer <>
  5. If any of the commits fixes a particular commit already in the tree, that commit is referenced in the commit message of the bugfix. This ensures that whoever performs a backport will pull in all required fixes:

    daemon: use endpoint RLock in HandleEndpoint
    Fixes: a804c7c7dd9a ("daemon: wait for endpoint to be in ready state if specified via EndpointChangeRequest")
    Signed-off-by: André Martins <>
  6. All commits are signed off. See the section Developer’s Certificate of Origin.

  7. Pick the appropriate milestone for which this PR is being targeted to, e.g. 1.1, 1.2. This is in particular important in the time frame between the feature freeze and final release date.

  8. Pick the right release-note label

    Labels When to set
    release-note/bug This is a non-trivial bugfix
    release-note/major This is a major feature addition, e.g. Add MongoDB support
    release-note/minor This is a minor feature addition, e.g. Refactor endpoint package
  9. Verify the release note text. If not explicitly changed, the title of the PR will be used for the release notes. If you want to change this, you can add a special section to the description of the PR.

    This is a release note text


    If multiple lines are provided, then the first line serves as the high level bullet point item and any additional line will be added as a sub item to the first line.

  10. Pick the right labels for your PR:

    Labels When to set
    kind/bug This is a bugfix worth mentioning in the release notes
    kind/enhancement This is an enhancement/feature
    priority/release-blocker This PR should block the current release
    area/* Code area this PR covers
    needs-backport/X.Y PR needs to be backported to these stable releases
    pending-review PR is immediately ready for review
    wip PR is still work in progress, signals reviewers to hold.
    backport/X.Y This is backport PR, may only be set as part of Backporting process
    upgrade-impact The code changes have a potential upgrade impact

Getting a pull request merged

  1. As you submit the pull request as described in the section Submitting a pull request. One of the reviewers will start a CI run by replying with a comment test-me-please as described in Triggering Pull-Request Builds With Jenkins. If you are a core team member, you may trigger the CI run yourself.
    1. Hound: basic golang/lint static code analyzer. You need to make the puppy happy.
    2. CI / Jenkins: Will run a series of tests:
      1. Unit tests
      2. Single node runtime tests
      3. Multi node Kubernetes tests
  2. As part of the submission, GitHub will have requested a review from the respective code owners according to the CODEOWNERS file in the repository.
    1. Address any feedback received from the reviewers
    2. You can push individual commits to address feedback and then rebase your branch at the end before merging.
  3. Owners of the repository will automatically adjust the labels on the pull request to track its state and progress towards merging.
  4. Once the PR has been reviewed and the CI tests have passed, the PR will be merged by one of the repository owners. In case this does not happen, ping us on Slack.

Pull request review process


These instructions assume that whoever is reviewing is a member of the Cilium GitHub organization or has the status of a contributor. This is required to obtain the privileges to modify GitHub labels on the pull request.

  1. Review overall correctness of the PR according to the rules specified in the section Submitting a pull request.

    Set the label accordingly.

    Labels When to set
    dont-merge/needs-sign-off Some commits are not signed off
    needs-rebase PR is outdated and needs to be rebased
  2. As soon as a PR has the label pending-review, review the code and request changes as needed by using the GitHub Request Changes feature or by using Reviewable.

  3. Validate that bugfixes are marked with kind/bug and validate whether the assessment of backport requirements as requested by the submitter conforms to the Backport Criteria.

    Labels When to set
    needs-backport/X.Y PR needs to be backported to these stable releases
  4. If the PR is subject to backport, validate that the PR does not mix bugfix and refactoring of code as it will heavily complicate the backport process. Demand for the PR to be split.

  5. Validate the release-note/* label and check the PR title for release note suitability. Put yourself into the perspective of a future release notes reader with lack of context and ensure the title is precise but brief.

    Labels When to set
    dont-merge/needs-release-note Do NOT merge PR, needs a release note
    release-note/bug This is a non-trivial bugfix
    release-note/major This is a major feature addition
    release-note/minor This is a minor feature addition
  6. Check for upgrade compatibility impact and if in doubt, set the label upgrade-impact and discuss in the Slack channel.

    Labels When to set
    upgrade-impact The code changes have a potential upgrade impact
  7. When everything looks OK, approve the changes.

  8. When all review objectives for all CODEOWNERS are met and all CI tests have passed, you may set the ready-to-merge label to indicate that all criteria have been met.

    Labels When to set
    ready-to-merge PR is ready to be merged

Developer’s Certificate of Origin

To improve tracking of who did what, we’ve introduced a “sign-off” procedure.

The sign-off is a simple line at the end of the explanation for the commit, which certifies that you wrote it or otherwise have the right to pass it on as open-source work. The rules are pretty simple: if you can certify the below:

Developer Certificate of Origin
Version 1.1

Copyright (C) 2004, 2006 The Linux Foundation and its contributors.
1 Letterman Drive
Suite D4700
San Francisco, CA, 94129

Everyone is permitted to copy and distribute verbatim copies of this
license document, but changing it is not allowed.

Developer's Certificate of Origin 1.1

By making a contribution to this project, I certify that:

(a) The contribution was created in whole or in part by me and I
    have the right to submit it under the open source license
    indicated in the file; or

(b) The contribution is based upon previous work that, to the best
    of my knowledge, is covered under an appropriate open source
    license and I have the right under that license to submit that
    work with modifications, whether created in whole or in part
    by me, under the same open source license (unless I am
    permitted to submit under a different license), as indicated
    in the file; or

(c) The contribution was provided directly to me by some other
    person who certified (a), (b) or (c) and I have not modified

(d) I understand and agree that this project and the contribution
    are public and that a record of the contribution (including all
    personal information I submit with it, including my sign-off) is
    maintained indefinitely and may be redistributed consistent with
    this project or the open source license(s) involved.

then you just add a line saying:

Signed-off-by: Random J Developer <>

Use your real name (sorry, no pseudonyms or anonymous contributions.)