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containerd Project Governance

As a CNCF member project, we abide by the CNCF Code of Conduct.

For specific guidance on practical contribution steps for any containerd sub-project please see our guide.


There are different types of maintainers, with different responsibilities, but all maintainers have 3 things in common:

  1. They share responsibility in the project's success.
  2. They have made a long-term, recurring time investment to improve the project.
  3. They spend that time doing whatever needs to be done, not necessarily what is the most interesting or fun.

Maintainers are often under-appreciated, because their work is harder to appreciate. It's easy to appreciate a really cool and technically advanced feature. It's harder to appreciate the absence of bugs, the slow but steady improvement in stability, or the reliability of a release process. But those things distinguish a good project from a great one.


A reviewer is a core maintainer within the project. They share in reviewing issues and pull requests and their LGTM counts towards the required LGTM count to merge a code change into the project.

Reviewers are part of the organization but do not have write access. Becoming a reviewer is a core aspect in the journey to becoming a committer.


A committer is a core maintainer who is responsible for the overall quality and stewardship of the project. They share the same reviewing responsibilities as reviewers, but are also responsible for upholding the project bylaws as well as participating in project level votes.

Committers are part of the organization with write access to all repositories. Committers are expected to remain actively involved in the project and participate in voting and discussing of proposed project level changes.

Adding maintainers

Maintainers are first and foremost contributors that have shown they are committed to the long term success of a project. Contributors wanting to become maintainers are expected to be deeply involved in contributing code, pull request review, and triage of issues in the project for more than three months.

Just contributing does not make you a maintainer, it is about building trust with the current maintainers of the project and being a person that they can depend on and trust to make decisions in the best interest of the project.

Periodically, the existing maintainers curate a list of contributors that have shown regular activity on the project over the prior months. From this list, maintainer candidates are selected and proposed in the maintainers forum.

After a candidate has been informally proposed in the maintainers forum, the existing maintainers are given seven days to discuss the candidate, raise objections and show their support. Formal voting takes place on a pull request that adds the contributor to the MAINTAINERS file. Candidates must be approved by 2/3 of the current committers by adding their approval or LGTM to the pull request. The reviewer role has the same process but only requires 1/3 of current committers.

If a candidate is approved, they will be invited to add their own LGTM or approval to the pull request to acknowledge their agreement. A committer will verify the numbers of votes that have been received and the allotted seven days have passed, then merge the pull request and invite the contributor to the organization.

For non-core sub-projects, only committers of the repository that the candidate is proposed for are given votes.

Security Advisors

A security advisor is an advisory role in the project responsible for helping classify and advise on embargoed security disclosures. Security advisors are individuals trusted by maintainers and representing significant users of the project.

Security advisors are part of the organization without write access, but with read access to security disclosures and advisories before becoming public. There is no expectation of advisors to become reviewers or participate in issue triage and code review. Security advisors help maintain the integrity of the security review process and encourage responsible disclosure.

A reviewer may also be a security advisor, however, committers do not need this role as it is part of their regular duties. The security advisor duties are not part of the duties of being a reviewer.

Candidates should contact a maintainer and request sponsorship for becoming a security advisor. Once a maintainer is willing to sponsor a candidate, the maintainer will open up a pull request to the SECURITY_ADVISORS files adding the candidate. Since it is not expected that candidates are active in the project, there is no expectation that they are well known by a majority of maintainers. Approving the pull request requires a two LGTM threshold of committers. A reviewer may sponsor themselves, but still require the same two LGTM threshold of committers.

Security advisors may be removed by the same sponsoring maintainer with a two LGTM threshold or by any other maintainer with approval of 1/3 of current committers.


containerd subprojects are divided into two flavors currently: core and non-core. Most of the repositories within the containerd GitHub organization are "core" to the delivery of the containerd runtime project's releases. For example, the Golang implementations of the cgroups, runc, and console APIs, the ttrpc implementation, and various built-in plugins like the CRI implementation. These, among a handful of other repositories, are all core and required pieces which culminate in officially supported and maintained releases of containerd.

Non-core projects have a strong affiliation with the containerd runtime, but operate similarly to the traditional contrib/ directory in many open source projects. In most cases the maintainer list will be unique and the project can have unique release, support, and maintainer processes. Non-core projects may be written in other languages and therefore require different skills, developer tools, and CI systems than the core projects. For these reasons, non-core subprojects have a few unique properties that are described in the section "Adding non-core subprojects" below.

Both core and non-core subprojects must adhere to the CNCF charter and mission.

Adding core subprojects

New core subprojects can request to be added to the containerd GitHub organization by submitting a project proposal via public forum (a containerd/project GitHub issue is the easiest way to provide this proposal). The existing maintainers are given seven days to discuss the new project, raise objections and cast their vote. Projects must be approved by 2/3 of the current core committers.

If a project is approved, a maintainer will add the project to the containerd GitHub organization, and make an announcement on a public forum.

Please add the suggested text from our Project core documents section to your

Adding non-core subprojects

Non-core subprojects will also submit a project proposal via public forum, and should state that the project is expected to be non-core.

The proposal should include a proposed list of maintainers who will manage the non-core project and provide general information on support, releases, stability, and any additional detail useful for the containerd maintainers to understand the scope and nature of the project.

The existing maintainers are given seven days to discuss the new project, raise objections and cast their vote. Projects must be approved by 2/3 of the current core committers.

If a project is approved, a core maintainer will add the project to the containerd GitHub organization and provide write access for that repository to the proposed maintainer list, as well as make an announcement on a public forum.

Unlike core maintainers, non-core project maintainers are responsible for maintenance tasks in their subproject only. Core maintainers have maintainer privileges across all core and non-core projects to help contribute to project health, maintenance, and release processes within the GitHub organization. For ease of list management, the MAINTAINERS file of a non-core project will only list the non-core project maintainers—the core maintainers of containerd will not be appended to each subproject.

Please add the suggested text from our Non-core project documents section to your

Stepping down policy

Life priorities, interests, and passions can change. If you're a maintainer but feel you must remove yourself from the list, inform other maintainers that you intend to step down, and if possible, help find someone to pick up your work. At the very least, ensure your work can be continued where you left off.

After you've informed other maintainers, create a pull request to remove yourself from the MAINTAINERS file.

Removal of inactive maintainers

Similar to the procedure for adding new maintainers, existing maintainers can be removed from the list if they do not show significant activity on the project. Periodically, the maintainers review the list of maintainers and their activity over the last year.

If a maintainer has shown insufficient activity over this period, a neutral person will contact the maintainer to ask if they want to continue being a maintainer. If the maintainer decides to step down as a maintainer, they open a pull request to be removed from the MAINTAINERS file.

If a committer is unable to continue participating in project level votes but wishes to remain a maintainer on the project, they may convert their role to a reviewer until they are able to perform committer duties again.

If an inactive maintainer wants to remain in their current role or does not open their own pull request to change roles, another maintainer may open up a pull request to the MAINTAINERS file to change their role. Role changes and removals must be approved by 2/3 of the current committers. The voting and discussion period is seven days, after which a committer will verify the votes, merge the pull request, and apply the changes to the organization.

How are decisions made?

containerd is an open-source project with an open design philosophy. This means that the repository is the source of truth for EVERY aspect of the project, including its philosophy, design, road map, and APIs. If it's part of the project, it's in the repo. If it's in the repo, it's part of the project.

As a result, all decisions can be expressed as changes to the repository. An implementation change is a change to the source code. An API change is a change to the API specification. A philosophy change is a change to the philosophy manifesto, and so on.

All decisions affecting containerd, big and small, follow the same 3 steps:

  • Step 1: Open a pull request. Anyone can do this.

  • Step 2: Discuss the pull request. Anyone can do this.

  • Step 3: Merge or refuse the pull request. Who does this depends on the nature of the pull request and which areas of the project it affects.

Helping contributors with the DCO

The DCO or Sign your work requirement is not intended as a roadblock or speed bump.

Some containerd contributors are not as familiar with git, or have used a web based editor, and thus asking them to git commit --amend -s is not the best way forward.

In this case, maintainers can update the commits based on clause (c) of the DCO. The most trivial way for a contributor to allow the maintainer to do this, is to add a DCO signature in a pull requests's comment, or a maintainer can simply note that the change is sufficiently trivial that it does not substantially change the existing contribution - i.e., a spelling change.

When you add someone's DCO, please also add your own to keep a log.

I'm a maintainer. Should I make pull requests too?

Yes. Nobody should ever push to main directly. All changes should be made through a pull request.

Conflict Resolution

If you have a technical dispute that you feel has reached an impasse with a subset of the community, any contributor may open an issue, specifically calling for a resolution vote of the current core committers to resolve the dispute. A resolution vote must be approved by 2/3 of the current core committers.