The Basic Model Interface (BMI): governance and decision-making

The purpose of this document is to formalize the governance process used for the Basic Model Interface (BMI) in both ordinary and extraordinary situations, and to clarify how decisions are made and how the various elements of our community interact, including the relationship between open source collaborative development and work that may be funded by for-profit or non-profit entities.


The Basic Model Interface (BMI) is a community-owned and community-run project. To the maximum extent possible, decisions about project direction are made by community consensus (but note that “consensus” here has a somewhat technical meaning that might not match everyone’s expectations–see below). Some members of the community additionally contribute by serving on the Steering Council (see below), where they are responsible for facilitating the establishment of community consensus, for stewarding project resources, and–in extreme cases–for making project decisions if the normal community-based process breaks down.

The Project

BMI is an open source software project (hereafter, the Project) affiliated with the NSF-funded Community Surface Dynamics Modeling System (CSDMS). The goal of the Project is to develop an open source software interface standard for querying and controlling models. The Project also includes tools, documentation, and examples to support and promote this standard. The software developed by the Project is released under the MIT open source license, developed openly, and hosted on public GitHub repositories under the csdms and other GitHub organization. Proposed changes to the Project must follow the CONTRIBUTING document in the Project’s main GitHub repository.

The Project is developed by a team of distributed developers, called Contributors. Contributors are individuals who have contributed code, documentation, designs, or other work to the Project. Anyone can be a Contributor. Contributors can be affiliated with any legal entity or none. Contributors participate in the project by submitting, reviewing, and discussing GitHub pull requests and issues and participating in open and public Project discussions on GitHub and other channels. The foundation of Project participation is openness and transparency.

The Project Community consists of all Contributors and Users of the Project. Contributors work on behalf of and are responsible to the larger Project Community. We strive to keep the barrier between Contributors and Users as low as possible.


This section describes the governance and leadership model of the Project. The foundations of Project governance are:

  • Openness & Transparency
  • Active Contribution
  • Institutional Neutrality

Consensus-based decision making by the community

Normally, decisions on the Project will be made by consensus of all interested Contributors. The primary goal of this approach is to ensure that the people who are most affected by and involved in any given change can contribute their knowledge in the confidence that their voices will be heard, because thoughtful review from a broad community is the best mechanism we know of for creating high-quality software.

The mechanism we use to accomplish this goal may be unfamiliar for those who are not experienced with the cultural norms around free/open-source software development. We provide a summary here, and highly recommend that all Contributors additionally read the chapter Social and Political Infrastructure of Karl Fogel’s Producing Open Source Software, and in particular the section on Consensus-based Democracy, for a more detailed discussion.

In this context, consensus does not require:

  • that we wait to solicit everyone’s opinion on every change,
  • that we ever hold a vote on anything, or
  • that everyone is happy or agrees with every decision.

For us, what consensus means is that we entrust everyone with the right to veto any change if they feel it necessary. While this may sound like a recipe for obstruction, this is not what happens. Instead, we find that most people take this responsibility seriously, and only invoke their veto when they judge that a serious problem is being ignored, and that their veto is necessary to protect the Project. In practice, it turns out that vetoes are almost never formally invoked because their mere possibility ensures that Contributors are motivated from the start to find solutions that everyone can live with, thus accomplishing our goal of ensuring that all interested perspectives are taken into account.

How do we know when consensus has been achieved? In principle, this is difficult, since consensus is defined by the absence of vetoes, which requires us to somehow prove a negative. In practice, we use a combination of our best judgment (e.g., a simple and uncontroversial bug fix posted on GitHub and reviewed by a core developer is probably fine) and best efforts (e.g., substantive changes must not only follow the Project’s CONTRIBUTING document, but also be posted to the Project’s designated communication channel in order to give the broader community a chance to catch any problems and suggest improvements; we assume that anyone who cares enough about BMI to invoke their veto right should be on the Project’s communication channel). If no one comments on the Project’s communication channel after several days, then it’s probably fine.

If one does need to invoke a formal veto, then it should consist of:

  • an unambiguous statement that a veto is being invoked,
  • an explanation of why it is being invoked, and
  • a description of what conditions (if any) would convince the vetoer to withdraw their veto.

If all proposals for resolving some issue are vetoed, then the status quo wins by default.

In the worst case, if a Contributor is genuinely misusing their veto in an obstructive fashion to the detriment of the Project, then they can be ejected from the Project by consensus of the Steering Council–see below.

Steering Council

The Project has a Steering Council (a.k.a. the BMI Council) that consists of Project Contributors and Users. The overall role of the Council is to ensure, with input from the Community, the long-term well-being of the Project, both technically and as a community.

During everyday Project activities, Council Members participate in discussions, code reviews, and other Project activities as peers with all other Contributors and the Community. In these everyday activities, Council Members do not have any special power or privilege through their membership on the Council. However, it is expected that because of the quality and quantity of their contributions and their expert knowledge of the Project that Council Members will provide useful guidance, both technical and in terms of Project direction, to potentially less experienced Contributors.

The Steering Council plays a special role in certain situations. In particular, the Council may, if necessary:

  • Make decisions about the overall scope, vision, and direction of the Project.
  • Make decisions about strategic collaborations with other organizations or individuals.
  • Make decisions about specific technical issues, features, bugs, and pull requests. They are the primary mechanism of guiding the code review process and merging pull requests.
  • Update policy documents such as this one.
  • Make decisions when regular community discussion doesn’t produce consensus on an issue in a reasonable time frame.

However, the Council’s primary responsibility is to facilitate the ordinary community-based decision making procedure described above. If the Council ever has to step in and formally override the community for the health of the Project, then they will do so, but they will consider reaching this point to indicate a failure in their leadership.

Council decision making

If it becomes necessary for the Steering Council to produce a formal decision, then they will use a form of the Apache Foundation voting process. This is a formalized version of consensus, in which +1 votes indicate agreement, -1 votes are vetoes (and must be accompanied with a rationale, as above), and fractional votes (e.g. -0.5, +0.5) can be used if one wishes to express an opinion without registering a full veto. These numeric votes can also be used informally to get a general sense of the Community’s feelings on some issue. A formal vote only occurs if explicitly declared, and if this does occur then the vote should be held open for long enough to give all interested Council Members a chance to respond–at least one week.

In practice, we anticipate that for most Council decisions (e.g., voting in new members) a more informal process will suffice.

Council membership

A list of current Steering Council Members is maintained at the page Steering Council.

To become eligible to join the Steering Council, an individual must be a Project Contributor who has produced substantial contributions or a Project User that has applied BMI in a substantial way. Candidate Council Members are nominated by existing Council Members. The Candidate must confirm they are interested and willing to serve in this capacity. The Candidate becomes a Member following consensus of the existing Council. The Council will be initially formed from a set of existing Project Contributors and Users who, as of early 2022, have been currently active in Project development or application.

When considering potential Members, the Council will look at candidates with a comprehensive view, including but not limited to code, code review, applications, infrastructure work, communication channel participation, community help/building, education and outreach, design work, etc. We are deliberately not setting arbitrary quantitative metrics (like “100 commits in this repo”) to avoid encouraging behavior that plays to the metrics rather than the Project’s overall well-being. We want to encourage a diverse array of backgrounds, viewpoints, and talents, which is why we explicitly do not define code as the sole metric on which Council membership will be evaluated.

If a Council Member becomes inactive in the Project for a period of one year, they will be considered for removal from the Council. Before removal, the inactive Member will be approached to see if they plan on returning to active participation. If not, they will be removed after a Council vote. If they plan on returning to active participation, they will be given a grace period of one year. If they do not return to active participation within that time period they will be removed by vote of the Council without further grace period. All former Council Members can be considered for membership again at any time in the future, like any other Project Contributor or User. Retired Council members will be listed on the project website, acknowledging the period during which they were active in the Council.

The Council reserves the right to eject current Members if they are deemed to be actively harmful to the Project’s well-being, and if attempts at communication and conflict resolution have failed. This requires the consensus of the remaining Members.

Conflict of interest

It is expected that Council Members will be employed at a range of universities, government agencies, companies, and non-profit organizations. Because of this, it is possible that Members will have conflict of interests. Such conflict of interests include, but are not limited to:

  • Financial interests, such as investments, employment or contracting work, outside of the Project that may influence their work on the Project.
  • Access to proprietary information of their employer that could potentially leak into their work with the Project.

All members of the Council shall disclose to the rest of the Council any conflict of interest they may have. Members with a conflict of interest in a particular issue may participate in Council discussions on that issue, but must recuse themselves from voting on the issue.

Private communications of the Council

To the maximum extent possible, Council discussions and activities will be public and done in collaboration and discussion with the Project Contributors and Community. The Council will have a private communication channel that will be used sparingly and only when a specific matter requires privacy. When private communications and decisions are needed, the Council will do its best to summarize those to the Community after eliding personal/private/sensitive information that should not be posted to the public internet.


The Council can create subcommittees that provide leadership and guidance for specific aspects of the Project. Like the Council as a whole, subcommittees should conduct their business in an open and public manner unless privacy is specifically called for. Private subcommittee communications should happen on the communication channel of the Council unless specifically called for.

Institutional Partners and Funding

The Steering Council is the primary leadership for the Project. No outside institution, individual, or legal entity has the ability to own, control, usurp or influence the Project other than by participating in the Project as Contributors and Council Members. However, because institutions can be an important funding mechanism for the project, it is important to formally acknowledge institutional participation in the Project. These are Institutional Partners.

An Institutional Contributor is any individual Project Contributor who contributes to the project as part of their official duties as an Institutional Partner. Likewise, an Institutional Council Member is any Project Steering Council Member who contributes to the Project as part of their official duties as an Institutional Partner.

With these definitions, an Institutional Partner is any recognized legal entity in the United States or elsewhere that employs at least one Institutional Contributor or Institutional Council Member. Institutional Partners can be for-profit or non-profit entities.

Institutions become eligible to become an Institutional Partner by employing individuals who actively contribute to the Project as part of their official duties. To state this another way, the only way for a Partner to influence the project is by actively contributing to the open development of the Project, in equal terms to any other Contributor or Council Member. Merely using Project software in an institutional context does not allow an entity to become an Institutional Partner. Financial gifts do not enable an entity to become an Institutional Partner. Once an institution becomes eligible for Institutional Partnership, the Steering Council must nominate and approve the Partnership.

If at some point an existing Institutional Partner stops having any contributing employees, then a one-year grace period commences. If at the end of this one year period they continue not to have any contributing employees, then their Institutional Partnership will lapse, and resuming it will require going through the normal process for new Partnerships.

An Institutional Partner is free to pursue funding for their work on the Project through any legal means. This could involve a non-profit organization raising money from private foundations and donors or a for-profit company building proprietary products and services that leverage Project software and services. Funding acquired by Institutional Partners to work on the Project is called Institutional Funding. However, no funding obtained by an Institutional Partner can override the Steering Council. If a Partner has funding to do Project work and the Council decides to not pursue that work, the Partner is free to pursue it on their own. However in this situation, that part of the Partner’s work will not be under the Project umbrella and cannot use the Project trademarks in a way that suggests a formal relationship.

Institutional Partner benefits are:

  • Acknowledgement on Project websites, in talks, and on promotional material.
  • Ability to acknowledge their own funding sources on Project websites, in talks, and on promotional material.
  • Ability to influence the Project through the participation of their Council Member.

A list of current Institutional Partners is maintained at the page Institutional Partners.


Substantial portions of this document were adapted from the NumPy governance document.


To the extent possible under law, the authors have waived all copyright and related or neighboring rights to the BMI project governance and decision-making document, as per the CC-0 public domain dedication / license.