Essential Open Source Software for Science (Cycle 6)

Funding Agency:
Chan Zuckerberg Initiative

Open source software is critical to modern scientific research, advancing biology and medicine while providing reproducibility and transparency. Hundreds of software packages, libraries, and applications have become essential tools for research—so much so that many researchers could not continue their work without them. Despite its importance, even the most widely-used research software often lacks dedicated funding for maintenance, growth, development, and community engagement. Also, those who work on such software often lack credit and recognition.

In an effort to support open source software for science, the Chan Zuckerberg Initiative (CZI), the Wellcome Trust (Wellcome), and The Kavli Foundation (Kavli) (“The Funders”) seek letters of intent to apply for funding for software projects that are essential to biomedical research. Ideal applications will have previously demonstrated impact, currently show potential for continued improvement, and expect to deliver added value to the biomedical research community through the proposed activities.

Note this is a two step application process: an initial Letter of Intent (LOI), which will be followed by invitations to a select number of applicants to submit a Full Application.

With this program, we aim to provide software projects with resources to support their tools and the communities behind them. Whether it’s hiring an additional developer, improving documentation, addressing usability, improving compatibility, onboarding contributors, or convening a community, we hope our support can help make the computational foundations of biological research more usable and robust.

Deadline for Letter of Intent: Oct. 17, 2023

Agency Website

Areas of Interest

For this Request For Applications, we seek to support software tools across a broad range of biomedical fields, including (but not limited to)

  • Imaging
  • Single-Cell Biology
  • Neuroscience
  • Bioinformatics
  • Genomics
  • Structural Biology
  • Clinical Biology
  • Infectious Disease
  • Data Visualization
  • Data Analysis, Machine Learning, and AI
  • Data Management and Workflows

Applications for two broad categories of open source software projects will be considered in scope:

  • Domain-specific software for analyzing, visualizing, and otherwise working with the specific data types that arise in biomedical science. Software will be considered out of scope if it primarily serves domains outside biomedical science without strong evidence of adoption in biomedicine.
  • Foundational tools and infrastructure that enable a wide variety of downstream software across several domains of science and computational research. While foundational tools will be considered in scope for this program, they must have demonstrated impact on some area(s) of biomedical research.

Eligibility Requirements

  • Applications may be submitted by domestic and foreign nonprofit and for-profit organizations, public and private institutions, such as colleges, universities, hospitals, laboratories, units of state and local government, companies, and eligible agencies of the federal government. As part of the application process, for-profit organizations may need to provide additional information on the charitable purposes of the proposal and will only be eligible for funding from a subset of the funders. Grants are not permitted to individuals, only to organizations. Open source software projects operating independently must be affiliated with an organization, as described below.
  • If an application does not come from an organization eligible to receive and distribute funds (e.g., an academic institution), it may designate a fiscal sponsor (e.g., NumFOCUSCode for Science & Society, or others). We encourage proposals that require fiscal sponsorship to contact the appropriate organizations early in the application process. If your application requires a fiscal sponsor, you must secure one by the full proposal application deadline. Please note that applications utilizing a fiscal sponsorship may only be eligible for funding from a subset of the funders or be subject to additional processes upon award.
  • We will consider and potentially fund multiple applications from the same organization, multiple applications related to the same open source software project(s), and multiple applications that include the same staff and/or software project contributors. However, the proposed work in such applications must be distinct.
  • We encourage proposals supporting multiple open source software projects. In the case of applications for work spanning multiple software projects, one individual must complete the application and a single organization or fiscal sponsor must coordinate the dispersal of funds to the members of the collaboration. Note that non-U.S. institutions may not issue subcontracts to U.S. institutions (if funded by CZI), so please be mindful when selecting the applicant organization.
  • We encourage proposals that are currently funded from all five previous cycles of the EOSS RFA to submit an application to continue or build on the previously funded work.
  • We believe that the strongest teams incorporate a wide range of voices. Those underrepresented in science and technology are strongly encouraged to apply.

Amount Description

Applications can request funding between $50,000 USD and $200,000 USD total costs per year for two years (inclusive of up to 15% for indirect/overhead costs) for an overall amount requested between $100,000 USD and $400,000 USD total costs for the two-year duration of the grant. Proposals will not need to provide a detailed budget or justification at the LOI stage. At the full proposal stage, budgets will be required and evaluated for appropriateness relative to the scope of work proposed.

Funding Type



Women and minorities encouraged


Engineering and Physical Sciences
Environmental & Life Sciences
Medical - Basic Science
Medical - Clinical Science
Medical - Translational

External Deadline

October 17, 2023