Selection Model

An open, data-driven model finds the riskiest of the most valuable open source projects. The OSE board manually checks top candidates in each supported ecosystem and distributes grants to eligible projects.

Principles

Key ideas behind our model design:

Transparent, measurable, and verifiable. The open source community can improve it, and OSE members can review and approve it.
Based on how the world uses open source. It finds the riskiest of the most important parts, and targets top repos responsible for 95% of ecosystem value.
Unambiguous metrics. With all other factors equal, any growth in an underlying metric of the model should clearly affect the Value or Risk of an OSS project.
Never perfect. There is no single right way to rank OSS projects for grants. Only donors should decide how to distribute the proceeds of their donations.

Ecosystems

JavaScript / TypeScript

Python

Rust

C / C++

The model links each top package to its source repository. It scores repositories on GitHub and GitLab (including self-hosted GitLab). Repositories on other hosts keep their row but get no score. C/C++ has no single registry, so the model uses install counts as an approximation of downloads.

Stages

Stage	Result
Value	Class A repos hold the top 75% of cumulative Value in an ecosystem; class B repos hold the next 20% (up to 95%). Class A is the core, ranked by `value_score` (0–100).
Risk	For each class A repo, `risk_score` (0–100, higher is riskier) is calculated from concentration, complexity, security, and maintainer workload metrics.
Eligibility	For each class A repo, the `eligible` flag is calculated from open source license, funding intent, nonprofit, and active criteria.
Due diligence	Each project gets a final score, `√(value_score × risk_score)`, so both value and risk must be high to rank high. The board performs manual eligibility checks of top candidates, sorted by score.
Distribution	The board approves the grants, and OSE pays them out to the projects.

The first three stages are automated. The last two are done by people.

Document	Type
Model repo	Current version
Stable release v1	Used for 2026 grants