An extremely fast Python package and project manager, written in Rust.
C-Rank Grade: A (Welcoming) - 65/100
External PR Merge Rate: 59%
Response Time: -
First Timer Success: 36%
astral-sh/uv has a recorded first-timer success rate of 36.4%. Repositories ranked A typically provide actionable feedback during code reviews and actively nurture new community contributors.
Maintainers in astral-sh/uv respond to incoming external pull requests in approximately 0.0 hours on average. Keeping PRs focused on single tasks and ensuring tests pass helps maintainers review faster.
The C-Rank™ system evaluates GitHub projects on a 0–100 scale using real data: PR merge rates, review turnaround time, active maintainer presence, and first-time contributor success. A score of 65.4 places astral-sh/uv in the A tier.
The external contributor pull request merge rate for astral-sh/uv is 58.5%, based on public PR activity from non-core contributors.
astral-sh/uv currently has 1 active issue(s) tagged with beginner-friendly labels like "good first issue", "beginner", or "up-for-grabs".
Balanced & professional review environment in astral-sh/uv. Maintains strict focus on technical quality and test standards.
Average Response Latency
Tracks hours until a maintainer leaves a review, comment, or PR response.
External Acceptance Rate
Percentage of community pull requests successfully merged into main.
First PR Conversion
Rate at which developers submitting their first repository PR succeed.
Show contributors that your repository actively reviews and merges external pull requests.
[](https://getmerged.abhishekco.de/astral-sh/uv?utm_source=github&utm_medium=badge)
Historical health & responsiveness evolution
External PR acceptance
First PR success rate
50% receive response in
90% receive response in
Maintainer review activity heatmap & prime window prediction
Calculating local time...
Calculating local time...
Detected: UTC
Maintainers are most responsive around 14:00 UTC (14:00 UTC in your timezone). Recommended submission window is Monday - Wednesday from 13:00 to 17:00 UTC (13:00 - 17:00 UTC local).
Maintainer Strategy: Maintainer Sweet Spot: PRs under 150 lines merge in ~16 hours (73% approval). Large PRs (>500 lines) take ~115 hours (26% approval). Keep your diff compact for rapid review.
We got reports that uv overruns the default open files limit (ulimit) for users on Linux and macOS: During sync/building packages: #11296 During bytecode compilation: #16999 When uninstall Python versions (no GitHub issue yet) The default ulimits can be low, for example 1024 on linux, and we spawn up to a thread per core and several subprocesses. However, Cargo and other Rust tools which have very similar workloads and often very similar problems to us, don't have any problems with ulimits. A cargo maintainer told us: From my testing for fine grain locking (unstable feature), I found that Cargo generally peaks with around ~70-80 file descriptors opened at once, and this remainly mostly static even for large projects. So the question is, why are we running into the ulimit, while Cargo doesn't? What file descriptors is uv even holding, do we need them? Is Cargo doing something different that we can adopt to avoid this? This requires some Unix expertise and rust parallelism knowledge,
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When evaluating whether to contribute to astral-sh/uv, response velocity and maintainer engagement are crucial. GetMerged continuously tracks pull request trajectories, first-comment latency, and code review rounds to help developers avoid submitting pull requests to backlogged repositories.
Currently, maintainers of astral-sh/uv acknowledge new external contributions in approximately -. Out of all submitted pull requests from non-core authors in the last 180-day window, 58.5% were successfully merged into the primary branch.
astral-sh/uv has a recorded first-timer success rate of 36.4%. Repositories ranked Welcoming typically provide actionable feedback during code reviews and actively nurture new community contributors.
The initial maintainer response time averages ~-. Keeping PRs scoped to single concerns and ensuring CI checks succeed will optimize review turnaround.
The C-Rank™ index scores repositories on a 0 to 100 scale using an objective formula: external PR merge rates, initial response speed, active maintainer count, and first-time contributor retention. A score of 65.4 places astral-sh/uv in the Welcoming tier.
The external pull request merge rate is 58.5%. GetMerged isolates non-core community contributions so external developers get an accurate benchmark of PR acceptance probability.
Yes, astral-sh/uv currently has 1 active issue(s) tagged with beginner-friendly labels. You can inspect these directly from the repository issues tab.
All metrics displayed for astral-sh/uv are automatically retrieved via the public GitHub API and recalculated daily. Insider pull requests submitted by repository owners or organization members are excluded from merge rate calculations to preserve objective external contributor statistics.