:lock: Trezor Firmware Monorepo
C-Rank Grade: A (Welcoming) - 68/100
External PR Merge Rate: 64%
Response Time: 14h
First Timer Success: 53%
trezor/trezor-firmware has a recorded first-timer success rate of 52.6%. Repositories ranked A typically provide actionable feedback during code reviews and actively nurture new community contributors.
Maintainers in trezor/trezor-firmware respond to incoming external pull requests in approximately 13.6 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 67.9 places trezor/trezor-firmware in the A tier.
The external contributor pull request merge rate for trezor/trezor-firmware is 63.9%, based on public PR activity from non-core contributors.
trezor/trezor-firmware currently has 8 active issue(s) tagged with beginner-friendly labels like "good first issue", "beginner", or "up-for-grabs".
Collaborative maintainer environment in trezor/trezor-firmware. Reviews community pull requests with focus on project quality.
Discussions in trezor/trezor-firmware focus heavily on practical implementation feedback, code formatting standards, and issue reproduction details.
Unlinked PRs without issue context and changes that fail automated test suites face the highest review friction.
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/trezor/trezor-firmware?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
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Detected: UTC
Maintainers are most responsive around 15:00 UTC (15:00 UTC in your timezone). Recommended submission window is Tuesday - Thursday from 12:00 to 16:00 UTC (12:00 - 16:00 UTC local).
Maintainer Strategy: Maintainer Sweet Spot: PRs under 150 lines merge in ~16 hours (80% approval). Large PRs (>500 lines) take ~115 hours (29% approval). Keep your diff compact for rapid review.
T3W1 tutorial stack usage can be optimized by moving the individual screens to the heap via GcBox. See #7721 (comment)_
Summary In core/embed/rust/src/ui/shape/canvas/rgba8888.rs, the blend_pixel method for Rgba8888Canvas computes alpha-blended color channels using u16 arithmetic before converting the result to u32. Since fg_mul, bg_mul, and the channel values (fg_r/fg_g/fg_b, bg_r/bg_g/bg_b) are all u16, the intermediate multiplication and addition (fg_r * fg_mul + bg_r * bg_mul) can overflow u16::MAX (e.g. 255 * 255 + 255 * 255 = 130050), before the final / 255 and conversion to u32. This can produce incorrect blended colors, particularly around 50% alpha values. Affected code File: core/embed/rust/src/ui/shape/canvas/rgba8888.rs, in Canvas::blend_pixel for Rgba8888Canvas (around lines 118-123). let fg_mul = u16::from(alpha); let bg_mul = u16::from(255 - alpha); let r = u32::from((fg_r * fg_mul + bg_r * bg_mul) / 255); let g = u32::from((fg_g * fg_mul + bg_g * bg_mul) / 255); let b = u32::from((fg_b * fg_mul + bg_b * bg_mul) / 255); Suggested fix Widen the multiplication/addition arithmetic to u32 be
trezor-thp brings its own, then there's trezor-crypto binding, possibly more in trezorhal
Some edge cases are not covered by our regular usage, e.g. b157fcf
Tested correct truncation of non-ASCII label 012345678901234567čřž: Originally posted by @romanz in #6728 (comment)
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When evaluating whether to contribute to trezor/trezor-firmware, 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 trezor/trezor-firmware acknowledge new external contributions in approximately 13 hours. Out of all submitted pull requests from non-core authors in the last 180-day window, 63.9% were successfully merged into the primary branch.
trezor/trezor-firmware has a recorded first-timer success rate of 52.6%. Repositories ranked Welcoming typically provide actionable feedback during code reviews and actively nurture new community contributors.
The initial maintainer response time averages ~13 hours. 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 67.9 places trezor/trezor-firmware in the Welcoming tier.
The external pull request merge rate is 63.9%. GetMerged isolates non-core community contributions so external developers get an accurate benchmark of PR acceptance probability.
Yes, trezor/trezor-firmware currently has 8 active issue(s) tagged with beginner-friendly labels. You can inspect these directly from the repository issues tab.
All metrics displayed for trezor/trezor-firmware 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.