Public record
Software health reportschema 0.34.0 · metrics 2.10.0 · 2026-08-27 15:56 UTC

dtolnay / cxx

Safe interop between Rust and C++

Rust · C++Apache-2.0★ 6,810 stars⑂ 419 forkssince Dec 2019View on GitHub ↗
KindLibraryCommand-line toolhow this is determined

dtolnay/cxx holds a health index of 89 out of 100, placing it in the Excellent band. It scores highest on Vitality (95/100) and lowest on AI Readiness (59/100). It was last updated 2 days ago. A single contributor accounts for most of its recent work.

89
overall / 100
Excellent

Software health index

Metrics are grouped into weighted categories on one standardized 1–100 scale. Overall starts as their weighted mean, calibrated against the distribution of the public record so bands carry percentile meaning; when public evidence triggers the High-Risk Jurisdiction Policy, the rating is adjusted and receives an At Risk ceiling of 34.

89
Exceptional93-100The record's top tier (≈ top 5%); essentially all checked criteria met
Excellent80-92Strong across the board; minor gaps
Good65-79Healthy; gaps are limited and manageable
Moderate50-64Acceptable with notable gaps; review recommended
Weak35-49Material weaknesses across several areas
At Risk20-34Significant weaknesses; adoption warrants caution
Critical1-19Severe problems (abandoned, single-maintainer, no hygiene)
VitalityCommunity &AdoptionSustainability &GovernanceEngineeringQualitySecurityAI Readiness

Score profile

Each axis is a category. The shape matters more than the average — a healthy subject fills the whole shape, while a spike-and-crater profile means strength in one dimension is masking risk in another.

The weighted overall 75 is calibrated to 89 on the published index scale (record calibration 2026-08-02).

Ownership

David TolnayPersonal account
9,725 followers122 public repossince Jul 20120xF9BA143B95FF6D82

This repository is owned by a personal account. A single-owner project carries more continuity risk than an organization-backed one.

Package ecosystems

RegistryPackageVersionDownloads / moVersionsLast publishTags
crates.iocxx1.0.1993,336,61224619 days agoc++ffino-stdapi-bindings
crates.iocxxbridge-flags1.0.1993,336,01722219 days agocompilers
crates.iocxxbridge-macro1.0.1993,337,69024519 days agoffi

Metrics by category

Vitality

Is the project alive — is code being written and are releases shipping?

95Exceptional · 21% of overall

Development activity

92Excellent
How it's scored
36/36Push recency — last push 2 days ago
28.4/36Commit cadence — 41/52 weeks with commits
18/18Commit volume — 456 commits in the last year
10/10OpenSSF Scorecard: Maintained — 30 commit(s) and 2 issue activity found in the last 90 days -- score normalized to 10
Inputs used
commits_last_year456
human_commit_share1
days_since_last_push2
active_weeks_last_year41

Release discipline

100Exceptional
How it's scored
27/27Ships releases — 100 releases published
36/36Release recency — latest release 19 days ago
27/27Release cadence — a release every ~28 days
10/10OpenSSF Scorecard: Signed-Releases — 5 out of the last 5 releases have a total of 5 signed artifacts.
Inputs used
releases_count100
latest_release_tag1.0.199
releases_from_tagsno
days_since_latest_release19
mean_days_between_releases28

Community & Adoption

Does the project have users, downloads, attention, and a welcoming setup for contributors?

87Excellent · 17% of overall

Popularity & adoption

92Excellent
How it's scored
60/60Stars — 6,810 stars
21.8/25Forks — 419 forks
9.8/15Watchers — 58 watchers
Inputs used
forks419
stars6,810
watchers58
growth_stateunverified
growth_factor_pct100
growth_unverified_reasonno_history

Community health

73Good
How it's scored
22.5/22.5README
22.5/22.5License — recognized license (Apache-2.0)
0/18CONTRIBUTING guide
13.5/13.5Code of conduct
7.2/7.2Issue template
0/6.3PR template
Inputs used
has_readmeyes
has_licenseyes
readme_badges4
has_contributingno
has_issue_templateyes
has_code_of_conductyes
readme_badge_servicesshields.io
has_pull_request_templateno

Ecosystem adoption (downloads)

100Exceptional
How it's scored
80/80Monthly downloads — 10,010,319 downloads/month across crates
0/20Registry dependents — not reported by this ecosystem
Inputs used
packagescxx, cxxbridge-flags, cxxbridge-macro
dependents—
ecosystemscrates
total_downloads224,351,115
monthly_downloads10,010,319
unverified_packages_excluded—
Excluded from scoring (no data or not applicable): Registry dependents. Remaining weights renormalized.

Sustainability & Governance

Will the project survive its people — bus factor, responsiveness, who backs it, and package upkeep?

64Moderate · 23% of overall

Maintainer resilience (bus factor)

34At Risk
How it's scored
9/54Bus factor — 1 contributor(s) cover half of all commits
1/22.5Commit distribution — top contributor authored 96% of commits
13.5/13.5Contributor breadth — 69 contributors
10/10OpenSSF Scorecard: Contributors — project has 12 contributing companies or organizations
Inputs used
bus_factor1
contributors_sampled69
top_contributor_share0.955

Issue & PR responsiveness

59Moderate
How it's scored
32.9/42Issue resolution — 78% of issues closed
25.7/30PR acceptance — 822/959 decided PRs merged
0/13Newcomer PR acceptance — 0/2 first-time contributors' PRs merged in 30d
0/15OpenSSF Scorecard: Code-Review — Found 0/22 approved changesets -- score normalized to 0
Inputs used
merged_prs822
open_issues163
closed_issues587
prs_merged_7d1
prs_decided_7d2
prs_merged_30d4
prs_decided_30d6
issue_closed_ratio0.783
closed_unmerged_prs137
first_time_authors_30d2
first_time_prs_merged_30d0
first_time_prs_decided_30d2

Ownership & stewardship

75Good
How it's scored
10/30Ownership backing — personal (user) account
0/20Verified domain — not applicable to user accounts
25/25Owner reach — 9,725 followers of dtolnay
25/25Track record — 122 public repos, account ~14 yr old
Inputs used
followers9,725
owner_typeUser
is_verified—
owner_logindtolnay
public_repos122
account_age_days5,162
Excluded from scoring (no data or not applicable): Verified domain. Remaining weights renormalized.

Package maintenance

100Exceptional
How it's scored
25/25Published & resolvable — 3 package(s) on crates
35/35Publish recency — latest publish 19 days ago
20/20Version history — 246 published versions
20/20Not deprecated — active, not deprecated or yanked
Inputs used
packagescxx, cxxbridge-flags, cxxbridge-macro
ecosystemscrates
any_deprecatedno
min_days_since_publish19

Engineering Quality

Are baseline engineering and documentation practices in place?

72Good · 19% of overall

Engineering practices

84Excellent
How it's scored
24/24CI workflows — 5 workflow(s)
24/24Tests present
16/16Linter config — book/package.json ("prettier"), eslint.config.mjs
0/9.6Pre-commit hooks
0/6.4.editorconfig
20/20OpenSSF Scorecard: CI-Tests — 6 out of 6 merged PRs checked by a CI test -- score normalized to 10
Inputs used
has_ciyes
has_testsyes
has_editorconfigno
has_linter_configyes
has_precommit_configno

Documentation

55Moderate
How it's scored
30/30README
0/25Documentation directory
15/15Documentation / homepage site — https://cxx.rs
10/10Repository description
0/10Topics
0/10Wiki
Inputs used
topics—
has_wikino
homepagehttps://cxx.rs
docs_sitehttps://cxx.rs
has_readmeyes
has_docs_dirno
has_descriptionyes

Security

Are visible security and supply-chain practices strong, without unresolved high-risk jurisdiction exposure?

62Moderate · 16% of overall

Security posture

53Moderate
How it's scored
7.5/7.5Binary-Artifacts — no binaries found in the repo
0/7.5Branch-Protection — no data
2.5/2.5CI-Tests — 6 out of 6 merged PRs checked by a CI test -- score normalized to 10
0/2.5CII-Best-Practices — no effort to earn an OpenSSF best practices badge detected
0/7.5Code-Review — Found 0/22 approved changesets -- score normalized to 0
2.5/2.5Contributors — project has 12 contributing companies or organizations
10/10Dangerous-Workflow — no dangerous workflow patterns detected
0/7.5Dependency-Update-Tool — no update tool detected
0/5Fuzzing — project is not fuzzed
2.5/2.5License — license file detected
7.5/7.5Maintained — 30 commit(s) and 2 issue activity found in the last 90 days -- score normalized to 10
0/5Packaging — no data
0/5Pinned-Dependencies — dependency not pinned by hash detected -- score normalized to 0
0/5SAST — SAST tool is not run on all commits -- score normalized to 0
1.5/5Security-Policy — security policy file detected
7.5/7.5Signed-Releases — 5 out of the last 5 releases have a total of 5 signed artifacts.
0/7.5Token-Permissions — detected GitHub workflow tokens with excessive permissions
7.5/7.5Vulnerabilities — 0 existing vulnerabilities detected
Inputs used
sourceopenssf_scorecard
checks_evaluated16
scorecard_versionv5.5.0
checks_inconclusive2
scorecard_aggregate5.3
Excluded from scoring (no data or not applicable): Branch-Protection, Packaging. Remaining weights renormalized.

Dependency advisories

100Exceptional
How it's scored
35/35Direct dependencies free of known advisories — no direct dependency carries a known advisory
0/25Indirect dependencies free of known advisories — transitive set not separable from development and test dependencies in this scope
0/40No advisories left outstanding — no advisory carries a publication date
Inputs used
sourceosv
advisories0
affected_packages0
assessed_packages115
unassessed_packages22
affected_by_severitynone
direct_affected_packages0
Excluded from scoring (no data or not applicable): Indirect dependencies free of known advisories, No advisories left outstanding. Remaining weights renormalized. Matched 115 resolved dependencies against OSV. 22 could not be assessed — no resolved version, an unsupported ecosystem, or beyond the reported package list. This repository publishes no package the index resolves, so the repository dependency graph was assessed instead. That graph mixes development and test pins with shipped dependencies, so only the declared runtime dependencies are scored; transitive findings are reported as context and excluded from the score. Reachability is not analyzed.

AI Readiness

How well is the repo equipped to be developed and maintained with AI coding agents? Carries a deliberately small weight (4%): agent tooling is a real maintenance signal, but a repository with none can still reach 100/100.

59Moderate · 4% of overall

Agent context & guidance

20At Risk
How it's scored
0/45Agent instructions — no CLAUDE.md / AGENTS.md / editor rules
0/15Machine-readable docs (llms.txt)
19.7/40Legible commit history — 37 of 100 human commits state their intent (structured subject or explanatory body)
Inputs used
has_llms_txtno
llms_txt_url—
legible_history_share0.37
agent_instruction_files—
agent_instruction_max_bytes—

Verify loop (build / test / typecheck)

72Good
How it's scored
18/18One-command bootstrap — book/diagram/Makefile
22/22Automated tests
11/11Lint / format config — book/package.json ("prettier"), eslint.config.mjs
11/11Static type checking — Rust (statically typed)
10/10Reproducible environment — devcontainer, Dockerfile, lockfile
0/10Demonstrated agent practice — no agent-authored commits among the last 100
0/8Automated maintenance — no automated dependency updates observed
0/10OpenSSF Scorecard: Pinned-Dependencies — dependency not pinned by hash detected -- score normalized to 0
Inputs used
has_nixno
has_testsyes
lockfilesCargo.lock, package-lock.json
has_dockerfileyes
typed_languageyes
bootstrap_filesbook/diagram/Makefile
has_devcontaineryes
has_linter_configyes
typecheck_configs—
agent_commit_share0
toolchain_manifestsCargo.toml, bridge/build/Cargo.toml, bridge/cmd/Cargo.toml, bridge/lib/Cargo.toml, demo/Cargo.toml, flags/Cargo.toml, macro/Cargo.toml, tests/ffi/Cargo.toml, third-party/Cargo.toml
dependency_bot_commit_share0

Code legibility for models

100Exceptional
How it's scored
45/45Type-checkable code — Rust (statically typed)
54.5/55Manageable file sizes — 2/230 source files over 60KB
Inputs used
primary_languageRust
largest_source_bytes94,834
source_files_sampled230
oversized_source_files2

Key facts

6,810GitHub stars
69contributors
456commits, last 12 months
2days since last push
100releases
1bus factor
163open issues
crates.io, npmpackage ecosystems

Data collection warnings

  • Star history unavailable: GitHub GraphQL error: Resource not accessible by personal access token
  • Could not fetch npm package 'cxx-book-build' from its registry
  • Could not fetch crates package 'third-party' from its registry

More detail

Star and fork history 0 ★ / 419 ⇿
0Stars
419Forks
100Releases

When each star and fork was added, collected from GitHub and bucketed by day. Cumulative growth sits directly above the daily additions it is made of, so the two read against each other: steady organic accretion looks nothing like an abrupt, short-lived burst. Where that difference is measurable, it is reported as growth authenticity.

010020030040050040192020-012023-052026-08
Major 0Minor 0Patch 100

Each point covers 7 days.

OpenSSF Scorecard 5.3 / 10
5.3aggregate

Independent, tool-agnostic security assessment from the open-source OpenSSF Scorecard. Each check rewards a security practice, not a specific vendor's tool. Checks Scorecard could not determine are marked n/a and excluded from the security score (never counted as zero).Scorecard v5.5.0 · 2026-08-27 15:55 UTC

10Binary-Artifactsno binaries found in the repo
n/aBranch-Protectioninternal error: error during branchesHandler.setup: internal error: some github tokens can't read classic branch protection rules: https://github.com/ossf/scorecard-action/blob/main/docs/authentication/fine-grained-auth-token.md
10CI-Tests6 out of 6 merged PRs checked by a CI test -- score normalized to 10
0CII-Best-Practicesno effort to earn an OpenSSF best practices badge detected
0Code-ReviewFound 0/22 approved changesets -- score normalized to 0
10Contributorsproject has 12 contributing companies or organizations
10Dangerous-Workflowno dangerous workflow patterns detected
0Dependency-Update-Toolno update tool detected
0Fuzzingproject is not fuzzed
10Licenselicense file detected
10Maintained30 commit(s) and 2 issue activity found in the last 90 days -- score normalized to 10
n/aPackagingpackaging workflow not detected
0Pinned-Dependenciesdependency not pinned by hash detected -- score normalized to 0
0SASTSAST tool is not run on all commits -- score normalized to 0
3Security-Policysecurity policy file detected
10Signed-Releases5 out of the last 5 releases have a total of 5 signed artifacts.
0Token-Permissionsdetected GitHub workflow tokens with excessive permissions
10Vulnerabilities0 existing vulnerabilities detected
Direct dependencies 20
RegistryPackageVersion constraintManifest
crates.iocxxbridge-macro=1.0.199Cargo.toml
crates.iofoldhash0.2Cargo.toml
crates.iolink-cplusplus1.0.11Cargo.toml
npmcheerio^1.0.0book/package.json
npmhtml-entities^2.5.2book/package.json
crates.ioindexmap2.9.0macro/Cargo.toml
crates.ioproc-macro21.0.74macro/Cargo.toml
crates.ioquote1.0.35macro/Cargo.toml
crates.iosyn3macro/Cargo.toml
crates.iocc1.0.101third-party/Cargo.toml
crates.ioclap4third-party/Cargo.toml
crates.iocodespan-reporting0.13.1third-party/Cargo.toml
crates.iofoldhash0.2third-party/Cargo.toml
crates.ioindexmap2.9.0third-party/Cargo.toml
crates.ioproc-macro21.0.58third-party/Cargo.toml
crates.ioquote1.0.4third-party/Cargo.toml
crates.iorustversion1third-party/Cargo.toml
crates.ioscratch1third-party/Cargo.toml
crates.ioserde1third-party/Cargo.toml
crates.iosyn3third-party/Cargo.toml
All dependencies 137

Full resolved dependency set from the GitHub dependency graph: 15 direct and 122 indirect (transitive) packages. The transitive closure is complete when the repository commits a lockfile.

RegistryPackageVersionRelation
crates.iocc—direct
crates.ioclap—direct
crates.iocodespan-reporting—direct
crates.iocxxbridge-macro1.0.198direct
crates.iofoldhash—direct
crates.ioindexmap—direct
crates.iolink-cplusplus—direct
crates.ioproc-macro2—direct
crates.ioquote—direct
crates.iorustversion—direct
crates.ioscratch—direct
crates.ioserde—direct
crates.iosyn—direct
npmcheerio1.2.0direct
npmhtml-entities2.6.0direct
crates.iocxx—indirect
crates.iocxx-build—indirect
crates.iocxx-build1.0.198indirect
crates.iocxx-gen—indirect
crates.iocxx-gen0.7.198indirect
crates.iocxx-test-suite—indirect
crates.iocxxbridge-cmd1.0.198indirect
crates.iocxxbridge-flags1.0.198indirect
crates.ioindoc—indirect
crates.iopkg-config—indirect
crates.ioprettyplease—indirect
crates.iotarget-triple—indirect
crates.iotempfile—indirect
crates.iotrybuild—indirect
npm@eslint-community/eslint-utils4.10.1indirect
npm@eslint-community/regexpp4.12.2indirect
npm@eslint/config-array0.21.2indirect
npm@eslint/config-helpers0.4.2indirect
npm@eslint/core0.17.0indirect
npm@eslint/eslintrc3.3.6indirect
npm@eslint/js9.39.5indirect
npm@eslint/object-schema2.1.7indirect
npm@eslint/plugin-kit0.4.1indirect
npm@humanfs/core0.19.2indirect
npm@humanfs/node0.16.8indirect
npm@humanfs/types0.15.0indirect
npm@humanwhocodes/module-importer1.0.1indirect
npm@humanwhocodes/retry0.4.3indirect
npm@types/estree1.0.9indirect
npm@types/json-schema7.0.15indirect
npmacorn8.18.0indirect
npmacorn-jsx5.3.2indirect
npmajv6.15.0indirect
npmansi-styles4.3.0indirect
npmargparse2.0.1indirect
npmbalanced-match1.0.2indirect
npmboolbase1.0.0indirect
npmbrace-expansion1.1.18indirect
npmcallsites3.1.0indirect
npmchalk4.1.2indirect
npmcheerio-select2.1.0indirect
npmcolor-convert2.0.1indirect
npmcolor-name1.1.4indirect
npmconcat-map0.0.1indirect
npmcross-spawn7.0.6indirect
npmcss-select5.2.2indirect
npmcss-what6.2.2indirect
npmdebug4.4.3indirect
npmdeep-is0.1.4indirect
npmdom-serializer2.0.0indirect
npmdomelementtype2.3.0indirect
npmdomhandler5.0.3indirect
npmdomutils3.2.2indirect
npmencoding-sniffer0.2.1indirect
npmentities4.5.0indirect
npmentities6.0.1indirect
npmentities7.0.1indirect
npmescape-string-regexp4.0.0indirect
npmeslint9.39.5indirect
npmeslint-scope8.4.0indirect
npmeslint-visitor-keys3.4.3indirect
npmeslint-visitor-keys4.2.1indirect
npmespree10.4.0indirect
npmesquery1.7.0indirect
npmesrecurse4.3.0indirect
npmestraverse5.3.0indirect
npmesutils2.0.3indirect
npmfast-deep-equal3.1.3indirect
npmfast-json-stable-stringify2.1.0indirect
npmfast-levenshtein2.0.6indirect
npmfile-entry-cache8.0.0indirect
npmfind-up5.0.0indirect
npmflat-cache4.0.1indirect
npmflatted3.4.4indirect
npmglob-parent6.0.2indirect
npmglobals14.0.0indirect
npmhas-flag4.0.0indirect
npmhtmlparser210.1.0indirect
npmiconv-lite0.6.3indirect
npmignore5.3.2indirect
npmimport-fresh3.3.1indirect
npmimurmurhash0.1.4indirect
npmis-extglob2.1.1indirect
npmis-glob4.0.3indirect
npmisexe2.0.0indirect
npmjs-yaml4.3.1indirect
npmjson-buffer3.0.1indirect
npmjson-schema-traverse0.4.1indirect
npmjson-stable-stringify-without-jsonify1.0.1indirect
npmkeyv4.5.4indirect
npmlevn0.4.1indirect
npmlocate-path6.0.0indirect
npmlodash.merge4.6.2indirect
npmminimatch3.1.5indirect
npmms2.1.3indirect
npmnatural-compare1.4.0indirect
npmnth-check2.1.1indirect
npmoptionator0.9.4indirect
npmp-limit3.1.0indirect
npmp-locate5.0.0indirect
npmparent-module1.0.1indirect
npmparse57.3.0indirect
npmparse5-htmlparser2-tree-adapter7.1.0indirect
npmparse5-parser-stream7.1.2indirect
npmpath-exists4.0.0indirect
npmpath-key3.1.1indirect
npmprelude-ls1.2.1indirect
npmpunycode2.3.1indirect
npmresolve-from4.0.0indirect
npmsafer-buffer2.1.2indirect
npmshebang-command2.0.0indirect
npmshebang-regex3.0.0indirect
npmstrip-json-comments3.1.1indirect
npmsupports-color7.2.0indirect
npmtype-check0.4.0indirect
npmundici7.29.0indirect
npmuri-js4.4.1indirect
npmwhatwg-encoding3.1.1indirect
npmwhatwg-mimetype4.0.0indirect
npmwhich2.0.2indirect
npmword-wrap1.2.5indirect
npmyocto-queue0.1.0indirect
Dependency advisories 0

This repository publishes no package the index resolves, so its own dependency graph was assessed — 115 packages, which also include development and test pins that never ship: 0 carry known advisories, of which 0 are direct. 22 could not be assessed — no resolved version, an unsupported ecosystem, or beyond the reported package list.

No known advisories affect the assessed dependencies.

An advisory means the version recorded in the dependency graph falls inside an advisory’s affected range. Reachability is not analysed, and the graph includes development and test pins — a finding may concern tooling rather than shipped software.

Raw JSON report machine-readable

Feedback

Spotted something off in this report, or have thoughts to share? Wrong measurements, missed tooling, ideas, questions — anything is welcome. Every message is read and gets a response.

The message is kept through sign-in.

Related records

Inspected repositories sharing catalogue tags or ecosystems with dtolnay/cxx. Read them side by side →

93microsoft/windows-drivers-rsPlatform that enables Windows driver development in RustExceptional88raviqqe/stakThe miniature, embeddable R7RS Scheme implementationExcellent98PyO3/pyo3Rust bindings for the Python interpreterExceptional97rust-lang/libcRaw bindings to platform APIs for RustExceptional95contentauth/c2pa-rsRust SDK for the core C2PA (Coalition for Content Provenance and Authenticity) specificationExceptional94extphprs/ext-php-rsBindings for the Zend API to build PHP extensions natively in Rust.Exceptional

Scores are signals, not warranties. They reflect publicly visible practices on GitHub — not a code audit, and not a security guarantee.

Missing data is excluded and weights renormalized, never scored as zero. Methodology is versioned and open: metrics v2.10.0, schema v0.34.0 — full methodology · metrics wiki.

How one result sits in the wider record: aggregate statistics — crates.io.