Public record
Software health reportschema 0.16.0 · metrics 2.10.0 · 2026-07-21 01:57 UTC

boxed / mutmut

Mutation testing system

PythonBSD-3-Clause★ 1,354 stars⑂ 159 forkssince Nov 2016View on GitHub ↗
KindLibraryCommand-line toolTerminal interfacehow this is determined
#testing#mutation-testing#python

boxed/mutmut holds a health index of 90 out of 100, placing it in the Excellent band. It scores highest on Engineering Quality (94/100) and lowest on AI Readiness (56/100). It was last updated 4 days ago. A single contributor accounts for most of its recent work.

90
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.

90
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 76 is calibrated to 90 on the published index scale (record calibration 2026-08-02).

Ownership

Anders HovmöllerPersonal account
178 followers165 public repossince Jul 2010@Dryft-Technologies

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
PyPImutmut3.6.0-6244 days agomutmutmutantmutationtesttesting

Metrics by category

Vitality

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

85Excellent · 21% of overall

Development activity

88Excellent
How it's scored
36/36Push recency — last push 4 days ago
24.2/36Commit cadence — 35/52 weeks with commits
18/18Commit volume — 127 commits in the last year
10/10OpenSSF Scorecard: Maintained — 29 commit(s) and 21 issue activity found in the last 90 days -- score normalized to 10
Inputs used
commits_last_year127
human_commit_share—
days_since_last_push4
active_weeks_last_year35

Release discipline

80Excellent
How it's scored
16.2/27Ships releases — 60 version tags (no GitHub releases)
36/36Release recency — latest release 44 days ago
19.8/27Release cadence — a release every ~65.8 days
0/10OpenSSF Scorecard: Signed-Releases — no data
Inputs used
releases_count60
latest_release_tag3.6.0
releases_from_tagsyes
days_since_latest_release44
mean_days_between_releases65.8
Excluded from scoring (no data or not applicable): OpenSSF Scorecard: Signed-Releases. Remaining weights renormalized.

Community & Adoption

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

73Good · 17% of overall

Popularity & adoption

75Good
How it's scored
50.8/60Stars — 1,354 stars
18.3/25Forks — 159 forks
5.8/15Watchers — 12 watchers
Inputs used
forks159
stars1,354
watchers12
growth_stateunverified
growth_factor_pct100
growth_unverified_reasonno_history

Community health

70Good
How it's scored
22.5/22.5README
22.5/22.5License — recognized license (BSD-3-Clause)
18/18CONTRIBUTING guide
0/13.5Code of conduct
0/7.2Issue template
0/6.3PR template
Inputs used
has_readmeyes
has_licenseyes
readme_badges—
has_contributingyes
has_issue_templateno
has_code_of_conductno
readme_badge_services—
has_pull_request_templateno

Sustainability & Governance

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

67Good · 23% of overall

Maintainer resilience (bus factor)

40Weak
How it's scored
9/54Bus factor — 1 contributor(s) cover half of all commits
7.8/22.5Commit distribution — top contributor authored 65% of commits
13.5/13.5Contributor breadth — 44 contributors
10/10OpenSSF Scorecard: Contributors — project has 3 contributing companies or organizations -- score normalized to 10
Inputs used
bus_factor1
contributors_sampled44
top_contributor_share0.653

Issue & PR responsiveness

76Good
How it's scored
36.2/42Issue resolution — 86% of issues closed
24.3/30PR acceptance — 174/215 decided PRs merged
0/13Newcomer PR acceptance — no first-time contributor's PR decided in 30d
6/15OpenSSF Scorecard: Code-Review — Found 6/15 approved changesets -- score normalized to 4
Inputs used
merged_prs174
open_issues44
closed_issues276
prs_merged_7d—
prs_decided_7d—
prs_merged_30d—
prs_decided_30d—
issue_closed_ratio0.863
closed_unmerged_prs41
first_time_authors_30d—
first_time_prs_merged_30d—
first_time_prs_decided_30d—
Excluded from scoring (no data or not applicable): Newcomer PR acceptance. Remaining weights renormalized.

Ownership & stewardship

64Moderate
How it's scored
10/30Ownership backing — personal (user) account
0/20Verified domain — not applicable to user accounts
16.2/25Owner reach — 178 followers of boxed
25/25Track record — 165 public repos, account ~16 yr old
Inputs used
followers178
owner_typeUser
is_verified—
owner_loginboxed
public_repos165
account_age_days5,850
Excluded from scoring (no data or not applicable): Verified domain. Remaining weights renormalized.

Package maintenance

100Exceptional
How it's scored
25/25Published & resolvable — 1 package(s) on pypi
35/35Publish recency — latest publish 44 days ago
20/20Version history — 62 published versions
20/20Not deprecated — active, not deprecated or yanked
Inputs used
packagesmutmut
ecosystemspypi
any_deprecatedno
min_days_since_publish44

Engineering Quality

Are baseline engineering and documentation practices in place?

94Exceptional · 19% of overall

Engineering practices

90Excellent
How it's scored
24/24CI workflows — 1 workflow(s)
24/24Tests present
16/16Linter config
9.6/9.6Pre-commit hooks
0/6.4.editorconfig
16/20OpenSSF Scorecard: CI-Tests — 16 out of 18 merged PRs checked by a CI test -- score normalized to 8
Inputs used
has_ciyes
has_testsyes
has_editorconfigno
has_linter_configyes
has_precommit_configyes

Documentation

100Exceptional
How it's scored
30/30README
25/25Documentation directory
15/15Documentation / homepage site — https://mutmut.readthedocs.io
10/10Repository description
10/10Topics — 3 topics
10/10Wiki
Inputs used
topicstesting, mutation-testing, python
has_wikiyes
homepagehttps://mutmut.readthedocs.io
docs_sitehttps://mutmut.readthedocs.io
has_readmeyes
has_docs_diryes
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 — branch protection not enabled on development/release branches
2/2.5CI-Tests — 16 out of 18 merged PRs checked by a CI test -- score normalized to 8
0/2.5CII-Best-Practices — no effort to earn an OpenSSF best practices badge detected
3/7.5Code-Review — Found 6/15 approved changesets -- score normalized to 4
2.5/2.5Contributors — project has 3 contributing companies or organizations -- score normalized to 10
10/10Dangerous-Workflow — no dangerous workflow patterns detected
7.5/7.5Dependency-Update-Tool — update tool detected
0/5Fuzzing — project is not fuzzed
2.5/2.5License — license file detected
7.5/7.5Maintained — 29 commit(s) and 21 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
0/5Security-Policy — security policy file not detected
0/7.5Signed-Releases — no data
0/7.5Token-Permissions — detected GitHub workflow tokens with excessive permissions
6.8/7.5Vulnerabilities — 1 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): Packaging, Signed-Releases. Remaining weights renormalized.

Dependency advisories

100Exceptional
How it's scored
35/35Direct dependencies free of known advisories — no direct dependency carries a known advisory
25/25Indirect dependencies free of known advisories — no indirect dependency carries a known advisory
0/40No advisories left outstanding — no advisory carries a publication date
Inputs used
sourceosv
advisories0
affected_packages0
assessed_packages19
unassessed_packages0
affected_by_severitynone
direct_affected_packages0
Excluded from scoring (no data or not applicable): No advisories left outstanding. Remaining weights renormalized. Matched the pypi:mutmut@3.6.0 runtime dependency closure — what installing the published package pulls in — 19 packages. 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.

56Moderate · 4% of overall

Agent context & guidance

1Critical
How it's scored
0/45Agent instructions — no CLAUDE.md / AGENTS.md / editor rules
0/15Machine-readable docs (llms.txt)
0/40Legible commit history — no data
Inputs used
has_llms_txtno
llms_txt_url—
legible_history_share—
agent_instruction_files—
agent_instruction_max_bytes—
Excluded from scoring (no data or not applicable): Legible commit history. Remaining weights renormalized.

Verify loop (build / test / typecheck)

88Excellent
How it's scored
18/18One-command bootstrap — docs/Makefile
22/22Automated tests
11/11Lint / format config
11/11Static type checking — mypy.ini, src/mutmut/py.typed
10/10Reproducible environment — Dockerfile, lockfile
0/10Demonstrated agent practice — no data
0/8Automated maintenance — no data
0/10OpenSSF Scorecard: Pinned-Dependencies — dependency not pinned by hash detected -- score normalized to 0
Inputs used
has_nixno
has_testsyes
lockfilesuv.lock
has_dockerfileyes
typed_languageno
bootstrap_filesdocs/Makefile
has_devcontainerno
has_linter_configyes
typecheck_configsmypy.ini, src/mutmut/py.typed
agent_commit_share—
toolchain_manifests—
dependency_bot_commit_share—
Excluded from scoring (no data or not applicable): Demonstrated agent practice, Automated maintenance. Remaining weights renormalized.

Code legibility for models

81Excellent
How it's scored
27/45Type-checkable code — Python with type-check config (mypy.ini, src/mutmut/py.typed)
54.4/55Manageable file sizes — 1/91 source files over 60KB
Inputs used
primary_languagePython
largest_source_bytes72,210
source_files_sampled91
oversized_source_files1

Key facts

1,354GitHub stars
44contributors
127commits, last 12 months
4days since last push
60releases
1bus factor
44open issues
PyPIpackage ecosystems

More detail

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 · 2026-07-21 01:57 UTC

10Binary-Artifactsno binaries found in the repo
0Branch-Protectionbranch protection not enabled on development/release branches
8CI-Tests16 out of 18 merged PRs checked by a CI test -- score normalized to 8
0CII-Best-Practicesno effort to earn an OpenSSF best practices badge detected
4Code-ReviewFound 6/15 approved changesets -- score normalized to 4
10Contributorsproject has 3 contributing companies or organizations -- score normalized to 10
10Dangerous-Workflowno dangerous workflow patterns detected
10Dependency-Update-Toolupdate tool detected
0Fuzzingproject is not fuzzed
10Licenselicense file detected
10Maintained29 commit(s) and 21 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
0Security-Policysecurity policy file not detected
n/aSigned-Releasesno releases found
0Token-Permissionsdetected GitHub workflow tokens with excessive permissions
9Vulnerabilities1 existing vulnerabilities detected
Direct dependencies 7
RegistryPackageVersion constraintManifest
PyPIclick>=8.0.0pyproject.toml
PyPIcoverage>=7.3.0pyproject.toml
PyPIlibcst>=1.8.5pyproject.toml
PyPIpytest>=6.2.5pyproject.toml
PyPIsetproctitle>=1.1.0pyproject.toml
PyPItextual>=1.0.0pyproject.toml
PyPItoml>=0.10.2pyproject.toml
All dependencies 62

Full resolved dependency set from the GitHub dependency graph: 8 direct and 54 indirect (transitive) packages. The transitive closure is complete when the repository commits a lockfile.

RegistryPackageVersionRelation
PyPIclick8.0.0direct
PyPIcoverage7.3.0direct
PyPIlibcst1.8.5direct
PyPIpytest—direct
PyPIpytest9.0.3direct
PyPIsetproctitle1.3.7direct
PyPItextual1.0.0direct
PyPItoml0.10.2direct
PyPIasttokens3.0.1indirect
PyPIbackports-asyncio-runner1.2.0indirect
PyPIbenchmark—indirect
PyPIcfgv3.5.0indirect
PyPIcolorama0.4.6indirect
PyPIconfig0.1.0indirect
PyPIdistlib0.4.0indirect
PyPIexceptiongroup1.2.2indirect
PyPIexceptiongroup1.3.0indirect
PyPIexceptiongroup1.3.1indirect
PyPIexecuting2.2.1indirect
PyPIfilelock3.24.3indirect
PyPIhatchling—indirect
PyPIidentify2.6.16indirect
PyPIiniconfig2.1.0indirect
PyPIiniconfig2.3.0indirect
PyPIinline-snapshot0.32.0indirect
PyPIlibrt0.9.0indirect
PyPIlinkify-it-py2.0.3indirect
PyPImarkdown-it-py4.0.0indirect
PyPImdit-py-plugins0.5.0indirect
PyPImdurl0.1.2indirect
PyPImutmut3.6.0indirect
PyPImy-lib0.1.0indirect
PyPImypy1.20.1indirect
PyPImypy-extensions1.1.0indirect
PyPInodeenv1.10.0indirect
PyPIpackaging24.2indirect
PyPIpackaging25.0indirect
PyPIpackaging26.0indirect
PyPIpathspec1.0.4indirect
PyPIplatformdirs4.5.0indirect
PyPIpluggy1.5.0indirect
PyPIpluggy1.6.0indirect
PyPIpre-commit4.5.1indirect
PyPIpy3-14-features0.1.0indirect
PyPIpygments2.20.0indirect
PyPIpyrefly0.52.0indirect
PyPIpyrefly0.59.1indirect
PyPIpyright1.1.408indirect
PyPIpytest-asyncio1.3.0indirect
PyPIpython-discovery1.1.0indirect
PyPIpyyaml6.0.3indirect
PyPIpyyaml-ft8.0.0indirect
PyPIrich14.2.0indirect
PyPIruff0.15.7indirect
PyPItomli2.2.1indirect
PyPItomli2.3.0indirect
PyPItomli2.4.0indirect
PyPItype-checking0.1.0indirect
PyPItyping-extensions4.15.0indirect
PyPIuc-micro-py1.0.3indirect
PyPIuv-build—indirect
PyPIvirtualenv21.1.0indirect
Dependency advisories 0

Installing pypi:mutmut@3.6.0 pulls in 19 packages, direct and transitive: 0 carry known advisories, of which 0 are direct dependencies.

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

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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 v0.16.0 — full methodology · metrics wiki.

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