Public record
Software health reportschema 0.34.0 · metrics 2.10.0 · 2026-09-20 06:07 UTC

kovidgoyal / calibre

The official source code repository for the calibre ebook manager

Python · CGPL-3.0★ 25,953 stars⑂ 2,697 forkssince May 2013View on GitHub ↗
KindDesktop applicationCommand-line toolhow this is determined

kovidgoyal/calibre holds a health index of 87 out of 100, placing it in the Excellent band. It scores highest on Vitality (96/100) and lowest on AI Readiness (45/100). It was last updated today. A single contributor accounts for most of its recent work.

87
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.

87
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 73 is calibrated to 87 on the published index scale (record calibration 2026-08-02).

Ownership

Kovid GoyalPersonal account
5,725 followers45 public repossince Jan 2012

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 publish
PyPIcalibrepoints to another repo — not scored0.13.02,318723 days ago

Metrics by category

Vitality

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

96Exceptional · 21% of overall

Development activity

100Exceptional
How it's scored
36/36Push recencylast push 0 days ago
36/36Commit cadence52/52 weeks with commits
18/18Commit volume2,604 commits in the last year
10/10OpenSSF Scorecard: Maintained30 commit(s) and 0 issue activity found in the last 90 days -- score normalized to 10
Inputs used
commits_last_year2,604
human_commit_share0.99
days_since_last_push0
active_weeks_last_year52
How it's scored
27/27Ships releases100 releases published
36/36Release recencylatest release 2 days ago
27/27Release cadencea release every ~19.4 days
0/10OpenSSF Scorecard: Signed-ReleasesProject has not signed or included provenance with any releases.
Inputs used
releases_count100
latest_release_tagv9.15.0
releases_from_tagsno
days_since_latest_release2
mean_days_between_releases19.4

Community & Adoption

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

76Good · 17% of overall
How it's scored
60/60Stars25,953 stars
25/25Forks2,697 forks
14.4/15Watchers384 watchers
Inputs used
forks2,697
stars25,953
watchers384
growth_stateunverified
growth_factor_pct100
growth_unverified_reasonno_history
How it's scored
22.5/22.5README
22.5/22.5Licenserecognized license (GPL-3.0)
0/18CONTRIBUTING guide
0/13.5Code of conduct
0/7.2Issue template
0/6.3PR template
Inputs used
has_readmeyes
has_licenseyes
readme_badges1
has_contributingno
has_issue_templateno
has_code_of_conductno
readme_badge_servicesgithub.com
has_pull_request_templateno

Sustainability & Governance

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

57Moderate · 23% of overall
How it's scored
9/54Bus factor1 contributor(s) cover half of all commits
3.7/22.5Commit distributiontop contributor authored 84% of commits
13.5/13.5Contributor breadth98 contributors
10/10OpenSSF Scorecard: Contributorsproject has 17 contributing companies or organizations
Inputs used
bus_factor1
contributors_sampled98
top_contributor_share0.835
How it's scored
0/42Issue resolutionno issues or no data
25.9/30PR acceptance2,816/3,264 decided PRs merged
8.7/13Newcomer PR acceptance6/9 first-time contributors' PRs merged in 30d
3/15OpenSSF Scorecard: Code-ReviewFound 5/23 approved changesets -- score normalized to 2
Inputs used
merged_prs2,816
open_issues0
closed_issues0
prs_merged_7d11
prs_decided_7d14
prs_merged_30d15
prs_decided_30d22
issue_closed_ratio
closed_unmerged_prs448
first_time_authors_30d8
first_time_prs_merged_30d6
first_time_prs_decided_30d9
Excluded from scoring (no data or not applicable): Issue resolution. Remaining weights renormalized.
How it's scored
10/30Ownership backingpersonal (user) account
0/20Verified domainnot applicable to user accounts
25/25Owner reach5,725 followers of kovidgoyal
24.1/25Track record45 public repos, account ~14 yr old
Inputs used
followers5,725
owner_typeUser
is_verified
owner_loginkovidgoyal
public_repos45
account_age_days5,371
Excluded from scoring (no data or not applicable): Verified domain. Remaining weights renormalized.

Engineering Quality

Are baseline engineering and documentation practices in place?

70Good · 19% of overall
How it's scored
24/24CI workflows4 workflow(s)
24/24Tests present
16/16Linter configpyproject.toml ([tool.ruff])
0/9.6Pre-commit hooks
0/6.4.editorconfig
10/20OpenSSF Scorecard: CI-Tests3 out of 6 merged PRs checked by a CI test -- score normalized to 5
Inputs used
has_ciyes
has_testsyes
has_editorconfigno
has_linter_configyes
has_precommit_configno
How it's scored
30/30README
0/25Documentation directory
15/15Documentation / homepage sitehttps://calibre-ebook.com
10/10Repository description
10/10Topics10 topics
0/10Wiki
Inputs used
topicsebook-manager, calibre, python, ebook, ebooks, ebook-reader, ebook-formats, epub, kindle, epub-generation
has_wikino
homepagehttps://calibre-ebook.com
docs_sitehttps://calibre-ebook.com
has_readmeyes
has_docs_dirno
has_descriptionyes

Security

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

73Good · 16% of overall
How it's scored
7.5/7.5Binary-Artifactsno binaries found in the repo
2.2/7.5Branch-Protectionbranch protection is not maximal on development and all release branches
1.2/2.5CI-Tests3 out of 6 merged PRs checked by a CI test -- score normalized to 5
0/2.5CII-Best-Practicesno effort to earn an OpenSSF best practices badge detected
1.5/7.5Code-ReviewFound 5/23 approved changesets -- score normalized to 2
2.5/2.5Contributorsproject has 17 contributing companies or organizations
10/10Dangerous-Workflowno dangerous workflow patterns detected
7.5/7.5Dependency-Update-Toolupdate tool detected
0/5Fuzzingproject is not fuzzed
2.5/2.5Licenselicense file detected
7.5/7.5Maintained30 commit(s) and 0 issue activity found in the last 90 days -- score normalized to 10
0/5Packagingno data
0/5Pinned-Dependenciesdependency not pinned by hash detected -- score normalized to 0
4/5SASTSAST tool detected but not run on all commits
5/5Security-Policysecurity policy file detected
0/7.5Signed-ReleasesProject has not signed or included provenance with any releases.
7.5/7.5Token-PermissionsGitHub workflow tokens follow principle of least privilege
7.5/7.5Vulnerabilities0 existing vulnerabilities detected
Inputs used
sourceopenssf_scorecard
checks_evaluated17
scorecard_versionv5.5.0
checks_inconclusive1
scorecard_aggregate6.7
Excluded from scoring (no data or not applicable): Packaging. Remaining weights renormalized.

Dependency advisories

100Exceptional
How it's scored
35/35Direct dependencies free of known advisoriesno direct dependency carries a known advisory
25/25Indirect dependencies free of known advisoriesno indirect dependency carries a known advisory
0/40No advisories left outstandingno advisory carries a publication date
Inputs used
sourceosv
advisories0
affected_packages0
assessed_packages7
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:calibre@0.13.0 runtime dependency closure — what installing the published package pulls in — 7 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.

45Weak · 4% of overall
How it's scored
0/45Agent instructionsno CLAUDE.md / AGENTS.md / editor rules
0/15Machine-readable docs (llms.txt)
11.3/40Legible commit history21 of 99 human commits state their intent (structured subject or explanatory body)
Inputs used
has_llms_txtno
llms_txt_url
legible_history_share0.212
agent_instruction_files
agent_instruction_max_bytes
How it's scored
0/18One-command bootstrap
22/22Automated tests
11/11Lint / format configpyproject.toml ([tool.ruff])
0/11Static type checking
0/10Reproducible environment
6/10Demonstrated agent practice3 of the last 100 commits agent-authored or agent-credited
8/8Automated maintenance1 of the last 100 commits are automated dependency updates
0/10OpenSSF Scorecard: Pinned-Dependenciesdependency not pinned by hash detected -- score normalized to 0
Inputs used
has_nixno
has_testsyes
lockfiles
has_dockerfileno
typed_languageno
bootstrap_files
has_devcontainerno
has_linter_configyes
typecheck_configs
agent_commit_share0.03
toolchain_manifests
dependency_bot_commit_share0.01
How it's scored
0/45Type-checkable codePython without a type-check config
53/55Manageable file sizes63/1,697 source files over 60KB
Inputs used
primary_languagePython
largest_source_bytes5,169,143
source_files_sampled1,697
oversized_source_files63
How it's scored
0/40API schema (OpenAPI/GraphQL/proto)not applicable to this kind of software
0/20MCP servernot applicable to this kind of software
40/40Runnable examplesrecipes
Inputs used
example_dirsrecipes
has_mcp_signalno
api_schema_files
interfaces_expected_of
Excluded from scoring (no data or not applicable): API schema (OpenAPI/GraphQL/proto), MCP server. Remaining weights renormalized.

Key facts

25,953GitHub stars
98contributors
2,604commits, last 12 months
0days since last push
100releases
1bus factor
0open issues
PyPIpackage ecosystems

Data collection warnings

  • Star history unavailable: GitHub GraphQL error: Resource not accessible by personal access token
  • First-time contributor figures cover 12 of 19 authors (cap 12)
  • pypi package 'calibre' points at a different repository (https://github.com/finite-sample/calibre); excluded from ecosystem scoring

More detail

Star and fork history 0 ★ / 2,697 ⇿
0Stars
2,697Forks
91Releases

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.

Only the most recent history is shown — this repository exceeds the collection window, so the earliest history is not captured.

1,5001,7502,0002,2502,5002,7502,697192023-022024-122026-09
Major 3Minor 73Patch 15

Each point covers 4 days.

OpenSSF Scorecard 6.7 / 10
6.7aggregate

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 · 2026-09-20 06:07 UTC

10Binary-Artifactsno binaries found in the repo
3Branch-Protectionbranch protection is not maximal on development and all release branches
5CI-Tests3 out of 6 merged PRs checked by a CI test -- score normalized to 5
0CII-Best-Practicesno effort to earn an OpenSSF best practices badge detected
2Code-ReviewFound 5/23 approved changesets -- score normalized to 2
10Contributorsproject has 17 contributing companies or organizations
10Dangerous-Workflowno dangerous workflow patterns detected
10Dependency-Update-Toolupdate tool detected
0Fuzzingproject is not fuzzed
10Licenselicense file detected
10Maintained30 commit(s) and 0 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
8SASTSAST tool detected but not run on all commits
10Security-Policysecurity policy file detected
0Signed-ReleasesProject has not signed or included provenance with any releases.
10Token-PermissionsGitHub workflow tokens follow principle of least privilege
10Vulnerabilities0 existing vulnerabilities detected
Direct dependencies 54
RegistryPackageVersion constraintManifest
PyPIsix== 1.17.0pyproject.toml
PyPIunrardll== 0.1.7pyproject.toml
PyPIlxml== 6.1.1pyproject.toml
PyPIpychm== 0.8.6pyproject.toml
PyPIhtml5-parser== 0.5.0pyproject.toml
PyPIcss-parser== 1.1.1pyproject.toml
PyPIpython-dateutil== 2.9.0pyproject.toml
PyPIjeepney== 0.9.0pyproject.toml
PyPIdnspython== 2.8.0pyproject.toml
PyPImechanize== 0.4.10pyproject.toml
PyPIfeedparser-sgmllib== 2.0.1pyproject.toml
PyPIfeedparser== 6.0.14pyproject.toml
PyPIMarkdown== 3.10.0pyproject.toml
PyPIhtml2text== 2025.4.15pyproject.toml
PyPIsoupsieve== 2.9pyproject.toml
PyPItyping-extensions== 4.15.0pyproject.toml
PyPIbeautifulsoup4== 4.14.3pyproject.toml
PyPIregex== 2025.11.3pyproject.toml
PyPIchardet== 5.2.0pyproject.toml
PyPImsgpack== 1.2.1pyproject.toml
PyPIPygments== 2.20.0pyproject.toml
PyPIpycryptodome== 3.23.0pyproject.toml
PyPIapsw== 3.53.2.0pyproject.toml
PyPIwebencodings== 0.5.1pyproject.toml
PyPIhtml5lib== 1.1pyproject.toml
PyPIpillow== 12.3.0pyproject.toml
PyPInetifaces== 0.11.0pyproject.toml
PyPIpsutil== 7.1.3pyproject.toml
PyPIifaddr== 0.2.0pyproject.toml
PyPItexttable== 1.7.0pyproject.toml
PyPImultivolumefile== 0.2.3pyproject.toml
PyPIBrotli== 1.2.0pyproject.toml
PyPIpyppmd== 1.3.1pyproject.toml
PyPIpybcj== 1.0.7pyproject.toml
PyPIinflate64== 1.0.4pyproject.toml
PyPIpy7zr== 1.1.3pyproject.toml
PyPIjaconv== 0.4.1pyproject.toml
PyPIwrapt== 2.0.1pyproject.toml
PyPIDeprecated== 1.3.1pyproject.toml
PyPIpykakasi== 2.3.0pyproject.toml
PyPIzeroconf== 0.149.16pyproject.toml
PyPIfonttools== 4.61.0pyproject.toml
PyPIlxml_html_clean== 0.4.5pyproject.toml
PyPIPyQt6_sip== 13.10.2pyproject.toml
PyPIPyQt6== 6.10.0pyproject.toml
PyPIPyQt6_WebEngine== 6.10.0pyproject.toml
PyPIMacFSEvents== 0.8.4pyproject.toml
PyPIxxhash== 3.6.0pyproject.toml
PyPItzdata== 2026.4pyproject.toml
PyPItzlocal== 5.4.4pyproject.toml
PyPIpystache== 0.6.8pyproject.toml
PyPIapify_fingerprint_datapoints== 0.15.0pyproject.toml
PyPIclick== 8.5.0pyproject.toml
PyPIbrowserforge== 1.2.4pyproject.toml
All dependencies 72

Full resolved dependency set from the GitHub dependency graph: 54 direct and 18 indirect (transitive) packages. The transitive closure is complete when the repository commits a lockfile.

RegistryPackageVersionRelation
PyPIapify-fingerprint-datapoints0.15.0direct
PyPIapsw3.53.2.0direct
PyPIbeautifulsoup44.14.3direct
PyPIbrotli1.2.0direct
PyPIbrowserforge1.2.4direct
PyPIchardet5.2.0direct
PyPIclick8.5.0direct
PyPIcss-parser1.1.1direct
PyPIdeprecated1.3.1direct
PyPIdnspython2.8.0direct
PyPIfeedparser6.0.14direct
PyPIfeedparser-sgmllib2.0.1direct
PyPIfonttools4.61.0direct
PyPIhtml2text2025.4.15direct
PyPIhtml5-parser0.5.0direct
PyPIhtml5lib1.1direct
PyPIifaddr0.2.0direct
PyPIinflate641.0.4direct
PyPIjaconv0.4.1direct
PyPIjeepney0.9.0direct
PyPIlxml6.1.1direct
PyPIlxml-html-clean0.4.5direct
PyPImacfsevents0.8.4direct
PyPImarkdown3.10.0direct
PyPImechanize0.4.10direct
PyPImsgpack1.2.1direct
PyPImultivolumefile0.2.3direct
PyPInetifaces0.11.0direct
PyPIpillow12.3.0direct
PyPIpsutil7.1.3direct
PyPIpy7zr1.1.3direct
PyPIpybcj1.0.7direct
PyPIpychm0.8.6direct
PyPIpycryptodome3.23.0direct
PyPIpygments2.20.0direct
PyPIpykakasi2.3.0direct
PyPIpyppmd1.3.1direct
PyPIpyqt66.10.0direct
PyPIpyqt6-sip13.10.2direct
PyPIpyqt6-webengine6.10.0direct
PyPIpystache0.6.8direct
PyPIpython-dateutil2.9.0direct
PyPIregex2025.11.3direct
PyPIsix1.17.0direct
PyPIsoupsieve2.9direct
PyPItexttable1.7.0direct
PyPItyping-extensions4.15.0direct
PyPItzdata2026.4direct
PyPItzlocal5.4.4direct
PyPIunrardll0.1.7direct
PyPIwebencodings0.5.1direct
PyPIwrapt2.0.1direct
PyPIxxhash3.6.0direct
PyPIzeroconf0.149.16direct
PyPIbuild1.3.0indirect
PyPIclang-formatindirect
PyPIinstaller0.7.0indirect
PyPIpackaging25.0indirect
PyPIpkgconfig1.5.5indirect
PyPIply3.11indirect
PyPIpoetry-core2.2.1indirect
PyPIpybind113.0.1indirect
PyPIpyproject-hooks1.2.0indirect
PyPIpyqt-builder1.19.1indirect
PyPIrapydscript-ngindirect
PyPIruffindirect
PyPIsetuptools83.0.0indirect
PyPIsetuptools-scm9.2.2indirect
PyPIsip6.14.0indirect
PyPItyindirect
PyPItypes-lxmlindirect
PyPIwheel0.46.2indirect
Dependency advisories 0

Installing pypi:calibre@0.13.0 pulls in 7 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

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.

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 statisticsPyPI.