# nanopb/nanopb — health index 84/100 (Excellent)

> Inspection of the public repository nanopb/nanopb by inspect.software. It holds a health index of 84 out of 100, placing it in the Excellent band. The index is a signal derived from publicly visible practice, not a warranty, a security audit, or an endorsement, and it is independent of payment.

- Repository: https://github.com/nanopb/nanopb
- Report page: https://inspect.software/software/nanopb/nanopb
- Full JSON report: https://inspect.software/api/repositories/nanopb/nanopb/report
- Badge: https://raw.githubusercontent.com/inspect-software/badges/main/v1/n/nanopb/nanopb.svg
- Inspected: 2026-08-12
- Methodology: metrics 2.10.0, report schema 0.31.0 (https://inspect.software/methodology.md)

## Category summary

| Category | Weight | Index | Band |
|---|---|---|---|
| Vitality | 21% | 60/100 | Moderate |
| Community & Adoption | 17% | 84/100 | Excellent |
| Sustainability & Governance | 23% | 66/100 | Good |
| Engineering Quality | 19% | 76/100 | Good |
| Security | 16% | 74/100 | Good |
| AI Readiness | 4% | 71/100 | Good |

The weighted overall 71 is calibrated to 84 on the published index scale (record calibration 2026-08-02).

## Repository facts

| Field | Value |
|---|---|
| Description | Protocol Buffers with small code size |
| Classification | cli, library |
| Homepage | https://jpa.kapsi.fi/nanopb/ |
| Primary language | C |
| License | Zlib |
| Stars | 5,515 |
| Forks | 1,035 |
| Created | 2015-04-29 |
| Last push | 2026-07-24 |
| Latest release | nanopb-0.4.9.1 |
| Commits (last year) | 34 |
| Bus factor | 1 |
| Topics | nanopb, protocol-buffers, c, embedded, embedded-c |

## Published packages

| Registry | Package | Latest | Monthly downloads |
|---|---|---|---|
| pypi | nanopb | 0.4.9.1 | — |

## Vitality — 60/100 (Moderate)

Is the project alive — is code being written and are releases shipping? Weight: 21% of the overall index.

### Development activity — 62/100 (Moderate)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Push recency | partial | 28.8 / 36 | last push 19 days ago |
| Commit cadence | partial | 9.7 / 36 | 14/52 weeks with commits |
| Commit volume | partial | 13.9 / 18 | 34 commits in the last year |
| OpenSSF Scorecard: Maintained | met | 10 / 10 | 13 commit(s) and 4 issue activity found in the last 90 days -- score normalized to 10 |

### Release discipline — 56/100 (Moderate)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Ships releases | met | 27 / 27 | 1 releases published |
| Release recency | partial | 16.2 / 36 | latest release 363 days ago |
| Release cadence | partial | 12.6 / 27 | cadence unknown (single release) |
| OpenSSF Scorecard: Signed-Releases | not met | 0 / 10 | Project has not signed or included provenance with any releases. |

### Abandonment — 100/100 (Exceptional)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Project is still maintained | met | 100 / 100 | last human commit 37 days ago |

## Community & Adoption — 84/100 (Excellent)

Does the project have users, downloads, attention, and a welcoming setup for contributors? Weight: 17% of the overall index.

### Popularity & adoption — 97/100 (Exceptional)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Stars | met | 60 / 60 | 5,515 stars |
| Forks | met | 25 / 25 | 1,035 forks |
| Watchers | partial | 11.6 / 15 | 122 watchers |

### Community health — 70/100 (Good)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| README | met | 22.5 / 22.5 | — |
| License | met | 22.5 / 22.5 | recognized license (Zlib) |
| CONTRIBUTING guide | met | 18 / 18 | — |
| Code of conduct | not met | 0 / 13.5 | — |
| Issue template | not met | 0 / 7.2 | — |
| PR template | not met | 0 / 6.3 | — |

## Sustainability & Governance — 66/100 (Good)

Will the project survive its people — bus factor, responsiveness, who backs it, and package upkeep? Weight: 23% of the overall index.

### Maintainer resilience (bus factor) — 37/100 (Weak)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Bus factor | partial | 9 / 54 | 1 contributor(s) cover half of all commits |
| Commit distribution | partial | 4.1 / 22.5 | top contributor authored 82% of commits |
| Contributor breadth | met | 13.5 / 13.5 | 99 contributors |
| OpenSSF Scorecard: Contributors | met | 10 / 10 | project has 13 contributing companies or organizations |

### Issue & PR responsiveness — 82/100 (Excellent)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Issue resolution | partial | 38.3 / 42 | 91% of issues closed |
| PR acceptance | partial | 21.6 / 30 | 240/334 decided PRs merged |
| Newcomer PR acceptance | met | 13 / 13 | 1/1 first-time contributors' PRs merged in 30d |
| OpenSSF Scorecard: Code-Review | partial | 9 / 15 | Found 12/20 approved changesets -- score normalized to 6 |

### Ownership & stewardship — 74/100 (Good)

Excluded from scoring (no data or not applicable): Verified domain. Remaining weights renormalized.

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Ownership backing | met | 30 / 30 | organization-owned |
| Verified domain | excluded | 0 / 20 | verified-domain status not read for this organization |
| Owner reach | partial | 12.6 / 25 | 55 followers of nanopb |
| Track record | partial | 16.4 / 25 | 3 public repos, account ~11 yr old |

### Package maintenance — 79/100 (Good)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Published & resolvable | met | 25 / 25 | 1 package(s) on pypi |
| Publish recency | partial | 14 / 35 | latest publish 619 days ago |
| Version history | met | 20 / 20 | 176 published versions |
| Not deprecated | met | 20 / 20 | active, not deprecated or yanked |

## Engineering Quality — 76/100 (Good)

Are baseline engineering and documentation practices in place? Weight: 19% of the overall index.

### Engineering practices — 66/100 (Good)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| CI workflows | met | 24 / 24 | 15 workflow(s) |
| Tests present | met | 24 / 24 | — |
| Linter config | not met | 0 / 16 | — |
| Pre-commit hooks | not met | 0 / 9.6 | — |
| .editorconfig | not met | 0 / 6.4 | — |
| OpenSSF Scorecard: CI-Tests | partial | 18 / 20 | 13 out of 14 merged PRs checked by a CI test -- score normalized to 9 |

### Documentation — 90/100 (Excellent)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| README | met | 30 / 30 | — |
| Documentation directory | met | 25 / 25 | — |
| Documentation / homepage site | met | 15 / 15 | https://jpa.kapsi.fi/nanopb/ |
| Repository description | met | 10 / 10 | — |
| Topics | met | 10 / 10 | 5 topics |
| Wiki | not met | 0 / 10 | — |

## Security — 74/100 (Good)

Are visible security and supply-chain practices strong, with no malicious dependency and no unresolved high-risk jurisdiction exposure? Weight: 16% of the overall index.

### Security posture — 68/100 (Good)

Excluded from scoring (no data or not applicable): Branch-Protection, Packaging. Remaining weights renormalized.

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Binary-Artifacts | met | 7.5 / 7.5 | no binaries found in the repo |
| Branch-Protection | excluded | 0 / 7.5 | internal 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 |
| CI-Tests | partial | 2.2 / 2.5 | 13 out of 14 merged PRs checked by a CI test -- score normalized to 9 |
| CII-Best-Practices | not met | 0 / 2.5 | no effort to earn an OpenSSF best practices badge detected |
| Code-Review | partial | 4.5 / 7.5 | Found 12/20 approved changesets -- score normalized to 6 |
| Contributors | met | 2.5 / 2.5 | project has 13 contributing companies or organizations |
| Dangerous-Workflow | met | 10 / 10 | no dangerous workflow patterns detected |
| Dependency-Update-Tool | met | 7.5 / 7.5 | update tool detected |
| Fuzzing | met | 5 / 5 | project is fuzzed |
| License | met | 2.5 / 2.5 | license file detected |
| Maintained | met | 7.5 / 7.5 | 13 commit(s) and 4 issue activity found in the last 90 days -- score normalized to 10 |
| Packaging | excluded | 0 / 5 | packaging workflow not detected |
| Pinned-Dependencies | not met | 0 / 5 | dependency not pinned by hash detected -- score normalized to 0 |
| SAST | met | 5 / 5 | SAST tool is run on all commits |
| Security-Policy | partial | 2 / 5 | security policy file detected |
| Signed-Releases | not met | 0 / 7.5 | Project has not signed or included provenance with any releases. |
| Token-Permissions | not met | 0 / 7.5 | detected GitHub workflow tokens with excessive permissions |
| Vulnerabilities | partial | 6.8 / 7.5 | 1 existing vulnerabilities detected |

### Dependency advisories — 100/100 (Exceptional)

Excluded from scoring (no data or not applicable): No advisories left outstanding. Remaining weights renormalized. Matched the pypi:nanopb@0.4.9.1 runtime dependency closure — what installing the published package pulls in — 1 packages. Reachability is not analyzed.

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Direct dependencies free of known advisories | met | 35 / 35 | no direct dependency carries a known advisory |
| Indirect dependencies free of known advisories | met | 25 / 25 | no indirect dependency carries a known advisory |
| No advisories left outstanding | excluded | 0 / 40 | no advisory carries a publication date |

### Malicious dependencies — 100/100 (Exceptional)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| No dependency reported as a malicious package | met | 100 / 100 | no dependency is reported as a malicious package |

### High-Risk Jurisdiction Exposure — 100/100 (Exceptional)

Only high-confidence self-published location evidence affects this multiplier. Ambiguous matches are review-only; country evidence is not proof of nationality, citizenship, legal registration, malicious intent, or sanctions status.

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Policy exposure multiplier | met | 100 / 100 | no confirmed policy-scope location match |

## AI Readiness — 71/100 (Good)

How well is the repo equipped to be developed and maintained with AI coding agents? Carries a deliberately small weight: agent tooling is a real maintenance signal, but its absence must never gate the top of the scale (calibration saturates at raw 91, so 100/100 remains reachable with AI Readiness at zero).

### Agent context & guidance — 31/100 (At Risk)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Agent instructions | not met | 0 / 45 | no CLAUDE.md / AGENTS.md / editor rules |
| Machine-readable docs (llms.txt) | not met | 0 / 15 | — |
| Legible commit history | partial | 31.3 / 40 | 57 of 97 human commits state their intent (structured subject or explanatory body) |

### Verify loop (build / test / typecheck) — 79/100 (Good)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| One-command bootstrap | met | 18 / 18 | docs/Makefile, examples/network_server/Makefile, examples/simple/Makefile, examples/using_union_messages/Makefile, generator/proto/Makefile, tests/Makefile |
| Automated tests | met | 22 / 22 | — |
| Lint / format config | not met | 0 / 11 | — |
| Static type checking | met | 11 / 11 | C (statically typed) |
| Reproducible environment | met | 10 / 10 | Dockerfile |
| Demonstrated agent practice | met | 10 / 10 | 5 of the last 100 commits agent-authored or agent-credited |
| Automated maintenance | met | 8 / 8 | 3 of the last 100 commits are automated dependency updates |
| OpenSSF Scorecard: Pinned-Dependencies | not met | 0 / 10 | dependency not pinned by hash detected -- score normalized to 0 |

### Code legibility for models — 100/100 (Exceptional)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Type-checkable code | met | 45 / 45 | C (statically typed) |
| Manageable file sizes | partial | 54.7 / 55 | 1/194 source files over 60KB |

### Machine-readable interfaces — 100/100 (Exceptional)

Excluded from scoring (no data or not applicable): MCP server. Remaining weights renormalized.

| Criterion | Status | Points | Detail |
|---|---|---|---|
| API schema (OpenAPI/GraphQL/proto) | met | 40 / 40 | build-tests/cmake_with_components/simple.proto, build-tests/legacy_cmake_relpath/proto/simple.proto, build-tests/legacy_cmake_relpath/proto/sub/unlucky.proto, build-tests/legacy_cmake_simple/simple.proto, examples/cmake_relpath/proto/simple.proto, examples/cmake_relpath/proto/sub/unlucky.proto, examples/cmake_simple/simple.proto, examples/conan_dependency/protos/simple.proto, examples/meson_simple/simple.proto, examples/network_server/fileproto.proto, examples/platformio/proto/pio_with_options.proto, examples/platformio/proto/pio_without_options.proto, examples/simple/simple.proto, examples/using_union_messages/unionproto.proto, generator/proto/google/protobuf/descriptor.proto, generator/proto/nanopb.proto, tests/alltypes/alltypes.proto, tests/alltypes_proto3/alltypes.proto, tests/anonymous_oneof/oneof.proto, tests/any_type/anytest.proto, tests/any_type/google/protobuf/any.proto, tests/any_type/google/protobuf/duration.proto, tests/backwards_compatibility/alltypes_legacy.proto, tests/callbacks/callbacks.proto, tests/comments/comments.proto, tests/common/person.proto, tests/common/unittestproto.proto, tests/cxx_callback_datatype/message.proto, tests/cxx_descriptor/message.proto, tests/cyclic_messages/cyclic.proto, tests/deep_structure/deep.proto, tests/descriptor_proto/descriptor.proto, tests/editions/edition_2024.proto, tests/enum_mapping/enum_mapping.proto, tests/enum_minmax/enumminmax.proto, tests/enum_sizes/enum_intsize.proto, tests/enum_sizes/packed_enum.proto, tests/enum_to_string/enum.proto, tests/enum_validate/enum.proto, tests/extensions/extensions.proto, tests/fallback_type/fallback_type.proto, tests/field_size_16/alltypes.proto, tests/field_size_16_proto3/alltypes.proto, tests/field_size_32/alltypes.proto, tests/fixed_count/fixed_count.proto, tests/float_double_conversion/doublemsg.proto, tests/generator_relative_paths/proto/protobuf/any.proto, tests/generator_relative_paths/proto/simple.proto, tests/generator_relative_paths/test.proto, tests/infinity_nan/floats.proto, tests/initializers/initializertest.proto, tests/inline/inline.proto, tests/intsizes/intsizes.proto, tests/map/map.proto, tests/mem_release/mem_release.proto, tests/message_sizes/messages1.proto, tests/message_sizes/messages2.proto, tests/missing_fields/missing_fields.proto, tests/msgid/msgid_example.proto, tests/multiple_files/multifile1.proto, tests/multiple_files/multifile2.proto, tests/multiple_files/subdir/multifile2.proto, tests/namingstyle/naming_style.proto, tests/namingstyle_custom/custom_naming_style.proto, tests/namingstyle_custom/custom_naming_style_importer.proto, tests/namingstyle_custom/custom_naming_style_mangle.proto, tests/namingstyle_custom/custom_naming_style_other.proto, tests/namingstyle_custom/custom_naming_style_package.proto, tests/no_messages/no_messages.proto, tests/oneof/oneof.proto, tests/oneof_callback/oneof.proto, tests/options/options.proto, tests/options/proto3_options.proto, tests/proto3_optional/optional.proto, tests/recursive_proto/recursive.proto, tests/regression/GHSA-gcx3-7m76-287p/test.proto, tests/regression/issue_1017/test.proto, tests/regression/issue_1061/submsg_ft_callback.proto, tests/regression/issue_1131/package_name_prefix.proto, tests/regression/issue_118/enumdef.proto, tests/regression/issue_118/enumuse.proto, tests/regression/issue_125/extensionbug.proto, tests/regression/issue_141/testproto.proto, tests/regression/issue_145/comments.proto, tests/regression/issue_166/enums.proto, tests/regression/issue_172/submessage/submessage.proto, tests/regression/issue_172/test.proto, tests/regression/issue_188/oneof.proto, tests/regression/issue_195/test.proto, tests/regression/issue_203/file1.proto, tests/regression/issue_203/file2.proto, tests/regression/issue_205/size_corruption.proto, tests/regression/issue_227/unaligned_uint64.proto, tests/regression/issue_229/multiple_oneof.proto, tests/regression/issue_242/zero_value.proto, tests/regression/issue_247/padding.proto, tests/regression/issue_249/test.proto, tests/regression/issue_253/short_array.proto, tests/regression/issue_256/submsg_array.proto, tests/regression/issue_259/callback_pointer.proto, tests/regression/issue_306/large_extension.proto, tests/regression/issue_322/defaults.proto, tests/regression/issue_338/bigvalue.proto, tests/regression/issue_342/extensions.proto, tests/regression/issue_363/oneofmsg.proto, tests/regression/issue_376/fixed_array.proto, tests/regression/issue_380/manglenames.proto, tests/regression/issue_395/test.proto, tests/regression/issue_407/extensions.proto, tests/regression/issue_453/test.proto, tests/regression/issue_472/test.proto, tests/regression/issue_487/test.proto, tests/regression/issue_493/test.proto, tests/regression/issue_494/oneof.proto, tests/regression/issue_494/submessage.proto, tests/regression/issue_504/test.proto, tests/regression/issue_522/uenum.proto, tests/regression/issue_524/oneof.proto, tests/regression/issue_524/submessage.proto, tests/regression/issue_535/issue_535.proto, tests/regression/issue_544/submsg_callback.proto, tests/regression/issue_545/submsg_callback.proto, tests/regression/issue_547/test.proto, tests/regression/issue_558/mixed.proto, tests/regression/issue_569/a.proto, tests/regression/issue_569/b.proto, tests/regression/issue_610/DataPacket.proto, tests/regression/issue_610/LogMessage.proto, tests/regression/issue_610/nanopb_generator_bug/first.proto, tests/regression/issue_610/nanopb_generator_bug/first/a.proto, tests/regression/issue_610/nanopb_generator_bug/first/a/aa.proto, tests/regression/issue_610/nanopb_generator_bug/first/a/ab.proto, tests/regression/issue_610/nanopb_generator_bug/first/b.proto, tests/regression/issue_610/nanopb_generator_bug/first/b/ba.proto, tests/regression/issue_611/uenum.proto, tests/regression/issue_617/oneof.proto, tests/regression/issue_631/submsg_callback.proto, tests/regression/issue_637/oneof.proto, tests/regression/issue_637/other.proto, tests/regression/issue_644/int64.proto, tests/regression/issue_647/repro.proto, tests/regression/issue_692/oneof.proto, tests/regression/issue_692/other.proto, tests/regression/issue_746/test.proto, tests/regression/issue_783/folder_A/file_A.proto, tests/regression/issue_783/folder_B/file_B.proto, tests/regression/issue_783/folder_C/file_C.proto, tests/regression/issue_795/test.proto, tests/regression/issue_795/test2.proto, tests/regression/issue_795/test3.proto, tests/regression/issue_838/enum.proto, tests/regression/issue_869/bigfile.proto, tests/regression/issue_956/skipmap.proto, tests/reserved_keywords/reserved_keywords.proto, tests/sort_by_tag/sort_by_tag.proto, tests/special_characters/funny-proto+name has.characters.proto, tests/stackusage/stackusage.proto, tests/typename_mangling/with_package.proto, tests/typename_mangling/with_package_a.proto, tests/typename_mangling/with_package_b.proto, tests/without_64bit/alltypes.proto |
| MCP server | excluded | 0 / 20 | not applicable to this kind of software |
| Runnable examples | met | 40 / 40 | examples |

## Collection warnings

- Star history unavailable: GitHub GraphQL error: Resource not accessible by personal access token

## What this report is

inspect.software measures public repositories against a single published, versioned methodology and reports the result as a 1–100 health index. Findings are signals derived from what is visible in public repository data — they are not a security audit, a warranty, or an endorsement, and no result depends on payment.

- Methodology, formulas and weights: https://inspect.software/methodology.md
- What a result does and does not claim: https://inspect.software/wiki/signals-not-warranties.md
- Rating bands: https://inspect.software/wiki/scoring-bands.md
- Corrections: https://inspect.software/contact.md
- Index of all documents: https://inspect.software/llms.txt