# endojs/endo — health index 98/100 (Exceptional)

> Inspection of the public repository endojs/endo by inspect.software. It holds a health index of 98 out of 100, placing it in the Exceptional 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/endojs/endo
- Report page: https://inspect.software/software/endojs/endo
- Full JSON report: https://inspect.software/api/repositories/endojs/endo/report
- Badge: https://raw.githubusercontent.com/inspect-software/badges/main/v1/e/endojs/endo.svg
- Inspected: 2026-09-15
- Methodology: metrics 2.10.0, report schema 0.34.0 (https://inspect.software/methodology.md)

## Category summary

| Category | Weight | Index | Band |
|---|---|---|---|
| Vitality | 21% | 99/100 | Exceptional |
| Community & Adoption | 17% | 79/100 | Good |
| Sustainability & Governance | 23% | 78/100 | Good |
| Engineering Quality | 19% | 90/100 | Excellent |
| Security | 16% | 82/100 | Excellent |
| AI Readiness | 4% | 89/100 | Excellent |

The weighted overall 86 is calibrated to 98 on the published index scale (record calibration 2026-08-02).

## Repository facts

| Field | Value |
|---|---|
| Description | Endo is a distributed secure JavaScript sandbox, based on SES |
| Classification | cli, library |
| Homepage | https://endojs.org/ |
| Primary language | JavaScript |
| License | Apache-2.0 |
| Stars | 1,057 |
| Forks | 91 |
| Created | 2019-11-06 |
| Last push | 2026-09-15 |
| Latest release | @endo/pass-style@2.0.1 |
| Commits (last year) | 778 |
| Bus factor | 3 |
| Topics | capabilities, captp, hardened, javascript, multi-tenant, ocaps, powerbox, prototype-pollution, security, supply-chain, sandbox |

## Published packages

| Registry | Package | Latest | Monthly downloads |
|---|---|---|---|
| npm | @endo/exo | 1.7.0 | 36,842 |
| npm | @endo/far | 1.1.14 | 57,678 |
| npm | @endo/bytes | 1.0.2 | 223 |
| npm | @endo/captp | 4.5.1 | 27,621 |
| npm | @endo/base64 | 1.1.1 | 48,942 |
| npm | @endo/common | 1.4.0 | 34,088 |
| npm | @endo/errors | 1.3.1 | 37,463 |
| npm | @endo/chacha12 | 1.0.0 | 21 |
| npm | @endo/cli | 1.0.3 | 46 |
| npm | @endo/daemon | 1.0.3 | 29 |

## Vitality — 99/100 (Exceptional)

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

### Development activity — 99/100 (Exceptional)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Push recency | met | 36 / 36 | last push 0 days ago |
| Commit cadence | partial | 34.6 / 36 | 50/52 weeks with commits |
| Commit volume | met | 18 / 18 | 778 commits in the last year |
| OpenSSF Scorecard: Maintained | met | 10 / 10 | 30 commit(s) and 12 issue activity found in the last 90 days -- score normalized to 10 |

### Release discipline — 100/100 (Exceptional)

Excluded from scoring (no data or not applicable): OpenSSF Scorecard: Signed-Releases. Remaining weights renormalized.

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Ships releases | met | 27 / 27 | 100 releases published |
| Release recency | met | 36 / 36 | latest release 28 days ago |
| Release cadence | met | 27 / 27 | a release every ~0.4 days |
| OpenSSF Scorecard: Signed-Releases | excluded | 0 / 10 | no releases found |

### Abandonment — 100/100 (Exceptional)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Project is still maintained | met | 100 / 100 | last human commit 5 days ago |

## Community & Adoption — 79/100 (Good)

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

### Popularity & adoption — 73/100 (Good)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Stars | partial | 49 / 60 | 1,057 stars |
| Forks | partial | 16.3 / 25 | 91 forks |
| Watchers | partial | 7.8 / 15 | 26 watchers |

### Community health — 77/100 (Good)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| README | met | 22.5 / 22.5 | — |
| License | met | 22.5 / 22.5 | recognized license (Apache-2.0) |
| CONTRIBUTING guide | met | 18 / 18 | — |
| Code of conduct | not met | 0 / 13.5 | — |
| Issue template | not met | 0 / 7.2 | — |
| PR template | met | 6.3 / 6.3 | — |

### Ecosystem adoption (downloads) — 90/100 (Excellent)

Excluded from scoring (no data or not applicable): Registry dependents. Remaining weights renormalized.

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Monthly downloads | partial | 71.8 / 80 | 242,953 downloads/month across npm |
| Registry dependents | excluded | 0 / 20 | not reported by this ecosystem |

## Sustainability & Governance — 78/100 (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) — 75/100 (Good)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Bus factor | partial | 36 / 54 | 3 contributor(s) cover half of all commits |
| Commit distribution | partial | 15.5 / 22.5 | top contributor authored 31% of commits |
| Contributor breadth | met | 13.5 / 13.5 | 48 contributors |
| OpenSSF Scorecard: Contributors | met | 10 / 10 | project has 55 contributing companies or organizations |

### Issue & PR responsiveness — 79/100 (Good)

Excluded from scoring (no data or not applicable): Newcomer PR acceptance. Remaining weights renormalized.

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Issue resolution | partial | 29.1 / 42 | 69% of issues closed |
| PR acceptance | partial | 24.6 / 30 | 1673/2044 decided PRs merged |
| Newcomer PR acceptance | excluded | 0 / 13 | no first-time contributor's PR decided in 30d |
| OpenSSF Scorecard: Code-Review | met | 15 / 15 | all changesets reviewed |

### Ownership & stewardship — 63/100 (Moderate)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Ownership backing | met | 30 / 30 | organization-owned |
| Verified domain | not met | 0 / 20 | — |
| Owner reach | partial | 12 / 25 | 45 followers of endojs |
| Track record | partial | 21.1 / 25 | 17 public repos, account ~11 yr old |

### Package maintenance — 100/100 (Exceptional)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Published & resolvable | met | 25 / 25 | 10 package(s) on npm |
| Publish recency | met | 35 / 35 | latest publish 32 days ago |
| Version history | met | 20 / 20 | 52 published versions |
| Not deprecated | met | 20 / 20 | active, not deprecated or yanked |

## Engineering Quality — 90/100 (Excellent)

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

### Engineering practices — 84/100 (Excellent)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| CI workflows | met | 24 / 24 | 10 workflow(s) |
| Tests present | met | 24 / 24 | — |
| Linter config | met | 16 / 16 | .eslintrc.json, eslint.config.js, package.json ("prettier"), packages/compartment-mapper/package.json ("prettier") |
| Pre-commit hooks | not met | 0 / 9.6 | — |
| .editorconfig | not met | 0 / 6.4 | — |
| OpenSSF Scorecard: CI-Tests | met | 20 / 20 | 22 out of 22 merged PRs checked by a CI test -- score normalized to 10 |

### Documentation — 100/100 (Exceptional)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| README | met | 30 / 30 | — |
| Documentation directory | met | 25 / 25 | — |
| Documentation / homepage site | met | 15 / 15 | https://endojs.org/ |
| Repository description | met | 10 / 10 | — |
| Topics | met | 10 / 10 | 11 topics |
| Wiki | met | 10 / 10 | — |

## Security — 82/100 (Excellent)

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 — 78/100 (Good)

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

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Binary-Artifacts | partial | 6.8 / 7.5 | binaries present in source code |
| Branch-Protection | partial | 3.8 / 7.5 | branch protection is not maximal on development and all release branches |
| CI-Tests | met | 2.5 / 2.5 | 22 out of 22 merged PRs checked by a CI test -- score normalized to 10 |
| CII-Best-Practices | not met | 0 / 2.5 | no effort to earn an OpenSSF best practices badge detected |
| Code-Review | met | 7.5 / 7.5 | all changesets reviewed |
| Contributors | met | 2.5 / 2.5 | project has 55 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 | 30 commit(s) and 12 issue activity found in the last 90 days -- score normalized to 10 |
| Packaging | excluded | 0 / 5 | packaging workflow not detected |
| Pinned-Dependencies | partial | 4.5 / 5 | dependency not pinned by hash detected -- score normalized to 9 |
| SAST | not met | 0 / 5 | SAST tool is not run on all commits -- score normalized to 0 |
| Security-Policy | met | 5 / 5 | security policy file detected |
| Signed-Releases | excluded | 0 / 7.5 | no releases found |
| Token-Permissions | met | 7.5 / 7.5 | GitHub workflow tokens follow principle of least privilege |
| Vulnerabilities | not met | 0 / 7.5 | 65 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 npm:@endo/exo@1.7.0 runtime dependency closure — what installing the published package pulls in — 14 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 — 89/100 (Excellent)

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 — 85/100 (Excellent)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Agent instructions | met | 45 / 45 | AGENTS.md, CLAUDE.md |
| Machine-readable docs (llms.txt) | not met | 0 / 15 | — |
| Legible commit history | met | 40 / 40 | 89 of 90 human commits state their intent (structured subject or explanatory body) |

### Verify loop (build / test / typecheck) — 90/100 (Excellent)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| One-command bootstrap | partial | 12.6 / 18 | Cargo.toml, rust/ocapn_noise/Cargo.toml (toolchain convention, no task runner) |
| Automated tests | met | 22 / 22 | — |
| Lint / format config | met | 11 / 11 | .eslintrc.json, eslint.config.js, package.json ("prettier"), packages/compartment-mapper/package.json ("prettier") |
| Static type checking | met | 11 / 11 | browser-test/tsconfig.json, packages/base64/tsconfig.json, packages/benchmark/tsconfig.json, packages/bundle-source/tsconfig.json, packages/bytes/tsconfig.json, packages/cache-map/tsconfig.json, packages/captp/tsconfig.json, packages/chacha12-fast-check-test/tsconfig.json, packages/chacha12/tsconfig.json, packages/check-bundle/tsconfig.json, packages/cjs-module-analyzer/tsconfig.json, packages/cli/tsconfig.json, packages/common/tsconfig.json, packages/compartment-mapper/tsconfig.json, packages/daemon/tsconfig.json, packages/env-options/tsconfig.json, packages/errors/tsconfig.json, packages/eslint-plugin/tsconfig.json, packages/evasive-transform/tsconfig.json, packages/eventual-send/tsconfig.json, packages/exo/tsconfig.json, packages/far/tsconfig.json, packages/goblin-chat/tsconfig.json, packages/harden/tsconfig.json, packages/hex/tsconfig.json, packages/immutable-arraybuffer/tsconfig.json, packages/import-bundle/tsconfig.json, packages/init/tsconfig.json, packages/lp32/tsconfig.json, packages/marshal/tsconfig.json, packages/memoize/tsconfig.json, packages/module-source/tsconfig.json, packages/nat/tsconfig.json, packages/netstring/tsconfig.json, packages/ocapn-noise/tsconfig.json, packages/ocapn/tsconfig.json, packages/panic/tsconfig.json, packages/parser-pipeline/tsconfig.json, packages/pass-style/tsconfig.json, packages/path-compare/tsconfig.json, packages/patterns/tsconfig.json, packages/promise-kit/tsconfig.json, packages/random/tsconfig.json, packages/ses-ava/tsconfig.json, packages/ses/tsconfig.json, packages/skel/tsconfig.json, packages/stream-node/tsconfig.json, packages/stream-types-test/tsconfig.json, packages/stream/tsconfig.json, packages/syrup-frame/tsconfig.json, packages/test262-runner/tsconfig.json, packages/trampoline/tsconfig.json, packages/where/tsconfig.json, packages/zip/tsconfig.json, scripts/endo-changelog/tsconfig.json, scripts/tsconfig.json, tsconfig.json |
| Reproducible environment | met | 10 / 10 | lockfile |
| Demonstrated agent practice | partial | 6 / 10 | 3 of the last 100 commits agent-authored or agent-credited |
| Automated maintenance | met | 8 / 8 | 8 of the last 100 commits are automated dependency updates |
| OpenSSF Scorecard: Pinned-Dependencies | partial | 9 / 10 | dependency not pinned by hash detected -- score normalized to 9 |

### Code legibility for models — 82/100 (Excellent)

| Criterion | Status | Points | Detail |
|---|---|---|---|
| Type-checkable code | partial | 27 / 45 | JavaScript with type-check config (browser-test/tsconfig.json, packages/base64/tsconfig.json, packages/benchmark/tsconfig.json, packages/bundle-source/tsconfig.json, packages/bytes/tsconfig.json, packages/cache-map/tsconfig.json, packages/captp/tsconfig.json, packages/chacha12-fast-check-test/tsconfig.json, packages/chacha12/tsconfig.json, packages/check-bundle/tsconfig.json, packages/cjs-module-analyzer/tsconfig.json, packages/cli/tsconfig.json, packages/common/tsconfig.json, packages/compartment-mapper/tsconfig.json, packages/daemon/tsconfig.json, packages/env-options/tsconfig.json, packages/errors/tsconfig.json, packages/eslint-plugin/tsconfig.json, packages/evasive-transform/tsconfig.json, packages/eventual-send/tsconfig.json, packages/exo/tsconfig.json, packages/far/tsconfig.json, packages/goblin-chat/tsconfig.json, packages/harden/tsconfig.json, packages/hex/tsconfig.json, packages/immutable-arraybuffer/tsconfig.json, packages/import-bundle/tsconfig.json, packages/init/tsconfig.json, packages/lp32/tsconfig.json, packages/marshal/tsconfig.json, packages/memoize/tsconfig.json, packages/module-source/tsconfig.json, packages/nat/tsconfig.json, packages/netstring/tsconfig.json, packages/ocapn-noise/tsconfig.json, packages/ocapn/tsconfig.json, packages/panic/tsconfig.json, packages/parser-pipeline/tsconfig.json, packages/pass-style/tsconfig.json, packages/path-compare/tsconfig.json, packages/patterns/tsconfig.json, packages/promise-kit/tsconfig.json, packages/random/tsconfig.json, packages/ses-ava/tsconfig.json, packages/ses/tsconfig.json, packages/skel/tsconfig.json, packages/stream-node/tsconfig.json, packages/stream-types-test/tsconfig.json, packages/stream/tsconfig.json, packages/syrup-frame/tsconfig.json, packages/test262-runner/tsconfig.json, packages/trampoline/tsconfig.json, packages/where/tsconfig.json, packages/zip/tsconfig.json, scripts/endo-changelog/tsconfig.json, scripts/tsconfig.json, tsconfig.json) |
| Manageable file sizes | partial | 55 / 55 | 5/39106 source files over 60KB |

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

Excluded from scoring (no data or not applicable): API schema (OpenAPI/GraphQL/proto), MCP server. Remaining weights renormalized.

| Criterion | Status | Points | Detail |
|---|---|---|---|
| API schema (OpenAPI/GraphQL/proto) | excluded | 0 / 40 | not applicable to this kind of software |
| MCP server | excluded | 0 / 20 | not applicable to this kind of software |
| Runnable examples | met | 40 / 40 | demos |

## 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