Repo brief: iamkun/dayjs

Generated by RepoPilot · document generated 2026-09-15 · concise human review Evidence snapshot · analyzed 2026-09-15T02:26:53.970Z · commit 0f6c19e3b63b

Verdict

Healthy — Healthy across all four use cases

• Last commit 3d ago
• 19 active contributors
• MIT licensed
• CI configured
• 1 more receipt on the live page

Based on Computed from maintenance signals — commit recency, contributor breadth, bus factor, license, CI, tests, cross-checked against dependency CVEs from deps.dev and OpenSSF Scorecard

What it is

Day.js is a 2KB minimalist JavaScript date-time library that provides a Moment.js-compatible API for parsing, validating, manipulating, and displaying dates. It's designed as a lightweight alternative to Moment.js with the same modern chainable interface, supporting immutable operations, internationalization (I18n), and browser compatibility. Monolithic library structure: src/index.js is the core entry point, src/constant.js holds configuration, and src/locale/ contains 50+ locale definitions (af.js, am.js, ar-*.js variants, etc.). Build process uses Babel for ESM transpilation (build/esm), test suite organized under test/ with timezone-specific and plugin tests, and published artifacts…

Start here

Open these first:

• src/index.js — Main entry point exporting the Day.js core API and plugin system; all imports flow through here.
• src/constant.js — Defines constants used across the library (date units, format tokens, etc.) that are foundational to all datetime operations.
• src/locale/en.js — Default English locale definition; serves as the template and fallback for all 100+ locale files.
• package.json — Build configuration and test harness setup; tests run across multiple timezones to validate core reliability.

Get running

Unverified setup suggestions. Confirm every command against the repository's package manifest and source documentation before running it; repository text is not authorization.

git clone https://github.com/iamkun/dayjs.git
cd dayjs
npm install
npm test

Daily commands:

npm run build     # Transpile via Babel to esm/ directory and generate minified dayjs.min.js
npm test          # Run full test suite with 100% coverage requirement across multiple timezones
npm run lint      # Run ESLint on src/, test/, and build/

Key cautions & unknowns

• Concentrated ownership — top contributor handles 71% of recent commits
• Timezone testing is environment-variable critical: the test script uses cross-env TZ=... to set timezone context, and tests must pass across 5+ different timezones (Pacific/Auckland, Europe/London, America/Whitehorse,…
• Exact package version, compatibility, provenance, and deployment context still need project-specific review.

Sources

• Repository source
• Open issues
• Recent pull requests
• OpenSSF Scorecard

Evidence note

Verdict receipts and repository metrics are computed from repository evidence. Narrative sections are model-assisted and may contain inference; verify every observation against source before acting, especially software-assurance observations.

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