# tc39/ecma262

Status, process, and documents for ECMA-262

Repository: https://github.com/tc39/ecma262
Canonical: https://ross.abutalabs.com/products/ecma262
Homepage: https://tc39.es/ecma262/
Language: HTML
License: NOASSERTION
License Family: other
Topics: ecmascript, javascript
Last push: 2026-08-26T16:41:21+00:00

## Health v2 (maintenance only)
Score: 87/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 63, longevity 100
- inputs: {"age_days": 4529, "days_push": 7, "days_rel": 37, "gap_med": 196.5, "n_releases_24m": 3}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 15679, forks 1429 (observed 2026-08-28T04:11:13.727292+00:00)

## What it is
The official source repository for ECMA-262, the ECMAScript (JavaScript) Language Specification, maintained by TC39. It contains the draft specification text, build tooling to render it as a readable document, and links to the TC39 proposal process.

## Use cases
- read the official ECMAScript language specification
- check how a JavaScript language feature is defined normatively
- track the status of TC39 proposals for new JS features
- contribute a new proposal to the ECMAScript standard
- build the spec draft locally to review upcoming changes
- look up precise semantics of syntax like grammars and built-in objects

## When to choose
- you need the authoritative, normative definition of JavaScript/ECMAScript behavior
- you are implementing a JS engine or transpiler and need exact semantics
- you want to follow or participate in the TC39 standardization process

## When to avoid
- you want a beginner-friendly JavaScript tutorial or learning guide
- you need runnable code, libraries, or tools rather than a specification document
- you need documentation for a specific JS runtime's APIs like Node.js or the DOM

## Facets
- artifact type: learning-resource
- maturity: active
- function: documentation, programming-language
- domain: programming-languages, documentation, web-development
- platform: cli
- tags: ecmascript, javascript, language-specification, tc39, standards, spec-draft, web-server

## Member repositories
- tc39/ecma262 (main) score 87

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:13.727292+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:05:35.049763+00:00, confidence not recorded.
  - readme: https://github.com/tc39/ecma262 (fetched 2026-08-28T04:11:13.727292+00:00, sha 68872cf8dcff)
  - homepage: https://tc39.es/ecma262/ (fetched 2026-08-29T08:03:30.444494+00:00, sha 1eb9f1040f59)
- Data as of 2026-08-30T08:39:29.467469+00:00.