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Ecma TC39

Ecma International, Technical Committee 39 - ECMAScript

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TC39

Ecma International's TC39 is a group of JavaScript developers, implementers, academics, and more, collaborating with the community to maintain and evolve the definition of JavaScript.

Contribute

TC39 welcomes contributions from the JavaScript community, whether it is feedback on existing proposals, improved documentation, testing, implementations, or even language feature ideas. See our contributor guide for details.

Important

To participate in TC39 meetings as a member, join Ecma.

Specifications

We develop the JavaScript (formally, ECMAScript) specification, the Internationalization API specification, the Source Map specification, and, of course, JSON! We meet every two months to discuss proposals. To learn more about the process, please take a look at the six stages for new language feature proposals. See our meeting agendas and minutes to learn more.

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  1. ecma262 ecma262 Public

    Status, process, and documents for ECMA-262

    HTML 15.6k 1.4k

  2. ecma402 ecma402 Public

    Status, process, and documents for ECMA 402

    HTML 597 115

  3. test262 test262 Public

    Official ECMAScript Conformance Test Suite

    JavaScript 2.7k 533

  4. proposals proposals Public

    Tracking ECMAScript Proposals

    19.1k 746

  5. agendas agendas Public

    TC39 meeting agendas

    JavaScript 1.2k 201

  6. notes notes Public

    TC39 meeting notes

    JavaScript 706 125

Repositories

Showing 10 of 324 repositories
  • dataset Public

    The automatic track tc39 proposals

    tc39/dataset’s past year of commit activity
    TypeScript 47 Unlicense 11 2 0 Updated Mar 25, 2026
  • agendas Public

    TC39 meeting agendas

    tc39/agendas’s past year of commit activity
    JavaScript 1,171 201 0 3 Updated Mar 24, 2026
  • proposal-source-phase-imports Public

    Proposal to enable importing modules at the source phase

    tc39/proposal-source-phase-imports’s past year of commit activity
    HTML 158 MIT 11 7 3 Updated Mar 25, 2026
  • proposal-temporal Public

    Provides standard objects and functions for working with dates and times.

    tc39/proposal-temporal’s past year of commit activity
    HTML 3,679 174 16 5 Updated Mar 24, 2026
  • tc39/proposal-esm-phase-imports’s past year of commit activity
    HTML 53 MIT 2 4 4 Updated Mar 24, 2026
  • ecma262 Public

    Status, process, and documents for ECMA-262

    tc39/ecma262’s past year of commit activity
    HTML 15,609 1,406 356 (9 issues need help) 120 Updated Mar 24, 2026
  • ecma402 Public

    Status, process, and documents for ECMA 402

    tc39/ecma402’s past year of commit activity
    HTML 597 115 162 7 Updated Mar 24, 2026
  • proposals Public

    Tracking ECMAScript Proposals

    tc39/proposals’s past year of commit activity
    19,091 746 3 4 Updated Mar 23, 2026
  • proposal-amount Public

    Numbers with precision and a unit for JavaScript

    tc39/proposal-amount’s past year of commit activity
    HTML 47 MIT 8 36 5 Updated Mar 23, 2026
  • notes Public

    TC39 meeting notes

    tc39/notes’s past year of commit activity
    JavaScript 706 125 1 (1 issue needs help) 7 Updated Mar 23, 2026