# mozilla/gecko-dev

SUPERSEDED by https://github.com/mozilla-firefox/firefox.  Read-only Git mirror of the Mercurial gecko repositories at https://hg.mozilla.org

Repository: https://github.com/mozilla/gecko-dev
Canonical: https://ross.abutalabs.com/products/gecko-dev
Homepage: https://firefox-source-docs.mozilla.org/setup/index.html
Language: JavaScript
License: NOASSERTION
License Family: other
Archived: true
Last push: 2025-07-09T03:21:12+00:00

## Health v2 (maintenance only)
Score: 10/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 30, release rhythm 35, longevity 100
- inputs: {"age_days": 4709, "days_push": 420, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, archived, no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 3702, forks 2135 (observed 2026-08-28T04:08:14.991742+00:00)

## What it is
A read-only Git mirror of Mozilla's Mercurial repositories containing the Gecko engine and Firefox browser source code. This repository has been superseded by the mozilla-firefox/firefox GitHub repository, though it remains a historical mirror of the Firefox codebase.

## Use cases
- browse Firefox source code on GitHub
- search Gecko engine source in Git format
- contribute patches to Firefox
- build Firefox from source
- study browser engine internals
- set up a Firefox development environment

## When to choose
- you need Git-based access to Firefox/Gecko source history
- you want to build or hack on the Firefox browser codebase
- you are studying how a production web browser engine is implemented

## When to avoid
- you want the actively maintained repository - use mozilla-firefox/firefox instead
- you just want to use the Firefox browser as an end user
- you need a lightweight embeddable engine rather than a full browser codebase

## Facets
- artifact type: application
- maturity: maintenance
- function: developer-tools, documentation, testing, browser-extension
- domain: web-development, developer-tools, cross-platform
- platform: cross-platform, windows, cpp, rust
- tags: firefox, gecko, web-browser, git-mirror, mozilla, browser-engine, source-code, browsers, linux, macos, android, ios, javascript

## Member repositories
- mozilla/gecko-dev (main) score 10

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:08:14.991742+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 2026-08-29T18:31:01.368641+00:00, confidence not recorded.
  - readme: https://github.com/mozilla/gecko-dev (fetched 2026-08-28T04:08:14.991742+00:00, sha 4ae68b931b05)
  - homepage: https://firefox-source-docs.mozilla.org/setup/index.html (fetched 2026-08-29T09:24:54.410255+00:00, sha 72ec10347ae8)
  - site_page: https://firefox-source-docs.mozilla.org/index.html (fetched 2026-08-29T09:24:54.419319+00:00, sha 23d5dbede3b0)
  - site_page: https://firefox-source-docs.mozilla.org/devtools-user/about_colon_debugging/index.html (fetched 2026-08-29T09:24:54.421585+00:00, sha ff333d907452)
  - site_page: https://firefox-source-docs.mozilla.org/devtools-user/index.html (fetched 2026-08-29T09:24:54.423827+00:00, sha bb0398eb9a93)
  - site_page: https://firefox-source-docs.mozilla.org/devtools/index.html (fetched 2026-08-29T09:24:54.426762+00:00, sha 1e26958c1196)
  - site_page: https://firefox-source-docs.mozilla.org/tools/moztreedocs/index.html (fetched 2026-08-29T09:24:54.428986+00:00, sha dcbba387028c)
  - site_page: https://firefox-source-docs.mozilla.org/testing/perfdocs/index.html (fetched 2026-08-29T09:24:54.430969+00:00, sha bf18ab538a80)
- Data as of 2026-08-30T08:39:29.467469+00:00.