# facebook/fbjs

A collection of utility libraries used by other Meta JS projects.

Repository: https://github.com/facebook/fbjs
Canonical: https://ross.abutalabs.com/products/fbjs
Language: JavaScript
License: MIT
License Family: permissive
Last push: 2026-01-21T23:17:02+00:00

## Health v2 (maintenance only)
Score: 61/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 63, release rhythm 35, longevity 100
- inputs: {"age_days": 4115, "days_push": 224, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1961, forks 309 (observed 2026-08-28T04:05:59.483254+00:00)

## What it is
FBJS is a collection of utility libraries published by Meta to share JavaScript code across its own projects like React and Relay. It is primarily intended for internal Meta use, with APIs that may change without strict semver guarantees.

## Use cases
- share common JavaScript utilities across multiple projects
- use the same helper libraries that React and Relay depend on
- consume small utility packages from a monorepo
- find lightweight JS helpers for events, DOM, or core utilities

## When to choose
- you are working within Meta's JS ecosystem or need compatibility with its projects
- you need a specific small utility package that FBJS provides

## When to avoid
- you want a stable, semver-guaranteed library for production use
- you expect feature requests or community support
- a more general-purpose utility library like lodash would fit better

## Facets
- artifact type: library
- maturity: maintenance
- function: developer-tools
- domain: developer-tools, web-development, frontend
- platform: browser
- tags: utilities, facebook, meta, monorepo, shared-code, nodejs, javascript

## Member repositories
- facebook/fbjs (main) score 61

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:05:59.483254+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 2026-08-30T03:05:37.921238+00:00, confidence not recorded.
  - readme: https://github.com/facebook/fbjs (fetched 2026-08-28T04:05:59.483254+00:00, sha f3452cdd1af5)
  - registry_npm: https://registry.npmjs.org/fbjs (fetched 2026-08-29T10:45:54.636655+00:00, sha 4a3b53f94bd1)
- Data as of 2026-08-30T08:39:29.467469+00:00.