# cognitect-labs/transducers-js

Transducers for JavaScript

Repository: https://github.com/cognitect-labs/transducers-js
Canonical: https://ross.abutalabs.com/products/transducers-js
Language: JavaScript
License: Apache-2.0
License Family: permissive
Archived: true
Last push: 2023-06-03T21:41:12+00:00

## Health v2 (maintenance only)
Score: 10/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 4362, "days_push": 1187, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, archived
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1602, forks 43 (observed 2026-08-28T04:05:09.734189+00:00)

## What it is
A high-performance JavaScript implementation of transducers, composable algorithmic transformations decoupled from input and output sources. It lets you build map/filter/reduce pipelines that work over collections, streams, channels, and observables without intermediate aggregates.

## Use cases
- compose map and filter transformations without intermediate arrays
- apply the same transformation pipeline to collections, streams, and observables
- efficiently transform large sequences in JavaScript
- build reusable data transformation pipelines
- reduce over iterables with composable transformers

## When to choose
- you need composable, context-independent transformations in JavaScript
- you want transducer semantics matching Clojure's model
- you need a tiny (2K gzipped) dependency for data transformation

## When to avoid
- you need an actively maintained library - it is explicitly unmaintained
- you only need simple array operations covered by native ES6 methods
- you want modern ESM/TypeScript support

## Facets
- artifact type: library
- maturity: abandoned
- function: serialization
- domain: developer-tools
- platform: browser, cross-platform
- tags: transducers, functional-programming, data-transformation, unmaintained, algorithms, nodejs

## Member repositories
- cognitect-labs/transducers-js (main) score 10

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:05:09.734189+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 2026-08-30T03:52:37.220452+00:00, confidence not recorded.
  - readme: https://github.com/cognitect-labs/transducers-js (fetched 2026-08-28T04:05:09.734189+00:00, sha ed6af6820ea8)
- Data as of 2026-08-30T08:39:29.467469+00:00.