# parallel-js/parallel.js

Easy multi-core processing utilities for Node.

Repository: https://github.com/parallel-js/parallel.js
Canonical: https://ross.abutalabs.com/products/paralleljs
Language: JavaScript
License: MIT
License Family: permissive
Topics: parallel, javascript, worker-threads, paralleljs, node, webworker
Last push: 2026-08-26T17:37:16+00:00

## Health v2 (maintenance only)
Score: 67/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 99, release rhythm 8, longevity 100
- inputs: {"age_days": 4952, "days_push": 7, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 3246, forks 197 (observed 2026-08-28T04:07:50.659786+00:00)

## What it is
Parallel.js is a JavaScript library that simplifies parallel computing by running functions on worker threads in the browser (via Web Workers) and child processes in Node.js. It provides a chainable API for spawning parallel jobs over serializable data.

## Use cases
- run cpu-heavy javascript off the main thread
- parallelize map operations over an array in node
- use web workers without writing worker boilerplate
- distribute computation across multiple cores
- process large datasets concurrently in the browser

## When to choose
- you need simple multi-core processing in Node or the browser with a minimal chained API
- your data is JSON-serializable and tasks are independent function calls

## When to avoid
- you need fine-grained control over worker pools, shared memory, or transferable objects
- your functions rely on closures or non-serializable state, since data must be JSON-serializable
- you need a modern, actively developed concurrency solution

## Facets
- artifact type: library
- maturity: maintenance
- function: concurrency, serialization
- domain: developer-tools, web-development, backend
- platform: browser, cross-platform
- tags: parallel-computing, web-workers, child-processes, multi-core, chained-api, nodejs, javascript

## Member repositories
- parallel-js/parallel.js (main) score 67

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:07:50.659786+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 2026-08-30T07:24:28.541502+00:00, confidence not recorded.
  - readme: https://github.com/parallel-js/parallel.js (fetched 2026-08-28T04:07:50.659786+00:00, sha 7ef18cb09c6c)
- Data as of 2026-08-30T08:39:29.467469+00:00.