# caolan/async

Async utilities for node and the browser

Repository: https://github.com/caolan/async
Canonical: https://ross.abutalabs.com/products/async
Homepage: http://caolan.github.io/async/
Language: JavaScript
License: MIT
License Family: permissive
Topics: javascript, async, callbacks
Last push: 2026-08-07T17:03:35+00:00

## Health v2 (maintenance only)
Score: 66/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 96, release rhythm 8, longevity 100
- inputs: {"age_days": 5937, "days_push": 26, "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 28136, forks 2377 (observed 2026-08-28T04:11:48.130146+00:00)

## What it is
Async is a JavaScript utility module providing higher-order functions and common patterns for working with asynchronous code, such as series, parallel, waterfall, and queue control flow. It works in Node.js and the browser, with both CommonJS and ESM builds available.

## Use cases
- run async tasks in parallel with a concurrency limit
- execute functions in series or waterfall order
- manage async queues and worker pools
- map/filter/reduce over collections with async callbacks
- avoid callback hell in Node.js code

## When to choose
- you maintain callback-style Node.js code and need robust async control flow
- you need battle-tested utilities like queue, cargo, and retry
- you want a dependency-free utility that also works in the browser

## When to avoid
- you write modern code using native Promises and async/await with built-in Promise combinators
- you prefer newer alternatives like p-limit or bluebird for promise-based flows

## Facets
- artifact type: library
- maturity: stable
- function: concurrency, developer-tools
- domain: developer-tools, web-development, cross-platform
- platform: browser
- tags: async-utilities, callbacks, control-flow, higher-order-functions, esm, nodejs, javascript

## Member repositories
- caolan/async (main) score 66

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:48.130146+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 2026-08-29T16:54:26.949074+00:00, confidence not recorded.
  - readme: https://github.com/caolan/async (fetched 2026-08-28T04:11:48.130146+00:00, sha 7fce5b80bafa)
  - homepage: http://caolan.github.io/async/ (fetched 2026-08-29T07:51:22.270473+00:00, sha 44136fa355b3)
  - registry_npm: https://registry.npmjs.org/async (fetched 2026-08-29T07:51:22.279442+00:00, sha 354193ad0204)
- Data as of 2026-08-30T08:39:29.467469+00:00.