# StephenCleary/AsyncEx

A helper library for async/await.

Repository: https://github.com/StephenCleary/AsyncEx
Canonical: https://ross.abutalabs.com/products/asyncex
Language: C#
License: MIT
License Family: permissive
Topics: c-sharp, async, await, asyncex, async-await, task
Last push: 2024-01-01T05:30:30+00:00

## Health v2 (maintenance only)
Score: 32/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 4501, "days_push": 975, "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 3724, forks 373 (observed 2026-08-28T04:08:15.615193+00:00)

## What it is
A C# helper library providing async-compatible coordination primitives for async/await code, such as AsyncLock, AsyncSemaphore, and AsyncManualResetEvent. It targets netstandard1.3/2.0 and is distributed via the Nito.AsyncEx NuGet package.

## Use cases
- lock asynchronously in C# without blocking threads
- use a semaphore or manual reset event with await
- synchronize async code with cancellation support
- replace lock statements in async methods
- coordinate async tasks with reader-writer locks

## When to choose
- you write async/await C# code and need async-compatible locking or signaling primitives
- you need cancellation-aware synchronization in .NET
- you target .NET Core, .NET Framework 4.6+, Xamarin, or UWP

## When to avoid
- your code is purely synchronous and standard lock/Monitor suffices
- you need primitives not covered by the library and prefer building custom solutions
- you are on a platform below netstandard1.3

## Facets
- artifact type: library
- maturity: maintenance
- function: concurrency, developer-tools
- domain: developer-tools
- platform: dotnet, cross-platform
- tags: async-await, csharp, async-lock, coordination-primitives, task, algorithms

## Member repositories
- StephenCleary/AsyncEx (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:08:15.615193+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 2026-08-29T18:29:16.869108+00:00, confidence not recorded.
  - readme: https://github.com/StephenCleary/AsyncEx (fetched 2026-08-28T04:08:15.615193+00:00, sha c37974ac043d)
- Data as of 2026-08-30T08:39:29.467469+00:00.