# libevent/libevent

Event notification library

Repository: https://github.com/libevent/libevent
Canonical: https://ross.abutalabs.com/products/libevent
Homepage: https://libevent.org
Language: C
License: NOASSERTION
License Family: other
Topics: c, cross-platform, async, networking
Last push: 2026-08-26T06:17:56+00:00

## Health v2 (maintenance only)
Score: 96/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 91, longevity 100
- inputs: {"age_days": 5567, "days_push": 7, "days_rel": 63, "gap_med": 0, "n_releases_24m": 2}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 11942, forks 3464 (observed 2026-08-28T04:10:50.537135+00:00)

## What it is
libevent is a C library providing a portable event notification API that executes callbacks on file descriptor events, timeouts, and signals. It replaces hand-written event loops in event-driven network servers and includes buffered I/O, DNS, HTTP, and a minimal RPC framework.

## Use cases
- write a high-performance event-driven network server in C
- replace select/poll event loops with a portable abstraction
- build an async HTTP server or client
- handle timers and signals in a single event loop
- write multi-threaded networked applications with scalable I/O
- implement DNS or minimal RPC protocols

## When to choose
- you need a mature, portable C event loop across Linux, BSD, macOS, and Windows
- you want epoll/kqueue/select abstraction without rewriting your event loop
- you need buffered network I/O with SSL, rate-limiting, or zero-copy file transmission
- you are building a dependency for other software (e.g., Tor, memcached-style servers)

## When to avoid
- you are in a language with built-in async runtimes (Node.js, Go, Rust tokio)
- you need a full-featured HTTP framework rather than a low-level event library
- you want a modern coroutine/async-await programming model
- your project is not in C/C++ and binding overhead matters

## Facets
- artifact type: library
- maturity: stable
- function: networking, concurrency, http-server, rpc, caching
- domain: networking, developer-tools, backend, cross-platform
- platform: windows, bsd, cross-platform, c
- tags: event-loop, async-io, epoll, kqueue, bufferevents, dns, c10k, linux, macos

## Member repositories
- libevent/libevent (main) score 96

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:10:50.537135+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 2026-08-29T17:15:03.310577+00:00, confidence not recorded.
  - readme: https://github.com/libevent/libevent (fetched 2026-08-28T04:10:50.537135+00:00, sha 915d0c999264)
  - homepage: https://libevent.org (fetched 2026-08-29T08:12:52.818835+00:00, sha 7b5665a9f72b)
  - site_page: https://libevent.org/old-releases.html (fetched 2026-08-29T08:12:52.828739+00:00, sha fe8ad9bacf6e)
- Data as of 2026-08-30T08:39:29.467469+00:00.