# bittorrent/libutp

uTorrent Transport Protocol library

Repository: https://github.com/bittorrent/libutp
Canonical: https://ross.abutalabs.com/products/libutp
Homepage: http://github.com/bittorrent/libutp
Language: C++
License: MIT
License Family: permissive
Last push: 2023-10-19T22:11:58+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": 5949, "days_push": 1049, "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 1159, forks 266 (observed 2026-08-28T04:03:48.649172+00:00)

## What it is
libutp is a C++ library implementing the uTorrent Transport Protocol (uTP), a TCP-like reliable transport over UDP based on LEDBAT congestion control (BEP-29). It exposes a callback-driven ANSI C89 API for event-based, low-extra-delay data transfer.

## Use cases
- implement BitTorrent peer connections with uTP transport
- add LEDBAT-based low-delay reliable transfer over UDP to an application
- build event-driven networking without blocking socket calls
- transfer data between peers without saturating the user's link
- embed a reliable UDP protocol in a C or C++ application

## When to choose
- you need reliable ordered delivery over UDP with minimal added delay
- you are building a BitTorrent client or P2P application
- you want a small embeddable C-API transport library
- you need LEDBAT congestion control to yield to other traffic

## When to avoid
- you need a thread-safe socket API out of the box
- you require a stable, versioned API across upgrades
- you need general-purpose TCP replacement with TLS and rich features
- you want an actively developed project with frequent releases

## Facets
- artifact type: library
- maturity: maintenance
- function: networking, concurrency, developer-tools
- domain: networking, microservices
- platform: cpp, c, windows, cross-platform
- tags: udp, ledbat, congestion-control, transport-protocol, bittorrent, bep-29, p2p, reliable-udp, linux, macos

## Member repositories
- bittorrent/libutp (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:48.649172+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 2026-08-30T06:31:52.626940+00:00, confidence not recorded.
  - readme: https://github.com/bittorrent/libutp (fetched 2026-08-28T04:03:48.649172+00:00, sha e8844ee925b4)
  - homepage: http://github.com/bittorrent/libutp (fetched 2026-08-29T12:36:25.780046+00:00, sha f45441d000bb)
- Data as of 2026-08-30T08:39:29.467469+00:00.