# hyperium/h2

HTTP 2.0 client & server implementation for Rust.

Repository: https://github.com/hyperium/h2
Canonical: https://ross.abutalabs.com/products/h2
Language: Rust
License: MIT
License Family: permissive
Topics: rust, tokio, http2
Last push: 2026-08-25T17:58:04+00:00

## Health v2 (maintenance only)
Score: 95/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 87, longevity 100
- inputs: {"age_days": 3463, "days_push": 8, "days_rel": 9, "gap_med": 48.5, "n_releases_24m": 13}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1544, forks 374 (observed 2026-08-28T04:05:01.300863+00:00)

## What it is
H2 is a Tokio-based HTTP/2 client and server implementation for Rust that implements the full HTTP/2 specification. It serves as the low-level protocol layer used by the hyper HTTP library, leaving connection management, TLS, and HTTP/1 upgrades to higher-level crates.

## Use cases
- implement http/2 protocol in rust
- build an http/2 server on tokio
- make http/2 client requests in rust
- low-level http/2 framing and streams
- embed http/2 support in a custom http library
- conformance-test compliant http/2 implementation

## When to choose
- you need direct, spec-complete control over HTTP/2 in a Tokio application
- you are building an HTTP library or framework on top of HTTP/2
- you need a well-tested implementation that passes h2spec

## When to avoid
- you want a full-featured HTTP client/server with TLS and connection pooling - use hyper instead
- you need HTTP/1.x support or upgrade handling
- you are not using the Tokio async runtime

## Facets
- artifact type: library
- maturity: stable
- function: http-server, http-client, concurrency
- domain: web-development, backend, networking, developer-tools
- platform: rust, cross-platform
- tags: http2, tokio, async, protocol-implementation

## Member repositories
- hyperium/h2 (main) score 95

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:05:01.300863+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 2026-08-30T04:30:38.235840+00:00, confidence not recorded.
  - readme: https://github.com/hyperium/h2 (fetched 2026-08-28T04:05:01.300863+00:00, sha 5981f9df0b61)
  - registry_crates: https://crates.io/api/v1/crates/h2 (fetched 2026-08-29T11:31:48.185600+00:00, sha 649e8454e1a2)
- Data as of 2026-08-30T08:39:29.467469+00:00.