# rust-lang/async-book

Asynchronous Programming in Rust

Repository: https://github.com/rust-lang/async-book
Canonical: https://ross.abutalabs.com/products/async-book
Homepage: https://rust-lang.github.io/async-book/index.html
Language: Shell
License: MIT
License Family: permissive
Topics: async-foundations
Last push: 2026-05-24T20:45:45+00:00

## Health v2 (maintenance only)
Score: 70/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 84, release rhythm 35, longevity 100
- inputs: {"age_days": 2821, "days_push": 101, "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 2198, forks 284 (observed 2026-08-28T04:06:25.359853+00:00)

## What it is
The official Rust async book, a guide to asynchronous programming in Rust from beginner to advanced topics, built with mdbook. It is currently undergoing a rewrite after a long unmaintained period.

## Use cases
- learn async programming in Rust from scratch
- understand Rust futures and executors
- find advanced async Rust topics like pinning and streams
- reference guide for async/await in Rust
- onboard a team to async Rust development

## When to choose
- you already know Rust and want to learn async/await
- you want an official, free, in-depth written guide
- you need both beginner and advanced async Rust material

## When to avoid
- you need up-to-date, polished content right now (it is mid-rewrite with gaps and duplication)
- you want a hands-on tutorial or course rather than a book
- you are learning Rust itself rather than async Rust

## Facets
- artifact type: learning-resource
- maturity: maintenance
- function: documentation
- domain: developer-tools, tutorials, programming-languages
- platform: cross-platform
- tags: rust, async, book, mdbook, concurrency, education

## Member repositories
- rust-lang/async-book (main) score 70

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:06:25.359853+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 2026-08-30T02:47:09.286622+00:00, confidence not recorded.
  - readme: https://github.com/rust-lang/async-book (fetched 2026-08-28T04:06:25.359853+00:00, sha 68e0cbd47a9c)
  - homepage: https://rust-lang.github.io/async-book/index.html (fetched 2026-08-29T10:27:19.094893+00:00, sha 321e9a298ebc)
- Data as of 2026-08-30T08:39:29.467469+00:00.