# rust-lang/futures-rs

Zero-cost asynchronous programming in Rust

Repository: https://github.com/rust-lang/futures-rs
Canonical: https://ross.abutalabs.com/products/futures-rs
Homepage: https://rust-lang.github.io/futures-rs/
Language: Rust
License: Apache-2.0
License Family: permissive
Topics: async-foundations
Last push: 2026-08-11T12:35:06+00:00

## Health v2 (maintenance only)
Score: 89/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 97, release rhythm 73, longevity 100
- inputs: {"age_days": 3808, "days_push": 22, "days_rel": 22, "gap_med": 153, "n_releases_24m": 4}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 5909, forks 705 (observed 2026-08-28T04:09:32.160687+00:00)

## What it is
futures-rs is the foundational Rust library for asynchronous programming, providing core trait definitions like Stream plus utilities such as join!, select!, and futures combinators. It supports zero-cost async abstractions and works in no_std environments including bare metal.

## Use cases
- write async code in rust
- combine multiple futures with join and select
- work with async streams in rust
- use async in embedded no_std projects
- build async control flow utilities

## When to choose
- you need core async traits and combinators in Rust
- you want no_std async support
- you're building async runtimes or libraries on stable foundations

## When to avoid
- you only need an async runtime like tokio for executing tasks
- you want batteries-included async I/O rather than foundational traits

## Facets
- artifact type: library
- maturity: stable
- function: concurrency, developer-tools
- domain: programming-languages, developer-tools
- platform: rust, cross-platform, embedded
- tags: async, futures, streams, no-std, combinators, zero-cost-abstraction, algorithms

## Member repositories
- rust-lang/futures-rs (main) score 89

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:32.160687+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 2026-08-29T17:51:17.329003+00:00, confidence not recorded.
  - readme: https://github.com/rust-lang/futures-rs (fetched 2026-08-28T04:09:32.160687+00:00, sha 260fb7aba3cb)
  - homepage: https://rust-lang.github.io/futures-rs/ (fetched 2026-08-29T08:46:42.461290+00:00, sha 21054567a136)
- Data as of 2026-08-30T08:39:29.467469+00:00.