# google/promises

Promises is a modern framework that provides a synchronization construct for Swift and Objective-C.

Repository: https://github.com/google/promises
Canonical: https://ross.abutalabs.com/products/google-promises
Language: Objective-C
License: Apache-2.0
License Family: permissive
Topics: promises, futures, objective-c, swift, library, framework
Last push: 2026-06-09T16:52:03+00:00

## Health v2 (maintenance only)
Score: 89/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 86, release rhythm 87, longevity 100
- inputs: {"age_days": 3148, "days_push": 85, "days_rel": 85, "gap_med": 0, "n_releases_24m": 2}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 3829, forks 314 (observed 2026-08-28T04:08:23.121067+00:00)

## What it is
Google's Promises is a framework providing a synchronization construct for Swift and Objective-C to simplify writing asynchronous code. It offers promise/future semantics with chaining, error handling, and combinators like All, Race, and Retry.

## Use cases
- write async code in Swift without callback nesting
- chain asynchronous operations with then/catch
- wait for multiple async tasks to complete
- add timeouts and retries to async operations
- interoperate promises between Objective-C and Swift

## When to choose
- you're building iOS/macOS/tvOS/watchOS apps in Swift or Objective-C
- you need promise/future semantics with ObjC-Swift interop
- you want battle-tested async utilities like retry, race, and timeout

## When to avoid
- you're using Swift concurrency (async/await) exclusively
- your project is not on Apple platforms
- you need promises in JavaScript, Python, or other languages

## Facets
- artifact type: library
- maturity: stable
- function: concurrency, developer-tools
- domain: developer-tools, cross-platform
- platform: cpp
- tags: promises, futures, objective-c, swift, asynchronous-programming, apple-platforms, macos, ios

## Member repositories
- google/promises (main) score 89

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:08:23.121067+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 2026-08-29T18:26:20.332067+00:00, confidence not recorded.
  - readme: https://github.com/google/promises (fetched 2026-08-28T04:08:23.121067+00:00, sha 6727e85b0920)
- Data as of 2026-08-30T08:39:29.467469+00:00.