# mxcl/PromiseKit

Promises for Swift & ObjC.

Repository: https://github.com/mxcl/PromiseKit
Canonical: https://ross.abutalabs.com/products/promisekit
Language: Swift
License: MIT
License Family: permissive
Topics: swift, objc, promises
Last push: 2026-06-03T18:37:03+00:00

## Health v2 (maintenance only)
Score: 61/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 85, release rhythm 8, longevity 100
- inputs: {"age_days": 4534, "days_push": 91, "days_rel": 594, "gap_med": null, "n_releases_24m": 1}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 14227, forks 1456 (observed 2026-08-28T04:11:06.472786+00:00)

## What it is
PromiseKit is a Swift and Objective-C library implementing promises to simplify asynchronous programming. It supports iOS, macOS, tvOS, watchOS, Linux, and Android with CocoaPods, Carthage, and SwiftPM integration.

## Use cases
- handle async network requests in Swift
- avoid callback hell in iOS apps
- combine multiple async tasks with when()
- chain asynchronous operations with error handling
- write readable async code in Objective-C

## When to choose
- you're on Swift 5.4 or earlier without async/await
- you need Objective-C bridging for promises
- you maintain legacy iOS/macOS codebases using CocoaPods

## When to avoid
- you're using Swift 5.5+ where async/await is built in
- you're starting a new project with modern Swift concurrency
- you need a cross-language async runtime outside Apple platforms

## Facets
- artifact type: library
- maturity: maintenance
- function: concurrency, error-handling
- domain: developer-tools, mobile-development, cross-platform
- platform: cross-platform
- tags: promises, async, objective-c, futures, cocoapods, swift, ios, macos, linux

## Member repositories
- mxcl/PromiseKit (main) score 61

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:06.472786+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 2026-08-29T17:12:43.361661+00:00, confidence not recorded.
  - readme: https://github.com/mxcl/PromiseKit (fetched 2026-08-28T04:11:06.472786+00:00, sha 44e50382c5f4)
- Data as of 2026-08-30T08:39:29.467469+00:00.