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Overview
Nimble is a matcher framework for Swift and Objective-C. It expresses value, collection, boolean, and asynchronous expectations using expect(...).to(...), making XCTest and Swift Testing failures easier to read.
Features and best fit
Based on official documentation; not hands-on tested · Content checked:
Key features
Express values, collections, and conditions through matchers
Matchers such as equal, beCloseTo, contain, and beTruthy provide a readable vocabulary for expectations. Nimble can be used with Quick or directly from a test target.
Sources: [2]
Use polling expectations such as toEventually for asynchronous state
Polling expectations validate values that change asynchronously. Version 14.0.0 reimplements polling by calculating the number of attempts first, aiming to remove a source of flakiness under heavily loaded CI and parallel testing.
Best fit
Fits XCTest or Swift Testing suites that want domain-readable assertions
It is useful when values, collections, and asynchronous state should use reusable matchers with clearer intent and failure messages than ad hoc assertions.
Sources: [2]
Before adoption
Nimble 14 deprecates synchronous polling APIs and belongs only in test targets
Version 14 deprecates synchronous Swift polling expectations and synchronous waitUntil in favor of async APIs. The README also says to link Nimble to the unit test target, not the app target. Package.swift uses Swift tools 6.0 and declares iOS 13+.
Official sources
- [1]Quick/Nimble — GitHub repository(2026-10-06)
- [2]Nimble v14.0.0 — README(2026-10-06)
- [3]Nimble v14.0.0 — Package.swift(2026-10-06)
- [4]Nimble v14.0.0 release(2026-10-06)
- [5]Nimble Apache-2.0 license(2026-10-06)
Supplemental curator note
Nimble fits XCTest and Swift Testing suites that want readable matcher-based assertions. Version 14 deprecates synchronous polling expectations, so existing suites should identify migrations to async APIs.
Try it in 3 steps
- 1
Add Nimble 14.0.0 as a test dependency
Add Nimble only to the unit test target. Version 14.0.0 supports iOS 13+.
.package(url: "https://github.com/Quick/Nimble.git", exact: "14.0.0") - 2
Assert values with expect and matchers
Follow the README examples and express value and string expectations through matchers.
import Nimble expect(1 + 1).to(equal(2)) expect("seahorse").to(contain("sea")) - 3
Wait for asynchronous state with polling
Use the async polling form because Nimble 14 deprecates synchronous Swift polling expectations.
await expect { state.isReady }.toEventually(beTrue())
Growth
Growth trends · Last 30 days
4,836 Stars
Trend data is still being collected.
Development activity
Last 90 days · weekly
- Commits (last 30 days)
- 0
- Open PRs
- 10
Development activity is still being collected.
Built with
Categories and tags
Categories
GitHub data
GitHub dataView detailed GitHub data
GitHub Topics
- matcher-functions
- swift-generics
- swift-assertions
- failure-messages
- asynchronous-expectations
- swift
- testing
- operator-overloads
- bdd
- Stars
- 4,836
- Forks
- 607
- Watchers
- 85
- Open issues
- 20
- Contributors
- 117
- Owner type
- Organization
- Primary language
- Swift
- License
- Apache-2.0
- Repository last updated
- May 4, 2026
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