kotlinx.coroutines

Library support for Kotlin coroutines with multiplatform support.
This is a companion version for the Kotlin 2.1.0 release.
suspend fun main() = coroutineScope {
launch {
delay(1000)
println("Kotlin Coroutines World!")
}
println("Hello")
}
Play with coroutines online here
Modules
- core — common coroutines across all platforms:
- core/jvm — additional core features available on Kotlin/JVM:
- core/js — additional core features available on Kotlin/JS:
- test — test utilities for coroutines:
- debug — debug utilities for coroutines:
- DebugProbes API to probe, keep track of, print and dump active coroutines;
- CoroutinesTimeout test rule to automatically dump coroutines on test timeout.
- Automatic integration with BlockHound.
- reactive — modules that provide builders and iteration support for various reactive streams libraries:
- Reactive Streams (Publisher.collect, Publisher.awaitSingle, kotlinx.coroutines.reactive.publish, etc),
- Flow (JDK 9) (the same interface as for Reactive Streams),
- RxJava 2.x (rxFlowable, rxSingle, etc), and
- RxJava 3.x (rxFlowable, rxSingle, etc), and
- Project Reactor (flux, mono, etc).
- ui — modules that provide the Main dispatcher for various single-threaded UI libraries:
- Android, JavaFX, and Swing.
- integration — modules that provide integration with various asynchronous callback- and future-based libraries:
Documentation
Using in your projects
Maven
Add dependencies (you can also add other modules that you need):
<dependency>
<groupId>org.jetbrains.kotlinx</groupId>
<artifactId>kotlinx-coroutines-core</artifactId>
<version>1.10.2</version>
</dependency>
And make sure that you use the latest Kotlin version:
<properties>
<kotlin.version>2.1.0</kotlin.version>
</properties>
Gradle
Add dependencies (you can also add other modules that you need):
dependencies {
implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.10.2")
}
And make sure that you use the latest Kotlin version:
plugins {
kotlin("jvm") version "2.1.0"
id "org.jetbrains.kotlin.jvm" version "2.1.0"
}
Make sure that you have mavenCentral() in the list of repositories:
repositories {
mavenCentral()
}
Android
Add kotlinx-coroutines-android
module as a dependency when using kotlinx.coroutines on Android:
implementation("org.jetbrains.kotlinx:kotlinx-coroutines-android:1.10.2")
This gives you access to the Android Dispatchers.Main
coroutine dispatcher and also makes sure that in case of a crashed coroutine with an unhandled exception that
this exception is logged before crashing the Android application, similarly to the way uncaught exceptions in
threads are handled by the Android runtime.
R8 and ProGuard
R8 and ProGuard rules are bundled into the kotlinx-coroutines-android module.
For more details see "Optimization" section for Android.
Avoiding including the debug infrastructure in the resulting APK
The kotlinx-coroutines-core artifact contains a resource file that is not required for the coroutines to operate
normally and is only used by the debugger. To exclude it at no loss of functionality, add the following snippet to the
android block in your Gradle file for the application subproject:
packagingOptions {
resources.excludes += "DebugProbesKt.bin"
}
Multiplatform
Core modules of kotlinx.coroutines are also available for
Kotlin/JS and Kotlin/Native.
In common code that should get compiled for different platforms, you can add a dependency to kotlinx-coroutines-core right to the commonMain source set:
commonMain {
dependencies {
implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.10.2")
}
}
Platform-specific dependencies are recommended to be used only for non-multiplatform projects that are compiled only for target platform.
JS
Kotlin/JS version of kotlinx.coroutines is published as
kotlinx-coroutines-core-js
(follow the link to get the dependency declaration snippet).
Native
Kotlin/Native version of kotlinx.coroutines is published as
kotlinx-coroutines-core-$platform where $platform is
the target Kotlin/Native platform.
Targets are provided in accordance with official K/N target support.
Building and Contributing
See Contributing Guidelines.