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Library support for Kotlin coroutines. This is a companion version for Kotlin 1.1.4 release (this is the minimal required Kotlin runtime version).


  • core – core primitives to work with coroutines:
    • launch, async, produce, actor, etc coroutine builders;
    • Job and Deferred light-weight future with cancellation support;
    • CommonPool and other coroutine contexts;
    • Channel and Mutex communication and synchronization primitives;
    • delay, yield, etc top-level suspending functions;
    • select expression support and more.
  • reactive – modules that provide builders and iteration support for various reactive streams libraries:
    • Reactive Streams, RxJava 1.x and 2.x and Project Reactor.
  • ui – modules that provide coroutine dispatchers for various single-threaded UI libraries:
    • Android, JavaFx, and Swing.
  • integration – modules that provide integration with various asynchronous callback- and future-based libraries.
    • JDK8 CompletableFuture, Guava ListenableFuture, and synchronous networking/IO.


Using in your projects

Note that these libraries are experimental and are subject to change.

The libraries are published to kotlinx bintray repository, linked to JCenter and pushed to Maven Central.


Add dependencies (you can also add other modules that you need):


And make sure that you use the latest Kotlin version:



Add dependencies (you can also add other modules that you need):

compile 'org.jetbrains.kotlinx:kotlinx-coroutines-core:0.19.2'

And make sure that you use the latest Kotlin version:

buildscript {
    ext.kotlin_version = '1.1.51'


In obfuscated code, fields with different types can have the same names, and AtomicReferenceFieldUpdater may be unable to find the correct ones. To avoid field overloading by type during obfuscation, add this to your config:

-keepclassmembernames class kotlinx.** {
    volatile <fields>;
compile "org.jetbrains.kotlinx:kotlinx-coroutines:0.20-alpha-6"

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