Reactor BOM and legacy (2.x, 1.x)

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Starting from 3.0, Reactor is now organized into multiple projects:

Reactor Project

A set of compatible versions for all these projects is curated under a BOM ("Bill of Material").

Current Release Train

The first release train to follow the new and shiny BOM model will be Aluminium-RELEASE.

Using the BOM with Maven

In Maven, you need to import the bom first:


Notice we use the <dependencyManagement> section and the import scope.

Next, add your dependencies to the relevant reactor projects as usual, except without a <version>:


Using the BOM with Gradle

Gradle has no core support for Maven BOMs, but you can use Spring's gradle-dependency-management plugin.

First, apply the plugin from Gradle Plugin Portal (check and change the version if a new one has been released):

plugins {
    id "io.spring.dependency-management" version "1.0.0.RC2"

Then use it to import the BOM:

dependencyManagement {
     imports {
          mavenBom "io.projectreactor:reactor-bom:Aluminium-RELEASE"

Then add a dependency to your project without a version number:

dependencies {
     compile 'io.projectreactor:reactor-core'

BOM Versionning Scheme

The BOM can be imported in Maven, which will provide a set of default artifact versions to use whenever the corresponding dependency is added to a pom without an explicitly provided version.

As the different artifacts versions are not necessarily aligned, the BOM represents a release train with a codename-based versioning scheme: the usual MAJOR.MINOR numbers are replaced by a chemical name from the Periodic Table of Elements, in growing alphabetical order.

The first stable release is simply suffixed with -RELEASE, but the equivalent of patch releases are also possible as "Service Releases", appending the suffix -SR followed by the number of the service release (eg. -SR1, -SR2)


Join the initiative, fork, discuss and PR anytime. Roadmap is collaborative and we do enjoy new ideas, simplifications, doc, feedback, and, did we mention feedback already ;) ? As any other open source project, you are the hero, Reactor is only useful because of you and we can't wait to see your pull request mate !

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Detail of Projects

Reactor Core

Reactor Core

Reactive foundations for apps and frameworks and reactive extensions inspired API with Mono (1 element) and Flux (n elements) types

Reactor IPC

Reactor Core

Memory and InterProcessCommunication abstractions.

Reactor Netty

Reactor Netty

TCP and HTTP client and server.

Reactor Addons

Reactor Addons

Extra projects adding features to reactor:

  • reactor-adapter: adapt to/from various libraries, mainly RxJava 2.
  • reactor-test: test Flux, Mono and other Publisher...
  • reactor-logback: logback adapter for Flux/Mono log() feature.

Snapshot Artifacts

While Stable Releases are synchronized with Maven Central, fresh snapshot and milestone artifacts are provided in the repositories.

To add this repo to your Maven build, add it to the <repositories> section like the following:

        <name>Spring Snapshot Repository</name>

To add it to your Gradle build, use the repositories configuration like this:

repositories {
    maven { url '' }

You should then be able to import a BUILD-SNAPSHOT version of the BOM, like Aluminium.BUILD-SNAPSHOT.

Reactive Streams Commons

In a continuous mission to design the most efficient concurrency operators for Reactive Streams, a common effort -codename Reactive Streams Commons- has begun. Reactor is fully aligned with RSC design and is directly inlining RSC within its stable API contract scoped under reactor-core. Reactive Streams Commons is a research effort shared with everyone and is demanding of efficient stream processing challengers, therefore it is naturally decoupled of any framework noise.