ScaleCube is a lightweight decentralized Microservices and cluster membership library features; failure detection, messaging and gossip protocol for the Java VM
Latest commit 0b8699b Jan 16, 2017 @antonkharenko antonkharenko committed on GitHub Issue #171: Binding transport to IPv6 address causes (#173)
* Issue #171: Binding transport to IPv6 address causes

* Re-run test

* Increase sync timeout to avoid failed tests on Travis due to sync timeout


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ScaleCube, the art of scaling, in microservice architecture scalecube is a strategy in which components can scale on X, Y, Z axis. ScaleCube project provides the tools to develop, test and scale microservice components in distributed manner with ease.

The project focuses on ensuring that your application realises the full potential of the Reactive Manifesto, while delivering a high productivity development environment, and seamless production deployment experience.

Web Site:


ScaleCube is designed as an embeddable library for the Java VM. It is built in a modular way where each module independently implements a useful set of functionality and provides foundation for higher level features by abstracting away lower level concerns.

Next is described modules in the top to bottom order from the higher level features to the low level components.


ScaleCube Services provides a low latency Reactive Microservices library for peer-to-peer service registry and discovery based on gossip protocol ad without single point-of-failure or bottlenecks.

User Guide:


ScaleCube Cluster is a lightweight decentralized cluster membership, failure detection, and gossip protocol library. It provides an implementation of SWIM cluster membership protocol for Java VM. It is an efficient and scalable weakly-consistent distributed group membership protocol based on gossip-style communication between the nodes in the cluster. Read my blog post with distilled notes on the SWIM paper for more details.

It is using a random-probing failure detection algorithm which provides a uniform expected network load at all members. The worst-case network load is linear O(n) for overall network produced by running algorithm on all nodes and constant network load at one particular member independent from the size of the cluster.

ScaleCube Cluster implements all improvements described at original SWIM algorithm paper, such as gossip-style dissemination, suspicion mechanism and time-bounded strong completeness of failure detector algorithm. In addition to that we have introduced support of additional SYNC mechanism in order to improve recovery of the cluster from network partitioning events.

Using ScaleCube Cluster as simple as few lines of code:

// Start cluster node Alice as a seed node of the cluster, listen and print all incoming messages
Cluster alice = Cluster.joinAwait();
alice.listen().subscribe(msg -> System.out.println("Alice received: " +;

// Join cluster node Bob to cluster with Alice, listen and print all incoming messages
Cluster bob = Cluster.joinAwait(alice.address());
bob.listen().subscribe(msg -> System.out.println("Bob received: " +;

// Join cluster node Carol to cluster with Alice (and Bob which is resolved via Alice)
Cluster carol = Cluster.joinAwait(alice.address());

// Send from Carol greeting message to all other cluster members (which is Alice and Bob)
carol.otherMembers().forEach(member -> carol.send(member, Message.fromData("Greetings from Carol")));

You are welcome to explore javadoc documentation on cluster API and examples module for more advanced use cases.


ScaleCube Transport is a network communication layer which provides high throughput and low latency peer-to-peer messaging. It is based on Netty asynchronous networking framework and is using RxJava in order to provide convenient reactive API on top of network handlers pipelines.

Using ScaleCube Transport as simple as few lines of code:

// Bind first transport to port 5000
TransportConfig config1 = TransportConfig.builder().port(5000).build();
Transport transport1 = Transport.bindAwait(config1);

// Make first transport to listen and print all incoming messages

// Get 'host:port' address of the first transport
Address address1 = transport1.address(); 

// Bind second transport on available port and send message to the first transport
Transport transport2 = Transport.bindAwait();
transport2.send(address1, Message.fromData("Hello World"));

You are welcome to explore javadoc documentation on transport API for more advanced use cases.


For improvement requests, bugs and discussions please use the GitHub Issues or chat with us to get support on Gitter.

You are more then welcome to join us or just show your support by granting us a small star :)


Binaries and dependency information for Maven can be found at

To add a dependency on ScaleCube Services using Maven, use the following:


To add a dependency on ScaleCube Cluster using Maven, use the following:


To add a dependency on ScaleCube Transport using Maven, use the following:



  • Fork (and then git clone
  • Create a branch (git checkout -b branch_name).
  • Commit your changes (git commit -am "Description of contribution").
  • Push the branch (git push origin branch_name).
  • Open a Pull Request.
  • Thank you for your contribution! Wait for a response...


Apache License, Version 2.0