Axon 4.0 was released on October 18, 2018 as the successor to Axon Framework 3.*. The name change from "Axon Framework" to "Axon" is intentional: starting from 4.0, Axon is not just a framework, but a complete platform consisting of both Axon Framework and Axon Server.
While many types of applications can be built using Axon, it has proven to be very popular for microservices architectures. Many of the recent changes to Axon have been made with this use case in mind.
Please visit the AxonIQ website to learn more about AxonIQ and the Axon community. There, you will find information about Axon training, support options, upcoming and past events.
With this guide, we aim to provide all the information you need to create and customize a software for your organization’s needs.
The Axon platform consists of Axon Framework and Axon Server. It is provided by AxonIQ B.V. under the licenses described below.
Axon Framework, as well as the Axon documentation and sample programs, are open source and provided under the Apache License v2.0.
For Axon Server, licensing depends on the version.
The standard version, called "Axon Server", is open source and free to download and use. It is provided under an AxonIQ-specific open source license. While this license allows you to run the software freely in any environment, it is less permissive than the Apache License. For instance, it doesn't allow you as a licensee to create a derivative work.
The commercial version, called "Axon Server Enterprise", as well as the various "Packs", are closed source and provided under a commercial license agreement.