This site contains the documentation that is relevant to older WSO2 product versions and offerings.
For the latest WSO2 documentation, visit https://wso2.com/documentation/.

Working with the Source Code

The source code of WSO2 Message Broker as well as all other WSO2 products are maintained in GitHub repositories. If you are a developer, you can clone the source code from these Git repositories, and if required, you can do modifications and build a customized product on your own. WSO2 invites interested parties to contribute their changes and suggestions to WSO2. 

See the documentation on working with the source code for more information.