We are following the Linux model of releases, where an even second digit of a release number indicates a "stable" release and an odd second digit indicates a "development" release (e.g., 3.0.x is a stable release and 3.1.x is a developmental release). If you are using a developmental release, there may be new features, but it is entirely possible that these features will be transient and/or unstable, and backward compatibility of the API and/or models is not guaranteed. If you require stability for teaching or deployment in applications, it is best to use a stable release of Weka.

Source code repository

Weka's source code for a particular release is included in the distribution when you download it, in a .jar file (a form of .zip file) called weka-src.jar. However, it is also possible to read source code directly from the Subversion source code repository for Weka, and there is also web-based access to the repository.

If you like to use Git rather than Subversion for software development, there is a Git mirror of the Subversion repository's branch for Weka 3.8 and a corresponding one for the main development trunk of Weka. Note that these mirrors are read-only, and we continue to use Subversion to commit changes to the software, not Git.

Code credits

The Weka developers would like to thank The MathWorks and the National Institute of Standards and Technology (NIST) for developing the Jama Matrix package and releasing it to the public domain, and to CERN (European Organization for Nuclear Research) for statistics-related code from their Jet libraries (now part of COLT).

The core Weka distributions include third-party library code from the MTJ project for fast matrix algebra in Java, the Java CUP project for generating parsers, the authentication dialog from the Bounce project, and the Apache Commons Compress library. For more information, see the lib folder of the source code repository.

Weka, including the early non-Java predecessors of Weka 3, was developed at the Department of Computer Science of the University of Waikato in Hamilton, New Zealand. Most of Weka 3 was written by Eibe Frank, Mark Hall, Peter Reutemann, and Len Trigg, but many others have made significant contributions, in particular, Remco Bouckaert, Richard Kirkby, Ashraf Kibriya, Xin Xu, and Malcolm Ware. For complete info on the contributors, check the Javadoc extracted from the source code of Weka, which is part of the available documentation.

Weka's package manager provides access to a large collection of optional libraries, many of which have been contributed by developers from other institutions. For information on the authors of these packages and the third-party libraries used within those Weka packages, please consult the Javadoc for the relevant package and the corresponding package lib folder.