The LIXA project is hosted both on GitHub.com and SourceForge.net portals. GitHub.com is mainly intended for system software developers that need to access, change and share the source code with the project. SourceForge.net is mainly intended for system engineers that need to download and install the software.
The source code that can be fetched using git typically contains the last commit: there's no guarantee that every commit contains stable software, sometimes it can be intermediate work that does not compile. Every release is explicitly tagged.
The tarball that can be downloaded by SourceForge.net is a release that has passed some sort of test and should compile and run flawlessly. Even releases are associated to stable software and odd releases are associated to testing software with new features.