You can get the source code from github. Inside a terminal type:
git clone --recurse-submodules https://github.com/godlikepanos/anki-3d-engine.git anki
All the information of how to build the engine are located inside the docs directory.
**WARNING**: Some times the master branch may not compile. Also note that without the assets (not published yet) the test application will crash. I’m working to address these issues.