What do you think about a GigaMeleeRumble?
I'll make a README sometime.
You compile with Maven through the roborumbleathome-pom module. You also need Robocode components pre-installed in your local repository. They are nowhere in any internet Maven repository. This is for compiling.
For running, you run a single coordinator instance, and as many worker instances as you have cores. You pass coordinator IP address through command line argument. Port is hard-coded at 1099 (RMI default). See the .bat files for an example.
Both coordinator and workers use the same configuration files as the official client, although they ignore some of the parameters.
It could be more configurable. But as it is, it is running fine for me so I stopped improving it for quite some time. Now that it is open source, feel free to contribute.
Early this morning I managed to get it to build.
As someone not used to Maven... I have to say... the experience of getting the Robocode components into a repository based on a download of the official robocode build, is an experience that really makes me dislike Maven. Things that ought to be very simple seem like quite a hassle with it.