Wildfire is always seeking contributors for documentation, programming, art, sound, taking YouTube videos and more. Interested in contributing to the development of 0 A.D.? More information on installation in other systems can be found on their website.
If you want to try the latest alpha version, you can also use the official PPA (for Debian and Ubuntu based distributions): sudo add-apt-repository ppa:wfg/0adĪnd then search for 0ad in the application menu.