Conquest is a real-time, multi-player space warfare game that was originally written in RATFOR for the VAX/VMS platform by Jef Poskanzer and Craig Leres in 1982. It was the early predecessor to Netrek.
Full source Archive 8.5 (stable) - intended primarily for Linux. See INSTALL for details. You need this to run your own servers. This will compile a GL client, ncurses client, server, conqoper and tools.