Xelf is a simple 2-D game engine written in Common Lisp. Along with a Common Lisp compiler such as Steel Bank Common Lisp, Xelf can be used to write games that compile from a single codebase into optimized native executables for Windows, Mac, and GNU/Linux.

Xelf is a work in progress, but has been used to create several fun games, including 2x0ng and 3x0ng. Please see the user documentation for more info.

Xelf is Free Software, licensed under the GNU LGPL v3, and requires only Free Software to run. With the use of SBCL and Wine, Lisp games for Windows can be cross-compiled from GNU/Linux using only Free Software. All this combined with the ability of SBCL to make binaries for GNU/Linux and Mac OSX when running on those platforms, makes it possible to create Common Lisp games, animations and other multimedia projects and deliver them to a wide audience without using any proprietary programs. This is important for games-as-speech, for if a game is to count as an act of truly free expression, both its creators and its players must be free of proprietary restrictions insofar as they meet together in the experience.

Please also visit our friends at the lisp games wiki to find out more about the use of Lisp in games.

• Work-in-progress programmer's guide.
• "3x0ng" is a recent game made with Xelf. See the 3x0ng page.
• Xelf source code repository at gitlab
• the lisp games wiki
• irc.freenode.org, channel #xelf
• author's home page