GNU Backgammon

GNU Backgammon (gnubg) is a software that plays and analyzes backgammon games and matches. Despite being a work-in-progress, gnubg has a range of features that make it a valuable tool for backgammon enthusiasts. It can play both independent games and tournament matches, evaluate and roll out positions, tune its own evaluation functions using either TD or supervised training, maintain databases of positions for training and other purposes, among other things.

Gnubg is designed to be driven by a command-line interface and displays an ASCII rendition of a board on text-only terminals. However, it also supports a GTK+ board window where available, providing users with a graphical option for playing games and manipulating positions. The software is extensible on platforms that support Guile and/or Python.

Currently, gnubg plays at the level of a championship flight tournament player, which rates at around 2000 on FIBS. However, it's gradually improving, and should be somewhat stronger than this when released. Users can also play gnubg at numerous other online backgammon servers.

Some of the key features of gnubg include tournament match and money session cube handling, a command-line interface, support for a GTK+ interface with a graphical board window or a rough ASCII representation of a board on text terminals, functions to generate legal moves and evaluate positions at varying search depths, neural net functions for giving cubeless evaluations of all other contact and race positions, among others.

Gnubg also supports both 1-sided and 2-sided bearoff databases, automated rollouts of positions, TD(0), and supervised training of neural net weights. Position databases for supervised training are also supported. Users can load and save .sgf games and matches, export games and matches to HTML, LaTeX, .mat, PDF, PNG, PostScript, and plain text formats.

Importing .bkg, .mat, .pos, .sgg, .tmg, and FIBS "oldmoves" files is also possible. Gnubg boasts scripting ability if Guile or Python is available. The software's automatic and manual annotation feature provides analysis and commentary for games and matches, and keeps record statistics of players in games and matches (both native inside gnubg and externally using relational databases and Python). Lastly, gnubg has native language support in 10 languages, including cs_CZ, da_DK, en_GB, en_US, fr_FR, de_DE, is_IS, it_IT, ja_JP, and tr_TR.