About


Chiron is a very strong chess program, the current Italian Computer Chess Champion.
It supports both UCI and Winboard 2 protocols. Work on Chiron started in the fall of 2002 and it has been under continuous development ever since. When it debuted at the Italian Computer Chess Championship in June 2003, it was a rather weak Winboard engine with a playing strength of about 2100 Elo points. Its strength grew over the years, it started to arrive consistently second at the italian tournaments and reached good ratings in the various rating lists. In 2006 support of UCI protocol was added. At the beginning of 2007, it had a rating of about 2700 and 2650 Elo points on the CCRL and CEGT rating lists, respectively. Starting from february 2009, having lost the source code of the latest development version and wanting to implement bitboards, it underwent a major rewrite. In November of the same year it won its first italian championship and won it again in 2010, 2016, 2017, 2018 and 2019. Chiron played in four World Championships: Torino 2006, Leiden 2017, Stockholm 2018 and Macao 2019. Its best results were 2nd places in the 2019 WCCC and WSCCC. A modified version of Chiron was used in the 2014 video game Watch Dogs by Ubisoft.

In these years Chiron has improved a lot thanks also to ideas found in strong open source engines, computer chess fora, papers and websites. In particular I would like to thank Fabien Letouzey, the Stockfish team, the Ippolit guys, Bruce Moreland, Robert Hyatt, Ernst Heinz, Ed Schröder and many others. Thanks to Miguel Ballicora, Eugene Nalimov, Daniel Shawul and Ronald de Man for the probing code of their tablebases/bitbases, to Pradu Kannan, Gerd Isenberg (thanks also for the tremendous work done on the Chess Programming Wiki) and Lasse Hansen for the magic bitboards, to Michel Van den Bergh for the Polyglot specifications, to “Sesse” and Stephan Vermeire for the CTG specifications, to Ilari Pihlajisto for cutechess-cli that I’ve been using since 2009 for testing Chiron. Thanks to all the people that tested Chiron in the past, among them Ciro Vignotto, Leo Dijksman, Olivier Deville, Günther Simon, Lars Hallerström, the testers of CEGT and CCRL and many others. Thanks to Wilhelm Hudetz for the logo. Thanks to Luca Lissandrello for everything he has done for the italian computer chess community. Finally, thanks to Salvo Spitaleri and Arturo Ochoa for their opening books.
Thanks to Paolo Casaschi for pgn4web, used in this site.