Crafty is a state-of-the-art computer chess program. It is full-featured, plays a good game of chess, and source code is freely available.
Release Notes: Many changes since the last update.
Release Notes: There have been changes to the outside passed pawn and outside candidate pawn code to more correctly recognize when one side has a simple endgame position that is easy to win. Futility pruning and razoring has been added.
Release Notes: In this release, there has been a significant change to the search extension limits, a minor tweak to reduce the time limit by 1/4 for ponder=off games was made, a fix to correctly realize that KR[BN] vs KRR is a draw for the KRR side if it doesn't have at least a pawn left was made, and other minor fixes and improvements have also been made.
Release Notes: A change in endgame draw recognition to handle the case where one side appears to be in a lost ending but is stalemated, and a minor evaluation change to notice that K+B+right RP vs K+B is not necessarily won if the weaker side has a bishop of the right color.
Release Notes: A fix to book-learning to make it much more aggressive.