Crafty is a chess program written by UAB professor Dr. Robert Hyatt. It is directly derived from Cray Blitz, winner of the 1983 and 1986 World Computer Chess Championships. Crafty is a very strong chess engine: its ELO rating is about 2600 on a 256MB Athlon with 1,200 MHz [1].

Crafty board implementation is internally based on bitboards, 64-bit data structures. The source code of Crafty, written entirely in ANSI C, is available for free, so any computer chess enthusiast can take a look at it. Crafty uses negascout search, killer move heuristics, static exchange evaluation, quiescence search, and pruning, hash tables (transposition/refutation) as well as evaluation caches, selective extensions, recursive null-move search, and many other features (cf manual).

Crafty uses the XBoard protocol, and can also be run with the popular free chess interfaces WinBoard or Arena.

Furthermore, there are special editions, CraftySE, which allow a huge number of settings. Used with opening books, position learning function and important endgame table bases they play with a human style even on low amateur levels. This is what makes Crafty so popular.

In the World Computer Chess Championships 2004 Crafty won the fourth place with same amounts of points as the third place finisher, Fritz 8.

Crafty is one of the programs included in the SPEC-CPU benchmark test. It is also included as additional engine in Fritz.

External links

• Crafty on ftp server
• rpm file for linux