Home Downloads The Joker Chess Engine Project Goal Joker is my newest Chess engine. It is an experimental engine: I am developing it for the purpose of trying out novel techniques, that are not commonly applied in other engines.

Areas of interest are:

• Move ordering in Quiescence Search
• Combining depth-first with breadth-first search algorithms
• Generalizing null-move pruning to other moves
• Minimax search with interval arithmetic
• Deep futility pruning
• Hash-replacement algorithms
• Refutation tables
• Differentially maintained attack tables
• Differential Pawn-structure evaluation

The project is in its infancy: The first version of Joker that could play a full game was born October '06. At that point it was still a quite conventional engine, mostly differing from other engines through the fact that many standard features (e.g. the killer and history heuristic) had not yet been implemented. The evaluation function at that point was also rather rudimentary (TSCP-like). The only non-standard features that were implemented was the way Internal Iterative Deepening was performed, in combination with "depth-awareness" of the various search lines, and the "equi-distributed draft" hash-replacement scheme.

So there is not very much to report on these pages, but in the future I hope this will change!