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DeepBrutePOS - An experimental chess program

What is it?

It's an experimental chess program. It is somewhat less experimental than Pos. DeepBrutePos is a brute-force, multithreaded chess engine. The experimental part will be the evaluation-routine. Based on the work of Claude Shannon with some of my ideas bolted on, taken from the previous incarnation of Pos.

It does the usual things like:


DeepBrutePos is called this way because:

  • Pos is short for Poseidon, the Greek god of horses (and a few other things)
  • deep: meaning that it is a multithreaded implementation. This is a reference to Deep Blue (by IBM) which was heavily multithreading and first to use the "deep" prefix.
  • brute: it uses brute force

You can see how it performs by checking this site. There, it continously battles against a couple of other chess engines.

How to run it?

The program has a couple of command line parameters. Invoke it with '--help' with a list and explanations.

In a terminal

When using the SUN Java 7.0 runtime environment, start it with "java -jar DeepBrutePos.jar --io-mode console".

Note: it is fully compatible with OpenJDK: development actually takes place with it.

UCI compatible board

DeepBrutePos as been verified to run with XBoard (yes) using the Polyglot UCI-to-Xboard adapter.
Start it with: "java -jar DeepBrutePos.jar --io-mode uci".


The program should fully support xboard/winboard. Start it with commandline "java -jar DeepBrutePos.jar --io-mode xboard".


The more processors/cores your computer has, the better: the speed-up seems to be linear upto about 6 cpu units.
It would be interesting for me if you would like to send me the speed of the program as it runs on your computer! Run the program with '--logfile mylog.txt' added to the command-line and mail it to me together with the specifications of your computer (cpu type, speed, etc.). Thanks in advance!


Please report all bugs/traps/etc. to mail@vanheusden.com. If possible, include a screendump and/or the logfile (start with '--logfile filename.log').

Download link:
DeepBrutePos-2.1.jarthis version played at the 45th CSVN tournament


I think it was around 1986 when I got intrigued by the game of chess and in particular chess on a computer. One of my best friends at that time (who unfortunately passed away) showed me a chess program on his MSX home-computer. I was amazed. I had such a computer too and one day I brought it with me and we let the two computers play against each other. It took hours (3.5MHz!) and, if memory serves me well, black won. I'm not entirely sure (my memory of that time is a little fuzzy) but I think it was Ultra chess by Aackosoft which got it all started.

While developing this program I received a lot of help from Sven Schüle. His help is invaluable!
Also thanks to the people at the talkchess.com forum for their help and patience.

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