FruiT 2.3.1

Logo Name VN Authors Country


 Fruit 2.3.1

Fabien Letouzey

Ryan Benitez







Own Book

32bits 64bits


Multi Level








X X      

2800 +

Engine Language : C++
First release :  
Last update: July 2007
Open source: yes (for 2.1)
Link : Fruitchess / Free version Fruit 2.1: WBEC

 Fruit (compilations by Bryan Hofmann !)

Opening Book 

.pgn :

Link to Performance.bin from Marc Lacrossse  look under download


Download: Last update :

 FRUIT 2.3.1   FRUIT 2.3.1MAC

Here are the Windows and Mac versions of Fruit 2.3.1 also. 
I did not change the default UCI settings because I did not want to change the style of play from 2.3 as the focus is on minor bug fixes.  However some mate in X moves situations where Fruit misses the check mate can be fixed by setting Extend Checks to True.  I expect Fruit to play better over all with this option set to true but so far this is untested. 



 Fruit 2.3

Include Fruit 2.3 (including Beta versions 070327, 061115a, and 061115b)

All compilation by Bryan Hofmann



Here is the Linux version of Fruit 2.3.1 with minor bug fixes and a UCI option to extend checks.  Windows and Mac versions coming soon. 



More uci option :  
Comment: From The read me file

This software is provided as-is with not warranty implied or otherwise. Some of the options are untested and my not be working as intended. Feel free to report bugs (other than that Fruit lost) to
The Play Style option “Gambit” is not working at this time and will use the “Very-Aggressive” setting instead when this is set. I am unlikely to go back and finish this in Fruit. I had the theory in place but did not have time to implement this idea that is questionable at best as to how well it could work. The idea is that if a king attack is above ATK_Margin and you are down on material score then compensate a percent based on king attack- ATK_Margin back to the material score up to MAT_Loss_CAP. ATK_Margin and MAT_Loss_CAP are of course variable to be set. I came up with this idea not as something to make a program play stronger but to make it play some exciting sacrificing moves that it otherwise would not have.

Some of the UCI options
Play Style: this affects king attack and level.
Pawn Shield Hard: This affects the penalty for defects in pawn shielding.
Pawn Shield Soft: This affects the penalty of defects in pawn shielding as it is combine with penalties given for your king being attacked.
Use PPP: This is a bonus for having more pieces available for advancing your passed pawn then the opponent has available for stopping it.
PPExt: This is a passed pawn extension. I think it is good but I turned it off when I was testing with no search extensions in main search.

I am sure I missed a lot. Fruit is programmed by Fabien Letouzey. Thank you to every one in the computer chess community including but not limited to Robert W. Allgeuer, Omar Skulason, Roger Brown, Bryan Hofmann, Tord Romstad, Tom Likens, Wilhelm Hudetz, Dann Corbit, Leo Dijksman, Heinz van Kempen, Joachim Rang, Nolan Denson, Mircea Hrubaru, Marc Lacrosse, Thorsten Czub, Aaron Gordon, Salvo Spitaleri, Daniel Mehrmann and so many more.

Thanks for using Fruit and I hope you enjoy.



 Last updated 08/02/07