Wisdom is knowing how

   little we know -- Socrates

About Company

Started in 1980, retired in 2004 REBEL was baptized into ProDeo, latin for gratis according to Dutch tradition.

Other Information


   ProDeo 1.8 series



    ProDeo 1.7 series



    Older versions




ProDeo (version 1.87)  approximately 2700 ELO   Size 4 Mb

Download ProDeo 1.87


Install the self-extracting archive into a folder of your choice.


To run ProDeo you will need to announce the engine first.


Under Chessbase this means: Engine -> New UCI engine -> Browse -> RebelUCI.exe

Under ARENA do: Engines -> New Engine -> UCI -> RebelUCI.exe

Under ChessPartner do: Extra -> Engine Import Wizard -> Winboard -> Install -> ProDeo.exe


ARENA is freeware and can be downloaded here.



Release Notes 1.87

December 17, 2013


This version is the result of a new test methodology as described on the engine tuning page (Part II) using "Nodes" testing as a base. Using self-play it shows a considerable increase of playing strength and to our surprise the scaling at increasing time controls is excellent.


1.87 vs 1.86




Run Time




8 hours

 40 moves in 15 seconds



28 hours

 40 moves in 30 seconds



21 hours

 40 moves in 60 seconds



27 hours


As it seems we have created ourselves a more reliable testing method as with 16.000 games (or 32.000 for that matter) we can now measure 1-2 elo improvements in a much faster setting.



Changes (technical)


  1. Added knowledge to King Safety (approx 4 elo)
  2. Added LMP (late move pruning) (approx 10 elo)
  3. Null windowing in aspiration search (approx 2 elo)
  4. Restored the [Right to Move = 100] parameter (approx 12 elo) This "tempo penalty" suddenly works a lot better now that we moved to full Nullmove search.
  5. Added a second condition to the tempo pernalty namely, subtract 10% from the mobilty score. Its reason is found on the logic that mobility often is a temporarily advantage that can be undone by a couple of moves and sometimes even by the next move (approx 10 elo).
    The 10% was an educated guess that worked quite well from the start but needs some serious tuning plus (perhaps) a maximum to the penalty. Furthermore what's on the menu for a next version is to include a similar correction for King Safety and Passed Pawns. Like Mobility they often produce big scores while sometimes much of it is undone by the next move.
  6. Some code speed-up (approx 1-2 elo)






 Chess program  Ed Schröder
 Opening Book  Jeroen Noomen
 Winboard support  Lex Loep
 UCI Interface  Odd Gunnar Malin
 KPK code  Don Dailey


Programmer code (ideas taken from external sources)


 ProDeo 1.6  Fruit 2.1  eval.cpp line 1023  Penalty for caught bishops on the 6th row.
 ProDeo 1.6  Fruit 2.1  eval.cpp line 1063  Free rook in case of lost castling rights.
 ProDeo 1.8  Stockfish 2.11  evaluate.cpp line 192

 Added the principle of safe_queen_checks to

 King Safety.



Copyright ® 2013  Ed Schröder