Kreveta 2.3.0 - new version chess engine

Kreveta - UCI chess engine

Author: Zlomený Měsíc

Kreveta 2.3.0 what's new?

Yet another Kreveta release, this time bringing many improvements and new features:

• Adjustable playing strength (800-2200 Elo)

  • Kreveta now features an internal Elo system. The Elo level is set using the UCI_Elo option, and activated using the UCI_LimitStrength option. The system has been calibrated on latest CCRL ratings, meaning you're not going to be guessing the real strength (unlike with Stockfish).
  • The Elo limit introduces deterministic noise in static evaluation and restricts deep mate paths, therefore the playing style should accurately reflect human-like beginner behavior. Kreveta won't blunder a queen in one move, but will be positionally weaker.

• More UCI options

  • Clear hash of type button has been added, allowing erasing all data from the transposition table during search.
  • UsePerftHash enables/disables the usage of the hash table designated for Perft. This may be useful in cases where genuine move generation speed is preferred over node counts.
  • UCI_AnalyseMode essentially acts against the command ucinewgame.

• Fewer hardware limitations

  • Previously, Kreveta could only run on processors supporting the AVX2 and BMI2 instruction sets. This release adds fallbacks (although obviously slower), which allow running Kreveta on virtually any modern hardware (credit @KryKomDev).

• Search improvements

  • PieceToHistory has been implemented, storing data of advantageous and beneficial piece placement, which is then used to further order captures.
  • Correction logic has changed a lot, primarily with the removal of king corrections.
  • A separate hash table (SETT) is now used to store purely static evaluations of positions, later allowing lookups instead of repeated computations.
  • The amount of heap allocation in hot paths has been drastically reduced, mainly by using pre-allocated tables/pools for NNUE accumulators and principal variation arrays in search.

• Other

  • The eval command now divides individual components of static evaluation and prints their respective contributions in a comprehensive way, neatly organized into a table.
  • The classical part of static evaluation (HCE) now considers more aspects of the position, such as king-pawn distance, backward pawns, overextended pawns, unopposed supported or phalanx pawns, and bishop pairs.
  • Static Exchange Evaluation (SEE) is now also used to evaluate quiet moves.
  • A few bugs have been fixed.

Playing strength improvements against Kreveta 2.2.5:

STC 8+0.15s

Elo   | 72.8 +/- 8.4
Games | total: 5000, W: 2391, L: 1358, D: 1251
Score | 0.603, LOS: 100.0 %, draw ratio: 25.0 %

Kreveta 2.2.3 vs other engines:

Critter 1.6a	0/6	-6	6 games
Priessnitz 2.0.1 JA	0/5	-5	5 games
Human Chess Engine 0.1 JA	4/4	+4	4 games
Maxima 2.0.0 JA	1/4	-2	4 games
Vantage 1.3.0	0.5/4	-3	4 games
Petrel 3.3 JA	0.5/4	-3	4 games
Stockfish 18	0/4	-4	4 games
Tarnished 5.0	0/4	-4	4 games
Stockfish 18 JA	0/4	-4	4 games
Sturddle 2.5.0	0/4	-4	4 games
Odonata 1.1.0	0/4	-4	4 games
Bagatur 5.4	0/4	-4	4 games
Clockwork 20260203	0/4	-4	4 games
Zangdar 6.1	0/4	-4	4 games
Halogen 15.33.3	0/4	-4	4 games
PZChessBot 6.1	0/4	-4	4 games
DON dev-20260204	0/4	-4	4 games
VietCoffee 1.0.8 JA	3/3	+3	3 games
SoloEngine 1.3.1	1.5/2	+1	2 games
Vantage 1.03.0	1/2	+0	2 games
Zangdar 6	0/2	-2	2 games

Kreveta 2.3.0 download