A new version of the chess engine has just been released – Bread Engine 2.0.0. Previous versions didn't break into the CEDR Top 64 chess engines and were ranked among amateurs. We'll see how this engine fares; the first tests will be held soon.
Bread Engine is a chess engine written in c++. It uses NNUE (efficiently updatable neural network) to evaluate positions, as well as minimax search. Bread engine does not have a GUI built in, however it supports the uci protocol, you can therefore run it on any chess GUI.
Author: Nonlinear2
What's new and key changes in the new version of the Bread Engine 2.0.0?
NNUE
Bread's neural network has been mostly rewritten. It was retrained from zero knowledge on 40 million games of self play, making Bread a "zero" engine.
More precisely, improvements include:
a modified architecture: 768x2 -> 1024x2 -> 1, trained on ~5 billion positions with 10 self play training iterations (~369 elo)
screlu activation for the feature transformer (~21 elo)
output buckets (~5 elo)
direct accumulator calculation (~30 elo)
a sped up L1 inference (~8 elo)
Main search:
use tt_capture for nmp reductions (~7 elo)
add continuation history pruning (~15 elo)
two SPSA tunes (~48 elo)
General improvements:
add support for the genfens command
fixed makefile executable extension for linux
improve threefold detection (~22 elo)
Improved Nonsense option
Bread features a uci option called Nonsense, which has been improved in this release. If the option is active, bread will:
play the bongcloud opening
print lyrics from "never gonna give you up" during search
take all of the opponent's pieces and promote all pawns to knights and bishops
Testing the Bread Engine 2.0.0 chess engine.
Progression tests results
STC: 8 + 0.08 s
Results of bread_engine_2.0.0 vs bread_engine_1.6.0 (8+0.08, 1t, 16MB, UHO_2024_8mvs_big_+115_+134.pgn):
Elo: 382.18 +/- 19.10, nElo: 618.97 +/- 15.23
LOS: 100.00 %, DrawRatio: 7.60 %, PairsRatio: 461.00
Games: 2000, Wins: 1666, Losses: 65, Draws: 269, Points: 1800.5 (90.03 %)
Ptnml(0-2): [0, 2, 76, 241, 681], WL/DD Ratio: 4.85
LTC: 40 + 0.4 s
Results of bread_engine_2.0.0 vs bread_engine_1.6.0 (40+0.4, 1t, 128MB, UHO_2024_8mvs_big_+115_+134.pgn):
Elo: 339.63 +/- 19.19, nElo: 552.46 +/- 17.58
LOS: 100.00 %, DrawRatio: 8.67 %, PairsRatio: 227.33
Games: 1500, Wins: 1188, Losses: 60, Draws: 252, Points: 1314.0 (87.60 %)
Ptnml(0-2): [0, 3, 65, 233, 449], WL/DD Ratio: 7.12
Thanks to a new neural network and many search improvements, Bread 2.0.0 is much stronger than version 1.6.0!
| Short time control (8 + 0.08 s) | +382 Elo |
| Long time control (40 + 0.4 s) | +340 Elo |
Bread Engine 1.6.0 vs other chess engines:
| Eubos 4.1 JA | 9.5/10 | +9 | 10 Games |
| Critter 1.6a | 5/10 | +0 | 10 Games |
| Eleanor 2.0 | 2.5/10 | -5 | 10 Games |
| Laser 1.8 beta JA | 3/8 | -2 | 8 Games |
| Fire 10 mingw | 1/8 | -6 | 8 Games |
| Artemis 17.9TR sl | 0.5/8 | -7 | 8 Games |
| Pawnocchio 1.8.1 | 0.5/8 | -7 | 8 Games |
| Patricia 5.0 | 0.5/8 | -7 | 8 Games |
| Cinder 0.3.1 | 0/8 | -8 | 8 Games |
| Tactical Titan v4 | 0/8 | -8 | 8 Games |
| SF-POLY 200825 | 0/8 | -8 | 8 Games |
| Claw 1.0-M | 0/8 | -8 | 8 Games |
| Alexandria 8.1.2 | 0/8 | -8 | 8 Games |
| Caissa 1.23 | 0/8 | -8 | 8 Games |
| Stockfish dev-20250824 | 0/8 | -8 | 8 Games |
| Halogen 14.17.0 | 0/8 | -8 | 8 Games |
| DarkSeid 6.5 EE | 0/8 | -8 | 8 Games |
| Viridithas 18.0.0 | 0/8 | -8 | 8 Games |
| Stockfish dev-20250824 Ivec | 0/8 | -8 | 8 Games |
| CorChess 20250824 | 0/8 | -8 | 8 Games |
| Emerald 0.4.0 | 2/2 | +2 | 2 Games |
Bread Engine 2.0.0 download mirror
Comments
Post a Comment