Chess engines: Heimdall 1.2.2

Heimdall - UCI chess engine written in Nim.

Author: Mattia Giambirtone

More info
Heimdall is available on Lichess under its old name (Nimfish), feel free to challenge it! I try to keep the engine running on there always up to date with the changes on the master branch

v.1.2.2:

This release addresses a bug that I had inadvertently introduced while refactoring Heimdall's SMP functionality. For simplicity (and my own sanity), I have reverted the change and switched back to the old way of spawning threads, which means they are re-created at every go command (inefficient, but at least it works!)

Please refer to 1.2's release notes for an accurate changelog and strength improvements

SMP Scaling

Here follows the results of a 2v1 threads test I ran to verify that I had indeed fixed my multithreading support:

Elo   | 55.14 +- 10.85 (95%)

SPRT  | 8.0+0.08s Threads=2 Hash=16MB

LLR   | 2.89 (-2.25, 2.89) [0.00, 3.00]

Games | N: 1328 W: 419 L: 210 D: 699

Penta | [4, 94, 288, 245, 33]

https://chess.n9x.co/test/475/

Heimdall 1.1.1 vs other engines:

Rhetoric 1.4.3	15.5/16	+15	16 Games
Tcheran 4.0	6/6	+6	6 Games
Eubos 3.7 JA	5/6	+4	6 Games
Stockfish 17	0/6	-6	6 Games
Catto 0.12.5	5/5	+5	5 Games
Kairuku 1.0.1 JA	5/5	+5	5 Games
Perseus 0.9-alpha	5/5	+5	5 Games
Koedem 1.1.2 JA	5/5	+5	5 Games
Freda 1.0	4/4	+4	4 Games
TomitankChess 5.1 JA	4/4	+4	4 Games
CT800 1.46	4/4	+4	4 Games
Schoenemann 0.3.0	4/4	+4	4 Games
CalvinChess 4.3.0 JA	1.5/4	-1	4 Games
Alexandria 7.1.0	0.5/4	-3	4 Games
Yuliana 5.50	0.5/4	-3	4 Games
Obsidian 14.0	0.5/4	-3	4 Games
JigSaw 6.0	0.5/4	-3	4 Games
Rebel-EAS 2.0	0.5/4	-3	4 Games
Stormphrax 6.0.0	0/4	-4	4 Games
Big Yuli GM 221024	0/4	-4	4 Games
Quanticade Electra 0.9	0/4	-4	4 Games

Heimdall 1.2.2 download

Github: https://github.com/nocturn9x/heimdall