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Anodos 1.3.0 - new version chess engine

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Anodos - UCI chess engine github:https://github.com/tomcant/anodos/releases Author: Tom Cant (London, United Kingdom) Anodos 1.3.0 what's new? Additions Static exchange evaluation (SEE): evaluate capture sequences to order good captures before bad ones in move ordering. Delta pruning: prune nodes in quiescence search where the material gain cannot possibly raise alpha. Skip bad captures in quiescence: use SEE to avoid searching losing captures in quiescence. Late move pruning: skip late moves entirely at low depths where they are unlikely to improve the position. Internal iterative reduction: reduce depth when no TT move is available since these positions are less likely to be interesting. Insufficient material detection: detect draws when neither side has enough material to deliver checkmate (this is not strict FIDE draw rules, positions like KNN vs K are treated as draws since they require "helpmate", which the engine discards the possibility of). Enhancements More agg...

Anodos 1.2.0 - new version chess engine

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Anodos - UCI chess engine github:https://github.com/tomcant/anodos/releases Author: Tom Cant (London, United Kingdom) Anodos 1.2.0 what's new? This release brings the largest strength increase the engine has seen so far, driven mostly by the introduction of HCE terms. Additions Handcrafted evaluation: King safety with pawn-shield scoring. Doubled, isolated, and passed pawns. Open and half-open files for rooks. General piece mobility scoring. Late move reductions to speed up search in unpromising branches. Enhancements Think for longer in complex positions. Reuse the transposition table across moves. Stop searching beyond mate when working with a time limit. Play forced moves immediately instead of spending time searching. SPRT result vs 1.1.0 Results of 1.2.0 vs 1.1.0 (10+0.1, NULL, 64MB, 8moves_v3.pgn): Elo: 432.56 +/- 65.28, nElo: 629.13 +/- 38.07 LOS: 100.00 %, DrawRatio: 7.50 %, PairsRatio: 73.00 Games: 320, Wins: 284, Losses: 13, Draws: 23, Points: 295.5 (92.34 %) Ptnml(0-2):...

Anodos 1.1.0 - new version chess engine

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  Anodos - UCI chess engine Author: Tom Cant (London, United Kingdom) Anodos 1.1.0 what's new? Additions History heuristic to improve quiet move ordering during search. Reverse futility pruning to reduce unproductive search in clearly bad positions. Benchmarking with the bench command (added a bench subcommand for collecting PGO profiles). Enhancements Initialise transposition table once and reuse it via an age property, avoiding TT reinitialisation between searches. Incremental move picking instead of sorting moves at every node, reducing per-node overhead. King PSQT tapered by game phase to hopefully reduce losses by poor awareness of king safety in the endgame. Other PGO for release builds (release pipeline now builds engine binaries using profile-guided optimisation). Windows builds for each release (release artifacts now include a Windows build alongside existing targets). SPRT result vs 1.0.0 Results of 1.1.0 vs 1.0.0 (10+0.1, NULL, 64MB, 8moves_v3.pgn): Elo: 122.97 +/- ...