Mantissa

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Mantissa, an UCI compatible open source chess engine by Jeremy Wright, written in Rust, licensed under the GPL v3.0, first released in September 2021. Supported by Zahak author Amanj Sherwany, Mantissa v3.0.0, released in December 2021, came with an NNUE implementation of a 769 -> 128 -> 1 net topology. In Mantissa v3.3.0, released in January 2022, the net topology was changed due to an inspiration from reading Koivisto's source code, considering board symmetry. Now instead of a 769th feature for side to move, the new net uses 2 sets of 128 neurons in the hidden layer with mirrored weights to reflect the game from the point of views of both sides.

=Selected Features=

Board Representation

 * Bitboards
 * Magic Bitboards

Search

 * Iterative Deepening
 * Aspiration Windows
 * Lazy SMP
 * Principal Variation Search
 * Transposition Table
 * Selectivity
 * Null Move Pruning
 * Late Move Reductions
 * Late Move Pruning
 * Futility Pruning
 * Reverse Futility Pruning
 * Singular Extensions
 * Multi-Cut
 * Quiescence Search
 * SEE Pruning
 * Move Ordering
 * MVV-LVA
 * Killer Heuristic
 * History Heuristic
 * Countermove Heuristic

Evaluation

 * NNUE (v3.0.0)
 * Tapered Evaluation
 * Material
 * Bishop Pair
 * Piece-Square Tables
 * Mobility
 * Rook on Seventh
 * Rook on (Semi) Open File
 * Pawn Structure
 * Pawn Hash Table
 * Doubled Pawn
 * Isolated Pawn
 * Backward Pawn
 * Advanced Connected Pawns
 * Passed Pawns
 * King Safety

=Forum Posts=
 * New Engine: Mantissa by Jeremy Wright, CCRL Discussion Board, September 19, 2021
 * Mantissa 3.0.0 by Jeremy Wright, CCC, December 10, 2021

=External Links=

Chess Engine

 * GitHub - jtheardw/mantissa: Chess Engine
 * Mantissa az CCRL 40/15

Misc

 * Mantissa from Wikipedia
 * Common logarithm from Wikipedia
 * Significand from Wikipedia
 * Mantissa - Land of The Living (1992),YouTube Video

=References= Up one level