martinnovaak/starzix

Starzix - C++ chess engine

Elo

CCRL Blitz: 3626 (#21/738)

CCRL Rapid: 3518 (#20/588)

Ipman Bullet: 3423 (#29/51)

Stefan Pohl SPCC: 3567 (#50/65)

How to compile

Have clang++ installed and run make

UCI (Universal Chess Interface)

Options

• Hash (int, default 32, 1 to 65536) - transposition table size in MB

• Threads (int, default 1, 1 to 256) - search threads

Extra commands

• display

• eval

• perft <depth>

• perftsplit <depth>

• bench <depth>

• makemove <move>

• undomove

Features

Board

• Bitboards
• Zobrist hashing
• Pseudolegal move generation (magic bitboards for sliders, lookup tables for pawns, knights and king)
• Copymake make/undo move

NNUE evaluation

• (768x2 -> 1024)x2 -> 1
• Lc0 data
• Trained with my trainer

Search

• Iterative deepening
• Fail-soft Negamax
• Principal variation search
• Aspiration windows
• Quiescence search
• Transposition table
• Alpha-beta pruning
• Reverse futility pruning
• Razoring
• Null move pruning
• Late move pruning
• Futility pruning
• SEE pruning
• Internal iterative reduction
• Late move reductions
• Singular extensions (with negative and double extensions)
• Check extension
• Correction history
• Cuckoo (detect upcoming repetition)
• Time management: hard and soft time limits
• Multithreading / Lazy SMP

Move ordering

• TT move
• Good noisy moves by SEE + MVV + noisy history
• Killer move
• Countermove
• Quiet moves by history
• Bad noisy moves

Moves history

• Main history
• Continuation histories (1 ply, 2 ply, 4 ply)
• Noisy history
• History malus and gravity