cm-engine-runner

A JavaScript module to act as a framework for running chess engines in the browser.

Working engines

Stockfish 18

• npm package: stockfish (v18.0.5)
• File: node_modules/stockfish/bin/stockfish-18-lite-single.js
• Type: WASM (single-threaded lite variant)
• https://github.com/nmrugg/stockfish.js

Polyglot opening books

• An engine to play moves from a polyglot (.bin) openings file.
• https://github.com/shaack/cm-polyglot

Stockfish Skill Levels

this.uciCmd('setoption name Skill Level value ' + (LEVELS[props.level][1]))

• Level 0 = 1100 ELO rating
• Level 1 = 1165 ELO rating
• Level 2 = 1230 ELO rating

As you can see the strength is increasing by 65 ELO points for each level, so that;

• Level 20 = 2570 ELO rating.

And depth to ELO: https://chess.stackexchange.com/questions/8123/stockfish-elo-vs-search-depth?rq=1

References

• UCI reference
• Official Stockfish
• stockfish.js
  • https://github.com/mcostalba/Stockfish
  • https://github.com/niklasf/stockfish.js (stockfish-v10-niklasf.js)
  • https://github.com/bjedrzejewski/stockfish-js <= supports opening books
• chess-tools
• https://www.chessprogramming.org/Opening_Book#Formats
• https://github.com/evilwan/stakelbase

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