Prophet 4.3 and chess4j 5.1 released

I’m happy to finally announce the next minor release of both of my chess programs! You can grab Windows and Linux binaries from the respective Github repos:

Prophet – https://github.com/jswaff/prophet

chess4j – https://github.com/jswaff/chess4j

If you need a Mac build for Prophet, please look here. (Thank you Darius!)

The focus of this release was to continue to improve the evaluation. Prophet 4.3 and chess4j 5.1 have the exact same change log:

  • Passed pawn by rank (was a single value)
  • Non-linear mobility (was a single value)
  • Knight outposts
  • Trapped bishop penalty

These changes are worth about +50 ELO in Prophet (which I expect will bring it very close to the 2500 mark on the CCRL Blitz List). I attempted a “supported rook” term, meaning the rook on an open file is connected to another rook, but surprisingly it actually cost a few ELO. Seems that should work though, so I’ve left the code in place but have it commented out.

I had planned on doing some pawn and basic endgame work in this line, and perhaps I still will, but right now I feel the time is right to begin work on neural networks. I’m pausing development for a while to study the literature. Hopefully by spring I’m ready to begin the implementation.