Meet Zahak 5.0

Jul 19, 2021 · 2 min read  ·
Share on:

When I first started working on Zahak, my goal was to get a solid understanding on chess programming and improve my chess skills. I have always wanted to make Zahak understand how to play beautiful chess. I believe I have somewhat achieved that, and currently Zahak produces one of the most eventful games. Of course, the results are not always positive, but that is a price I am willing to pay.

I also wanted to make Zahak my training companion, and I don’t think I need an engine at Stockfish level for this matter, I will be perfectly happy if my trainer is as strong as the world champion. I believe any engine with the rating of 2700 (according to CCRL Blitz) or higher is sufficient for training purposes, so I made this rating my secondary goal.

I am happy to announce that Zahak 5.0, will most likely cross this barrier and should be just north 2700, which also means my quest for improving the strength of Zahak is near the end. But of course, that doesn’t mean I will be stopping working on it, it is just that I will not be seeking strength for the sake of making it stronger any more.

My future versions will probably be of the kind of making Zahak more entertaining, and adding more evaluation terms that might not add strength, but might add pleasure for us humans.

Things that I believe I will be working on next include:

  • Adding Multi-PV
  • Adding Lazy SMP
  • Porting Fathom to Go Lang, and adding Syzygy to Zahak
  • Adding an NN eval (maybe NNUE or something else), and training it with chess games from the romantic era, which probably makes the engine weaker but more human like
  • Probably more

Zahak 5.0, comes with the following added features/fixes:

  • SEE pruning in normal search
  • LMR and pruning tweaks
  • Re-doing move history heuristic
  • Adding evaluation terms for Bishop pair
  • Adding evaluation terms for Knight outposts
  • New and improved time management
  • Re-implemented mobility/aggressivity, so that different types of pieces are treated differently
  • Pawnhash
  • Fixing various bugs in search

To download Zahak 5.0, please visit here