Apologies for dredging up this old topic, but software keeps improving, and I hope to find an active link to a (preferably free) bot that can crush my skull whenever I want. I already have a hex gui java app with a menu option to attach an engine. My OS is Linux Mint. The bot should handle the pie rule and different grid sizes, or maybe different bots optimized for different sizes. Time management (for example, N seconds main time per game and M seconds increment or delay per move) would be nice but not necessary.

Thanks for your help!

If you get nix on your system you can use what I believe is the current best AI using this flake (a nix thing).

Oh no, it's that easy now…

I installed it and I'm already depressed. I know nothing about hex.

Yes, “KataHex” as we've been calling it is very strong. It's also a great tool for analyzing your games!

I believe the original author was from this post here (or at least this is who I emailed to get a copy of the bot from, after finding references to it on HexWiki).

As a matter of fact I'm considering to take back what I said. KataHex seems to sometimes be very certain about things, but then completely change it's mind.
I'll give it some time. Surely it's a great tool and a super strong engine, but maybe it's as flawed as human players.

Is there a way to change the board UI to show the actual hexagons?

Some links from HexWiki:

1. KataHex's swap map for 15x15 and 19x19.

2. My attempt at a 19x19 opening strategy guide based on KataHex

An interesting question is what handicap KataHex can give and still beat top human players on 19x19. My bold prediction is that KataHex is favored to win even with a 0.5 stone handicap (KataHex plays white with no swap rule).

Is there a way to change the board UI to show the actual hexagons?

No, keep in mind this basically a barely-modified Go engine (katago). It even has a prediction for the score differential.

I still have found no time to install KataHex, i'm following chess engines and i had planned to take a look at go engines soon…

regarding hexanna's work, i think that she has contributed quite a lot to hex now!

i disagree with some choice of terminology of her guide but i agree with all or almost all of the substance

I have finally installed kata to analyze my last game with Arek. As expected it's filled with errors. Somewhat surprisingly, it's white f6 that seem to turn a white win into a white loss. Anyway, does anyone know how to install kata with the CUDA backend with the nix tool?

More precisely, it's filled with questionable moves and unfortunately there are only also a few real errors. :(

Yesterday I ran one single game and during game Kata changed his mind in one move from 40% in black's favour to ~85%, although I played his suggestions. It was quite surprising for me.

But anyway quite strong move suggestions, even analyzing one his game I learned some nice patterns or I have just gained confidence about some moves.

Today I have finished installation, I tried both cudaDNN (requires patching CMakeList.txt) and TensorRT, I recommend the latter if anyone is interested, it's also easier to install. For installation you can use git from GitHub.

Sorry, I need a bit of hand-holding here. I already have hexgui 0.9.0 by Broderick Arneson from 2010, which provides the hexagon style board Arek is interested in, as well as my preference, equilateral triangles. In the Program menu is the “Connect local program…” option and I hope to be able to access the KataHex engines (optimized for different sizes) that way. How can I get there? Thank you.

David, I don't know if Kata supports that guy, but you can try:

You can get the engine on linux by doing:

git clone -b Hex2022 https://github.com/hzyhhzy/KataGo.git

then you go into the directory and do the following commands:

cd KataGo/cpp/
mkdir build
cd build
cmake ..

(if you have an NVIDIA card you should use cmake -DUSE_BACKEND=TENSORRT ..)

then make -j 8

and then you should have the binary ready for running.

Maybe something similar to above procedure also works on linux but I don't know.

With Nix you also get the Kata GUI, I haven't yet looked into the details of how to download and run it form git directly.

hexgui can't work with KataHex. We use a fork of LizzieYzy, you can download the prebuilt one here