logo (C) Bas Schuiling


STOP is my GO (Weiqi, Baduk) playing program.
It is a go-brain; a program that decides by itself what counter-moves to do for each move the user types in.

What is Go?

Wikipedia defines Go as: "Go is a strategic board game for two players. It is also known as igo (Japanese), weiqi or wei ch'i (Chinese) or baduk (Korean). Go is noted for being rich in strategic complexity despite its simple rules.".

Files - source code
stop-1.0b-001.jar - latest binary

stop-0.7-012.jar - more algorithm adjustments
stop-0.6.jar - algorithm adjustments
stop-0.5.jar - Go-fixes (now really no more suicides or KO-moves), GTP fixes, alorithm improvements
stop-0.4.jar - fixed suicide-moves and KO-moves
stop-0.3.jar - implemented the GTP-protocol, added commandline switches
stop-0.2.jar - better freedoms detection
stop-0.1.jar - initial version

Using To set the board-size, add '--boardsize x' where x is any value larger than 1.


java -jar stop.jar --mode console
From a GTP GUI:
java -jar stop.jar --mode gtp


Program -> New Program
Then, for command enter the path to the java-binary with behind it: -jar stop.jar --mode gtp
/usr/bin/java -ea -jar /path/to/stop.jar --mode gtp

What does it look like

In your browser!

You can play against Stop in your current browser by following this link.

Screendump of console-mode

Games played


This is the 4th game played by Stop against GnuGO.


Stop plays with several versions at the CGOS server. Its rating can be seen here:

Tested with

Verified to run with:

For contact info, see this page.

mastodon icon toot this