Caylus AI

This is a project to write computer opponents for the board game Caylus. Currently this is very much a work-in-progress.

This program implements a game copyrighted and manufactured by Ystari Games. They have given me permission for me to create a computerized version of the game.


2012-06-11 - Version 0.114, there are now six named bot personalities to play against (so far, they are still pretty weak, but I will work on making them stronger); also, you can now choose what color you want to play as (see Game, Options); there are also a few minor bug fixes.

2012-05-03 - Version 0.113, with this version you can play with your own custom graphics. Just place a file named 'gameboard.bmp' and/or 'all_buildings.bmp' in the Caylus directory. See Caylus Graphics for more information.

2012-04-30 - Version 0.112, new building selection dialog box for Carpent, Mason, Architect; also, now you can select "Buildings Supply" from the "View" menu to see all available buildings. Also, this release has another fix for the building-replaced-by-a-residence bug that was introduced in 0.109 and was not really fixed in 0.111. Enjoy!

2011-12-21 - Version 0.111, fixes a bug introduced in 0.109 that did not allow rebuilding of a building replaced by a residence

2011-10-23 - Version 0.110, fixes a bug introduced in 0.109 that prevented being able to build from the favor track

2011-10-13 - I have published an initial version of a "bot writer's guide", for anyone who wants to try to make their own AI personality for Caylus. See the new "Hacking" section below for a link.

2011-10-13 - Version 0.109, the default AI now takes the Inn sometimes; found and fixed a bug in building a residence from the favor (the discount was not given); made an incompatible change to how build moves are encoded, this affects the safe-file format, and it may cause some AI personalities to break in some way that I could not test

2011-09-11 - Version 0.108, implemented Edit->Undo/Redo, use embedded dialog boxes for move selection, hide game tree view by default

2011-08-20 - Version 0.107, fixed bug involving Game->Save, made choice of payment for carpenter a drop-down menu

2011-08-15 - Version 0.106, building names in popups, images in the build dialog, color nodes in game tree view

2011-07-11 - Version 0.105, recreated board image again, this time using vector graphics, for much better visuals

2011-03-20 - Version 0.104, recreated board image for crisper images; also used new graphics in player mats and buttons

2011-02-21 - Version 0.103, recreated building graphics for crisper images

2011-02-11 - Version 0.102, fixed a crash bug; reduced flickering; display cost when moving provost

2011-01-17 - Version 0.101, fixed a few obvious things from the first release

2011-01-16 - Version 0.100, initial public release


This program will only work on Windows. Download the ZIP file and extract it anywhere on your hard disk. Run the caylus.exe file.



It is assumed you already know how to play the board game. In a future version, the program may give you more hints about how to play. Also, the program uses f or "food" to refer to the pink resources, w or "wood" to refer to the brown resources, etc.

Most of the game is choosing where to place your next worker. This is done simply by clicking on the board.

When buildings are activated, you will be prompted to pick up resources, or build a building, etc. These prompts appear in the right-hand section.


If you'd like to help make this program better, please contact me. (See below for contact information.)

Computer Players

The motivation of this project was to develop a good computer player for the game. The computer player logic is written in the Lua scripting language. If you would like to work on developing the AI, please take a look at the Caylus Bot Writer's Guide. This guide, like the Caylus program itself, is a work-in-progress.


As of version 0.113, the graphics are a mix of vectorized images of the original game components and scans of some of the original images. I would prefer to have all original artwork for the program. If anyone out there would enjoy making new graphics for this game, please start by downloading the Caylus Graphics file.

Contact Information

Questions and comments may be sent to