Stockfish README

The project's README from github.com/official-stockfish/Stockfish. As one markdown file: README.md.

Stockfish

Stockfish

A free and strong UCI chess engine.
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Overview

Stockfish is a free and strong UCI chess engine derived from Glaurung 2.1 that analyzes chess positions and computes the optimal moves.

Stockfish does not include a graphical user interface (GUI) that is required to display a chessboard and to make it easy to input moves. These GUIs are developed independently from Stockfish and are available online. Read the documentation for your GUI of choice for information about how to use Stockfish with it.

See also the Stockfish documentation for further usage help.

Files

This distribution of Stockfish consists of the following files:

Contributing

See Contributing Guide.

Donating hardware

Improving Stockfish requires a massive amount of testing. You can donate your hardware resources by installing the Fishtest Worker and viewing the current tests on Fishtest.

Improving the code

In the chessprogramming wiki, many techniques used in Stockfish are explained with a lot of background information. The section on Stockfish describes many features and techniques used by Stockfish. However, it is generic rather than focused on Stockfish's precise implementation.

The engine testing is done on Fishtest. If you want to help improve Stockfish, please read this guideline first, where the basics of Stockfish development are explained.

Discussions about Stockfish take place these days mainly in the Stockfish Discord server. This is also the best place to ask questions about the codebase and how to improve it.

Compiling Stockfish

Stockfish has support for 32 or 64-bit CPUs, certain hardware instructions, big-endian machines such as Power PC, and other platforms.

On Unix-like systems, it should be easy to compile Stockfish directly from the source code with the included Makefile in the folder src. In general, it is recommended to run make help to see a list of make targets with corresponding descriptions. An example suitable for most Intel and AMD chips:

cd src
make -j profile-build

Detailed compilation instructions for all platforms can be found in our documentation. Our wiki also has information about the UCI commands supported by Stockfish.

Terms of use

Stockfish is free and distributed under the GNU General Public License version 3 (GPL v3). Essentially, this means you are free to do almost exactly what you want with the program, including distributing it among your friends, making it available for download from your website, selling it (either by itself or as part of some bigger software package), or using it as the starting point for a software project of your own.

The only real limitation is that whenever you distribute Stockfish in some way, you MUST always include the license and the full source code (or a pointer to where the source code can be found) to generate the exact binary you are distributing. If you make any changes to the source code, these changes must also be made available under GPL v3.

Acknowledgements

Stockfish uses neural networks trained on data provided by the Leela Chess Zero project, which is made available under the Open Database License (ODbL).

Stockfish (official-stockfish/Stockfish)

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Stockfish
What is this?Stockfish is a free, strong UCI chess engine derived from Glaurung 2.1 that analyzes chess positions and computes the optimal moves.
So is this a chess program with a board I can play on?No — it is only the engine, with no GUI. You pair it with an independently developed chess GUI that displays the board and lets you input moves; Stockfish does the analysis underneath.
How do I get it running?Compile it from source: on Unix-like systems use the included Makefile in the src folder, starting with 'make help' to list targets (an example target suits most Intel and AMD chips). Detailed instructions for all platforms are in the wiki.
What kind of hardware can it run on?It runs on 32 or 64-bit CPUs, takes advantage of certain hardware instructions when available, and even supports big-endian machines such as Power PC, among other platforms.
Can I use it in my own app, or even sell it?Yes — GPL v3 lets you redistribute it, sell it, or build a project on it. The catch: any distribution must include the license and full source, and your changes must also be released under GPL v3.
Does Stockfish use a neural network?Yes — it evaluates positions with NNUE. The distribution includes a file with the .nnue extension that stores the neural network, and binary distributions have this file embedded.
Where does the training data for its neural network come from?From data provided by the Leela Chess Zero project, which is made available under the Open Database License (ODbL).
How can I help make Stockfish stronger?Improving it requires a massive amount of testing: you can install the Fishtest Worker and donate hardware to the testing framework, or follow the development guideline to improve the code. Discussion happens mainly on the Stockfish Discord.
What are similar projects?dlib, ninja, tensorflow, AirSim, CNTK, DeepSpeech, caffe, openage
Which topics is it in?engine, unix, algorithms, neural-network, artificial-intelligence, cpp, c++, gplv3, machine-learning, free, tool, ai
Creator
official-stockfish
Size
20.1 MB
Stars
16.9K
Updated
CommitOct 13Releasesf_19Sep 05
Age
12y
Commits · 90 Days