top of page

Booot 7.1 - released.

Another great surprise for computer chess aficionados!

The recognizable and well-liked Booot chess engine has seen the light of day in version 7.1.

Booot is a free chess engine with shared source code by Alex Morozov. It is the most powerful chess engine written in Pascal language !

Here are what changes have been made in Booot 7.1.


1. Finally i revisited all IO and SMP code and excluded all Windows dependencies. From this time it is possible to build Booot under any OS with FreePascal (Lazarus) compiler. I build binaries also for Linux and Macos (Darwin64).

2. Completely rewritten all Asm SIMD procedures. There are 3 binaries under all platforms : for Avx2, for avx+pext(bmi2) and for avx512

3. Releases now are in GitHub with sources.

4. Finally i found and fixed the oldest BUG, causing hangings and crashes in SMP (especially with big number of threads, like TCEC). It was ugly.

5. Fixed bug "wrong PV" under cutechess-cli

6. Fixed bug cousing problems with cutechess-cli in "concurensy>1" mode. Now it works fine.

7. New , bigger, NN. From this time - NN will be inside the binary.

8. Booot is quicker, smarter, and, i hope, stronger.


Source: TalkChess

It is noteworthy that the latest Booot has been prepared not only for Windows users, but also for those who use Linux and Mac (x64 versions).

The only thing missing for full happiness is a version for Linux and Mac running on ARM CPU's, such as Apple Silicon.

I don't want to jinx it, but... (soon I hope) there is a chance for a Booot binary for these devices.

Here are two examples of what the latest Booot 7.1 is capable of.

Booot 7.1 (white) vs Viridithas 7.0.0 (black).

Viridithas is a strong opponent, playing very impressively and dangerous at every stage of the game.

Although Booot has a material advantage, it must play as accurately as possible to achieve victory in the following position.

Booot 7.1 does this in an extremely impressive way: 54. Rxg7+!!

Download ZIP • 4KB

Stockfish 15.1 (white) vs Booot 7.1 (black).

Is there a force capable of stopping one of the strongest chess engines in this world? And still in a game in which it disposes of white and attacks the exposed position of the black King?


Booot 7.1 can do this, and it did so playing against Stockfish 15.1.


Download ZIP • 3KB

For fans of Booot chess engine and its author, perhaps something special will be coming for you soon - look out carefully on the :)

Source: Giphy

Booot 7.1 is ready for download from its page on GitHub.


In the Files area you will find free chess engines for download.


* Diagrams created with ChessBase 17


bottom of page