Lambergar

[EzioMagnifico]

Lambergar v0.3
Thanks to the Author jabolcni

UCI chess engine written in zig .



Download : https://github.com/jabolcni/Lambergar/releases/tag/v0.3

This is the first public release of Lambergar chess engine.

[EzioMagnifico]

Lambergar v0.3.1
Thanks to the Author jabolcni

UCI chess engine written in zig .

Download : https://github.com/jabolcni/Lambergar/releases/tag/v0.3.1

This is the first public release of Lambergar chess engine .

[EzioMagnifico]

Lambergar v0.3.1b
Thanks to the Author jabolcni

UCI chess engine written in zig .

Download : https://github.com/jabolcni/Lambergar/releases/tag/v0.3.1b

Fixed issues with UCI commands requiring space after command to work on Windows.
Compiled for two Intel architectures

[EzioMagnifico]

Lambergar v0.3.1c
Thanks to the Author jabolcni

UCI chess engine written in zig .

Download : https://github.com/jabolcni/Lambergar/releases/tag/v0.3.1c

release with different x86-64 microarchitecture levels

x86-64 is baseline microarchitecture

x86-64-v2 supports vector instructions up to Streaming SIMD Extensions 4.2 (SSE4.2) and Supplemental Streaming SIMD Extensions 3 (SSSE3), the POPCNT instruction.

x86-64-v3 adds vector instructions up to AVX2, MOVBE, and additional bit-manipulation instructions.

x86-64-v4 includes vector instructions from some of the AVX-512 variants.

(source: https://developers.redhat.com/blog/2021/01/05/building-red-hat-enterprise-linux-9-for-the-x86-64-v2-microarchitecture-level#background_of_the_x86_64_microarchitecture_levels)

[EzioMagnifico]

Lambergar v0.4.0
Thanks to the Author jabolcni

UCI chess engine written in zig .

Download : https://github.com/jabolcni/Lambergar/releases/tag/v0.4.0

Main features :

New evaluation parameters :
Tuner for evaluation parameters
Changed history heuristics and move sorting
Improved apiration window algorithm
Changes in prunings and reductions
I have been changing and massaging the code quite a bit, so I lost the track of all the changes, but the improvements are quite substantial
Time controls 30s+0.5s

Score of Lambergar vs Lamb031: 133 - 11 - 52 [0.811] 196
... Lambergar playing White: 68 - 3 - 26 [0.835] 97
... Lambergar playing Black: 65 - 8 - 26 [0.788] 99
... White vs Black: 76 - 68 - 52 [0.520] 196
Elo difference: 253.3 +/- 47.4, LOS: 100.0 %, DrawRatio: 26.5 %

[EzioMagnifico]

Lambergar v0.4.1
Thanks to the Author jabolcni

UCI chess engine written in zig .

Download : https://github.com/jabolcni/Lambergar/releases/tag/v0.4.1

Release Notes .
This release includes two bug fixes:

Excessive Memory Usage: We resolved an issue with excessive memory usage. The problem originated from the use of an incorrect memory allocator. Previously, we used the Arena memory allocator, which, according to a discussion on Ziggit, does not release memory. We have now switched to using the c_allocator directly.

Engine Unresponsiveness: We fixed an issue where the engine would get stuck in search mode and not respond to commands from the interface. This was due to the use of a single thread, and interfacing was only possible once the search had finished. We have now resolved this by using a separate thread for the search routine. This improvement also lays the groundwork for implementing a multi-threaded search in the future.

Please note that these changes do not improve the engine's strength.

[EzioMagnifico]

Lambergar v0.5.0
Thanks to the Author jabolcni

UCI chess engine written in zig .

Download : https://github.com/jabolcni/Lambergar/releases/tag/v0.5.0

Builds
Currently there are two basic builds: vintage and popcnt. The vintage version is for really old computers, while popcnt is for modern computers.

Main Features
Improved evaluation function: Now includes tuned:
Piece values
PSQT (Positional Square Table)
Pawn evaluation:
Passers
Isolated pawns
Blocked pawns
Supported pawns
Evaluation of pawn phalanx
Piece mobility
Piece attacking evaluation
Basic king safety
Some minor improvements: Search function, history heuristics, and move sorting
Time controls: improved time controls

[EzioMagnifico]

Lambergar v0.5.1
Thanks to the Author jabolcni

UCI chess engine written in zig .

Download : https://github.com/jabolcni/Lambergar/releases/tag/v0.5.1

Release Notes :
This release brings several bug fixes, with the major one addressing a flaw in the calculation formula for determining the new history value. The previous formula did not limit the history value, leading to an integer overflow issue at certain points, resulting in negative values. Consequently, during move sorting, the best quiet moves were erroneously placed last. This issue was more pronounced during longer time controls, where there were more opportunities to increase the history value. At lower time controls (up to 10 seconds per move), the new formula may actually reduce the engine's strength by 10-20 ELO points. However, at longer time controls, version v0.5.1 demonstrates improvement in engine strength over the previous version. At approximately 1 minute per move, the new version is approximately 50 ELO points stronger, with even more significant gains observed at longer time controls.

[EzioMagnifico]

Lambergar v0.5.2
Thanks to the Author jabolcni

UCI chess engine written in zig .

Download : https://github.com/jabolcni/Lambergar/releases/tag/v0.5.2

Release Notes :
- This release brings some minor bug fixes.
- UCI interface has been reorganized and is now smaller in terms of code size, but has same functionality.
- Some code refactoring so that the project can be compiled with newer zig versions. However, zig versions newer than 0.12.0-dev.1536+6b9f7e26c make engine really slow.
- Strength of the engine remains the same as in version v0.5.1.