New engine releases & news 2021

[RubiChess]

Summer is near and my garden needs some work to do the next weeks so I released RubiChess 2.1.

https://github.com/Matthies/RubiChess/releases/tag/2.1

New stronger net and some other improvements.

Have fun.
Regards, Andreas

[Gabor Szots]

Summer is near and my garden needs some work to do the next weeks so I released RubiChess 2.1.

https://github.com/Matthies/RubiChess/releases/tag/2.1

New stronger net and some other improvements.

Have fun.
Regards, Andreas

Thanks Andreas. Our garden needs some work as well, unfortunately I can't release anything.

[Gabor Szots]

Megalodon 1.0.0: https://github.com/megalodon-chess/megalodon/releases/

[jshriver]

For those with slightly older machines, I made (hopefully) a Windows 64bit Igel 3.0.0 for "modern" aka popcnt, sse4.1 but no AVX/BMI2 instructions.

https://chess.nyc3.cdn.digitaloceanspac ... modern.zip

If there are any problems let me know, I just installed Visual Studio Community to figure out how to do this.

[voffka]

Hello jshriver,

For those with slightly older machines, I made (hopefully) a Windows 64bit Igel 3.0.0 for "modern" aka popcnt, sse4.1 but no AVX/BMI2 instructions.

https://chess.nyc3.cdn.digitaloceanspac ... modern.zip

If there are any problems let me know, I just installed Visual Studio Community to figure out how to do this.

Thanks for your efforts, but keep in mind that these are not official Igel binaries. For those people who have a custom needs for specific CPU architecture they ask me in the main Igel thread http://talkchess.com/forum3/viewtopic.p ... 79#p889179 and I compile binaries for them usually with-in the same day to let them run Igel tests. The advantage of such method is that I compile (and check) a custom build exactly targeted for a given cpu architecture, so this gives maximum performance for Igel.

For official tournaments/rating lists I encourage to use only official binaries from github page as those give the maximum performance and accurate performance rating matters a lot for rating list.

[voffka]

GreKo PSQ 1.1 - experimental version with piece/square only evaluation:
http://greko.su/greko-psq-1.1.zip

Congrats on the new GreKo release Vladimir!

[mvanthoor]

Megalodon 0.4.3 with hash tables!
https://github.com/megalodon-chess/mega ... tag/v0.4.3

But does it play legal chess already, and not crash anymore? Last time I tested it, it didn't play legally and wasn't stable.

Cosette 5.0
https://github.com/Tearth/Cosette/releases/tag/v5.0

Never heard of this engine (but there are many I never heard of, so that's not special...)

[mvanthoor]

After a lot of work and testing, Loki 3.0 is now released. Thanks to Marcel (who pointed out how underrated Loki was, its feature set taken into account), I have been working tirelessly to rework the search and evaluation function. This has paid off greatly!

I have tested the new version to have a strength of around 2510 (>600 elo points stronger than v1.2.0). This was done in three separate gauntlets against MadChess 2.2 and Raven 1.10.

The release: https://github.com/BimmerBass/Loki/releases/tag/v3.0.0

Congrats to be of help

I haven't had much time for chess programming lately. Next features for Rustic are going to be Killer, History, Aspiration Window and PVS; and a tuned and tapered evaluation after that. I still have to research the tuning. All of that stuff will require a lot of testing. After implementing the above features, I hope Rustic will have exceeded 2150 in my own testing, but it seems it always ends up 30-40 points lower on CCRL. (It could be due to opening book differences, or the fact that I test at 1m + 0.6s; maybe I should make that 2m+1s, like CCRL. But that will make the testing even longer...)

[Gabor Szots]

Megalodon 0.4.3 with hash tables!
https://github.com/megalodon-chess/mega ... tag/v0.4.3

But does it play legal chess already, and not crash anymore? Last time I tested it, it didn't play legally and wasn't stable.

I don't know but I am testing version 1.0.0 right now and it did not make an illegal move in the first 53 games.

[niel5946]

After a lot of work and testing, Loki 3.0 is now released. Thanks to Marcel (who pointed out how underrated Loki was, its feature set taken into account), I have been working tirelessly to rework the search and evaluation function. This has paid off greatly!

I have tested the new version to have a strength of around 2510 (>600 elo points stronger than v1.2.0). This was done in three separate gauntlets against MadChess 2.2 and Raven 1.10.

The release: https://github.com/BimmerBass/Loki/releases/tag/v3.0.0

Congrats to be of help

I haven't had much time for chess programming lately. Next features for Rustic are going to be Killer, History, Aspiration Window and PVS; and a tuned and tapered evaluation after that. I still have to research the tuning. All of that stuff will require a lot of testing. After implementing the above features, I hope Rustic will have exceeded 2150 in my own testing, but it seems it always ends up 30-40 points lower on CCRL. (It could be due to opening book differences, or the fact that I test at 1m + 0.6s; maybe I should make that 2m+1s, like CCRL. But that will make the testing even longer...)

Sounds like you have a lot of work ahead then! I hope it will pay off

Aspiration windows didn't work for me, even after trying numerous different window-widening strategies, but I guess it's lazy/hasty implementation is also partly responsible for the missing elo gain... If you need any inspiration for evaluation tuning, I have implemented a rather simple SPSA + Texel tuner for Loki, that you can check out