Which engine makes only alfa-beta search?

[Jouni]

No pruning or extensions at all. ShashChess has Full depth threads, but it's not same?

[syzygy]

No pruning or extensions at all. ShashChess has Full depth threads, but it's not same?

Some years ago I modified SF (or rather Cfish) to not do any pruning and extensions. Its nps went sky high and its Elo took a hit of 800 points.

[syzygy]

I think it is this Cripplefish branch:
https://github.com/syzygy1/Cfish/tree/cripplefish

However, it seems it still does singular and check extensions. I guess I only took out reductions and pruning. So it seems likely that the Elo loss of going to pure alpha-beta (plus qsearch) would be larger than 800.

I also did not take out aspiration search and null-window search, but those techniques do not involve pruning or extending.

[Uri Blass]

I think it is this Cripplefish branch:
https://github.com/syzygy1/Cfish/tree/cripplefish

However, it seems it still does singular and check extensions. I guess I only took out reductions and pruning. So it seems likely that the Elo loss of going to pure alpha-beta (plus qsearch) would be larger than 800.

I also did not take out aspiration search and null-window search, but those techniques do not involve pruning or extending.

I think the elo reduction is going to be smaller mainly because the evaluation today is better.

I am also not sure if singular extensions help when there are no reductions.

[syzygy]

I am also not sure if singular extensions help when there are no reductions.

They presuimably helped Deep Blue.