Puffin is a UCI-compatible chess engine written in C#.
Download the latest version here. Only use the legacy executable if your CPU does not support PEXT instructions.
If you want to compile it yourself, the only prerequisite is the .NET 8 SDK.
Puffin is a command-line application and does not provide any user interface. Popular free GUI programs are:
Follow the instructions for the GUI on how to add a new engine.
Or you can play against it on lichess.
A non-exhaustive list...
Search:
- NegaScout
- Iterative deepening
- Aspiration window
- Quiescence
- Staged move generation
- PEXT sliding piece move generation
- Legacy uses Kindergarten Super SISSY Bitboards (KiSS)
- Late move reductions
- Null move pruning
- Futility pruning
- Reverse futility pruning
- Transposition table (always replace scheme)
Evaluation:
- Piece square tables
- Mobility
Evaluation values have been tuned using the lichess-big3-resolved dataset.
- Chess Programming Wiki
- The Engine Programming Discord channel and its many users
- The talkchess forums
- The texel tuner made by Gedas
- Other open-source chess engines. Some that I have looked at and used for testing: