Yukari is a primarily xboard-protocol chess program. (UCI support exists, but xboard should be preferred if your GUI isn't from the stone age.)

yukari is currently being rewritten. future development will occur in that repository, which may be moved to this location.

Yukari uses nightly Rust features to accelerate NNUE evaluation without the author's eyes bleeding, and cargo-pgo to automate a profile-guided optimisation run.

rustup component add llvm-tools
cargo install cargo-pgo
make

• 2025.4.1: approximately 3450 CCRL 40/4
• 2025.3.4: 3376 CCRL 40/4; 3329 CCRL 40/40
• 2025.2.4: 3081 CCRL 40/4; 3103 CCRL 40/40
• 2024.12.1: 2825 CCRL 40/4; 2824 CCRL 40/40

in no particular order:

• @Lunaphied who wrote the xboard protocol code
• @87flowers for motivating me to pick up Yukari after three years and for running lots of Yukari datagen
• @analog-hors for patiently debugging my transposition table code
• @dannyhammer for hosting and sharing the Toad OpenBench instance
• @Ciekce for guiding the NNUE implementation
• @JonathanHallstrom for running Yukari datagen
• Jim Ablett, for building binaries
• the Loftycord, for being amazing friends

sometimes you can teach an old wolf new tricks.