bubikopf

UCI-compliant chess engine.

(The yellow sticker is for catching bugs.)

specs

• written in C++20
• no dependencies to external libraries
• move generation visits about 25k nodes/ms on an Intel i7-6700HQ
• iteratively deepening negamax search with alpha / beta pruning
• principal variation is tracked via triangular table
• rating not determined yet

missing features

• NNUE based static evaluation
• draw due to threefold repitition (via hash table)
• draw due to 50 move rule
• draw due to insufficient material

linux build instructions

• install the bazel build system
• clone this repository to your machine
• build the engine binary:

cd <clone_dir>
bazel build //play:bubikopf
cp <clone_dir>/bazel-bin/play/bubikopf <path_where_you_want_the_binary>

(Tested on Ubuntu 20.04 with x86_64 CPU.)

acknowledgements

For the development of bubikopf the following open source projects were used. A big thanks to the authors and contributors:

• Mk-Chan/BBPerft (reference implementation for debugging and benchmarking)
• ShailChoksi/lichess-bot (bridge between engine binary and lichess server)

And of course lichess. Hands down the best chess plattform out there. Go check it out.