Riptide

Riptide is a UCI-compatible chess engine and the successor to ChessSlayer. It started as a straight port of ChessSlayer from Go to Zig, but is becoming a more performant and advanced engine over time.

Features

• Board representation: bitboard
• Move generation: pseudo-legal generation followed by legality check. 100% correct on Perft tests.
• Search: negamax with alpha-beta pruning

UCI compatibility

Riptide requires a UCI client to use as the frontend during games. It's tested against Scid vs. PC; your mileage may vary with other clients.

Currently, the following UCI features are unimplemented:

• specifying a list of moves when using the position command
• the nodes, movestogo, and mate arguments to the go command
• ponder mode

Installation

1. Install Zig version 0.10.
2. Clone the repository with git clone --recurse-submodules https://github.com/kdelwat/riptide-engine.git
3. Run cd riptide-engine && zig build
4. The riptide binary will be created in zig-cache/bin; point your GUI client to this binary.

Tests

Run unit tests with:

zig build test

Run perft correctness tests with:

zig build perft

Run node-per-second benchmarks with:

zig build nps

Profiling

zig build
valgrind --tool=callgrind zig-cache/bin/riptide
ucinewgame
position startpos
go infinite

Then run kcachegrind to analyse.

Credits

I couldn't have written this engine without the invaluable help of the Chess programming wiki and the Mediocre chess blog by Jonatan Pettersson.