Sisyphus32 ♟

Sisyphus32 is an open-source pruning-based chess engine! It can be run as an executable, where it uses UCI for communication. Alternatively, it can be used as a crate.

Lichess Bot

Supported UCI Commands (documentation)

Sisyphus32 is UCI-compliant, implementing the following UCI commands:

• uci
• ucinewgame
• isready
• position (fen <fenstring> | startpos) [moves <move1> ... <movei>]
• go [perft <plies> | [depth <plies>] [wtime <ms>] [btime <ms>] [winc <ms>] [binc <ms>] [movetime <ms>]]
• stop | s
• quit | q
• exit | e
• eval
• display | d
• bench | benchmedium
• benchlong
• benchshort
• setoption name Clear Hash
• setoption name Threads value <n>
• setoption name SyzygyPath value <path>
• setoption name LichessToken value <token>
• setoption name Hash value <size_mb>

Local Development

Setup

1. Install Rust.
2. (OPTIONAL) Download a syzygy tablebase and put it in tables/syzygy/ for optimal endgame performance.
3. (OPTIONAL) Create a personal access token at https://lichess.org/account/oauth/token/create (no scopes need to be selected), copy and rename .env.example to .env, then fill in the value to enable the opening book.

How to use

1. Run cargo build --release to build the strongest version of the engine.
2. Run cargo run --release to build and run the strongest version of the engine.
3. Run cargo run --release --no-default-features --features <version> to build and run a specific version of the engine. Version names can be found in src/versions.rs.
4. Run cargo test -- --test-threads=1 to run all unit and integration tests.
5. Run cargo run --bin test_all to run all unit and integration tests for all versions.
6. (WINDOWS ONLY) Run cargo run --bin build_all to build executables for all versions to target/release_all/.
7. (WINDOWS ONLY) Run cargo run --bin cutechess_sprt <version1> <version2> to run SPRT against the specified versions, which should correspond to binary names in target/release_all/. This requires Cute Chess to be installed.
8. (WINDOWS ONLY) Run cargo run --bin samply_profile <profile name> to run a profiler on the specified profile name, which should correspond to a file in src/bin/. This requires Samply to be installed.