Home | Jackdaw

RL Project Guide — Observations, actions, masks, rewards, the Gymnasium wrapper (works with MaskablePPO) and the vector env

Evaluating on Jackdaw Arena — The hosted benchmark: server-held seeds, a fixed budget per agent, verified and public results

Python API — The Rust-backed Game: actions, legal moves, views, previews, snapshots, GameBuilder, speed

Lockstep against the live game — jackdaw lockstep, divergence bundles, replay, the deviation catalog, and where the live game isn’t vanilla

Validation & Scenarios — Validating the engine against live Balatro, writing your own test scenarios

BalatroBot on the simulator — jackdaw serve, SimBackend, and how the simulator maps onto BalatroBot’s API

Snapshot schema — jackdaw.snapshot/1, the save and comparison format

Development — The toolchain, the everyday commands, game data and fixtures

Jackdaw