Gwern releases Samon Zen garden raking puzzle specification October 2026

The document specifies a 2D grid simulation where users manipulate sand via rake vectors subject to friction and particle cohesion rules. Implementation requires a solver enforcing non-overlapping strokes while preserving aesthetic asymmetry metrics drawn from traditional karesansui gardens. Source code sketches include a SAT solver backend for pattern validation.

Benchmarks in the document report 47 ms average solve time on 64x64 grids using MiniSat with custom heuristics. User tests logged 38 sessions showing median completion time of 4.2 minutes for medium difficulty patterns. These figures exceed typical casual puzzle benchmarks by 1.8x on interaction density.

The design extends Gwern's prior procedural generation work by embedding explicit HCI constraints absent from earlier text-only experiments. It addresses gaps in visual feedback latency that prior sand simulation papers overlooked. Operational deployment would require integration with WebGL for stroke rendering and export pipelines for short-form video capture.

Next steps include open-sourcing the solver harness and porting to mobile touch input within 90 days.