Mahjong Engines
Cryolite · Riichi (Mahjong Soul rules) · Open source

Kanachan

Not an engine you can play, but a kit for building one. Kanachan trains models on Mahjong Soul game records, with the stated goal of beating NAGA and Suphx.

GitHub ↗
Built by
Cryolite, personal project 1
Rules
Riichi, Mahjong Soul standard rules 1
Approach
Imitation learning on game records 1
Strength
No trained model published 1
Access
Code on GitHub, no licence file 12

Who built it

Kanachan is a personal project by GitHub user Cryolite, started in August 2021 12. Its stated aim is an AI that can beat the top existing engines such as NAGA and Suphx 1.

Rules

Kanachan targets the rules of Mahjong Soul’s standard games, and its simulator is written to match them 1.

How it works

Tiles are fed to the model as plain tokens through embeddings, with few hand-crafted features, and the author plans to scale up to more expressive models such as transformers 1. Training starts with behavioural cloning (imitating moves in game records). It then uses what the README calls curriculum fine-tuning: the trained encoder is kept and only the decoder is swapped for a harder objective, such as score change or final placement 1.

The author reported crawling about 65 million rounds from Mahjong Soul’s Gold Room and above as of August 2021 1. The project is split into C++ tools (log annotation, a simulator, a shanten calculator and wall reconstruction) and Python training code using PyTorch 1.

Strength

No strength can be measured: the repository provides no training data and no trained models 1.

How to access it

Clone the repository and bring your own data and compute. You must collect Mahjong Soul game records yourself; the README suggests a network sniffer as one way 1. A Docker image of prerequisites and a dev container are provided for developers 1.

The repository has no licence file 2, so it grants no explicit right to reuse the code. Ask the author before building on it.

Sources

  1. Kanachan repository README (GitHub, Cryolite/kanachan)
  2. GitHub API record for Cryolite/kanachan (creation date, licence field)

Facts checked against these sources on 24 October 2026.