# Third-party software and data | Component | Licence | Use here | |-----------|---------|----------| | ChessQueries code and weights, including ChessQ Lite (github.com/JSeytre/chessqueries, Hugging Face `joelseytre/chessqueries`, `joelseytre/chessq-lite`) | PolyForm Noncommercial License 1.0.0 (full text below) | Recognition model. Weights are downloaded at build/eval time and are never committed (`*.onnx` and `web/public/models/` are git-ignored). **Non-commercial use only.** | | DINOv2 encoders inside the ChessQueries weights | Apache-2.0 (`third_party/*/LICENSE-DINOv2`) | Part of the weights; attribution travels with them. | | chessground (npm `chessground`) | GPL-3.0 | Board UI. This is why the app source is GPL-3.0. | | chess.js (npm `chess.js`) | BSD-2-Clause | Rules and move generation. | | stockfish (npm `stockfish`) | GPL-3.0 | Eval bar engine (WASM, single-thread build). | | onnxruntime-web, onnxruntime-node, onnxruntime | MIT | Running the exported model. | | ChessReD dataset (4TU.ResearchData, DOI 10.4121/99b5c721-280b-450b-b058-b2900b69a90f) | CC BY-NC-SA 4.0 | Optional smoke-test data in `eval/` only. Never shipped. | | Inter Regular and Bold (npm `@expo-google-fonts/inter@0.2.3`, Inter 3.019, Copyright 2020 The Inter Project Authors) | SIL Open Font License 1.1 (text in `server/assets/fonts/OFL.txt`) | The story card's lettering, drawn by the server. The files are unmodified and ship with their licence. | | cburnett chess pieces (Colin M.L. Burnett; the set inside chessground's `chessground.cburnett.css`) | GPL-2.0-or-later (also offered under GFDL and BSD) | The 12 pieces on the story card, rasterised once to `server/assets/pieces/*.png`. | | cairosvg (PyPI) | LGPL-3.0 | Dev tool only: `server/tools/render_pieces.py` runs it through `uv run --with cairosvg` to make those PNGs. Not a dependency of the server and not deployed. | ## Required Notice (PolyForm Noncommercial) PolyForm requires that recipients get a copy of the terms or their URL () plus any plain-text lines beginning with `Required Notice:` supplied by the licensor. The GitHub `LICENSE` has none, but the `NOTICE` file shipped with the Hugging Face weights does (copied unchanged on 2026-10-18 into `third_party/chessq-lite/` and `third_party/chessqueries/`): > Required Notice: Copyright (c) 2026 Joël Seytre. The weights incorporate DINOv2 encoders (Copyright (c) Meta Platforms, Inc. and affiliates; Apache License 2.0, text in `third_party/*/LICENSE-DINOv2`). Whatever distributes the weights (the deployed app, Task 16) must ship `NOTICE` and `LICENSE-DINOv2` next to them. ## PolyForm Noncommercial License 1.0.0 (verbatim copy of the ChessQueries LICENSE file) # PolyForm Noncommercial License 1.0.0 ## Acceptance In order to get any license under these terms, you must agree to them as both strict obligations and conditions to all your licenses. ## Copyright License The licensor grants you a copyright license for the software to do everything you might do with the software that would otherwise infringe the licensor's copyright in it for any permitted purpose. However, you may only distribute the software according to [Distribution License](#distribution-license) and make changes or new works based on the software according to [Changes and New Works License](#changes-and-new-works-license). ## Distribution License The licensor grants you an additional copyright license to distribute copies of the software. Your license to distribute covers distributing the software with changes and new works permitted by [Changes and New Works License](#changes-and-new-works-license). ## Notices You must ensure that anyone who gets a copy of any part of the software from you also gets a copy of these terms or the URL for them above, as well as copies of any plain-text lines beginning with `Required Notice:` that the licensor provided with the software. For example: > Required Notice: Copyright Yoyodyne, Inc. 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Control can be direct or indirect. **Your licenses** are all the licenses granted to you for the software under these terms. **Use** means anything you do with the software requiring one of your licenses.