Terms of use

1. Purpose

These terms govern access to and use of Blunderland. Blunderland is a free chess trainer that fetches your Chess.com or Lichess games and turns each of your blunders into a puzzle to work on.

2. Acceptance

Using the service means you fully accept these terms. If you disagree with any of them, do not use the app.

3. The service

The service is entirely free: no paywall, no purchase, no paid feature. From a public username, it lets you:

• fetch your recent games from Chess.com or Lichess,
• detect your blunders through a Stockfish analysis running in your browser,
• replay those positions as puzzles, with scoring and spaced repetition.

4. Access and account

Blunderland works without an account: your data then stays in your browser. An optional account (email code or Google sign in) enables synchronized saving across your devices.

You are responsible for access to the email inbox you use to sign in. Any action taken from your account is deemed to be taken by you.

5. Acceptable use

You agree not to:

• divert the service from its purpose or disrupt its operation,
• overload, bypass or abuse the Chess.com and Lichess APIs,
• attempt to access data that is not yours,
• analyze another person's username in order to harm them,
• use the service for unlawful purposes.

You also agree to comply with the terms of use of Chess.com and Lichess.

6. Chess.com and Lichess

Blunderland is neither affiliated with, nor endorsed or sponsored by Chess.com or Lichess. Games and game data belong to those platforms and their users. We only use their public APIs, in compliance with their terms.

7. Intellectual property

The Blunderland name, its visual identity and its source code are protected. Your use of the service transfers no ownership rights over these elements to you.

Blunderland relies on third party software (including chess.js and Stockfish) distributed under their own licenses, which you agree to comply with.

8. Service provided as is

The service is provided as is and as available, without any guarantee of continuous operation or absence of errors. Analyses rely on a chess engine: they provide an estimate, not an absolute truth. The service may change, be suspended or discontinued at any time.

9. Liability

To the extent permitted by law, the publisher cannot be held liable for indirect damages resulting from the use of, or inability to use, the service. As the service is free, the publisher is not responsible for the loss of data stored locally in your browser: remember to create an account to back it up.

10. Personal data

The processing of your personal data is described in the Privacy policy, accessible from the footer.

11. Third party services

The service relies on third party providers and services (hosting, analytics, chess platforms) that the publisher does not control and is not responsible for.

12. Changes to the terms

These terms may be updated. The last updated date appears at the top of this page. Continuing to use the service after a change means you accept the new version.

13. Termination

You may stop using Blunderland at any time and delete your account or your data. The publisher may suspend access in case of abuse or breach of these terms.

14. Governing law and disputes

These terms are governed by French law. In case of a dispute, an amicable solution will be sought first. Failing that, and if you are a consumer, you may use a consumer mediator or the European online dispute resolution platform free of charge. The French courts have jurisdiction.