Terms of Service

1. Purpose

These Terms of Service (the "Terms") set out the rules for accessing and using the CipherChronicle platform, available at cipherchronicle.com (the "Service"). The Service is published by Challenge My Project, a French SAS whose details appear in the legal notice.

The Service is a playful, educational platform for decoding cipher grids (wordsearch-style), covering a range of historical cryptography methods, letting users solve published grids and create their own.

2. Acceptance of the Terms

Accessing and using the Service implies full acceptance of these Terms. By creating an account or using the Service, the user declares that they have read, understood and accepted the Terms in full.

If the user does not accept the Terms, they must refrain from using the Service.

3. Access to the Service

The Service offers a free tier and paid tiers. The free tier grants unlimited access to solving public puzzles, personal progress tracking, and the editorial pages (cipher methods, use cases, FAQ). Creating and publishing puzzles, as well as creating collections, requires a paid tier as detailed in section 14 below. Access to the Service requires a modern web browser and an Internet connection.

The publisher reserves the right to modify, suspend or discontinue all or part of the Service, temporarily or permanently, without notice, in particular for maintenance or evolution purposes.

4. Account creation

Creating an account requires a valid email address, a username and a password. Authentication relies on Google Firebase. The user may also sign in through a third-party identity provider (Google, Facebook…) depending on the options the platform offers.

The user warrants that the information provided is accurate and undertakes to keep it up to date. The user is solely responsible for the confidentiality of their credentials and for any activity performed from their account.

The account is strictly personal. Any use of an account by an unauthorized third party engages the holder's liability. If fraudulent use is suspected, the user must notify the publisher without delay.

5. Use of the Service

The user undertakes to use the Service in good faith and for personal, educational or recreational purposes. In particular, the user shall not:

• interfere with the operation of the Service (attacks, unauthorized automation, malicious reverse engineering);
• attempt to circumvent security mechanisms (hash-based validation, Firestore rules, rate limits);
• mass-collect grids, accounts or Service data (scraping) without prior written authorization;
• use the Service for any illegal activity, unauthorized commercial use, or in breach of third-party rights.

6. User-generated content

Account holders may create and publish cipher grids, with an associated title, description, difficulty and hints. The user is solely responsible for the content they publish. They warrant that they hold all necessary rights (notably in the source text of the ciphered message) and that the content does not infringe any third-party rights.

The following content is notably prohibited:

• illegal, defamatory, abusive, hateful or discriminatory content;
• pornographic or violent content;
• content infringing privacy or third-party copyright;
• third-party personal data without their consent;
• unauthorized advertising, commercial or spam content.

By publishing content, the user grants Challenge My Project a non-exclusive, royalty-free, worldwide license for the duration of the Service to reproduce, represent and distribute that content strictly within the scope of running the Service (display to other users, promotion of the Service). This license does not transfer ownership: the user retains their rights.

7. Moderation and sanctions

The publisher reserves the right, without having to justify its decision, to:

• remove any content deemed contrary to these Terms, to the law or to public decency;
• temporarily suspend or permanently terminate a user account in case of repeated or serious breaches;
• report any manifestly illegal content to the competent authority.

If an account is removed, grids previously published by the user may be kept in anonymized form (detached from the account) to preserve other players' progress, unless otherwise expressly requested.

8. Intellectual property of the publisher

The Service — its architecture, source code, visual identity, logo, educational pages about cipher methods, animated demonstrations — is the exclusive property of Challenge My Project, and is protected under applicable laws, notably the French Intellectual Property Code.

Any reproduction, representation, modification, distribution or exploitation, whether total or partial, without prior written authorization from the publisher, is strictly forbidden.

9. Security and integrity of solutions

The Service's architecture ensures that a puzzle's solution is never stored in clear on the servers. Only a SHA-256 hash, computed client-side, is kept. Attempts are also validated within the user's browser.

The user undertakes not to compromise this architecture, notably through injection, bypassing of client validation, or tampering with Firestore security rules.

10. Personal data

The processing of personal data within the Service is described in the legal notice. The user holds rights of access, rectification, erasure, restriction, portability and objection under GDPR and the French Data Protection Act.

11. Availability and liability

The publisher does its best to ensure the availability of the Service but cannot guarantee absolute uptime. The Service is provided "as is", without warranty of any kind, express or implied, as to its continuity, freedom from defects or suitability for any particular purpose.

To the extent permitted by law, the publisher shall not be held liable for indirect damages arising from the use or inability to use the Service (data loss, loss of opportunity, commercial damage, etc.).

The content is provided for educational and recreational purposes. It does not constitute security advice for modern operational use: the classical ciphers presented on the Service are all breakable and must not be used to protect sensitive data.

12. Termination

The user may at any time stop using the Service and request deletion of their account from the "My account" section or by writing to the publisher. Account deletion entails the deletion of associated personal data, under the conditions described in the legal notice.

Puzzles and collections published by the user can, on request, be deleted along with the account. Absent an explicit request, they are kept in anonymized form (detached from the author’s identity) to preserve the consistency of other players’ progress. Cancelling a paid subscription has the consequences described in section 14.

13. Changes to the Terms

The publisher reserves the right to amend these Terms at any time. Account holders will be notified of substantial changes by email or by an in-app message. Continued use of the Service after notification constitutes acceptance of the new Terms.

14. Plans and subscriptions

The Service is sold under three complementary plans:

• Cipher Free (free of charge). Unlimited access to solving public puzzles, personal progress tracking, browsing the cipher method pages and the encryption workshop for discovery purposes. Does not allow publishing puzzles or creating collections.
• Cipher Publisher (€4.99 incl. VAT per month or €49.90 incl. VAT per year). Includes everything in Cipher Free, plus the ability to publish up to 20 public puzzles per billing cycle and access to aggregate completion stats for the puzzles you publish.
• Cipher Architect (€9.99 incl. VAT per month or €99.90 incl. VAT per year). Includes everything in Cipher Publisher, plus publishing private puzzles (tokenized URL), creating collections (public or private), an extended monthly quota of 50 puzzles + 1 collection per cycle, and detailed collection statistics.

The user may top up their quota by purchasing one-time credit packs:

• Pack of 10 additional puzzle publications: €1.99 incl. VAT;
• Creation of one additional collection: €0.99 incl. VAT.

Purchased credits do not reset at each billing cycle and remain usable until consumed, including after a subscription is cancelled. Conversely, the quota included with a subscription plan (20 puzzles for Publisher, 50 puzzles + 1 collection for Architect) resets at each cycle and cannot accumulate from one cycle to the next.

Payments are processed by our service provider Stripe Payments Europe Ltd, acting as a sub-processor under GDPR. CipherChronicle does not store any payment card data of its own. Paid subscriptions auto-renew at the end of each cycle unless cancelled by the user. Cancellation can be performed at any time from the "Subscription" page of the account ("Manage my subscription" button leading to the Stripe portal). It takes effect at the end of the current cycle, with no prorated refund for the unused period. Puzzles and collections already published remain online after cancellation, but no new publication is possible until the user subscribes to a new paid plan or buys additional credits.

The publisher reserves the right to amend the prices of the plans and credit packs, subject to a reasonable notice period communicated to active subscribers by email or in-app message. New prices apply only to billing cycles starting after the notification.

15. Right of withdrawal

Under article L221-18 of the French Consumer Code, a consumer is in principle entitled to a fourteen (14)-day withdrawal period from subscription to exercise their right of withdrawal in respect of a contract concluded at distance, without having to give a reason.

However, pursuant to article L221-28 13° of the same Code, this right cannot be exercised for contracts supplying digital content not delivered on a tangible medium where performance has begun after the consumer’s prior express consent and express waiver of the right of withdrawal. In practice, as soon as the user subscribes to a paid plan (Cipher Publisher, Cipher Architect) or buys a credit pack, and the corresponding quota is granted to their account immediately, performance is deemed to have started and the right of withdrawal no longer applies.

At the time of subscription, the user expressly acknowledges having been informed of this exception and consents to it by ticking the dedicated checkbox in the Stripe payment funnel. No refund may therefore be claimed for a billing cycle already started or for credits already granted, save for any mandatory provision to the contrary.

16. Governing law and jurisdiction

These Terms are governed by French law. In the event of a dispute regarding their interpretation or enforcement, the parties shall endeavor to reach an amicable solution before any judicial action. Failing agreement, the competent courts within the jurisdiction of the publisher's registered office shall have exclusive jurisdiction, unless mandatorily provided otherwise.