Privacy Notice

Effective 24 September 2026 Applies to The Challenge (thechallenge.day) and every game served from it

1.Who is responsible

ControllerStefan Topalov, Bulgaria, operating the site as a private individual
Contactstefan_topalov@yahoo.com
Supervisory authorityCommission for Personal Data Protection (CPDP), Sofia, Bulgaria — cpdp.bg

Requests concerning your personal data can be sent to the contact address above and will be answered within one month, as Regulation (EU) 2016/679 (the GDPR) requires.

2.What this notice covers

This notice describes the personal data processed by The Challenge, the puzzle website named above, also reached through games-portal.stefantopalov.workers.dev (the "Site"), including every game reached from it and the History page. It does not cover Google's own processing when you use Google Sign-In, which is governed by Google's Privacy Policy.

3.Playing without an account

No account is needed to play. When you use the Site without signing in, the Site itself stores no personal data about you. The pages are delivered by Cloudflare, whose network keeps short-lived technical request logs (including IP addresses) for the operation and security of its service; those logs are held by Cloudflare under its own terms and are not read by the Site. The Site uses no analytics, no advertising and no third-party tracking of any kind.

4.Data processed when you sign in

Signing in is by Google Sign-In only. The following data is then held on the Site's own database.

CategoryDataSource
IdentityYour name, email address and the address of your profile picture.Google, at sign-in
Account linkAn opaque identifier linking your Site account to your Google account. The access, refresh and identity tokens issued by Google are used for the duration of sign-in and are not retained.Google, at sign-in
SessionA random session identifier and its expiry. No IP address or browser details are stored with it.The Site
PreferencesThe version of the Terms of Use you accepted and when; the games you have marked as favourites.You
Game recordsFor each daily puzzle you finish while signed in: the game, the puzzle date, your best time, the number of attempts, the number of moves where the game counts them, whether Hint or Solve was used, and the finished arrangement.Your play

Your finishing times are also counted, without your name or any other identifier, into the day's totals that every player sees as "faster than 62%" or "4th of 9 today". Nothing else is read from your Google account. No profiling takes place and no decision with legal or similarly significant effect is made about you by automated means.

5.Purposes and legal bases

PurposeData usedLegal basis
Providing your account and keeping you signed inIdentity, account link, sessionPerformance of a contract — Art. 6(1)(b) GDPR
Recording and showing your game history, your streaks, and where your time stands among the day's playersGame records (yours, and — as anonymous counts and times only — other players')Performance of a contract — Art. 6(1)(b) GDPR
Remembering your preferencesPreferencesPerformance of a contract — Art. 6(1)(b) GDPR
Evidencing acceptance of the Terms of UseTerms version and dateLegitimate interest in being able to demonstrate agreement — Art. 6(1)(f) GDPR
Security and abuse preventionSession; server-side validation of submitted resultsLegitimate interest in the integrity of the Site — Art. 6(1)(f) GDPR

No data is processed for marketing, and no data is sold or shared for any third party's own purposes.

6.Cookies and local storage

NamePurposeDuration
Session cookieHolds your random session identifier so that you stay signed in. Strictly necessary; set only after you sign in.30 days, or until you sign out
Look preference (local storage)Remembers the visual look you choose in a game. Kept only in your own browser; never sent to the Site.Until you clear your browser data

Because only strictly necessary storage is used, no consent banner is shown. No third-party cookies are set.

7.Recipients and processors

RecipientRoleSafeguard
Cloudflare, Inc.Hosts the Site and its database (Cloudflare Workers and D1).Cloudflare's Data Processing Addendum, incorporating the EU Standard Contractual Clauses
Google LLCIdentity provider for Google Sign-In.Independent controller; Google Privacy Policy

No other recipient receives personal data from the Site. Data may be disclosed where the law requires it.

8.Where data is stored

The Site's database is located in Cloudflare's Western Europe region, within the European Union. Cloudflare's global network may process requests in transit outside the EU; such transfers are covered by the Standard Contractual Clauses referenced above.

9.Retention

DataKept for
Identity, account link, preferencesAs long as your account exists
Game recordsAs long as your account exists — they are your history
Sessions30 days from last use; expired sessions are purged daily
One-time sign-in tokensMinutes; purged daily once expired

Deleting your account removes every row above immediately and permanently.

10.Your rights

Under the GDPR you have the following rights, all of which are free of charge. The first three can be exercised directly on the Site without contacting anyone.

11.Children

The Site is not directed at children and does not knowingly hold an account for anyone under 14, the age from which Bulgarian law permits a minor to agree to online services on their own behalf. If you believe such an account exists, contact the address above and it will be deleted.

12.Security

All traffic is encrypted in transit (HTTPS). Sessions are opaque identifiers that can be revoked server-side; no passwords are stored, because sign-in is delegated to Google. Submitted results are validated on the server, and only the minimum data described in section 4 is retained. Should a personal data breach occur that is likely to result in a risk to you, you will be informed as the GDPR requires.

13.Changes to this notice

This notice is updated whenever the data processed by the Site changes. The effective date at the top identifies the current version. Material changes will be indicated on the Site.