Public offer

The following terms are used in this Offer with the meanings given below, unless the context explicitly requires otherwise:

The Provider grants the User access to the Service for learning and practising Structured Query Language (SQL) to the extent defined by the chosen Plan, and the User undertakes to pay for the Services under the terms of this Offer.

The Service provides: a task catalogue (including problems from real job interviews), a training sandbox with automatic grading against hidden data, role-based learning tracks, a Mock Interview mode with a server-side timer and browser lockdown, a progress and ranking system ("Power" points, ranks, achievements, a weekly leaderboard, leagues, friends), AI-based task and hint generation and an AI mentor, and other features described on the Site.

Some features are available free of charge; extended functionality is provided as part of the Premium Subscription per Appendix 1 to this Offer.

Acceptance is deemed to occur when the User performs any of the following: (a) registers on the Site; (b) pays for any Plan. Either action constitutes full and unconditional agreement to this Offer.

Upon Acceptance the Agreement is deemed concluded in electronic form and has the same legal force as a paper document signed by the parties (Art. 434 of the Russian Civil Code).

Registration is possible by providing an email and password, or via third-party services (Google, GitHub, Yandex). The User confirms they are at least 18 years old and have full legal capacity.

The User undertakes to provide accurate information and is solely responsible for keeping their password safe. All actions performed under the account are deemed to have been performed by the User.

Account sharing is prohibited. If unauthorised access is suspected, the User must promptly change their password and notify the Provider.

Service prices are set in Russian rubles; the ruble is the currency of obligation (Art. 317 of the Russian Civil Code). Payment is made via the YooKassa payment service (YooMoney NBCO LLC) and other payment methods available on the Site at the time of checkout. A fiscal receipt is generated automatically in accordance with Federal Law No. 54-FZ and sent to the User's email.

If the User pays for the Services in a foreign currency (e.g. US dollars) via a payment service available on the Site, the amount charged is calculated by that service at its exchange rate at the time of payment. The User's payment obligation is deemed fulfilled once funds equivalent to the ruble price of the chosen Plan are credited to the Provider's account. Exchange-rate differences and currency-conversion fees are borne by the User. Any foreign-currency amounts shown on the Site are for reference (informational) purposes only.

The User's payment obligation is fulfilled once funds are credited to the Provider's account. Premium access is activated automatically upon successful payment.

All Premium Plans are paid in a single transaction covering the full term. No auto-renewal — bank-card credentials are not stored and are never reused for recurring charges. When the paid period ends Premium access stops, and the User may purchase a new term manually from the Pricing page.

The User has the right to cancel the Subscription and request a 100% refund within 7 calendar days of the first Subscription payment, provided the User has not used any paid Premium features (no AI task generation, no attempts at Premium-marked tasks, no access to community solutions, no Mock Interview sessions beyond the free daily limit).

If the User has already used paid features within the first 7 days, or the refund window has expired, no refund is issued for the paid and consumed period. This aligns with Russian consumer-protection law for services of an individual nature.

Refund requests are sent in free form to coderang.dev@gmail.com with the account email, payment date, and transaction ID. Refunds are issued to the same bank card used for payment within up to 10 calendar days of receiving a valid request.

All Service materials — texts, tasks, reference solutions, datasets, code, design, visuals and trademarks — are the exclusive property of the Provider or are used by the Provider on a lawful basis.

The User is granted a limited, non-transferable licence to use the materials strictly for personal learning purposes within the Service.

Copying, publishing, distributing, or adapting reference solutions and other Service materials for commercial or public purposes is prohibited. In case of a breach, the Provider may claim statutory damages under Art. 1301 of the Russian Civil Code ranging from RUB 250,000 to RUB 5,000,000 per violation.

SQL queries authored by the User while solving tasks belong to the User. The User grants the Provider a royalty-free, non-exclusive licence to process and store them to the extent necessary to operate the Service (grading, statistics, personal progress).

The AI task-generation, AI-hint, and AI-mentor (chat assistant) features use third-party language models (OpenAI, Anthropic). When these features are used, request contents (topic, difficulty, task context, the User's question text) are transmitted to the chosen provider to generate a response. The text of the User's SQL queries may be transmitted to the provider only to the extent needed to analyse a specific error and only at the User's own initiative.

AI-generated content is provided "as is". The Provider does not warrant accuracy, correctness, or suitability for any particular expectation. Decisions made by the User based on AI recommendations are made at the User's own risk.

The Service is provided "as is". The Provider does not warrant uninterrupted operation and is not liable for inability to use the Service due to causes outside the Provider's control (lack of connectivity, provider outages, issues with the User's device).

The Provider's aggregate liability to the User for all claims arising from the Agreement is limited to the amounts actually paid by the User under the Agreement during the 12 (twelve) months preceding the event giving rise to the claim.

The Provider is not liable for indirect damages, lost profits, data loss, reputational harm, or other consequential losses arising from use of or inability to use the Service.

The parties are released from liability for partial or total non-performance where it is caused by force majeure: natural disasters, armed conflict, epidemics, acts of state authorities, material legislative changes, or outages of critical infrastructure providers (DNS, CDN, payment systems, data centres).

The party affected by force majeure must notify the other party within a reasonable time, but no later than 7 (seven) calendar days from the event.

The Provider processes personal data in accordance with the Privacy Policy available at /privacy. By Accepting this Offer, the User confirms familiarity with the Policy and consents to the processing of their personal data for the purposes stated therein.

This Offer is in force from its posting on the Site until withdrawn by the Provider or replaced by a new version.

The Provider may unilaterally amend this Offer by publishing a new version on the Site. A new version takes effect no earlier than 5 (five) business days after publication. Continued use of the Service after the effective date constitutes User's consent to the new version.

Where amendments materially worsen the User's position, the User may terminate the Agreement with a pro-rata refund for the unused Subscription period by giving notice within 30 (thirty) calendar days of publication.

All disputes arising from the Agreement are first resolved through negotiation. A pre-trial claim procedure is mandatory: claims are reviewed within 30 (thirty) calendar days from receipt. Claims are sent in written form to coderang.dev@gmail.com.

Failing amicable resolution, disputes are submitted to the court at the consumer-User's place of residence under Russian consumer-protection law, or to the court at the Provider's place of registration for other Users.

If any provision of this Offer is held invalid, the remaining provisions remain in force. The parties shall replace the invalid provision with a valid one closest to its economic intent.

Notices and other correspondence between the parties are sent: to the Provider — to the email in Section 16; to the User — to the email provided at registration.