Terms of Sale — UnderStack Code

Version 1.0 · valid from 25 September 2026

These terms apply when you buy a licence for UnderStack Code from understack.dk. The use of the software itself is governed by the End-User Licence Agreement (EULA), which is part of the contract.

1. Seller

UnderStack, Astridsvej 7, 8220 Brabrand (Aarhus), Denmark · CVR 46327608 · info@understack.dk · +45 91 40 67 22.

2. The product

UnderStack Code is a desktop application for macOS on Apple silicon (M1 or later) that runs AI models locally on your Mac to help you write, review and run software. The current system requirements, features and limitations are described on the product page and in the user manual. In particular:

• It requires macOS 14 (Sonoma) or later, an Apple silicon Mac and, for the recommended models, at least 16 GB of unified memory (32 GB recommended) and free disk space for the models.
• The AI models (for example gpt-oss, Gemma and Z-Image) are not included in the purchase. The app downloads them on request from their publishers, free of charge, under their own licences.
• Some optional features use third-party online services with your own account or key (for example Brave Search, Vercel). Those services are not part of the contract with us.
• AI output can be wrong. See section 9 and the AI transparency notice.

3. Price and payment

The price is EUR 50 (DKK 373 when you pay in Danish kroner) including Danish VAT (25 %), or the VAT of your EU country where that applies, as shown before you order. Business customers with a valid EU VAT number outside Denmark are invoiced without VAT (reverse charge). There are no shipping costs.

Payment is taken when you place the order, through our payment provider Revolut Business. We do not see or store your full card details.

4. The contract

The contract is concluded when you press the order button and the payment is authorised. You receive a confirmation by email with these terms, the EULA, the withdrawal information and your licence key and download link. The contract language is the language of the version of these terms you accepted (English, Danish or Spanish). We store the contract; you can request a copy at info@understack.dk.

You must be at least 18 years old to buy, or have the consent of a parent or guardian.

5. Delivery

The software is delivered digitally: a download link and a licence key are sent by email immediately after payment. The licence is perpetual: a one-time payment includes all future updates of UnderStack Code at no extra cost. Security updates are provided at least until 31 December 2031.

6. Right of withdrawal (consumers)

As a consumer you have a 14-day right of withdrawal. Because the software is digital content supplied without a tangible medium, the right of withdrawal ends when the download or installation starts, if you have (1) expressly asked us to start the supply before the withdrawal period ends and (2) acknowledged that you thereby lose your right of withdrawal, and we have confirmed this on a durable medium (the order confirmation email). Details, the model withdrawal form and the Withdraw from contract here function are in the withdrawal information.

Businesses do not have a right of withdrawal.

7. Legal guarantee (conformity)

As a consumer you have the rights of Danish consumer law (købeloven's rules on digital content) and the mandatory rules of your country of residence. We are liable if the software does not conform to the contract at the time of supply or, for updates, during the period in which we supply them. You can claim for a lack of conformity that becomes apparent within 2 years of the supply. Tell us within a reasonable time after you discover it (a notice within 2 months is always on time).

Remedies: we first bring the software into conformity (repair or update). If that is impossible, disproportionate, not done within a reasonable time or without significant inconvenience, you can ask for a price reduction or end the contract and get your money back.

We supply the updates, including security updates, that are needed to keep the software in conformity. You are not liable for a lack of conformity caused solely by not installing an update we told you about, as long as we explained the consequences of not installing it.

8. Refunds

Refunds after a valid withdrawal or after ending the contract for lack of conformity are paid within 14 days, with the same payment method, free of charge. Your licence key is deactivated and you must stop using the software.

9. AI output and your responsibility

UnderStack Code produces code, commands, texts and images with AI models. Output can be incorrect, insecure or infringe third-party rights. The app asks for your approval before editing files, running commands or publishing previews; you decide what to accept. Review and test the output before relying on it, especially before using it in production or publishing it. This does not limit your rights under section 7.

10. Liability

We are liable under the general rules of Danish law. We are not liable for indirect losses (such as lost profit, lost data or business interruption) unless caused by intent or gross negligence. Keep backups of your projects; UnderStack Code works on your files. Nothing in these terms limits liability for death or personal injury, for intent or gross negligence, under product liability law, or your mandatory rights as a consumer.

For business customers, our total liability is limited to the price paid for the licence in the 12 months before the claim, except for intent or gross negligence.

11. Personal data

We process your data as described in the privacy policy.

12. Complaints

Contact us first at info@understack.dk; we answer within 5 working days. Consumers can complain to Nævnenes Hus, Center for Klageløsning, Toldboden 2, 8800 Viborg (www.forbrug.dk). Consumers resident in another EU country can get help from the European Consumer Centre in their country.

13. Law and courts

Danish law applies, without the UN Convention on Contracts for the International Sale of Goods. If you are a consumer resident in another EU country, you keep the protection of the mandatory rules of your country, and you can bring a case before the courts where you live. For business customers, the courts of Aarhus have jurisdiction.

14. Changes

We can change these terms for future purchases. The terms accepted at the time of your purchase apply to that purchase.