Hadamard LLC

Terms

Last updated 11 October 2026

These terms cover your membership of Quantum Tycoon and your use of quantumtycoon.com. Quantum Tycoon is run by Hadamard LLC, a limited liability company formed in Wyoming, United States. "We" and "us" mean Hadamard LLC, and "you" means the member.

The short version. A membership costs US$6 a month or US$39 a year, plus any tax Gumroad adds for your country. It renews automatically until you cancel. You can cancel at any time from your Gumroad library. If you change your mind within 14 days of buying, or within 14 days of a yearly renewal, you get all your money back.

Who sells the membership

We make the course. Gumroad, Inc. sells the membership to you as our reseller and is the merchant of record. Gumroad takes the payment, issues the receipt, adds any sales tax, VAT or GST due where you live, and handles refunds on our behalf. Gumroad's own terms apply to the payment, and these terms apply to the course and the site. If the two conflict about the course, these terms win.

You must be 18 or over, or the age of majority where you live, to buy a membership. Each membership is for one person.

Price and renewal

• Monthly. US$6 charged when you buy, then every month on the same day until you cancel.
• Yearly. US$39 charged when you buy, then every year on the same day until you cancel.

Gumroad shows the tax for your country and the total before you pay. There is no minimum term. We may change the price for future periods. If we do, we will email you at least 30 days before the new price first applies to you, and you can cancel before then. Yearly members get an email reminder before each renewal, saying the date and amount and how to cancel.

Access

Gumroad emails a receipt with a licence key. You paste the key at quantumtycoon.com, and the course opens straight away. Your browser then stays signed in for up to 30 days at a time, and our server checks with Gumroad about once a day that the membership is still paid. You may use the key on your own devices. Please do not share it or post it. If a key is plainly being shared, we may switch it off, and we will email you first.

Cancelling and refunds

To cancel, sign in at gumroad.com/library with the email you paid with. Open Quantum Tycoon, choose "Manage membership" and then "Cancel membership". You can also use the link in any Gumroad receipt. No further payments are taken, and the course stays open until the end of the period you have paid for. If you cannot cancel online, email us and we will cancel it for you.

14-day money-back guarantee. If you change your mind within 14 days of your first purchase, you get a full refund. The same applies within 14 days of each yearly renewal. You do not need to give a reason. Use the withdrawal form or email us. We will refund you through Gumroad within 14 days of hearing from you, to the card you paid with, and the key then stops opening the course.

Outside those 14 days, a payment that has gone through is not refunded, except where the course was faulty or the law requires it. A monthly renewal can be cancelled at any time, so it is not refunded once it has been charged.

Your right to withdraw (EU, EEA and UK)

If you live in the European Union, the EEA or the United Kingdom, you have the right to withdraw from this contract within 14 days, without giving a reason. The 14 days run from the day of the purchase. To withdraw, tell us clearly that you wish to. You can use the "Withdraw from contract here" form, write to the address below, or email info@quantumzeitgeist.com. It is enough to send your message before the 14 days end.

If you withdraw, we refund every payment you made for the membership, without any deduction, within 14 days of receiving your message. The refund goes to the card you paid with, at no cost to you. Our money-back guarantee gives you this refund in full even though the course opened straight away, so you lose nothing by starting at once. The withdrawal right and the guarantee do not replace each other, and you may use whichever suits you.

The course

Course 1 has twelve sections. We describe what each one covers on the home page, and the course will match that description for as long as you are a member. We may correct mistakes, improve the writing or update the code to newer versions of Qiskit. If we ever make a change that takes away part of what you paid for, we will tell you at least 30 days ahead, and you may cancel and get a refund for the unused part of your period.

If the course does not work as described, tell us. We will fix it within a reasonable time. If we cannot, you are entitled to a price reduction or a refund. This is in addition to any rights you have under the consumer law where you live.

Running code

Run sends the code in the editor to our server, which runs it in Qiskit in a sealed sandbox with no network. Runs are capped at 30 an hour and 200 a day per member. Please use Run only for the course and your own experiments. Do not use it to attack the service or anyone else, to mine cryptocurrency, to get round the limits, or to run anything unlawful. We may stop runs from a key that does, and in serious cases end the membership with a refund for the unused part of the period.

Who owns what

The sections, listings, writing, images and design belong to Hadamard LLC. Your membership gives you a personal licence to use them for your own learning while the membership lasts. Please do not copy, resell or republish the course. What you learn, and the circuits you write, are yours. Qiskit is open source software, and Qiskit is a registered trademark of IBM. Quantum Tycoon is not affiliated with or endorsed by IBM.

If something goes wrong

We work to keep the site running, but it may sometimes be down for maintenance or because of faults outside our control. If you live in the EU, the EEA or the UK, we are responsible for loss you suffer that was a foreseeable result of our breaking these terms or failing to take reasonable care. We do not limit liability for death or personal injury caused by our negligence, for fraud, or for anything else the law does not let us limit.

If you live anywhere else, the course is provided as described here and, as far as the law allows, without other warranties. To the extent the law allows, our total liability to you for any claim is limited to the amount you paid us in the 12 months before the claim. Some places do not allow these limits, and then they apply only as far as the law allows.

Law and disputes

Wyoming law governs these terms. If you are a consumer living outside the United States, you also keep the protection of the mandatory consumer law of the country where you live, and you may bring a claim in the courts there. Please email us first with any complaint. We aim to reply within 5 working days. Consumers in the EU can also find help at the European Consumer Centres Network.

Changes to these terms

We may update these terms, for example when the law changes or we add a course. We will put the new date at the top. If a change affects members in a way that matters, we will email you at least 30 days before it applies, and you may cancel before then. The terms in force when you bought or last renewed apply until your next renewal.

Contact

Hadamard LLC, 1309 Coffeen Avenue, Suite 1200, Sheridan, WY 82801, United States. Email info@quantumzeitgeist.com. We reply within 5 working days.