Terms of Service

Last updated: November 4, 2026

These terms apply when you use leandatascientist.com, its Vibe Coding course at learn.leandatascientist.com and its MCP servers (together, "the service"), run by Duodecimal, LLC, a California limited liability company, as Lean Data Scientist ("we", "us"). By creating an account or buying the 3-Month Pass, you agree to them. Our Privacy Policy explains how we handle your information.

Your account

You must be 16 or older to use the service.
You sign in through Clerk. Keep your sign-in secure: you are responsible for what happens under your account.
An account is for one person. Do not share your account or your Pass with anyone.

What is free and what the Pass includes

Every account gets the first data exercise, with its analysis sandbox, and the preview chapter of the Vibe Coding course for free.
The 3-Month Pass covers the analysis sandbox of every data exercise and the full Vibe Coding course, for 3 months from the moment your payment goes through. Buying another Pass while one is active moves its end date 3 months later.
The Pass is a one-time payment, not a subscription: it does not renew, and you are not charged again unless you buy another. The price is on the pricing page. Payments are taken by Stripe; we never see your card details.

Refunds

All sales are final. The Pass starts as soon as your payment goes through, so payments are not refunded, in whole or in part, including for any part of the 3 months you do not use.
Before you buy, try the free data exercise and the course's preview chapter to see whether the Pass is right for you.
If you were charged twice for the same purchase, or charged without getting your Pass, write to support@leandatascientist.com from your account's email address, and we will refund the extra charge or turn on your Pass. Please contact us before disputing a charge with your bank: we can usually fix a billing problem faster.
Nothing in these terms limits rights you have under the consumer protection laws that apply to you.

Using the sandbox and the exercises

The data exercises and their datasets are for your own practice. The data stays in the sandbox: you query it through your own AI agent, within the limits stated on the site, such as rows per query and a daily allowance.
Do not try to copy, download or rebuild the datasets in bulk, get around the limits, open exercises you do not have access to, or interfere with the service.
Do not republish, share or sell the exercises, their datasets or the course.

Your AI agent

You connect your own AI client, such as Claude, ChatGPT or Cursor. Its provider's terms govern your use of it, and its output is its own, not ours. Every query and every piece of code your agent runs in our sandbox is logged, to enforce the limits and keep the service safe; see the Privacy Policy.

Our content

The exercises, datasets, course and site belong to us or our licensors. Using the service does not give you ownership of them. Company names in the exercises are fictional.

Suspension

We may suspend or close an account that breaks these terms, for example by sharing it or extracting data in bulk. An account closed for breaking these terms is not refunded.
You can stop using the service at any time. To delete your account, contact us.

No guarantees

The service is provided as is. We work to keep it available and correct, but we do not promise it will be uninterrupted or free of errors, or that using it will lead to any interview result or job offer.
To the extent the law allows, we are not liable for indirect or consequential losses, and our total liability for any claim is limited to what you paid us in the 12 months before it.

Changes to these terms

We may update these terms. We will change the date above and tell signed-in users about significant changes. Using the service after a change means you accept the updated terms. Changes do not shorten a Pass you have already bought.

Contact

Duodecimal, LLC (Lean Data Scientist)
support@leandatascientist.com