Terms of Service

Last updated September 28, 2026

These Terms of Service (“Terms”) are an agreement between you and Virtual Metrics LLC (“we,” “us,” or “our”), which operates Nodes & Nines at nodesandnines.com (the “Service”). By signing in to or using the Service, you agree to these Terms and acknowledge our Privacy Policy. If you don’t agree, don’t use the Service.

1. Eligibility

You must be at least 18 years old and able to form a binding contract to use the Service. You may not use the Service if you’re prohibited from doing so under applicable law, including U.S. sanctions and export laws.

2. Your account

You sign in to the Service with a Google account. You’re responsible for all activity under your account and for keeping your Google account secure. Your account is for you alone: don’t share it or let anyone else use it. If you think someone has accessed your account without permission, email us at support@nodesandnines.com.

3. The Service

Nodes & Nines helps you practice system design interviews: you work through problems on a whiteboard, phase by phase, and can request AI-generated feedback on each phase.

• Free access: some problems are available without a subscription, with limits shown in the Service (currently one attempt each at two problems).
• Subscriptions: a subscription unlocks all problems and retakes.
• Usage limits: to keep the Service available and affordable, we limit some features, such as the number of feedback requests per phase. Current limits are shown in the Service.
• Changes: we may add, change, or remove problems and features. If we discontinue the Service entirely, we’ll refund the unused portion of any prepaid subscription.

4. AI-generated feedback

Scores, summaries, and other feedback in the Service are generated automatically by AI models. Feedback can be inaccurate, incomplete, or inconsistent, and the same work may receive different feedback at different times. Feedback is for practice only. It isn’t professional advice, a hiring assessment, or a prediction of how any employer will evaluate you, and we don’t guarantee any interview outcome or job offer. Use your own judgment about how much to rely on it.

5. Subscriptions, billing, and cancellation

• Checkout through Link: subscriptions are sold through Link, Stripe’s checkout service, which acts as the merchant of record for your purchase. Link’s terms and privacy policy also apply to your payment, Link sends your receipts, and charges appear on your statement as LINK.COM* followed by our name. We provide the Service under these Terms.
• Price and billing period: the price and billing period of each plan are shown before you subscribe. Prices are listed in U.S. dollars; at checkout you may be shown and charged the equivalent amount in your local currency.
• Automatic renewal: your subscription renews automatically at the end of each billing period for another period of the same length, at the then-current price, until you cancel. By subscribing, you authorize Link to charge your payment method at the start of each billing period.
• Cancellation: you can cancel online at any time. Open the Billing page and choose “Manage or cancel subscription.” Cancellation takes effect at the end of your current billing period; you keep access until then and won’t be charged again. You can also manage your subscription from your Link account.
• Refunds: payments are non-refundable, and we don’t provide refunds or credits for partial billing periods, except where required by law. Link may also handle refund requests about a charge under its own policies.
• Price changes: we may change subscription prices. We’ll email you at least 10 days before a new price applies to your subscription, and you can cancel before it takes effect.
• Failed payments: if a payment fails, it may be retried. If payment can’t be collected, we may suspend or end your subscription.
• Taxes: prices don’t include taxes unless stated. Applicable sales tax, VAT, or similar taxes are calculated and added at checkout.
• Promotions: if we offer a free trial, discount, or other promotion, its terms will be shown when you sign up for it.

6. Your content

“Your content” means the whiteboards and anything else you create or submit in the Service. You own your content. You give us a worldwide, non-exclusive, royalty-free license to host, store, copy, process, display, and transmit your content only as needed to provide and operate the Service for you, including sending it to our AI providers to generate your feedback, and as described in our Privacy Policy. This license ends when your content is deleted, except for backup copies that expire on their normal schedule and copies we’re legally required to keep.

You’re responsible for your content and confirm that you have the right to submit it. Don’t include confidential information you’re not allowed to share, such as your employer’s non-public designs, or sensitive personal information.

You may use the feedback generated for your content for your own interview preparation. If you send us suggestions or ideas about the Service, we may use them without any obligation to you.

7. Our content and trademarks

The Service, including its problems, problem details, key points, rubrics, hints, software, design, and the Nodes & Nines name, belongs to us or our licensors and is protected by intellectual property laws. Subject to these Terms, we give you a limited, personal, non-exclusive, non-transferable, revocable license to use the Service for your own interview preparation. You may not copy, publish, sell, or redistribute our problem content or generated feedback in bulk, or use them to build a competing product or dataset.

Problem titles may mention well-known companies and products, such as Twitter, WhatsApp, Uber, or YouTube, only to describe the practice scenario. Those names are trademarks of their owners, who aren’t affiliated with and don’t endorse Nodes & Nines.

The whiteboard is built on Excalidraw, open-source software available under the MIT License.

8. Acceptable use

You agree not to:

• use the Service in a way that breaks the law or violates anyone’s rights;
• share, sell, or transfer your account or subscription, or let others use it;
• get around access controls, paywalls, usage limits, or security measures;
• scrape, crawl, or use bots or other automated means to access the Service or copy its content;
• reverse engineer the Service or try to extract its source code, prompts, or underlying models, except where the law allows;
• try to manipulate the AI feedback into revealing its instructions or producing content unrelated to interview practice;
• upload malware or content that is unlawful, infringing, harassing, or harmful;
• disrupt the Service or other users, or probe or test its vulnerabilities without our written permission; or
• use the Service or its output to develop or train a competing product or AI model.

9. Third-party services

Sign-in is provided by Google, and purchases are sold and processed through Link and Stripe, under their own terms and privacy policies. We aren’t responsible for third-party services.

10. Suspension and termination

You can stop using the Service at any time, and you can ask us to delete your account as described in our Privacy Policy. We may suspend or end your access if you violate these Terms, if the law requires it, or if needed to protect the Service or other users; where reasonable, we’ll tell you first. If we end your access without cause, we’ll refund the unused portion of any prepaid subscription. Sections that by their nature should survive termination, including Sections 6, 7, and 11 through 16, will survive.

11. Disclaimers

THE SERVICE, INCLUDING ALL CONTENT AND FEEDBACK, IS PROVIDED “AS IS” AND “AS AVAILABLE,” WITHOUT WARRANTIES OF ANY KIND, WHETHER EXPRESS OR IMPLIED, INCLUDING IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE, AND NON-INFRINGEMENT. WE DON’T WARRANT THAT THE SERVICE WILL BE UNINTERRUPTED, SECURE, OR ERROR-FREE, THAT FEEDBACK WILL BE ACCURATE, OR THAT YOUR CONTENT WILL NEVER BE LOST.

Some jurisdictions don’t allow the exclusion of certain warranties, so some of these exclusions may not apply to you.

12. Limitation of liability

TO THE FULLEST EXTENT PERMITTED BY LAW, WE WILL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, EXEMPLARY, OR PUNITIVE DAMAGES, OR FOR ANY LOSS OF PROFITS, REVENUE, DATA, OR OPPORTUNITIES (INCLUDING EMPLOYMENT OPPORTUNITIES), ARISING OUT OF OR RELATING TO THE SERVICE OR THESE TERMS. OUR TOTAL LIABILITY FOR ALL CLAIMS ARISING OUT OF OR RELATING TO THE SERVICE OR THESE TERMS WILL NOT EXCEED THE GREATER OF THE AMOUNT YOU PAID US IN THE 12 MONTHS BEFORE THE EVENT GIVING RISE TO THE CLAIM OR US $50. THESE LIMITS APPLY TO ANY THEORY OF LIABILITY, EVEN IF WE WERE TOLD SUCH DAMAGES WERE POSSIBLE.

Some jurisdictions don’t allow these limitations, so they may not apply to you.

13. Indemnity

You’ll defend, indemnify, and hold harmless Virtual Metrics LLC and its members and managers from any claims, losses, and expenses (including reasonable attorneys’ fees) arising from your content, your violation of these Terms, or your violation of any law or anyone else’s rights.

14. Governing law and disputes

If you have a dispute with us, please email support@nodesandnines.com first, and we’ll try to resolve it informally within 30 days. These Terms are governed by the laws of the State of Washington and applicable U.S. federal law, without regard to conflict-of-laws rules. Any dispute arising out of or relating to these Terms or the Service will be resolved exclusively in the state or federal courts located in the State of Washington, and you and we consent to their personal jurisdiction, except that either of us may bring an individual claim in small claims court if it qualifies. This section doesn’t take away any protections you have under the consumer laws of the state where you live.

15. Changes to these Terms

We may update these Terms from time to time. We’ll post the updated Terms here with a new “Last updated” date and, for material changes, notify you by email or in the Service at least 10 days before they take effect. If you keep using the Service after the changes take effect, you agree to the updated Terms; if you don’t agree, stop using the Service and cancel your subscription. Changes won’t apply to disputes that arose before they took effect.

16. General

• These Terms and our Privacy Policy are the entire agreement between you and us about the Service.
• If any part of these Terms is found unenforceable, the rest stays in effect. Our failure to enforce a provision isn’t a waiver of it.
• You may not transfer these Terms without our consent. We may transfer them as part of a merger, acquisition, or sale of our business or assets.
• We aren’t responsible for delays or failures caused by events beyond our reasonable control.
• We may send notices and other communications electronically, by email or in the Service, and they satisfy any requirement that communications be in writing.

17. Notice to California users

Under California Civil Code Section 1789.3, California users are entitled to the following notice. The Service is provided by Virtual Metrics LLC, which you can reach by email at support@nodesandnines.com. Subscription prices are shown in the Service before you subscribe. To resolve a complaint about the Service, contact us the same way. You may also contact the Complaint Assistance Unit of the Division of Consumer Services of the California Department of Consumer Affairs in writing at 1625 North Market Blvd., Suite N-112, Sacramento, CA 95834, or by telephone at (800) 952-5210.

18. Contact

Questions about these Terms? Contact us by email at support@nodesandnines.com. Nodes & Nines is operated by Virtual Metrics LLC.