Legal

Privacy Policy

Last updated: April 27, 2026

Delta-V Academy (the "Service") is an educational orbital mechanics simulator operated by BuildingRome. This policy describes what information the Service collects, how it is used, and the third parties involved. Using the Service means you accept the practices described here.

1. Summary

  • No account, sign-in, or personal profile is required to use the Service.
  • No marketing cookies. No advertising trackers. No data brokers.
  • We collect anonymous, aggregated usage analytics so we can understand how the site is used and keep it working.
  • Lesson progress and UI preferences are stored on your device, not on our servers.
  • Prompts you submit to the AI Mission Architect are sent to Google Gemini for processing.

2. Information We Collect

2.1 Usage analytics (PostHog and Vercel)

The Service uses two analytics tools to understand how the product is used:

  • PostHog captures named interaction events and page views. We use it with autocapture disabled, meaning only the specific events listed below are recorded. PostHog uses browser localStorage (not cookies) for session persistence. No personal profile is built for unauthenticated users. Events we capture include:
  • Page views and page-leave events
  • Lesson menu opened, lesson selected (lesson ID and title), lesson completed
  • Difficulty level selected (novice, intermediate, or advanced)
  • Mission changed (mission ID)
  • Time-speed control used (speed multiplier)
  • AI Architect modal opened
  • Replay menu opened, replay started (replay ID and title)
  • Help / Info modal opened
  • Screenshot taken (resolution setting); video recording started and stopped (resolution and duration)
  • Global overlay controls toggled (control name and on/off state)
  • Feedback button clicked (current mission, lesson, and level — no free-text content)
  • Simulator error boundary triggered (error name and message)

Each event may include browser type, approximate geographic region (country and city level), device category, and operating system as inferred by PostHog from your request headers.

  • Vercel Analytics measures page views and Core Web Vitals (performance signals). It is cookie-less and does not collect personally identifying information. Aggregated metrics include approximate region, device type, browser, and referrer.

2.2 Local storage on your device

The Service uses the browser's localStorage and sessionStorage to remember settings such as lesson progress, difficulty level, panel layout, and the welcome modal dismissal state. PostHog also uses localStorage (key prefix ph_) to persist an anonymous session identifier between page loads. This data lives on your device only. Clearing your browser storage erases it.

2.3 AI Mission Architect prompts

If you use the AI Architect feature, the natural-language prompt you type is transmitted to Google's Gemini API to generate a mission configuration. We do not store these prompts on our servers, but Google may process and retain them under Google's Privacy Policy. Do not include personal, confidential, or proprietary information in Architect prompts.

2.4 Server logs

Our hosting provider (Vercel) maintains standard server logs that may include IP address, request path, user-agent, and timestamps. These logs are used for security, abuse prevention, and operational diagnostics, and are retained per Vercel's policies.

3. What We Do Not Collect

  • We do not collect names, email addresses, phone numbers, or postal addresses through the Service.
  • We do not run advertising networks or sell data to third parties.
  • We do not fingerprint users or build cross-site profiles.
  • We do not require or process payments through the Service.
  • We do not capture free-text input from sliders, lesson content, or the 3D view.

4. Cookies and Local Storage

The Service does not set advertising or tracking cookies. PostHog stores an anonymous session identifier in your browser's localStorage (not as a cookie) under keys prefixed with ph_. Vercel may set a small number of essential, first-party operational cookies for hosting and performance measurement. None of these contain personal information or are used for advertising purposes.

5. Third-Party Services

We rely on a small number of third parties to operate the Service:

  • PostHog provides product analytics and event tracking. See PostHog's Privacy Policy. PostHog is configured with person_profiles: 'identified_only', meaning no persistent user profile is created for unauthenticated visitors.
  • Vercel hosts the application and provides performance analytics. See Vercel's Privacy Policy.
  • Google (Gemini API) processes prompts you send to the AI Mission Architect. See Google's Privacy Policy.
  • Open data sources such as CelesTrak, Space-Track, NASA, ESA, and similar public catalogs may be fetched to populate orbital element references. Requests are made server-side and do not transmit user-identifying data.

6. Children's Privacy

The Service is intended for general audiences interested in learning orbital mechanics, including students. We do not knowingly collect personal information from anyone, including children under 13. Because we do not require accounts and do not collect contact information, the Service is designed to be usable without disclosing personal data. If you believe a child has somehow provided personal information through the Service, contact us and we will remove it.

7. Data Retention

PostHog event data is retained per PostHog's default retention policy (currently one year for free-tier projects; subject to change). Aggregate Vercel Analytics are retained per Vercel's policies. Local-storage values persist on your device until you clear them. Architect prompt content is not retained on our servers.

8. Security

We use commercially reasonable measures to protect the Service. No method of transmission or storage is perfectly secure, and we cannot guarantee absolute security. Use the Service understanding this limitation.

9. International Users

The Service is operated from the United States. PostHog infrastructure used is in the US region (us.i.posthog.com). If you access the Service from elsewhere, you consent to the transfer and processing of information in the United States and other regions where our service providers operate.

10. Your Choices

  • You can clear your browser's site data at any time to remove all locally stored preferences and PostHog session identifiers.
  • You can opt out of PostHog analytics at any time by enabling Do Not Track in your browser, or by using an analytics-blocking extension. PostHog respects the DNT header.
  • You can opt out of Vercel Analytics with browser-level tracking protection or an ad blocker.
  • You can choose not to use the AI Architect, in which case no prompt data is generated or transmitted.

11. Changes to This Policy

We may update this policy as the Service evolves (for example, when account authentication is added, data collection practices will change and this policy will be updated accordingly). Material changes will be reflected by updating the "Last updated" date at the top of this page. Continued use of the Service after an update means you accept the revised policy.

12. Contact

Questions about this policy can be sent to info@buildingrome.dev. See the Contact page for more options.