
Privacy policy
In short: we keep what is needed to run your account, answer your questions and build your parts. We do not sell your data and we show no advertising. You can delete your account and its data at any time from your account page → Security → Delete account, on the website or in the app.
What we collect
- Account: your e-mail address, your name if you give one, your field of work, and a salted hash of your password (never the password itself).
- What you send: your questions, the files and photos you attach, your part requests, and your projects' documents.
- What we produce for you: answers, CAD files, drawings and the previews of built parts.
- Usage: how many questions, parts and drawings you used, to apply your plan's limits.
- Sign-in sessions: a session cookie, and for each signed-in device its IP address and browser or app name, so you can see and sign out your devices.
- Payments: the plan or credits you bought, the amount, and the blockchain transaction that paid it. Payments are made in USDT; we never receive card or bank details.
- Support and feedback: the messages you send us.
Your chat history is stored in your own browser or app on your device, not on our servers.
Why we use it
- To answer your questions and build, check and deliver your parts.
- To run your account, apply your plan and credits, and confirm your payments.
- To keep the service secure (sign-in protection, abuse prevention) and to answer support requests.
- Parts that were built and passed our automatic check may be kept as worked examples that help the engine build similar parts faster. Parts built inside your private projects are only ever used for your own account. These examples are never shown to other users.
Who processes it
- AI models: to write answers and build parts, your request and attached files are sent to large-language-model providers (Google Gemini, and OpenAI for search embeddings) through an API gateway. They process them to produce the answer.
- Our build server runs SolidWorks to build your parts.
- Blockchains: USDT transfers are public on the TRON and BNB Smart Chain networks by their nature.
- Nobody else. We do not sell or rent personal data, and we use no advertising or tracking services.
Where and how long
- Our servers are in Germany.
- Your history and files are kept for the history period of your plan, then removed.
- When you delete your account, your account details, projects, files, saved parts, credits and support tickets are removed at once. Payment records are kept, without your name or e-mail, as accounting requires.
Your choices
- See and sign out your devices, change your password and turn off e-mails on your account page.
- Delete your account: account page → Security → Delete account.
- Ask us what we hold about you, or to correct it, through the support form on your account page.
Children
EngiPro is for students and professionals. It is not directed at children under 13 (16 in the European Union), and they should not create an account.
Security
Connections are encrypted (HTTPS); passwords are stored only as salted hashes; sign-in is rate-limited; only the hash of each session token is stored on the server.
Changes and contact
We will announce material changes on the site before they apply. Questions about privacy: use the support form on your account page or the contact form on engipro.tech.