Privacy
What we collect, and who else sees it.
Last updated 21 September 2026
This notice covers the tzun.ai website, our newsletter, the account portal at app.tzun.ai, and the demonstration site at demo.tzun.ai. It does not cover the records a customer captures using Tzun's product — that data belongs to the customer and is governed by their agreement with us and its data-processing terms, not by this page. If you are not sure which applies to you, ask: [email protected].
This website
The email form on the front page
The same form appears twice, near the top of the page and again at the end. If you enter your email address in either and press Get updates, two things are sent to Formspree, a form-handling service in the United States: the address you typed, and a short campaign tag taken from the ref parameter of the link you arrived on — so a visit from tzun.ai/?ref=newsletter is tagged newsletter, and a visit to a plain tzun.ai is tagged general. It tells us which announcement someone came from. Nothing else about your visit is sent, and the form is the only thing on the page that transmits anything about you.
Our lawful basis is your consent, given by submitting the form. You can withdraw it at any time: email [email protected] and we delete the address.
Fonts
Pages here load their typefaces from Google Fonts. Your browser fetches them directly from fonts.googleapis.com and fonts.gstatic.com, which means your IP address and browser user-agent reach Google when a page loads. We receive nothing from that request and cannot see it.
Analytics — there are none
We run no analytics on tzun.ai. There is no analytics script, no advertising or tracking pixel, no session recording, no fingerprinting, and the front page sets no cookies. This describes what is deployed today rather than what we intend; if we ever add analytics, this page changes before the script does.
The newsletter
If you subscribe, your email address is held by Beehiiv (United States), which sends the issues and handles unsubscribes. Every issue carries a one-click unsubscribe. We do not sell, rent or share the list.
The account portal — app.tzun.ai
Creating an account with a password collects your full name, your company name, your work email address, optionally your role at that company, and a password. The password is stored only as a hash; we never hold the password itself and cannot recover it for you.
You can sign in with Google or with GitHub instead. If you do, we receive the identity that provider returns for you — your email address and basic profile — and no password is created.
Transactional email from the portal — address verification, password resets, and notifications you have switched on — is sent through Resend (United States). The portal and its database run on Railway in the United States. Signing in sets a session cookie so the portal knows it is still you on the next page; it is required for the account to work and is not used for tracking or advertising.
Our lawful basis is performance of a contract — giving you the account you asked for — and our legitimate interest in keeping that account secure. We keep account data for as long as the account exists; ask us to close it and we delete it.
The demonstration site — demo.tzun.ai
The contact form there collects your name, email address, company and message. If you signed in with Google to reach the demo, the email address from that sign-in is stored alongside the request as well — so a request may carry two addresses if you typed a different one. Contact requests are deleted automatically 180 days after they are made. The demo also sets a session cookie so it can remember that you are signed in.
One part of the demo generates a branded walkthrough from a website address you give it. When you use it, we fetch that page and send its text to Anthropic (United States) to produce the walkthrough. Give it a company website rather than anything private: whatever is on the page you name goes to Anthropic. We do not send your name, your email address or your account there, and nothing you send is used to train models.
Who else processes your data
| Processor | What it does for us | Where |
|---|---|---|
| Cloudflare | Hosts and serves tzun.ai | United States / global edge |
| Formspree | Receives the email form on tzun.ai | United States |
| Beehiiv | Stores the newsletter list and sends it | United States |
| Railway | Runs app.tzun.ai and demo.tzun.ai and their databases | United States |
| Resend | Delivers transactional email from the portal | United States |
| Serves web fonts; sign-in, if you choose it | United States | |
| GitHub | Sign-in, if you choose it | United States |
| Anthropic | Generates the demo walkthrough from a website you name | United States |
All of them sit outside the EEA and the UK, so if you are in either, your data is transferred to the United States. Ask us and we will tell you what we rely on for each of those transfers.
Your rights
You can ask for a copy of the personal data we hold about you, ask us to correct it, ask us to delete it, ask us to restrict or stop what we are doing with it, ask for it in a portable form, and withdraw consent wherever consent is what we relied on. It costs you nothing and we will not treat you differently for asking.
Write to [email protected]. We answer within one month. If our answer does not satisfy you, you can complain to your national data protection authority.
We do not sell personal data. We do not share it for advertising. We do not use it to train models.
Changes to this notice
When it changes we update the date at the top. If a change materially affects what we do with data you have already given us, we will tell the people affected directly rather than relying on anyone re-reading this page.