Privacy and cookie policy
We only collect the data we need to answer your message, book a call or send the newsletter. Here is exactly what happens to it.
1. Data controller
The controller of your personal data is zeroToOne sp. z o.o., registered in Warsaw, Poland, at ul. Marcina Kasprzaka 31/119, 01-234 Warszawa, NIP 5273220499, REGON 544843830 ("we"). For anything concerning your personal data, write to contact@zt1.io.
2. What data we process and why
Visiting the site
When you visit zt1.io, our hosting provider's servers automatically record technical data: IP address, browser and operating system, the page requested and the time of the visit. We use it only to run and secure the site. The legal basis is our legitimate interest (Art. 6(1)(f) GDPR).
Visitor statistics
We use Plausible Analytics and Vercel Web Analytics and Speed Insights to learn which pages are read and how quickly they load. These tools set no cookies, do not track you across sites and do not let us identify you — we only see aggregate figures. The legal basis is our legitimate interest in improving the site (Art. 6(1)(f) GDPR).
If you write to us, we process your email address, name and message to reply and to discuss a possible engagement. The legal basis is taking steps at your request before entering into a contract (Art. 6(1)(b) GDPR) or our legitimate interest in answering correspondence (Art. 6(1)(f) GDPR).
Booking a call (Calendly)
Calls are booked through a Calendly scheduler embedded in the site. You enter your name, email and possibly answers to a few questions about your project. We use them to hold and prepare for the call. The legal basis is taking steps before entering into a contract (Art. 6(1)(b) GDPR). Calendly sets its own cookies, so we only show the embedded scheduler once you consent. Without consent you can open the scheduler in a new tab, directly on calendly.com.
Newsletter
When you subscribe, you give us your email address and your role in your company. We also record the site language, the date and wording of your consent and your browser details, so that we can show consent was given. We process this data on the basis of your consent (Art. 6(1)(a) GDPR and the Polish rules on electronic communications). You can withdraw it at any time with the unsubscribe link in every email or by writing to contact@zt1.io. Withdrawal does not affect the lawfulness of processing before it.
3. Who we share data with
We do not sell data. We share it only with service providers processing it on our behalf under data processing agreements: Vercel Inc. (hosting and statistics), Plausible Insights OÜ, Estonia (visitor statistics), MongoDB, Inc. (newsletter subscriber database), Resend (email delivery), Calendly LLC (call scheduling) and our email provider. Public authorities may receive data where the law requires it.
Some of these providers are based in the United States. Transfers outside the European Economic Area rely on the European Commission's adequacy decision for the EU-US Data Privacy Framework or on standard contractual clauses approved by the Commission (Arts. 45 and 46 GDPR). You can ask us for a copy of the safeguards.
4. How long we keep data
Newsletter data — until you withdraw consent, then for the limitation period of possible claims, solely as evidence that consent was given and withdrawn. Correspondence and booked-call data — for as long as we discuss working together and, if we do not, no longer than 3 years after the last contact. Server logs — for the short period set by our hosting provider, usually a few days. If we sign a contract, we keep data for its duration and for as long as tax and accounting laws require.
5. Your rights
You have the right to access your data, to have it corrected, erased or its processing restricted, to data portability and to object to processing based on our legitimate interest. Where we process data on the basis of consent, you can withdraw it at any time. To exercise these rights, write to contact@zt1.io.
You also have the right to lodge a complaint with the Polish supervisory authority, the President of the Personal Data Protection Office (ul. Stawki 2, 00-193 Warszawa), or with the authority in your own country.
Providing data is voluntary, but without it we cannot answer your message, book a call or send the newsletter. We do not make automated decisions about you or profile you.
6. Cookies and browser storage
Cookies are small files a site stores on your device. zt1.io itself only uses those strictly necessary for it to work, which do not require consent:
NEXT_LOCALE — remembers the language version of the site you chose. Expires when you close the browser.
zt1-cookie-consent (browser local storage) — remembers your choice in the cookie banner, so we do not ask on every visit. Kept until you clear your browser data.
With your consent we show the embedded Calendly scheduler, which sets its own cookies (for sessions, security and preferences, among others) on the calendly.com domain. See Calendly's cookie policy for details.
You can change or withdraw your consent at any time with "Cookie settings" in the site footer. You can also delete or block cookies in your browser settings; blocking the necessary ones may make the site harder to use.
7. Changes to this policy
When we change how we process data, we will update this page and the date of the last change. We will email newsletter subscribers about material changes that affect them.