Privacy policy
Effective from 25 October 2026
1. Data controller
Ing. Martin Zwierzyna, Business ID: 29774161
Email: hello@martinzwierzyna.cz
Data Box ID: da88gin
For any question regarding the processing of personal data, contact me at the email above.
2. What data I process and why
Traffic analytics (Google Analytics 4) — only if you give consent in the cookie banner. Data about your device and browser, approximate location (city / country level), traffic source, viewed sections and time spent on the site are processed via a pseudonymous identifier stored in cookies. The purpose is to understand how the site is used and to improve it. The legal basis is your consent (Art. 6(1)(a) GDPR). Google Analytics 4 does not store IP addresses.
Storing your cookie choice — a technical cookie remembering whether you accepted or rejected. The legal basis is my legitimate interest in documenting consent and in the proper functioning of the site (Art. 6(1)(f) GDPR).
Technical delivery of the site — on every visit your IP address and request data are necessarily processed by the web hosting provider (server logs). The site loads no third-party resources, except Google Analytics once you give consent. The legal basis is legitimate interest in the secure and functional operation of the site.
Email communication — if you write to me, I process your email address and the content of your message in order to reply (legitimate interest, or pre-contractual steps).
3. Cookies and browser storage
| Cookie | Purpose | Duration |
|---|---|---|
cc_cookie | Stores your cookie banner choice (necessary) | 6 months |
lang | Selected site language, kept in the browser's local storage (necessary) | until deleted |
_ga | Google Analytics — distinguishes visitors (with consent) | 2 years |
_ga_9CZFX4ZHFB | Google Analytics — session state (with consent) | 2 years |
Until you give consent, Google Analytics is not loaded at all. You can change or withdraw your consent at any time: . Withdrawing consent deletes the analytics cookies; it does not affect the lawfulness of processing before withdrawal.
4. Recipients and transfers outside the EU
Analytics data is processed on my behalf by Google Ireland Limited (Gordon House, Barrow Street, Dublin 4, Ireland). Data may be transferred to Google LLC in the USA; such transfers rely on the European Commission's adequacy decision (EU-U.S. Data Privacy Framework), under which Google LLC is certified. See Google's privacy policy.
Another recipient is the web hosting provider. I do not sell or share data with any other third parties.
5. Retention
Google Analytics data is retained for 14 months and then deleted automatically. Cookie durations are listed in the table above. Email correspondence is kept as long as necessary to handle the matter.
6. Your rights
- right of access to your personal data,
- right to rectification and erasure,
- right to restriction of processing,
- right to data portability,
- right to object to processing based on legitimate interest,
- right to withdraw consent at any time,
- right to lodge a complaint with the supervisory authority — Office for Personal Data Protection (ÚOOÚ), Pplk. Sochora 27, 170 00 Prague 7, Czech Republic.
You can exercise your rights by email at hello@martinzwierzyna.cz. No automated decision-making or profiling with legal effects takes place.