Privacy policy

The short version: the calculators and guides use no cookies, have no accounts and no forms, and everything you type into them stays in your browser — the calculations run locally and are never sent to any server. The exception is buying the Kit: like any online payment, it generates data on your behalf inside PayPal (your email, your name and the transaction ID), which we use to manage sales and refunds. We explain all of it below.

Who is responsible

The data controller is Rui Nunes, a private individual, publisher of Alicerce. For any privacy question or to exercise your rights, write to skyline.pt@gmail.com.

What we collect (and what we don't)

We do not collect names, emails, or the values you enter into the calculators — none of that leaves your browser. There are also no email-capture forms and no user profiles: the free checklist is a direct download, with nothing given in return.

The site itself uses no cookies or equivalent tracking technologies — that's why you don't see a cookie banner on the calculator and guide pages: it's not an oversight, it's by design. The exception is the Kit page: to process payment, that page loads PayPal's JavaScript SDK, which may set its own cookies or use its own storage, needed to process the payment securely. Those cookies are managed by PayPal, not by us, and are subject to its policy.

Visit statistics — Cloudflare Web Analytics

We use Cloudflare Web Analytics, a cookieless statistics tool with no device fingerprinting. It gives us aggregate counts (page views, country, browser type) without identifying visitors. The site is hosted by Cloudflare, Inc. (Cloudflare Workers), which processes HTTP requests like any web server — including the IP address, technically required to deliver the pages. More at cloudflare.com/privacypolicy.

Downloads and purchases — PayPal

The free checklist is a direct download from the site — we don't collect an email or any other data for you to get it.

For the Kit Compra & Construção, payment is processed entirely by PayPal, which handles the payment data (for example, the card number) as an autonomous controller, under the terms of its own policy — we never see or store that payment data.

But the purchase generates, on PayPal's side, a record with your email, your name and the transaction ID. We have access to that record — through the PayPal dashboard and through our own admin panel, which queries PayPal's Transaction Search API covering the last 30 days — and we use it to manage sales, process refunds and reissue download links when you request them. The legal basis is performance of the sale contract (GDPR art. 6(1)(b)). Our own panel shows this history for 30 days; PayPal keeps its own transaction history for longer, under its own rules and legal obligations — notably tax and fraud-prevention obligations — which we don't control. More at paypal.com/privacy.

Your rights

The GDPR gives you the rights of access, rectification, erasure, restriction, portability and objection. For the data we process because of a purchase (email, name, transaction ID), write to skyline.pt@gmail.com and we'll respond. For data that Cloudflare or PayPal process directly as autonomous controllers (for example, payment data), those rights are exercised with them — but you can always write to us and we'll help you forward the request. You also have the right to lodge a complaint with the CNPD, Portugal's data protection authority (cnpd.pt).

Changes

If this policy changes, the change will be shown on this page with the date. Last updated: 3 August 2026.