Cookie Policy

Cookie Policy for quasarium.top

Last updated: July 2026

This Cookie Policy explains what cookies are, how we use them on quasarium.top (a blog dedicated to the Lean programming language and theorem prover), and how you can control your cookie preferences. By continuing to browse our site, you agree to the use of cookies as described in this policy.

We are committed to protecting your privacy and being transparent about the technologies we use. This policy works together with our Privacy Policy (available at quasarium.top/privacy), which provides more detail on how we handle your personal data.

1. What Are Cookies?

Cookies are small text files that are stored on your device (computer, tablet, smartphone) when you visit a website. They are widely used to make websites work efficiently, improve your browsing experience, and provide information to the site owners. Cookies can be “first-party” (set by us) or “third-party” (set by external services we use).

2. Types of Cookies We Use

We use the following categories of cookies on quasarium.top:

2.1 Essential Cookies

These cookies are necessary for the basic functioning of our blog. They enable core features such as page navigation, secure access, and remembering your cookie consent preferences. Without these cookies, some parts of the site may not work properly.

• Examples: Session cookies, cookie consent preference cookies.
• Purpose: To keep the site secure and operational.
• Duration: Mostly session-based (deleted when you close your browser) or persistent for up to 12 months.

2.2 Analytics Cookies

We use analytics cookies to understand how visitors interact with quasarium.top — for example, which blog posts are most popular, how users navigate the site, and where our traffic comes from. This helps us improve the content and user experience for our Lean community.

• Examples: Google Analytics cookies (_ga, _gid, _gat).
• Purpose: To collect aggregated, anonymized data about site usage.
• Duration: Persistent (typically up to 2 years) or session-based.

2.3 Advertising Cookies

We partner with Google AdSense (a third-party advertising network) to display relevant ads on our blog. Advertising cookies are used to build a profile of your interests based on your browsing activity across different sites. This allows Google to show you ads that are more relevant to you (personalized advertising) and to measure the effectiveness of ad campaigns.

• Examples: Google AdSense cookies (e.g., _gcl_au, IDE, test_cookie).
• Purpose: Ad personalization, ad frequency capping, conversion tracking, and fraud detection.
• Duration: Persistent (typically up to 13 months, but some may expire sooner).

Please note that we do not control the data collected by Google AdSense. For more information on how Google uses your data, please review Google’s Advertising Cookies Policy.

3. How We Use Advertising Cookies (Google AdSense)

Through Google AdSense, we may show you ads that are personalized based on your previous visits to quasarium.top and other websites. These cookies:

• Track which ads you have already seen to avoid showing the same ad repeatedly.
• Measure the performance of ad campaigns (e.g., click-through rates).
• Help prevent fraudulent clicks and ensure advertising integrity.

If you do not wish to receive personalized ads, you can opt out at any time (see Section 4 below). Please note that even if you opt out of personalization, you may still see non-personalized ads based on the content of the page (contextual advertising).

4. How You Can Control Cookies

You have several options to manage or disable cookies:

4.1 Browser Settings

Most web browsers allow you to control cookies through their settings. You can:

• Block all cookies (including essential ones, which may affect site functionality).
• Delete existing cookies.
• Set your browser to notify you when a cookie is placed.

Instructions for common browsers:

• Google Chrome: Settings → Privacy and security → Cookies and other site data.
• Mozilla Firefox: Options → Privacy & Security → Cookies and Site Data.
• Safari: Preferences → Privacy → Cookies and website data.
• Microsoft Edge: Settings → Cookies and site permissions → Cookies and site data.

4.2 Opt-Out of Ad Personalization

To opt out of personalized advertising from Google AdSense, you can:

• Visit Google’s Ad Settings page (adssettings.google.com) and toggle off “Ad Personalization.”
• Use the Digital Advertising Alliance’s opt-out tool (optout.aboutads.info) to manage preferences across multiple ad networks.

If you opt out, Google will still serve ads on quasarium.top, but they will be non-personalized (based only on the content of the page).

4.3 Cookie Consent Banner

When you first visit quasarium.top, you will see a cookie consent banner. You can accept all cookies, reject non-essential cookies (analytics and advertising), or customize your preferences. Your choice will be remembered for up to 12 months.

5. Third-Party Cookies

In addition to Google AdSense, we may embed content from other third-party services (e.g., YouTube videos, GitHub code snippets). These services may set their own cookies, which are governed by their respective privacy policies. We encourage you to review the cookie policies of any third-party services you interact with on our site.

6. Changes to This Cookie Policy

We may update this Cookie Policy from time to time to reflect changes in technology, legislation, or our data practices. Any changes will be posted on this page with an updated “Last updated” date. We encourage you to review this policy periodically.

7. Contact Us

If you have any questions about this Cookie Policy or our data practices, please contact us:

Email: [email protected]
Website: quasarium.top
Privacy Policy: quasarium.top/privacy

We are based in the European Union and comply with applicable data protection laws, including the GDPR and ePrivacy Directive.