Privacy Policy

Effective 2026-08-12

What this site is

Repertoire Builder is a set of static pages showing chess opening and rating statistics computed from Lichess’s public API and Opening Explorer. There are no user accounts, no logins, and no forms that collect personal information anywhere on this site (the player-lookup page sends only the Lichess username you type directly to Lichess’s own public API, from your browser — this site’s own servers never see or store it).

Analytics

This site uses GoatCounter, a privacy-focused analytics tool, to count page views. GoatCounter’s default configuration does not use tracking cookies and does not collect personally identifying information; it records aggregate counts of visits, pages viewed, and referring sites. See GoatCounter’s own privacy policy for exactly what it collects and retains.

Advertising

This site runs Google AdSense. Google and its advertising partners may use cookies or similar identifiers to show ads based on your visits to this and other sites. You can see and control what Google knows for ad personalization at Google’s Ad Settings, and read more about how this works at how Google uses information from sites that use its services and how Google uses data in advertising. This site’s own code does not read, set, or have access to any AdSense cookie or identifier — that data goes directly between your browser and Google.

Third-party links

Pages on this site link out to lichess.org for game analysis and data, and to voluntary support links (Ko-fi, Buy Me a Coffee). Each of those is operated by its own company under its own privacy policy — review theirs before using them. See the disclosure note in this site’s footer for more on those links.

Cookies

This site’s own code does not set any cookies. GoatCounter’s default configuration (described above) is cookieless. Google AdSense (described above under Advertising) does use cookies or similar identifiers, set directly by Google, not by this site — see the Advertising section above for how to control that.

The opening drill saves your progress (which level you have reached) in your own browser using local storage. That data never leaves your device, is not a cookie, is not sent to us or anyone else, and clearing your browser data removes it.

Children’s privacy

This site is not directed at children and does not knowingly collect information from anyone under 13.

Changes to this policy

This policy may be updated as the site changes (for example, if advertising or new analytics are added). The effective date above reflects the most recent update.

Contact

Questions about this policy? See the Contact page.