Privacy, in plain words.

What we collect and why

• Email newsletter. If you subscribe, your email address goes to Kit (ConvertKit), our email provider, with double opt-in. Kit stores it and standard email data (opens, clicks) so we can send the weekly email. Every email has a one-click unsubscribe. Legal basis: your consent.
• Purchases (Pro, the $149 Cost & Stack Audit report, sponsor slots). Checkout runs on Kit’s hosted pages (o11y-watch.kit.com); card payments are processed by Kit’s payment processor, Stripe. We never see or store your card number. We receive the order record (name, email, product, amount) from Kit. Legal basis: performing the contract, plus tax and accounting duties.
• Cost audit answers stay in your browser. The audit runs entirely client-side. Your answers, any CSV you load and the generated report are kept in your browser’s session storage (o11y_audit_answers, o11y_audit_report) and are not uploaded. After a purchase, the unlock link’s token is sent once to our Cloudflare Worker to verify it, and a signed unlock proof is kept in local storage (o11y_audit_unlocked).
• Anonymous usage events, no cookies. A small first-party script (grow.js) sends events such as page views, clicks on checkout, audit or signup buttons and form submits to our own Cloudflare Worker (growth-ingest), which stores them in Cloudflare Workers Analytics Engine. Each stored event holds the site, page path, button label, UTM campaign tags, referring domain and an A/B test label. It does not include your IP address, the email you type, or any cookie or user ID. Legal basis: legitimate interest in knowing which pages help people.
• On your device. We use your browser’s local storage (not cookies) for your theme choice (t), whether you already subscribed or dismissed a prompt (o11ySub, o11yX), UTM tags for attribution (grow:utm) and A/B test assignment (grow:ab:*). Clearing site data removes all of it.
• Hosting. The site is served by Cloudflare Pages. Like any web host, Cloudflare processes your IP address to deliver pages and block abuse, under Cloudflare’s privacy policy.

What we don’t do

• No advertising trackers, no third-party analytics cookies, no selling or renting your data.
• Sponsors never receive subscriber emails.

How long we keep it

• Email: until you unsubscribe or ask us to delete it.
• Order records: as long as tax and accounting rules require.
• Anonymous events: as long as Cloudflare Analytics Engine retains them (about three months).

Your rights and deleting your data

You can unsubscribe from any email in one click. To see, correct or delete what we hold about you, email basileion.ops@gmail.com from the address concerned with the subject “Delete my data” (or “Access my data”). We remove you from Kit and delete what we are not legally required to keep, and confirm by email. If you are in the EU/UK you also have the right to object, restrict processing, data portability, and to complain to your local data-protection authority.

Changes and contact

If this page changes, the date at the top changes. Questions: basileion.ops@gmail.com. See also our terms.