The Plunge Lab

What we collect, and where it goes.

This page describes what this site actually does, checked against the code that does it. Where a normal privacy policy would hedge, we would rather be narrow and specific — the same standard as the rest of the site.

Last updated 8 September 2026.

If you sign up for the Sunday Brief

The form takes your email address. When you submit it, three things are sent to the site owner as a single notification email: the address you typed, which page you submitted it from, and the IP address the request arrived from.

There is no subscriber database on this site. Your address is not written to a table, not synced to a marketing platform, and not enriched against anything. It arrives as an email and sits in a mailbox. That is the whole mechanism.

The notification is delivered by Resend, an email provider, which handles the message in transit. We limit submissions to five per IP address per hour to stop automated abuse; that counter lives in memory and is discarded when the server restarts.

We do not sell, rent or share your address. If you want it removed, reply to any message from us or use the contact route on How we work, and it will be deleted from the mailbox.

Analytics

The site runs Google Analytics 4. It records the ordinary things — which pages are opened, roughly where in the world the reader is, what kind of device and browser, and which site referred them. Google sets cookies to do this.

We also record one custom event. When you click a link that leaves this site, we log the destination URL, the page you clicked from, which component the link sat in, and the affiliate tag on the link if it carries one. This is how we tell which recommendations people actually follow.

That event is about the link, not about you: it carries no name, no email address and no account identifier, and it is not joined to anything you may have submitted through the newsletter form. Browser-level tracking protection and Google's own opt-out add-on both stop it.

Affiliate links

Some outbound links to retailers and brands are affiliate links. If you buy through one, we may earn a commission at no additional cost to you. We participate in the Amazon Associates programme and in brand partner programmes run through affiliate networks including Awin.

Following one of those links hands you to the retailer, who then applies their own cookies and their own privacy policy. We never see your order, your payment details or your address — only, eventually, an aggregate count of sales attributed to us.

A commission does not buy a recommendation. What that means in practice is set out on How we work.

Hosting

The site is hosted by Vercel, which keeps standard server logs — IP address, time, the page requested, and the browser's user-agent string. These are operational records kept to run and secure the site.

What we do not do

  • We do not sell or rent personal information.
  • We do not run advertising networks or retargeting pixels on this site.
  • We do not have user accounts, so there is nothing to log into and no profile to build.
  • We do not knowingly collect anything from children under 13.

Your choices

You can ask us what we hold about you, and you can ask us to delete it. Given the above, the answer is usually short: either an email address in a mailbox, or nothing at all. Reach us through How we work and we will act on it.

If this page changes, the date at the top changes with it.