What this site
knows about you.
This is my personal site. I measure it so I know what people read and where they get stuck. Below is all of it: what is collected, who sees it, how long it's kept, and how to turn it off.
Last updated October 12, 2026
Your switch
Analytics, session recording and Google Analytics are on for this browser.
The choice is saved in this browser only (a localStorage entry), so it applies per browser and
device, and clearing site data resets it.
01 · Visits
When a page loads, the site sends a small record to my own server (it runs on Cloudflare). The record contains:
- the page, and the site or campaign link that brought you here;
- your country and city, worked out by Cloudflare from the connection;
- device type, browser, operating system and screen width;
- a random visitor ID stored in your browser and a random ID for the current tab. They are not tied to your name or email.
It also notes a few actions: a link you follow off the site, an email link, playing or pausing the music, a search pick, and the name of a terminal command you run. Anything else you type in the terminal stays in your browser.
Your IP address is not stored. These records are kept until I delete them.
02 · Session recordings
The site records how a visit plays out: what was on screen, scrolling, mouse movement and clicks. I watch some of these to find what's confusing or broken. Nobody else has access.
- Anything typed into a field is masked in your browser before it is sent. Keystrokes never leave it.
- If your browser sends Do Not Track or Global Privacy Control, nothing is recorded.
- Recordings are deleted after 60 days.
03 · Google Analytics
The site also uses Google Analytics. It sets its own cookies (_ga) and sends Google the page,
your browser details and your IP address, which Google uses to estimate location. Google handles that data
under its own privacy policy.
The switch above turns it off on this site, and Google's
opt-out add-on turns
it off everywhere.
04 · The updates email
If you subscribe, I keep:
- your email address;
- when you signed up, the page and form you used, the site that sent you, and your country;
- your IP address, used only to limit how many signups one network can send in an hour.
Nothing is sent until you click the confirmation link. The emails come from my own server, not a mailing service. They count opens and link clicks in total, never per person. Every email has an unsubscribe link, and if you want your record deleted entirely, email me.
05 · Stored in your browser
Besides the IDs above, the site remembers the music track and position, and which view you picked on /how-i-build. That stays in your browser and isn't sent anywhere.
06 · Who else sees it
Cloudflare hosts the site. Like any host, it handles your connection, including your IP address, to deliver pages. Google receives the Google Analytics data described above. That's the whole list. There are no ads or ad trackers, and nothing is sold or shared.
07 · Questions or deletion
Email kalvin at mizzi dot com to ask what I have from your browser or
address, or to have it deleted. For browser data, include your visitor ID so I can find it:
(none yet).