Spectare runs on Spectare. The site you are reading is a customer of the product it sells, and the sections that vary on it are filled the same way they would be filled on your site.
You can test it. Open this page in a fresh browser session after following a campaign link with a UTM parameter, and the sections will shift to reflect that signal. Come back the next day from a direct visit and the selection changes again, because the visit history that informs it lives in your browser and the signal pattern is different. What you cannot see is a change within the same session, because Spectare is deliberate about this: it classifies once per session so the page does not rearrange itself under a visitor who is still reading.
The sections that vary sit inside defined zones. The content inside each zone is chosen by the same assembly engine, the same atom library, and the same classification logic that your workspace would use. Nothing is mocked up for demonstration.
If you want to see the reasoning behind a specific section, add ?xray=1 to any URL on this site. The overlay will show you which atom was selected, which audience and funnel stage it was written for, and why it was placed where it was.
This is one atom from the Spectare content library. Spectare assembles the right atoms for each visitor in real time, based on who they are and how they arrived.