Across to the shop

The organiser's site and the Eventix shop are on different domains, so a cookie cannot follow the visitor. The SDK carries the anonymous id in the link instead:

1. Links to the configured shop domains (shop_domains in the configuration) get a _evx=<id>.<timestamp> parameter when the visitor clicks them.
2. The SDK on the shop removes it from the address bar and adopts the id, if the link was younger than link_max_age_seconds (two minutes by default) when the page loaded.
3. The shop's calls carry that anonymous id, and so does the order when the shop reports it, so the order joins the sessions on the site without identity resolution.

The shop sends the basket activities as the visitor shops: started_basket on the first item, added_to_basket and removed_from_basket per item, entered_details when the buyer fills in their address (banner-exempt: it carries its own identifier), and placed_basket just before the payment redirect, which links the browser to the order id and is banner-exempt too. The order itself arrives later from the ticketing system, with the same order_id and the same anonymous id in its tracking info. A basket that never reaches placed_basket is what an abandoned-basket journey looks for.

Nothing proves the browser's link to that order beyond the id it carried; it is an association, not identity evidence.