Cookieless EC measurement: a 4-step shift to first-party

"Safari traffic looks like it lost 30% of conversions year over year." "Tags fire empty after the cookie banner went up." I keep hearing variations of this from EC operators — and most of the time, the cause isn't the site or the campaigns. Browsers and regulators are dismantling the third-party cookie premise at the same time , and the measurement stack many EC teams rely on is built right on top of that premise. Below is the short version of how I think about migrating to first-party measureme