You see 100 sales in Stripe. In GA4 — 60. In Facebook Ads — 40. Which number do you believe? The Stripe number is right. The others are not. And the gap is getting wider every year. When I audited analytics on Pikkuna — a Finnish e-commerce platform serving 35 countries — the client-side tracking was missing roughly 35–40% of purchase events. Not because the code was wrong, but because the events were blocked before they ever left the browser. iOS users, Firefox users, anyone with an adblocker — their conversions were invisible to GA4 and Meta. The fix is moving tracking to the server. When the event fires from your backend, there is no browser, no extension, no ITP to intercept it. Here's exactly how I implemented it in Next.js. Why Client-Side Tracking Is Dying The degradation has been gradual enough that most teams haven't noticed how bad it's gotten. iOS 14.5+ App Tracking Transparency (ATT). Apple now requires explicit opt-in for cross-app tracking.…