Server-side tag managers most commonly Google Tag Manager's server container (sGTM) proxy tracking requests through your own subdomain rather than running JavaScript directly in the visitor's browser. The result: better data quality, fewer ad blocker losses, and a single governed layer where you control what fires and when.

This guide shows you how to integrate Castlytics with a server-side tag manager setup so that your page views, conversion events, and promo code data flow through your server container instead of relying entirely on the client-side snippet.

How Castlytics Tracking Works (Quick Recap)

We built Castlytics to solve a problem we kept hearing from brands: podcast and creator campaigns are expensive, but almost impossible to measure properly. Tracking links help, but they miss everyone who types the URL manually. Promo codes help, but they don't capture the full picture. Post-purchase surveys fill in some gaps, but analysing them is manual work.

For a single brand running a handful of campaigns, that was already a meaningful problem. For agencies managing creator campaigns across five, ten, or twenty clients simultaneously, it was a different level of painful.

Today we're announcing that Castlytics is now built for agencies too.

Third-party cookies have been deprecated or blocked in Safari and Firefox for years. Chrome's phase-out is ongoing. The advertising industry has spent years panicking about what this means for attribution.

For podcast advertisers, the news is mostly good: the best podcast attribution methods were never dependent on third-party cookies in the first place.

Here's how cookie-free podcast attribution works.