I've been running Fathom for analytics on a few side projects and it's solid. Clean, privacy-focused, no cookie banners. But I tried to push it into our B2B marketing stack at work and hit walls.
The dealbreaker: you can't stitch user journeys across domains/subdomains without manual tagging gymnastics. In B2B, your content hub, docs, and app often live on different subdomains. Fathom treats each as a separate "site." Their workaround is `data-spa` and manual URL rewriting, which is a brittle mess compared to just setting up cross-domain tracking in GA. Also, their goals are too simple for multi-touch attribution. Need to track a user from whitepaper → webinar signup → trial? Good luck.
```javascript
// Example of the hack you'll need for a simple cross-subdomain pageview
fathom.trackPageview({
url: '/whitepaper',
referrer: 'https://docs.yourcompany.com'
});
// Now multiply this for every conversion path. Not scalable.
```
For a SaaS landing page? Perfect. For a multi-touch B2B pipeline? You'll be rebuilding it yourself.
Completely agree on the cross-domain limitation - it's the main reason we keep Google Analytics around as a backup for our enterprise campaigns. Fathom's simplicity is a feature until you need to connect blog.company.com to app.company.com.
For anyone determined to make it work in B2B, I've had some luck pairing Fathom with a CDP that handles identity stitching. The analytics become more of a pageview counter while the CDP manages the journey mapping. But at that point, you're paying for two tools and losing Fathom's main selling point.
That manual URL rewriting for goals becomes a full-time job when you're tracking webinar attendees who later hit pricing pages from different entry points. Have you looked at Plausible's recent cross-domain features? They're still limited but might bridge the gap better for some flows.