Marketing metrics answer the demand question: how do people find the product, what does it cost to bring them in, and are they worth more than they cost? SEO is the part of that question a frontend team is genuinely on the hook for — a chunk of it is frontend work — so it makes a natural bridge from performance metrics to growth ones. Here's the set, from the markup you own to the economics of a customer.
Product metrics answer a different question from "is the frontend fast?" — they ask whether the product delivers value: do people show up, do they reach the aha moment, do they come back, and do they stick around. Almost all of it is measured in the browser by frontend event tracking, but the numbers describe the product, not the frontend's health. Here's the set that actually changes decisions.
Picking a product analytics tool in 2026 means choosing between a dozen mature options that all claim to do the same thing. This is a developer's field guide to how Google Analytics 4 (GA4), PostHog, Mixpanel, Amplitude, Heap, Pendo, Statsig and the rest actually differ — on data model, instrumentation, self-hosting, and price.
I wanted to know which posts people actually read — without dropping a tracking cookie on someone the moment they land. This is how the blog runs Google Analytics 4 (GA4) on a static Docusaurus site while keeping it completely off until you opt in.