SDK Overview
The Signal Sparrow SDK is the small piece of code you added to your website in Install the SDK. This page explains what it does and why it's built the way it is.
What makes it different
Most tracking tools use a third-party pixel — a script that loads from someone else's domain (like facebook.com). Browsers and ad blockers increasingly block those, so a big chunk of your visits simply go missing.
Signal Sparrow works differently:
- First-party. The SDK loads from your own domain, so browsers treat it as part of your site — not as an outside tracker. Far fewer visits are lost.
- Server-side friendly. The important work happens on Signal Sparrow's servers, not fragile browser code, so your data stays accurate even when a visitor closes the tab quickly.
- Cookieless-friendly. It still works when third-party cookies are blocked. It uses a single first-party value to remember a visitor (more on that in Consent & Privacy Modes).
More of your real traffic gets measured, which means a higher match rate and a more complete picture of which ads actually bring paying customers.
What it captures automatically
Once installed, the SDK quietly records the useful signals on every visit — you don't have to do anything:
- The page being viewed and where the visitor came from (the referrer).
- Ad click IDs and UTM tags in the link they arrived on — see Click IDs & UTMs.
- Basic, non-personal context like coarse device type and timestamps.
What you add yourself
There's really only one thing to add by hand: telling Signal Sparrow who a visitor is once they identify themselves (usually at signup or login). That single step is what connects an anonymous visit to a real paying customer.
Choosing an SDK
| Your website | Use |
|---|---|
| No-code / CMS / plain HTML | The HTML snippet |
| React, Vue, or other JavaScript apps | The Web SDK (@signalsparrow/sdk) |
| Next.js | The Next.js SDK (@signalsparrow/next) |
All three do the same job — pick whichever matches how your site is built.