// tracking quality monitoring

Know when your tracking breaks — before your reports do.

Tracking Sentinel continuously validates your website events against an explicit contract. It works from privacy-safe metadata, so you get diagnostics without building a second copy of your customer data.

Request early accessSee how it works
shop.example — last 24h
page_view● valid12,480
view_item● valid4,902
add_to_cart● items[].price missing311
begin_checkout● valid148
purchase● not observed · 6h0
generate_lead● valid37

Stored: field names, types, counts, status. Not stored: IDs, amounts, product names, form contents.

// how it works

Three steps from “we think it works” to “we know it does.”

  1. 01

    Define the contract

    Describe the events you expect — GA4 defaults like page_view and purchase, plus your own custom events — with required parameters and types, in versioned YAML.

  2. 02

    Observe real page loads

    A lightweight GTM monitor records the shape of each event after the visitor gives consent: which fields were present, their types and item counts. Never the values.

  3. 03

    Validate and alert

    Every observation is checked against the contract. Missing events, drifting parameters and broken consent handling surface in the dashboard before they reach your reports.

// features

Built for analysts who are tired of finding out on Monday.

Event contracts

GA4-aligned default events are locked to the standard; custom events carry their own parameters. A misspelled page_location stays an error, not a new field.

Consent-gated monitoring

Nothing is sent before measurement consent. Withdraw consent and monitoring stops on the next page load.

Live and historical views

Live monitoring refreshes every 30 seconds; overall and per-client reporting covers any date range.

Per-client profiles

Keep contracts, allowlists and reporting separate for every site or client you manage.

Discovery of unknown events

Events that are not in the contract are captured as discoveries, so you can map or reject them deliberately.

Self-hostable

Runs as a small Docker Compose stack: FastAPI, PostgreSQL and a dashboard. Your infrastructure, your data.

For in-house teams

Catch a broken checkout event after a release, not after a month of missing revenue in GA4.

For agencies

Monitor every client's implementation from one place, with separate profiles and evidence to share.

// security & privacy

Designed to collect as little as possible.

  • Shapes, not values. Order IDs, amounts, product names, form contents and arbitrary dataLayer values are never persisted.
  • Consent first. The monitor only runs after measurement consent and respects withdrawal.
  • Separated surfaces. The public collector accepts only allowlisted observations; the dashboard and API sit behind access control.
  • Your infrastructure. Run it yourself, or in a dedicated pilot environment — observations are never shared across customers.

// early access

Join the pilot.

We are onboarding a small number of teams running GA4 and Google Tag Manager. Pilot participants get hands-on setup of their first contract and direct input on the roadmap.

Request early access

Or write to hello@trackingsentinel.com