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Playbook · 02 · GA4 + GTM

How I rebuild broken analytics.

Most analytics rebuilds aren't a tooling problem — they're a documentation problem. The fastest path back to trust is writing down what should be measured, then making the tags reflect the doc.

1 spec
One source of truth
Applies to
Sites with broken, doubled, or stuck-on-GA3 tracking
Engagement
3–4 week rebuild
Framework
1 spec
Status
Open · 2026
01 · Where this engagement starts

Three dashboards.
Three answers.

A migration was done in a sprint. Tags fire twice. Conversions count on the wrong step. The marketing dashboard, the finance dashboard, and the GA4 explore all give different numbers — and nobody knows which one is right.

The team stops shipping decisions off data, because every decision needs a 20-minute "can we double-check this number?" conversation. That's the symptom I get called for.

02 · How I work it

Rebuild the data layer.
Then the tags.

I start with the spec, not the tool. Every event the business needs, named in plain English. Every parameter typed. Every conversion mapped to a single defined step. Marketing and finance review the spec *together* before a single tag changes — the goal is one document everyone signs off on.

Then the GTM rebuild — versioned containers, paired QA, a documented publish cadence. Three weeks in there's a clean GA4 property, documented events, and a dashboard the team agrees to.

The iterations

  • Week 1. Audit existing tracking. Catalog every gap, doubled fire, and broken conversion. Write the data layer spec the team wishes existed.
  • Week 2. Rebuild GTM container against the spec. Paired QA between me and a stakeholder. No publishing yet — staging only.
  • Week 3 — 4. Publish in waves. Watch live data against expected. Hand off the spec, the container, and a maintenance doc.
03 · What you get

Tracking that holds.
Without me.

Three artifacts ship with the engagement: a written data-layer spec, a versioned GTM container, and a maintenance doc your team can use after I leave. Plus a handoff session walking through what changed and why.

The point is not that I built it. The point is that the team can edit it.

Data-layer spec
1 doc
team-reviewed
GTM container
Versioned
with paired QA
Maintenance doc
1 doc
for the team after I leave
If this playbook fits

I take engagements
like this
one at a time.