Specsavers is a global optical and audiology retailer with a complex data ecosystem including a sophisticated Google Analytics 4 (GA4) implementation, spanning multiple markets. As the company continues its digital transformation, the ability to manage data efficiently and consistently across geographies is critical to driving performance, delivering insight at speed, and reducing costs.  

To solve these challenges, Specsavers partnered with Merkle to implement a cutting-edge GA4 automation and transformation framework using Dataform, unlocking a new level of efficiency, governance, and insight scalability. This bespoke solution allows local market teams to maintain autonomy while benefiting from global data consistency, supporting faster reporting, deeper customer insight, and more informed decision-making. 

With cost reduction, and enterprise-grade governance built in, this solution sets a new benchmark for data engineering in the retail and healthcare sectors.

With each Specsavers market operating its own GA4 property, the business faced increasing complexity in managing data at scale. Every market had its own regional tracking nuances, making centralised reporting and analysis difficult to standardise.

Rolling out changes, integrating new custom fields, and reconciling online and offline journeys became time-consuming and error-prone.

This fragmented data environment led to:

• Inefficiencies in launching new markets or updating reporting frameworks. 

• High costs from users querying raw GA4 data in BigQuery.

• Inconsistent data models across geographies.

• Difficulty combining online and offline touchpoints for a complete customer view.

Manual updates weren’t sustainable for a global business with evolving needs. Specsavers needed a scalable, automated solution to keep pace with change and ensure accurate, governed data pipelines across all markets. 

Merkle deployed a best-in-class implementation of Dataform, tailored to Specsavers’ global architecture and needs. The solution automates schema generation for each market, enabling rapid onboarding, scalable maintenance, and intelligent governance.

Key innovations included:

• Automated bronze layer: A script dynamically creates and evolves the bronze layer of transformed data, removing manual intervention when new GA4 custom parameters are introduced.

• Field- and row-level governance checks: Proactive error detection and alerting prevent bad data from flowing into downstream systems.

• CI/CD development: Integration with GitHub allowed version control and continuous deployment across BigQuery pipelines, ensuring consistency and traceability.

• Online–offline journey alignment: Offline customer identifiers were extracted into online datasets, helping unite the end-to-end experience, from booking and appointment to purchase and aftercare.

This approach is unique in the market. None of Merkle’s 100+ clients had implemented GA4 automation at this scale or with this level of customisation.