Funnel observability with zero front-end code: reusing the GTM data layer (latest dynatrace)

[AurelienGravier]

Hi, 

I'd appreciate your help / feedback on a specific use case.

Client context. An e-commerce company already has a data layer rich in business data, orchestrated by Google Tag Manager. This data layer currently feeds their analytics solution (Piano Analytics): GTM listens to data layer events (product view, add to cart, checkout steps, purchase) and, on those triggers, fires a tag that forwards the data to Piano.

Objective. Track the conversion funnel in Dynatrace (conversion rate, drop-off by step, journey analysis) by reusing the exact same business data, with no new front-end development and without restructuring the existing data layer (a firm constraint set by the client).

Proposed mechanism. Replicate for Dynatrace what GTM already does for Piano: add a Dynatrace Custom HTML tag in the GTM container as a "sibling" of the Piano tag, wired to the same triggers and reading the same variables. At each funnel step, GTM would fire Piano and, in parallel, a dtrum.sendBizEvent(type, attributes) call via the RUM JS. The RUM JS is already injected before GTM (so dtrum is available when the tags fire), and RUM business events are already enabled on the tenant.

Key advantages.

• No duplication of an existing data foundation: we reuse the business data already present in the data layer as-is, rather than building and maintaining a second data structure.
• No front-end development required: the business/analytics teams already own and operate the GTM tags autonomously, so the integration ships through GTM without depending on a front-end dev backlog or release cycle.
  
  

Feasibility question. Is it a sound and supported approach to drive sendBizEvent from a GTM tag (Custom HTML) rather than from the application code, mirroring the exact GTM > Piano integration pattern?

Thanks in advance, Aurélien.