Data model, database and infrastructure, today and after the multi-tenancy line moves

Scene 9: The deep layers today

Below the domain primitives are the data model, the database and the infrastructure. Every customer stands on them. Where a customer needs data the model did not include, platforms offer custom fields, stored as metadata so that the shared schema itself does not change. In our experience, these often hold information at the edge of the domain rather than at its core. Risk grows with depth. A change here cannot easily be seen, compared with what came before, or reversed. Because the revenue depends on these layers, they change last, if at all.

Scene 22: the deep layers

At the bottom of the stack, the deep layers stay where they are. Few customers' needs reach the deep layers, and those that do carry the most risk. In a brownfield product, the data model, the database and the infrastructure stay shared and unchanged, and an agent working in the language cannot reach them. The needs that do reach this far are handled case by case, and the site sets out how. Where a company already plans to rebuild the layer that applies configuration, that rebuild is the place to design the lower line in, and there the greenfield path begins.