This pattern is part of "Patterns of Legacy Displacement"

Revert to Source

Identify the originating source of data and integrate to that

This page is a stub. We intend to fully expand it in later revisions of this material. However we are still in the middle of developing these patterns, so it's likely that patterns will be renamed, split, or merged as we continue to learn how best to frame and explain these ideas.

Many large legacy systems can be become the perceived single source of truth for key business data, thus in turn becoming a 'must have' integration point for any new solution. By taking the time to trace the source of data we can sometimes simplify the integration needed and avoid connecting to the existing legacy estate, we connect to the originating source instead.

It is also often vital to understand the true sources of data for business and legal reasons such as GDPR. We have seen many examples where people view the legacy systems as the originator of the data because the true sources have become obscured or even 'lost'. It is only when a failure or issues arise that the true source becomes clear.