Modernize without losing the business rules nobody documented
Years of changes are encoded across old services, database behavior, UI screens and operational exceptions. A rewrite that preserves the happy path can still lose the rules customers rely on.
Example: move invoices from a monolith to a service
Before development, understand which statuses and customer actions depend on invoices, what integrations listen to events, which exceptions finance handles manually, and what is only implemented in the old UI. During migration, compare the source behavior to the target implementation. After release, show changed business behavior visually.
Illustrative example — not a customer project
Change: Move invoices from a monolith to a service
- Invoice service — new
- Invoice statuses — one has no match in the target
- Finance exception and the old UI rule — missing from the target
- Integrations and customer actions — affected
- Outside the deployment — coverage unknown
What the migration team sees
- Mismatched status
- One invoice status in the monolith has no equivalent in the target service.
- Missing rules
- A manual finance exception and a rule implemented only in the old UI are not in the target yet.
- Affected customer actions
- Paying, downloading and disputing an invoice read the new service.
- Unknown coverage
- Systems outside the connected repositories are marked unknown, not assumed safe.
Visual inspection complements code checks and regression testing; it does not prove every untouched screen is correct.
Outcomes
Better migration estimates; fewer undiscovered regressions; faster onboarding for modernization teams; review of preserved behavior rather than only data migration scripts.
Pilot scorecard
- Critical flows represented
- Rules preserved in the test suite
- Uncovered dependencies
- Migration defects
- Scope accuracy
- Elapsed time to acceptance
Products in this workflow
- Intelligence
- Enterprise — if private
- Vibe
- Business Review
- GMM Local — if required