Modernise the system without losing the business logic

Find the real dependencies

Document interfaces, scheduled work, reports and manual adjustments as well as the main application. Important behavior may live in spreadsheets or in one person’s routine. These dependencies affect the order in which a system can be changed.

Choose a manageable boundary

A staged replacement can isolate a workflow or interface before a larger migration. Define how old and new components exchange information and which system owns each record during transition. Avoid ambiguous periods with two masters.

Reconcile before acceptance

Compare records, totals and exceptions using rules the business understands. Exercise failed transfers and corrected transactions. A successful import command is not evidence that the migrated system preserves the business meaning of the data.

Plan the operating handover

Provide runbooks, known limitations, escalation and recovery instructions. Train the team on real scenarios and confirm who owns each integration. Modernisation is complete when the business can operate the replacement, not only when the new interface is deployed.

Common questions