NAXT PERSPECTIVES · Product Engineering
Map before replacing
Understand the processes, dependencies, and data flows inside a legacy application. Some complexity represents valuable business knowledge. Separate that knowledge from the implementation constraints you want to remove.
Choose a useful boundary
Start with a workflow whose dependencies can be understood and tested. Define what the new component owns, how it communicates with existing systems, and how users will transition between the two.
Reconcile the data
Migration is a business validation exercise as well as an engineering task. Agree on reconciliation rules, test representative edge cases, and make discrepancies visible to the people who understand the records.
Plan the operating transition
A successful release includes monitoring, runbooks, access controls, support ownership, and a recovery plan. Retire old components only after the replacement is working reliably and its dependencies have moved.