Should you integrate or replace your business systems?

1. Locate the limitation

Map where information originates, where it is copied and where the business waits. Identify the authoritative system for each important record. Ask whether the missing capability is already available but unused, or whether the current system genuinely cannot support the process.

Review interfaces, supported versions, vendor restrictions and the skills available to maintain the system. Keep business frustration and technical risk visible, but do not assume they have the same cause.

2. Compare four options

Evaluate each option against the required business outcome, disruption, dependencies and ongoing operating cost. Document evidence and unresolved assumptions.

• Configure when an existing supported feature can meet the need.
• Integrate when the applications still fit but their data or workflows do not connect.
• Modernize incrementally when you can isolate a limiting capability and replace it in stages.
• Replace when critical requirements, supportability or constraints cannot be addressed sustainably through smaller changes.

3. Treat migration as part of the solution

Plan identifiers, data mapping, reconciliation, permissions and responsibility for failed transfers. Agree which system owns a record while both are running. Test recovery and rollback boundaries before moving operational work.

Incremental replacement can keep unmigrated capabilities in the old system while new ones take over. Microsoft describes this as the Strangler Fig pattern. It requires suitable boundaries and routing; it does not remove the need to manage dependencies and data consistency.

Microsoft: Strangler Fig pattern

4. Record what would change the decision

A useful architecture review produces alternatives, trade-offs and a recommendation with assumptions. Include licensing, integration maintenance, training, migration effort and the cost of running systems in parallel—not just the build estimate.

Define the next evidence-gathering step. An interface test or a review of real data may resolve the uncertainty before a larger commitment. Name an owner for the transition and agree how the business will accept the result.

A related project

Defiro Health’s published project connects patient applications, a clinical platform and devices. It provides a real integration example, not proof that replacing an existing system is right for your organization.