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Case study

Replacing a loan management system
under a live deadline

Domain

Loan management

Role

End-to-end delivery

Timeline

~3 months

The situation

A membership organisation with 10,000 members was preparing to launch financing agreements for a new product line. The plan was to integrate with their existing operational lease partner's loan management system, giving members live status updates through the organisation's own app.

During the integration work, it became clear that the partner's legacy system couldn't support the data flows or the level of transparency the product required. The integration wasn't just difficult — it was architecturally incompatible with the member experience they needed to deliver.

The decision

Rather than compromising the product around the limitations of a legacy system, the team made the call to build a replacement. Not a full loan management platform — but the specific capabilities the business actually needed: interest calculations, payment plan generation, refinancing logic, and agreement document generation.

For the parts that didn't need to be custom — ledger accounting and invoicing — they integrated with an existing ERP system. Build what matters, reuse what works.

CUSTOM-BUILTAgreementSigningLoanCalculationsRefinancingLogicDocumentGenerationEXISTING ERPLedgerAccountingInvoicingReporting & Reconciliation

Build what matters, reuse what works.

Why this path

Building a replacement sounds risky. But the alternative — wrapping a legacy system in workarounds — would have created a fragile foundation for a product that needed to scale. The real risk was in staying.

The team started with the most critical path: the ability to generate and sign financing agreements. That went live first. From there, they built forward along the process — always ensuring the next step in the member journey was working before it was needed. Each piece proven in production before the next was built.

Delivery sequence

Week 1–4

Agreement signing

Generate and sign financing agreements. Live in production.

Month 2

Loan calculations

Interest, payment plans, refinancing logic — the custom core.

Month 2–3

ERP integration

Ledger accounting and invoicing via existing ERP. Reuse what works.

Ongoing

Member experience

Live status, transparency, self-service — built on proven foundations.

What was avoided

By choosing to build the custom core and reuse everything else, the team avoided months of integration workarounds against a system that couldn't deliver what the product needed. Members got a transparent, real-time experience from day one — not a compromised version stitched together around legacy constraints.

Domain understanding made this decision possible. Knowing which parts of a loan management process are genuinely complex (interest calculations, refinancing logic, regulatory document requirements) and which parts can be delegated to existing systems (ledger, invoicing) is what allows you to make a call like this with confidence.