Legacy Modernization for Insurance and Financial Services
The question isn't whether to modernize. It's how to do it without destroying the business value embedded in systems that — despite their age — still process millions of transactions reliably.
Legacy modernization in insurance and financial services is different. Your core systems aren't just old technology. They encode decades of business rules, regulatory logic, and operational knowledge that nobody fully documented. Rip-and-replace sounds clean. In practice, it's where modernization programmes go to die.
I'm Abdul Baruwa, founder of kaano.io. I've spent 25+ years modernizing exactly these systems. Currently, I manage CHAPS and BACS payment operations at a UK financial institution — systems where "legacy" and "critical" are the same word. I'm also CPO and CTO for insurance technology products, where I've taken monolithic .NET systems and rebuilt them as event-driven, CQRS architectures without stopping the business.
Why Legacy Modernization Fails
The Big-Bang Rewrite Trap
Someone sells the board on a complete replacement. Two years and several million pounds later, the new system handles 60% of what the old one did, the project is over budget, and the legacy system is still running in parallel — now with even less investment.
Underestimating Embedded Business Logic
A policy administration system that's been running for 15 years doesn't just "process policies." It contains thousands of business rules — some documented, most not — that handle edge cases, regulatory requirements, and market-specific logic.
Ignoring the Data Problem
Legacy systems hold historical data in formats that don't map cleanly to modern schemas. Data migration is consistently the most underestimated workstream. It's not an ETL job. It's an archaeological excavation.
Technology-First Thinking
"We need to move to microservices" or "We need to get off .NET Framework" — these are technology decisions masquerading as strategy. The right question is: what does the business need these systems to do that they currently can't?
Our Approach
Phase 1: System Archaeology (2–4 weeks)
Before touching code, I map what you actually have. Not just the technology stack — the business logic, data flows, integration points, and operational dependencies. I talk to the people who run these systems, because the most important documentation lives in their heads.
Phase 2: Modernization Strategy (3–6 weeks)
Based on the system reality map, I design a modernization approach. Strangler fig, domain-driven decomposition, event-driven decoupling, or targeted .NET Framework to .NET migration. Usually a combination. Sequenced to deliver business value incrementally — not a two-year plan that delivers nothing until month 23.
Phase 3: Delivery & Architecture Governance (ongoing)
I work with your engineering teams during delivery. Architecture reviews. Code quality oversight. Pattern enforcement. The goal is to transfer capability, not create dependency.
Who This Is For
- Insurance carriers and MGAs running policy admin, claims, or underwriting systems on aging technology stacks that limit product innovation
- UK financial institutions with core banking or payment systems on .NET Framework, mainframe, or other legacy platforms approaching end-of-support
- CTOs and Engineering Directors who've been burned by a failed modernization attempt and need a different approach
- Operations leaders who know their legacy systems are a resilience risk but can't get budget without a credible plan
- PE-backed insurance and fintech firms where legacy technology is suppressing valuation or blocking growth initiatives
What You Get
| Deliverable | Detail |
|---|---|
| System reality map | Comprehensive analysis of current-state systems — business logic, data flows, integration points, technical debt, and operational dependencies |
| Modernization strategy | Architecture target state with pattern selection (strangler fig, CQRS/ES, domain decomposition), sequenced by business value and risk |
| .NET migration plan | Specific to .NET Framework → .NET migration: dependency analysis, breaking changes, architectural improvements, and phased delivery plan |
| Data migration approach | Schema mapping, transformation logic, validation strategy, and rollback plan for historical data |
| Business case | ROI model linking modernization investment to specific business outcomes — speed to market, cost reduction, resilience, compliance |
| Architecture governance | Ongoing code review, pattern enforcement, and capability transfer during delivery |
The Work Behind the Words
I've modernized insurance core systems — underwriting, claims, policy administration — moving them from monolithic architectures to event-driven systems built on CQRS and event sourcing. I've migrated .NET Framework applications to modern .NET in regulated environments where downtime means regulatory reporting.
Currently, I manage payment systems that are the definition of "legacy and critical." I understand the tension between "this needs to change" and "this cannot break."
If your modernization challenge lives at that intersection, we should talk.