Insurance ESB rationalization
Client
A Dutch insurance group, multi-brand life and pensions carrier, operating across the long-standing core insurance product lines and a substantial in-force policy base.
The group ran policy administration, claims, payments, and distributor integration across an estate that had accumulated over more than a decade of acquisitions, product launches, and regulatory cycles. A single vendor enterprise service bus (ESB) had grown to absorb most of the integration load — and most of the integration risk. By engagement start, the platform was carrying integration flows in the hundreds, with mixed ownership and inconsistent design.
The problem
By the time Lemraj was engaged, the ESB was carrying more cost and more risk than business value. Specifically: a high volume of integration flows with mixed ownership and inconsistent design; a growing operational and licensing footprint disproportionate to the work the platform was actually doing; technical risk concentrated on a vendor product with limited specialist availability; and resistance to modernization elsewhere in the estate, because every adjacent application change had to navigate the ESB to land safely.
Leadership wanted a credible plan to rationalize the integration estate — decommission what was no longer earning its keep, replace what was, and reduce concentrated risk on the legacy platform without freezing the policy-administration platform that the rest of the business depends on.
What we did
Lemraj engaged across architectural assessment and rationalization delivery. The work split into three connected streams:
Assessment. A structured inventory of integration flows — ownership, business value, operational cost, and risk exposure — built so that decisions could be made at the flow level rather than at the platform level.
Target architecture. A target state designed to reduce the integration footprint to a smaller, observable layer aligned to the carrier's policy-administration platform. Each surviving flow had an explicit owner, contract, and operational pathway.
Rationalization delivery. Phased decommissioning and replacement, with each flow treated as a separate unit of work — assessed, decided, migrated or retired, and verified independently. Replacement integrations were built alongside the in-house engineering team, with operational design (observability, contract testing, decommissioning verification) treated as part of the delivery, not as a follow-up.
Outcome
The engagement produced a documented target integration architecture and a rationalization plan owned by the client, decommissioning of selected legacy integration flows with a defined path for the remainder, a reduced operational and licensing footprint on the legacy ESB platform, and an in-house engineering team able to operate the new integration layer without specialist external dependency.
Specific scale and complexity outcomes — flow counts, operational risk reductions, licensing footprint changes — are subject to client confidentiality and available on request.
Stack and approach
- Pattern: Phased rationalization. Decommission, replace, or retire each flow as a separate unit of work.
- Languages and platforms: .NET, with replacement integration built on lightweight, observable patterns aligned to the carrier's policy-administration platform.
- Cloud / hosting: A mixed estate, with the target integration layer designed for portability between on-premises and Azure rather than coupled to either.
- Operational design: Observability and contract testing designed as first-class deliverables.
Engagement model
- Duration: Multi-phase engagement spanning multiple delivery cycles.
- Team shape: Lead architect plus senior associates engaged for specific delivery phases. No junior pyramid.
- Contracting: Time and materials with defined scope per phase, milestone reviews, and a written off-ramp at the end of each phase.
- Working model: Embedded with the in-house engineering team and adjacent platform owners. Insurance-sector compliance and change-control constraints respected throughout.