Member-organisation Azure integration modernization

Client

A national membership organisation operating at scale across the Netherlands, with a member base measured in the millions. The organisation runs member administration, contribution and payment processing, case management, and adjacent member services on a multi-decade systems estate.

The integration layer between member, payment, and case-management systems had been built up over years of point-to-point connections, vendor middleware, and adjacent platform additions. By the time Lemraj engaged, the on-premises middleware platform had become a maintenance liability rather than an operational asset, and new member-facing service delivery was being slowed by the cost of touching it.

The problem

Three constraints shaped the engagement:

The organisation needed to keep delivering new member services without freezing existing ones during the transition. The in-house engineering team was finite, and ownership of the target architecture had to stay in-house — not transfer to a vendor. And the legacy middleware platform could not be replaced in a single cutover without unacceptable operational risk to live services.

Leadership wanted a credible migration path to a modern, observable, Azure-native integration architecture that could be moved to one integration at a time, with parallel-run validation and a defined rollback path at every step.

What we did

The engagement ran in three phases over multiple delivery cycles. The full migration scope spanned tens of distinct integration paths across member, contribution, payment, and case-management systems.

Phase one — assessment and target architecture. A topology and failure-mode assessment of the existing integration estate, followed by a target architecture built on Azure-native services. Event-driven where it earned its keep; request/response where it did not; orchestrated workflows reserved for processes that genuinely spanned multiple systems.

Phase two — pilot migration and operational design. A first integration migrated end-to-end to the target architecture, with observability, dead-letter handling, replay, and alerting designed as part of the integration rather than retrofitted. The pilot also served as the template — operational and architectural — for the migrations that followed.

Phase three — phased cutover. Subsequent integrations migrated one at a time, with parallel-run validation against the legacy platform and a defined rollback path for each cutover. Each migration was built in collaboration with the in-house engineering team, with knowledge transfer designed in from the start.

Outcome

A documented Azure-native integration architecture and migration plan, owned by the client. Selected integrations migrated from the legacy middleware to the new architecture, running in production with improved observability and operational control. A reduced operational dependency on the legacy middleware platform, with a defined decommissioning path for the remainder. An in-house engineering team capable of operating and extending the new architecture without ongoing Lemraj presence.

Specific scale, throughput, and operational outcomes are subject to client confidentiality and available on request.

Stack and approach

Cloud: Microsoft Azure as the target platform.
Integration patterns: Event-driven for asynchronous workflows; API-led for request/response; selective use of orchestrated workflows where business processes spanned multiple systems.
Languages and platforms: .NET, with infrastructure as code for the Azure platform components.
Operational design: Observability, dead-letter handling, and replay designed as first-class deliverables.
Migration model: Phased, integration-by-integration cutover with parallel-run validation.

Engagement model

Duration: Multi-phase engagement.
Team shape: Lead architect plus senior associates as required. Embedded working with the in-house engineering team.
Contracting: Time and materials with defined scope per phase and a written off-ramp at the end of each phase.
Working model: Senior-led delivery, with knowledge transfer to the in-house engineering team designed in from the start.