We assess your legacy systems and lay out an incremental modernisation plan that reduces risk and keeps the business running throughout the transition. Data is migrated safely and critical functions are rebuilt on modern, supported, secure technologies. The service frees you from the high maintenance burden and security risks of end-of-life technology.
What's included
- A full technical assessment of the existing system: architecture, dependencies, code quality, security risks, and end-of-life technology.
- An incremental modernisation plan using the strangler-fig pattern, replacing functions one module at a time without a full shutdown.
- Replatforming or rebuilding on a modern, supported platform according to the case for each component.
- Safe data migration with cleansing, integrity checks, and reconciliation before and after cutover.
- A temporary integration layer that keeps the legacy and new systems running side by side during the transition.
- Risk-managed cutover with a clear rollback plan and considered release windows.
Methodology & standards
Assessment and dependency mapping: we analyse the existing system and classify functions by risk, value, and technical feasibility.
Transition planning: we set the order of module replacement, the right modernisation pattern per component, and the data-migration strategy.
Incremental build and parallel integration: we rebuild critical functions first and run them alongside the legacy system through an integration layer.
Data migration and verification: we move data in batches with reconciliation and equivalence testing between the two systems.
Managed cutover and safe decommissioning: we execute cutover within a planned window with a rollback plan, then retire legacy components gradually.
Deliverables
- An assessment report of the existing system with a risk register and dependency map.
- A documented incremental modernisation plan with module ordering and transition patterns.
- The modernised system on a modern, supported platform with its rebuilt functions.
- A data-migration report and the results of reconciliation and equivalence tests.
- The cutover plan, rollback plan, and a launch execution log.
- Documentation of the new architecture and source code, with a maintenance plan.
Regulatory controls it satisfies
Typical timeline
The modernisation schedule depends on the size of the existing system and its module count; it usually begins with a two-to-four-week assessment, followed by an incremental transition planned in quarterly or shorter waves to keep risk low.
Common questions
Will our business stop during modernisation?
No. We follow an incremental approach that keeps the legacy system running in parallel with the new one through an integration layer, replacing functions one at a time within considered windows, with a rollback plan for every cutover step so operations are not disrupted.
How do you guarantee our data stays intact during migration?
We cleanse and migrate data in batches and run reconciliation and equivalence tests between the two systems to confirm results match before final sign-off, keeping the legacy system as a reference copy until verification is complete.
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