Services / Legacy System Modernisation
Legacy System Modernisation
Refactoring and migrating ageing applications onto modern, cloud-native foundations. Better performance and less technical debt, without disrupting daily operations.
Best for: Businesses reliant on ageing, business-critical systems that have become too risky to update
Decades-old software often runs the entire business, which is exactly why replacing it feels impossible. We modernise your legacy applications incrementally — refactoring, re-platforming, and migrating piece by piece while the system remains fully operational. We replace fragile tribal knowledge with modern code and documentation, eliminating the risk of a disastrous big-bang switchover.
What's included
- Deep technical audit of the legacy system to identify real failure points and technical debt
- Phased, incremental migration plan utilising modern strangler-fig patterns
- Secure, validated data migration workflows running in parallel with the old system
- Comprehensive documentation mapping undocumented behaviours and business logic
- Parallel-running periods to absolutely de-risk the final switchover
Where it fits
The system nobody wants to touch
A critical internal tool built a decade ago is safely modernised piece by piece in production — avoiding a risky big-bang rewrite.
Tribal knowledge to enterprise documentation
Hidden, undocumented behaviours are mapped and codified, ensuring the system’s survival no longer relies on a single employee’s memory.
Typical stack
- Strangler-fig migration
- TypeScript
- Node.js
- PostgreSQL
- Docker
- AWS
Questions we get asked
Do we have to rewrite everything at once?
No — that is the risk we are avoiding. We modernise incrementally, piece by piece, while the system stays live. A big-bang cutover is the last resort, not the plan.
What if the old system is undocumented?
Mapping the undocumented behaviour is part of the work. We replace tribal knowledge with code and documentation so the system stops depending on one person’s memory.
How do you avoid breaking things in production?
Phased migration with parallel-running periods — the old and new paths run side by side and are compared before anything is switched over.
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Ready to talk?
Tell us what you're trying to build and we'll walk you through how we'd approach it — scope, stack and timeline.
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