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We modernise legacy applications step by step: keeping what works, replacing what holds you back and preserving the business logic you depend on, without disrupting daily operations.Wij moderniseren legacy software stap voor stap: we behouden wat werkt, vervangen wat je tegenhoudt en bewaren de bedrijfslogica waar je op vertrouwt, zonder de dagelijkse gang van zaken te verstoren.
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Legacy modernization is moving an ageing application to current technology in phases, while the business logic, data and daily operations it supports stay intact. Older software often becomes hard to maintain, extend or secure. We start with an honest look: what still works well, what costs you time and risk, and where modernisation will have the most impact.
The result is a phased plan, prioritised by business risk and technical debt, with no big-bang rewrite. Every step delivers working software you can use.
At ST Engineering, our assessment showed that the existing business logic was limited and only partly reusable. So instead of a straight migration, we kept what still had value, rewrote the software around a modern architecture and then added a lot of new functionality. The software was faster right away, and it is now easier to keep developing. The project is still running.
We migrate component by component, so old and new run side by side and every stage can be rolled back. Your teams keep working with familiar tools while we replace the technology underneath.
Production cannot stop for a software rollout, so we work in steps that can each be rolled back. For ST Engineering we rebuilt an MRO platform for aircraft nacelle repairs in .NET and Angular while the repair process kept running.
We extract the rules from the old system, document them and carry them into the new architecture, then prove with automated tests against the legacy behaviour that the new system does what the old one did. Your domain experts validate each rule with our engineers before anything switches over.
Legacy systems often hold years of undocumented business logic. For Ignite Group we rebuilt a subsidy administration platform built by another party on a modern stack, carrying dashboards, document storage, task flows, reporting and authentication forward with the core functionality intact.
The goal is a system that will not become legacy again in five years. Proven technologies, clean architecture and a design your own team can keep developing long after we are done. Security, performance and compliance are part of the modernisation itself.
AI-supported analysis speeds up the understanding of undocumented behaviour in legacy code and parts of the implementation work, as it did in the Ignite Group rebuild. Developers remain responsible for architecture, validation and delivery quality; nothing AI produces reaches production unchecked.
Not sure whether your system needs a refactor or a rebuild? Book a 15-minute call. We reply within 24 hours.
Schedule a callLegacy systems get harder to maintain, extend and secure every year: frameworks stop receiving security updates, the people who know the code leave, and every new feature takes more effort than it should. The assessment puts those risks in order, so you fix the most expensive one first.
Rehosting moves the application as it is to new infrastructure, refactoring improves the code without changing what it does, rearchitecting changes the structure and replacing rebuilds the application on a new stack. Most modernizations combine several of these per component. In our two published cases the answer was a rebuild on a new stack that kept the proven domain logic.
It depends on the size of the system and how many components can move independently. A focused first release typically takes 2 to 3 months, a full enterprise system 6 to 12 months, always starting with a short discovery and assessment phase.
No. Old and new run side by side while we replace components one at a time, with rollback options at every stage. We switch over per component once tests against the legacy behaviour pass.
Yes. Both published modernization cases involved software built by another party. We start with a review of the code and architecture, then propose a phased plan. Where documentation is missing we reconstruct the rules from the code.
