Services

Replacing the irreplaceable — without taking it offline

Sooner or later, the business-critical system you depend on turns into a liability: the developers who built it have long since moved on, the documentation describes where things stood ten years ago, and every change risks causing problems nobody saw coming. Switching it off is not an option, and neither is standing still: security gaps stay open, engineers who still know the old technology are hard to find, and every new requirement takes longer and costs more. We modernize systems like this where it is hardest: while the system stays live, without interrupting your business.

What you get

  • Step-by-step migration instead of big bang: We break the modernization into stages you can manage and run the old and the new system side by side until every building block has proven itself in production. Your day-to-day business carries on throughout. There is no single go-live date on which everything has to work at once.

  • Systematic knowledge preservation: The most valuable asset in a legacy system is the business rules that have grown into it over decades, documented nowhere but in the code itself. We extract that domain knowledge systematically, AI-assisted through automated code analysis, and move it into the new system in a way that stays traceable.

  • Risk minimization as a method: Every stage comes with defined acceptance criteria, comparison tests against the legacy system and a proven way back. You stay in control at every point and set a pace that suits your business.

  • An architecture with a future: The result is not a “new legacy system” but a maintainable, testable and documented platform that your team or ours can move forward quickly again, including the groundwork for AI integration later on.

  • Security and compliance along the way: Outdated systems are usually the weakest link in a security audit. We bring authentication, encryption, logging and data protection (GDPR) up to today’s standard, following the same ISMS processes (TISAX) we run for the automotive industry.

  • Clarity before the decision: Not every system needs replacing. Our assessment gives you a straight answer on whether an overhaul, a step-by-step rebuild or a completely new build is the most economical route, backed by a defensible estimate of the work involved rather than a ballpark guess.

How we go about it

  1. Analysis: Automated, AI-assisted mapping of the code base, data flows and dependencies, even where documentation is missing.

  2. Strategy: A migration roadmap with stages, priorities and a parallel-operation plan, aligned with the dates your business cannot move.

  3. Implementation: Stage-by-stage migration with comparison tests, continuous sign-off from your business units and a way back at any time.

  4. Operations: Once the old system is retired, we take on long-term responsibility on request: operation, maintenance and ongoing development.

What we build it with

We choose technology for stability, security and longevity, not for its place in the hype cycle:

  • Backends & core systems: Established enterprise platforms such as .NET, complemented by systems-level languages where maximum efficiency is required.

  • Frontend: Modern single-page frameworks for fast, maintainable interfaces.

  • Data: Relational databases (SQL), time-series and NoSQL technologies, including migration of your existing data with completeness verified.

  • DevOps & continuous delivery: Automated build, test and deployment pipelines with mandatory code review: every stage traceable, every release reproducible.

Reference

We rebuilt a risk platform in global energy trading (more than €1bn in transaction volume, business in over 100 countries) from the ground up, during live operation. Not one day of downtime.

How to start

Every engagement starts with a free initial consultation. If required, a fixed-price assessment follows, and the result is yours to keep.

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