
Digitization has revolutionized healthcare. What was primarily an administrative support is today the **backbone of patient care**. Modern clinics and medical practices are unthinkable without efficient IT systems. Whether Kr...

For B2B teams we modernise legacy systems step by step. We start with a fixed-scope analysis, then move to phased migration with parallel operation. Production stays online and milestones stay transparent. Made in Germany from Lower Saxony.

„Modernisation pays off when each step reduces risk: parallel run, validated data migration and a clear decommission plan beat a single big-bang cutover.“

„Legacy programmes survive when owners accept measurable milestones—otherwise "rewrite someday" blocks every budget cycle.“
Analysis of Existing Legacy Systems
Comprehensive analysis of your existing systems to identify modernization potential.
Modernization Strategies
Development of customized modernization strategies for your systems.
Gradual Migration
Step-by-step migration with minimal business disruption.

„Refactoring without tests is guesswork: characterise behaviour first, then carve boundaries the strangler pattern can eat safely.“
Frequently Asked Questions
Typical signs: Increasing maintenance costs, performance problems, lack of interfaces, security concerns, or the technology is no longer supported. We offer a free initial assessment.
Yes, we regularly take over systems where only the code exists. Through reverse engineering and structured analysis, we understand the logic and document it for the future.
Depends on the situation. Often a gradual migration makes sense: new functionality on new technology, old system runs in parallel until it's replaced. We analyze costs and risks with you.
Yes, that's usually the goal. We plan data migration carefully, validate quality, and ensure no business-critical information is lost.

Plan modernization? We analyze your system and develop a pragmatic migration strategy.
Schedule ConsultationHighly dependent on scope and complexity. A small application from 15,000 €, larger enterprise systems correspondingly more. We start with an assessment to get a realistic estimate.
Small systems: 2-4 months. Complex migrations: 6-18 months. We work in sprints and deliver usable results early, so you can see progress and give feedback.
Through gradual migration, parallel operation of old and new systems, comprehensive testing, and rollback strategies. We never switch everything at once.
Not uncommon with legacy systems. We work ourselves into the code, analyze structure and logic, and build a new knowledge base. This takes time but is feasible.

Questions about modernization? We advise honestly about possibilities, costs, and risks – from experience with many legacy projects.
Contact UsLegacy systems are often the backbone of successful businesses. They run critical processes that generate revenue every day.
The problem is not that they work poorly today. They grow expensive to maintain. They are hard to integrate with modern tools. They face security threats that did not exist when they were built.
Our modernization practice helps companies preserve the business logic in these systems. We migrate toward contemporary platforms that support future growth.
We have modernized applications written in Delphi, Visual Basic 6, COBOL, FoxPro, and classic ASP among many others.
Each legacy technology brings unique challenges. Examples include proprietary data formats and undocumented business rules buried in thousands of lines of code.
Our reverse engineering process extracts this institutional knowledge. We document it properly. We translate it into modern architectures.
Nothing valuable gets lost during the transition, even when the original developers are long gone.
The strangler fig pattern is our preferred modernization strategy for most enterprise systems.
We avoid a risky big-bang rewrite. We gradually replace legacy components with modern services. The old system keeps running in parallel.
New features ship on the modern platform. Existing functionality moves module by module.
This approach cuts project risk. The business does not depend on an unproven system. Each migration phase delivers immediate, measurable improvements.
Data migration deserves special attention in any modernization project. Legacy databases often hold decades of business history.
We build migration strategies that include data cleansing, format transformation, and thorough validation. We aim for every record to transfer correctly.
Our parallel-run testing compares outputs from old and new systems side by side. We catch discrepancies before cutover.
The result is a smooth transition. It preserves data integrity and business continuity through the full modernization journey.
Every legacy system carries technical debt — shortcuts and compromises that have built up over the years. Before modernising, we run a thorough Technical Due Diligence. We review code quality, architecture and dependencies, then create a prioritised roadmap. You get a clear picture of which problems are urgent and which can wait for gradual refactoring. This transparency is the foundation for realistic timeline and budget planning.
Many legacy systems have grown into a monolith — a single, tightly connected application that is hard to scale and maintain. Our approach is gradual. We break the monolith into loosely coupled microservices, packaged in Docker containers and managed with Kubernetes. We use the Strangler Pattern: new features are built as separate services while the monolith keeps running and slowly shrinks. This removes the risk of a big-bang cutover. Your team learns the new architecture one step at a time.
Data migration carries the highest risk in any modernisation project. That is why we give it the most attention. Decades of business data must be moved, transformed, cleaned and validated. We build automated migration scripts that are repeatable and testable. Before the production switch, data goes through multiple dry runs in a staging environment until every record is verified. We only proceed with the cutover when old and new systems produce identical results. Rollback options are in place at all times.
Modernisation decisions often sit alongside new product work, ERP programmes and integration projects. Browse these links for further reading on legacy strategy.
Up to 50% of your investment via BAFA/KfW
Use our funding calculator to see which government grants may apply to your project.
Service cluster
Related services for Integration & Interfaces
Connect systems, stabilize data flows, and gradually modernize legacy – without big-bang risk.
Related topics
Complementary services from other areas
These services are frequently requested together with Legacy Modernization or complement it thematically.
Software & Platforms
Operations, Support & Stabilization
Consulting & Strategy
Legacy Modernization is most effective when it is aligned with your business goals, existing systems, and team capabilities. At Groenewold IT Solutions we combine product thinking, clear architecture, and hands-on delivery so that every project delivers measurable value. We address operational, compliance, and performance aspects early so that later releases stay on track.
Our approach to Legacy Modernization emphasises transparent backlogs, close collaboration with your stakeholders, and incremental delivery. Whether you need a discovery workshop, an MVP, or a full-scale implementation, we define scope, effort, and success criteria up front. With over 250 completed projects we have the experience to recommend the right level of investment and the right next steps for your situation.
Explore our services overview for the full portfolio, our topic pages for in-depth articles linked to each service, and the IT Glossary for key terms. For books and practical guides by Björn Groenewold, see publications. If you would like to discuss your project, we are happy to clarify scope, priorities, and a realistic timeline in a short consultation.
Decision guidance
Our topic overview links related articles and entry points alongside this service page.
Book a short, no-obligation intro call about Legacy Modernization – straightforward next steps.
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