We modernize your systems without stopping your business.
Replacing a legacy system isn't installing a new program. It's redesigning how the business runs while preserving continuity. We do this for AS/400 systems, custom 2000s-era ERPs, Visual Basic applications, and Excel-driven processes that have grown over the years.
What we do, concretely, in legacy system modernization.
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AS/400 migration to cloud-native architectures
We move your AS/400 (RPG/COBOL) to a modern stack while preserving business logic and integrations with the existing network. Progressive approach, business continuity guaranteed.
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Legacy custom ERP replacement
We rebuild custom management software from the 2000s with modern architectures, preserving historical data and the features you actually use. No "everything at once": module-by-module release.
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Excel-driven process conversion
We turn Excel spreadsheets that have become the "operational brain" of a critical process into dedicated software with multi-user access, audit trail, and integration with other systems. We eliminate the single-file risk.
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Visual Basic 6 and Access modernization
We rebuild legacy desktop applications as modern web apps, preserving the workflows users already know to reduce the impact of change. The learning curve is minimal.
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Monolith to distributed-architecture migration
We break rigid monoliths into smaller, independent services where a full refactor isn't realistic. Strangler pattern: the legacy is "consumed" one module at a time.
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Integration of disparate systems
We connect management software, CRMs, ERPs, e-commerce platforms and warehouse systems into a coherent architecture, without throwing away what already works. API layer + middleware, not rewrites.
How we work, specifically.
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01 AUDITWe map the existing legacy system: code, data, integrations, knowledge scattered across the team. 4–8 weeks.
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02 STRATEGYWe decide on the approach (full replacement, gradual refactoring, strangler pattern) with realistic assessment of risks and timelines.
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03 PLANMilestone roadmap with rollback criteria for each phase. No migration without a written plan.
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04 MIGRATIONWe work in small increments, keeping the old system running in parallel until the new one is validated in production.
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05 HANDOVERComplete documentation, internal team training, operational support for the first 3–6 months post-go-live.
Specific solutions for legacy system modernization.
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AS/400 migration to the cloud
Move RPG/COBOL to a modern stack while preserving business logic.
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Custom ERP replacement
Rebuild of 2000s management software with complete data migration.
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From Excel to dedicated software
When the spreadsheet has become the operating system of a critical process.
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SAP alternatives for mid-sized companies
When SAP is too much, but you need more than a basic management system.
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Visual Basic 6 to modern migration
From legacy desktop apps to modern web apps while preserving workflows.
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Legacy systems integration
API and middleware on top of systems that aren't ready for a rewrite.
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COBOL modernization in Italy
For those still running COBOL in production with zero up-to-date docs.
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Monolith refactoring
Strangler pattern to decompose without stopping the business.
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Electronic invoicing automation
SDI cycle integrated with management software, warehouse and accounting.
Where modernization works best.
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Manufacturing
AS/400 and legacy MES very common, long production lifecycles.
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Distribution
Custom 2000s management software is common, integration with modern e-commerce.
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Finance
Legacy mainframe systems, regulatory constraints on operational continuity.
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Professional services
Excel-driven processes everywhere, poor multi-user support, zero audit trail.
Frequently asked questions.
How long does it take to modernize an AS/400?
Between 6 and 18 months depending on the complexity of the existing code and the level of customization. Projects with a simple architecture and few customizations wrap up in 4–6 months; systems with years of accumulated layers need 12–18 months of gradual work to avoid disrupting operations. We always start with a 4–8 week audit to estimate real timelines.
How much does it cost to replace a custom ERP?
Legacy custom ERP replacements start at €60,000–120,000 for mid-sized companies (50–200 employees) for baseline projects, rising to €200,000–500,000 for heavily customized ERPs with multiple integrations. The main cost factor is the number of business processes to preserve and the level of tribal knowledge hidden in the current system.
Can I do the migration without stopping the business?
Yes. We use progressive migration strategies (strangler pattern, parallel run, feature flags) that keep the legacy system running while the new one is introduced module by module. Each phase has defined rollback criteria, and the final go-live only happens once the new system is validated in production. Typically there is no business-significant downtime.
What happens to historical data during the migration?
All historical data is migrated to the new system with automatic pre/post-migration consistency checks. For very large data sets (>10TB) we use incremental differential migration. We keep the legacy system accessible in read-only mode for at least 12 months post-go-live as a historical fallback, before considering definitive decommission.
Do I need to train the team on the new system?
Yes, but the load is designed to be minimal. The new system mirrors legacy workflows where possible, reducing the learning curve. We provide targeted training (8–16 hours split into sessions) for power users, operational documentation, video tutorials, and dedicated support for the first 3–6 months post-go-live.
How do you manage the risk of a failed migration?
Three layers of mitigation: (1) an initial audit that identifies technical risks before commitment, (2) an incremental approach with per-phase rollback instead of big-bang, (3) parallel run where legacy and new run together until the new is validated. Any stop arrives during the audit phase, before the main investment, not after the project has started.
Can we modernize only part of the system and keep the rest?
Yes, this is one of the most common approaches. We identify the modules with the best cost/benefit ratio (typically customer-facing or highly-edited business logic) and modernize them first, leaving the rest of the legacy in API-wrapper mode. It lets you spread the budget over 2–3 years and reduce the risk of a monolithic go-live.
Got a case to tell us about? Let's begin.
A real conversation with the people who will build the software. No automated quotes, no sales bots.