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Legacy application modernization

Q: How does AI accelerate modernization?

Simplifying complex analysis: Analyzing complex application landscapes can be time-consuming and costly. T-Systems AI tools such as AI Engineer accelerate application, dependency, and architecture analysis, helping define target architectures faster. Increasing code transformation accuracy: AI supports code translation and modernization, while experts validate and refine outputs using business and technical knowledge. Accelerating testing: AI automates test case creation and execution, while teams ensure governance, quality, and alignment with business requirements.

Modernize legacy applications with AI and automation to cut risk, cost, and skills gaps

How can you keep critical legacy applications future-ready?

Business-critical applications often outlive the technologies they depend on. Unsupported platforms, aging code and scarce expertise increase costs, risk and complexity. T-Systems modernizes these applications while preserving proven business logic, using AI to accelerate analysis, code transformation, testing and verification for faster, lower-risk modernization.

Common scenarios – and how to master them

Your challenges

Critical applications rely on unsupported technologies
Legacy skills shortages increase cost and risk
Poor documentation and complex code delay innovation
Security, compliance and integration demands keep growing

Our approach

Business-led modernization aligned with strategic goals
End-to-end delivery from advisory through managed services
AI-powered analysis, code transformation, testing and documentation
Legacy-to-cloud modernization with minimal business disruption

Key benefits at a glance

Faster modernization

Time and effort savings

AI-supported modernization transforms critical applications faster and uses your budget more efficiently

Use of sovereign AI

Secured data

Use AI confidently in a secure and sovereign T-Systems environment

Reduced transformation risk

25+ years of experience

Modernize complex applications while protecting business continuity and core logic

Real world results and success stories

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FAQ

What is legacy application modernization?

Legacy application modernization updates business-critical applications that depend on outdated or unsupported technologies. T-Systems helps preserve valuable business logic while replacing technical constraints with supported, maintainable technologies that are easier to secure, integrate and evolve.

Which applications are suitable?

The service targets enterprise applications whose operating systems, frameworks, programming languages or architectures are aging or no longer supported. They typically add to technical debt, struggle to scale with growing workloads or keep pace with changing core processes, while increasing maintenance costs due to legacy code. Mainframe applications are addressed through T-Systems' dedicated mainframe application modernization offering.

Why modernize instead of replace?

Many older applications contain years of proven business logic and process knowledge. Modernization can retain this value while reducing technology risks, maintenance effort and dependency on hard-to-find specialized expertise. The right approach depends on business value, technical condition, dependencies and future requirements.

How does AI accelerate modernization?

Simplifying complex analysis: Analyzing complex application landscapes can be time-consuming and costly. T-Systems AI tools such as AI Engineer accelerate application, dependency, and architecture analysis, helping define target architectures faster.
Increasing code transformation accuracy: AI supports code translation and modernization, while experts validate and refine outputs using business and technical knowledge.
Accelerating testing: AI automates test case creation and execution, while teams ensure governance, quality, and alignment with business requirements.

What business benefits can you expect?

Modernization can reduce maintenance effort and technology risk, improve security and maintainability, broaden access to available development skills and make future changes faster. It also creates a stronger foundation for integration, automation and continued digital innovation.

Why choose T-Systems?

As a Deutsche Telekom company, T-Systems combines broad cross-industry experience with strong enterprise application, cloud and DevOps expertise. With access to advanced AI resources and infrastructure, AI Engineer capabilities already used in 120+ active projects, and strong industry partnerships, T-Systems can accelerate transformation while experienced teams manage architecture, quality and risk.

Ready for the next step?

Accelerate legacy modernization with AI, automation, and cloud-native transformation from T-Systems.