Modernize Legacy Applications. Up to 50% Faster.
AI-driven legacy application modernization that moves mainframe, COBOL, and aging .NET or Java systems to cloud-native architecture, with tested rollback and zero-surprise cutover.
- Up to50%faster than a traditional vendor quote
- Up to40%lower total program TCO
- 90%+test coverage on rebuilt modules
- Zeropriority-one cutover incidents
Legacy Systems Tax Everything You Build.
Every new feature, integration, and AI initiative has to work around code nobody wants to touch.
- 01Rising Run CostsLicenses, mainframe MIPS, and scarce skills cost more every year.
- 02Change Takes MonthsTangled dependencies turn small changes into big risks.
- 03No Path to AIMonoliths can't expose the data and APIs that AI needs.
Definition
What Is Legacy System Modernization?
Legacy system modernization is the process of moving aging applications, such as mainframe, COBOL, or older .NET and Java systems, onto modern, cloud-native architecture while keeping the business logic that still works. SMI TechSolutions uses AI-driven code analysis and refactoring to modernize faster, with automated regression testing at every step.
What we do
What We Modernize
Mainframe
FromCOBOL, RPG, PL/IToCloud-native Java, Python, or .NETCut MIPS costs and skills risk without losing business rules.
Monolith
FromTightly coupled monolithToMicroservices or a clean modular monolithAI-assisted decomposition along real dependency lines.
Web Front Ends
FromStruts, JSF, Silverlight, WebFormsToReact or AngularModern UX on top of modernized services.
Cloud
FromOn-premises servers and databasesToAWS, Azure, or GCP with managed databasesRe-architected for the cloud, not just moved.
Testing
FromManual, thin test coverageToAutomated regression suitesTests generated before refactoring prove behavior stays the same.
Approaches compared
Rehost, Replatform, Refactor, or Rebuild?
The right legacy modernization approach depends on how much value the existing code still holds and how far it is from your target architecture. SMI TechSolutions assesses each application and often combines approaches across one portfolio.
| Approach | What changes | Best when | Trade-off |
|---|---|---|---|
| Rehost (lift and shift) | Infrastructure only | You need off a data center fast | Keeps old code and its costs |
| Replatform | Runtime and database | Code is sound but the platform is aging | Limited architecture gains |
| RefactorOur sweet spot | Code structure, same behavior | Business logic is valuable but hard to change | Needs strong regression testing |
| Rebuild | Everything | The system blocks growth and logic is easy to re-specify | Highest effort and change risk |
AI code analysis makes refactoring practical in cases that once forced a costly rebuild.
How we deliver
Our Four-Stage Modernization Method
- 12-3 weeks
Assess & ROI
Claude reads the codebase, maps dependencies, and builds the roadmap and ROI case.
- 23-4 weeks
Architect & Pilot
Target architecture defined; one reference module rebuilt and deployed.
- 312-24 weeks
Production Rebuild
Module-by-module refactor with parallel run and generated regression tests.
- 42-4 weeks
Cutover & Decommission
Rolling, feature-flagged cutover; legacy switched off; runbooks handed over.
- Tested rollback
- Parallel run with diff checks
- Data parity validation
- Zero-retention model endpoints; your code is never used for training
FAQ
Frequently Asked Questions
How do you modernize legacy systems?
SMI TechSolutions modernizes legacy systems in four stages: assess the codebase and ROI, architect the target and pilot one module, rebuild module by module with parallel runs, then cut over and decommission. AI code analysis and generated regression tests keep each stage fast and verifiable.
What is the ROI of legacy system modernization?
The ROI of legacy system modernization comes from lower run costs, faster change, and reduced risk from unsupported technology. SMI TechSolutions builds a TCO baseline covering build, dual running, training, change management, and a 24-month run rate, and has delivered up to 40% lower total program TCO.
How long does legacy modernization take?
A typical SMI TechSolutions program runs 2-3 weeks of assessment, 3-4 weeks of architecture and pilot, 12-24 weeks of production rebuild, and 2-4 weeks of cutover. Scope, code size, and integrations decide where a program lands in that range.
What is mainframe modernization?
Mainframe modernization moves applications written in COBOL, RPG, or PL/I off mainframe platforms onto cloud-native languages and infrastructure, cutting MIPS costs and skills risk. SMI TechSolutions uses AI to read and document mainframe code before refactoring, so business rules carry over intact.
How does AI help with legacy code refactoring?
AI code assistants such as Claude can read 100,000+ lines of legacy code, map dependencies, and summarize the architecture in hours. SMI TechSolutions engineers then use AI to draft refactored code and regression tests, and review every change before it merges.
Can we trust AI-generated code in production?
Yes, when it is tested and reviewed like any other code. SMI TechSolutions targets 90%+ test coverage on rebuilt modules, runs human code review on every change, and produces SBOM and supply-chain attestations. Models run on zero-retention enterprise endpoints.
How do you move a monolith to microservices?
SMI TechSolutions uses AI to map the monolith's dependencies and find natural service boundaries, then extracts services one at a time behind the existing interface. Where full microservices add cost without benefit, we recommend a clean modular monolith instead.
Why does automated regression testing matter in modernization?
Automated regression testing proves the modernized system behaves exactly like the legacy one. SMI TechSolutions generates regression suites from the legacy code before refactoring, then runs them on every change and during parallel runs to catch differences before cutover.
What is the difference between legacy application migration and modernization?
Legacy application migration moves an application to new infrastructure with little code change. Modernization changes the code and architecture so the application is cheaper to run and easier to change. SMI TechSolutions often migrates first to exit a data center, then modernizes in stages.
Is our code used to train AI models?
No. SMI TechSolutions uses frontier models through enterprise endpoints configured for zero data retention, and your code is not used for training. For sensitive workloads, we can run self-hosted open-source models inside your environment.
How do you choose a legacy software modernization company?
Look for a legacy software modernization company with a proven method, tested rollback plans, automated regression testing, experience with your source technology, and pricing tied to outcomes. SMI TechSolutions offers all five, starting with a paid scoping engagement and a fixed-fee build proposal.
Modernize Without the Risk.
Keep the business logic that works, retire the code that slows you down, and cut over with tested rollback.
Free modernization assessment
Codebase review, risk map, and ROI case in 30 minutes.
Talk to a Modernization Expert- Nearly two decades of delivery
