NeoTek Solutions delivers legacy application modernization: we move aging business software to current technology and the cloud in small, reversible steps instead of a risky “big bang” rewrite. It suits IT and operations leaders at mid-size and enterprise organizations whose critical systems are costly to change and hard to staff. Our Nashville engineers use AI tools to understand old code quickly and protect current behavior with tests before anything changes.

Many organizations rely on software that is older than most of the people maintaining it. It still runs billing, scheduling, claims, inventory or production work, and it takes a larger share of the IT budget each year. With our approach, your business keeps running the whole time.


When Is It Time to Modernize a Legacy Application?

  • Only one or two people understand how the system works
  • Small changes take weeks and often break something else
  • The platform, language version or database is out of vendor support
  • Security or compliance reviews keep flagging the same system
  • Hosting and licensing costs keep rising
  • You can’t connect the application to newer tools, APIs or AI features

Who This Is For

Our modernization work fits teams in healthcare, manufacturing, logistics, financial services and government. Common examples of aging systems include:

  • Applications built on older stacks, such as classic ASP, Visual Basic 6, early .NET Framework, older Java EE or PowerBuilder
  • COBOL or other mainframe-era programs that feed modern systems
  • Access databases and spreadsheet-driven tools that grew into critical systems
  • On-premises applications running on aging servers

How Does AI Change Legacy Modernization?

The hardest part of modernization is usually understanding what the old system actually does. Documentation is missing or wrong, and the original authors are gone. AI tools now make this discovery work far more practical.

AI-assisted code analysis and documentation

We use AI tools to read through large codebases and summarize modules, data flows and business rules. They help map dependencies, find dead code and draft documentation. Experienced engineers verify every finding against the running system, because AI can misread unusual code.

Characterization tests before changes

Before we change anything, we capture what the system does today. Characterization tests record current behavior, including quirks your users depend on. AI helps generate these tests at scale, and engineers review them. When the new version passes the same tests, you have evidence it behaves the same way.

Faster translation of routine code

Coding assistants, such as GitHub Copilot, Claude Code or Cursor, help convert repetitive code patterns to a modern stack. Engineers review every change. Complex business logic and architecture decisions stay with people, since AI is weaker at domain judgment and novel design.


Our Modernization Approach

  1. Assess

    We inventory the application, its integrations, data and users. AI-assisted analysis speeds up code review and documentation. You get a clear picture of risks, options and a recommended path.

  2. Plan the target

    We choose the target architecture and stack with you, such as .NET, Java, Python or JavaScript/TypeScript. Together we decide what to rehost, refactor, rebuild or retire. The plan is sequenced so each step delivers value on its own.

  3. Protect current behavior

    We build characterization tests and set up a CI/CD pipeline, the automated system that builds, tests and deploys code. This safety net is in place before any migration work starts.

  4. Migrate incrementally

    We use the strangler-fig approach. New components grow around the old system and take over one function at a time. Traffic moves gradually, and the old code is retired piece by piece. If a step causes problems, we can route traffic back.

  5. Migrate the data

    Data migration gets its own plan. We profile and clean data, map old structures to new ones and run repeated test migrations. Reconciliation checks confirm records match before cutover. For larger data platform work, see machine learning and data engineering.

  6. Cut over and retire

    We schedule final cutovers around your business calendar, with rollback plans ready. Once the new system is stable, we decommission the old one and hand over documentation.


Cloud Migration on Azure, AWS and Google Cloud

Many modernization projects include a move to the cloud. We help you choose the right option for each workload:

  • Rehostto cloud virtual machines when speed matters most
  • Replatformto managed databases and app services to reduce maintenance
  • Refactorinto cloud-native services where the long-term benefit justifies the effort

We set up infrastructure as code, monitoring, backups and access controls. We also plan for cost, so the cloud bill doesn’t surprise you after launch.


Reducing Risk While Systems Keep Running

  • No big-bang cutoversSmall, reversible steps limit the impact of any single issue.
  • Parallel running where neededYou can compare old and new outputs before switching over.
  • Human review of all AI outputEvery AI-generated change is reviewed by experienced engineers, tested and security-scanned.
  • Security built inWe design for HIPAA and other requirements and work within your compliance program. Learn about our AI governance, security and compliance work.
  • Your IP stays yoursYou own the modernized code. Your code and data are not used to train public models.
  • Knowledge transferYour team gets current documentation and walkthroughs, so you no longer depend on one expert.

Why NeoTek Solutions

Modernization takes solid engineering and people who can read old code. We bring an AI-accelerated software development process with senior oversight at every step. Through AI and IT staffing, we can also add engineers who know both older and modern stacks.


How Can NeoTek Solutions Help You Modernize?

You do not have to choose between leaving the system alone and replacing it all at once.

  • Work we deliverAI-assisted code analysis and documentation, characterization tests, incremental migration, data migration and cutover, and retirement of the old system.
  • Older stacks includedClassic ASP, Visual Basic 6, early .NET Framework, older Java EE, PowerBuilder, COBOL programs feeding modern systems, and spreadsheet-driven tools that became critical.
  • How we workShort cycles with AI-assisted delivery and human review, acceptance criteria agreed early and small reversible steps, so progress and cost stay visible throughout.
  • Skills on the teamSoftware engineers who read both older and modern code, data engineers, cloud and security specialists and QA, so code, data, hosting and testing are covered by one team.
  • What makes us differentWe use AI in how we work, not only in what we deliver, so old code gets analyzed and covered by tests at a scale manual review rarely reaches.
  • Your IP stays yoursYou own the modernized code, your data never trains public models, and the documentation we hand over ends your dependence on a single expert.

Modernizing on your own schedule usually costs less than modernizing under pressure. Book a free AI consultation and we will look at what an assessment would cover.


Frequently Asked Questions

Will you have to rewrite the whole application?

Usually not. We mix approaches on most projects: rehosting some parts, refactoring others and rebuilding only where it pays off. Our strangler-fig approach replaces the system gradually while it keeps running your business.

How do you use AI on our legacy code?

We use AI tools to summarize large codebases, map dependencies, draft documentation and generate characterization tests. They also speed up translating repetitive code. Our engineers verify every finding against the running system and review every change.

How do you protect what the system does today?

Before we change anything, we build characterization tests that record how your system behaves now, including the quirks your users depend on. They act as our safety net. If the new version produces different results, the tests catch it before your users do.

Will our system be down during migration?

We plan to avoid disruptive downtime. We migrate in small steps and schedule cutovers around your business calendar. Where a short outage is unavoidable, we agree the timing with you in advance and keep a rollback ready.

Which clouds do you work with?

We work with Azure, AWS and Google Cloud. We help you pick the best fit based on your existing contracts, skills, security needs and costs.


Get a Clear Modernization Plan

Tell us about the system that worries you most. We will talk through options, risks and a practical first step. Book a free AI consultation

Take the free AI readiness assessment