AI-driven code modernization

Your legacy code,
rebuilt for the AI era.

We use AI to convert COBOL, PowerBuilder, Delphi, legacy .NET and other aging systems into modern, maintainable, cloud-ready software — and we test hand in hand with you to ensure every module behaves exactly as your business requires before it goes live.

10M+lines converted
90%faster than a rewrite
100%of rules verified & signed off
migration.log
// LEGACY  →  MODERN
IDENTIFICATION DIVISION.
PROGRAM-ID. PAYROLL.
      ⟶  transforming…
public record Payroll(
  Guid Id, Money Net);
✓ logic verified
✓ tests generated
We modernize: COBOL PowerBuilder VB6 / VBA Legacy .NET Delphi Mainframe Something else? Bring your worst case →

What we do

End-to-end modernization, guided by AI and verified by engineers.

Code Conversion

Automated translation from COBOL, PowerBuilder, Delphi, VB6 and legacy .NET into modern languages and frameworks.

Logic Preservation

Every business rule is extracted, documented, and verified so nothing is lost in the cutover.

Test Generation & Sign-Off

Together we build an automated regression suite — from characterization tests that capture your legacy behavior to full end-to-end UI tests (Playwright) that exercise the whole system. Your team reviews and approves every rule, so the new build meets your standard, not just ours.

Cloud Re-platforming

Move from the mainframe and aging desktops to scalable, secure cloud infrastructure.

Database Migration

Modernize VSAM, IMS, Oracle and SQL Server into PostgreSQL and other clean, well-structured stores — often eliminating database license fees along the way.

Ongoing Evolution

Conversion is just the start. We keep modifying, extending and future-proofing your modernized system so it evolves with your business — well into the future.

Language-agnostic by design

Not tied to one target language

Traditional migration tools lock you into whatever stack they were built to emit. Our approach is AI-driven — it works at the level of your business logic and re-expresses it with equal fluency in whichever modern language fits your team. You choose the destination; we're not selling you ours.

.NET 10 / C#

Cross-platform & cloud-ready

Enterprise-grade and easy to hire for — and modern .NET runs natively on Linux, so you keep the ecosystem without Windows licensing.

PHP / Laravel

Web-first business apps

A pragmatic, low-cost target for line-of-business web systems your team — or your MSP — can maintain in-house.

Python

Data & automation

Ideal where the modernized system leans on data processing, integrations, scripting, or ML-adjacent workloads.

C++

High throughput & performance

For performance-critical, high-throughput workloads where every millisecond and every byte counts.

These are common targets, not a fixed menu. The free assessment recommends the best-fit stack for your systems and your team — not a house preference.

Cut the licensing bill

Modern code is only half the savings

Most legacy systems bleed cash on Oracle, SQL Server and Windows Server licensing — every year, whether the capacity is used or not. We're equally at home moving you to PostgreSQL and Linux, so the same workload runs on enterprise-grade, open-source infrastructure with no per-core license to renew. And because modern .NET, PHP and Python all run natively on Linux, even a C# modernization sheds its Windows licensing. Modernization becomes an operating-cost cut, not just a tech-debt cleanup.

  • PostgreSQL in place of Oracle / SQL Server — Enterprise features, zero database license fees.
  • Linux in place of Windows Server — No CALs, no per-core Datacenter licensing.
  • Better performance-per-dollar — A leaner, cloud-friendly footprint that scales without a licensing penalty.

How a migration works

A predictable, low-risk path from legacy to modern.

01

Assess together

A fixed-price, 2–4 week engagement: working side by side with your team, we map dependencies, document your business rules, and deliver a modernization plan you own. The deliverables are yours to keep — whatever you decide next.

02

Convert

Our AI pipeline translates the code module by module while a senior architect reviews every critical path.

03

Verify together

Tests generated from your legacy system's actual behavior prove the new system matches — quirks included. Your team reviews the diff report and signs off before anything goes live. Not a promise — a shared standard.

04

Cut over — together

Module by module, with your team in the room. The old system stays live until you and we agree each piece has proven parity. Then documentation, knowledge transfer, and ongoing support.

We verify together — before a line is converted

Before any code is converted, we sit down with your team to extract, document, and sign off every business rule in plain English. Then we generate tests from your legacy system's actual behavior. Your team approves the rules. Our code has to pass the tests. Here's what that looks like on a real VB6 billing routine.

Billing.bas — VB6 (before)
Public Function CalcLateFee(InvAmt As Currency, _
                            DaysLate As Integer) As Currency
    Dim Fee As Currency
    If DaysLate <= 0 Then
        CalcLateFee = 0
        Exit Function
    End If
    Fee = InvAmt * 0.015
    If DaysLate > 30 Then
        Fee = Fee + (InvAmt * 0.005 * Int(DaysLate / 30))
    End If
    If Fee > InvAmt * 0.1 Then Fee = InvAmt * 0.1
    CalcLateFee = Fee
End Function
Billing.cs — C# / .NET 10 (after)
public static decimal CalcLateFee(
    decimal invoiceAmount, int daysLate)
{
    if (daysLate <= 0) return 0m;

    var fee = invoiceAmount * 0.015m;
    if (daysLate > 30)
        fee += invoiceAmount * 0.005m * (daysLate / 30);

    var cap = invoiceAmount * 0.10m;
    return Math.Min(fee, cap);
}

Your team owns the rules. We prove the code matches.

We extract every business rule from the legacy code and write it in plain English. Your subject-matter experts review, correct, and sign off each one before a single line of new code is written. No rule goes into the converted system that your team hasn't approved.

Late fee = 1.5% of the invoice, plus 0.5% for each full 30-day period overdue beyond the first 30 days, capped at 10% of the invoice. No fee if not overdue.

✔ Signed off by: Billing Team Lead, Accounts Receivable Manager

BillingTests.cs — generated parity tests
[Theory]
[InlineData(1000, 0, 0)]        // not overdue: no fee
[InlineData(1000, 15, 15.00)]   // base 1.5% only
[InlineData(1000, 45, 20.00)]   // base + one 30-day period
[InlineData(1000, 900, 100.00)] // capped at 10%
public void CalcLateFee_matches_legacy_behavior(
    decimal amount, int daysLate, decimal expected)
    => Assert.Equal(expected, Billing.CalcLateFee(amount, daysLate));

✓ 4 passed — converted code matches legacy behavior
Partner program

You keep the client. We handle the legacy.

MSPs, fractional CIOs, and dev agencies: when a client is stuck on a system nobody on your team wants to touch, send it to us — and get paid for it.

Referral

15%

of assessment + project fees

Make an introduction — we sell and deliver, you collect commission as client payments clear. Zero effort beyond the intro.

Accelerator

20–30%

volume-based commission

Co-sell with us: join the calls, own the relationship, help close. Higher effort, higher share — rates climb with each deal.

White-label

Your margin

on top of wholesale pricing

We deliver under your brand and stay invisible to the end client. Your client sees one agency that can do anything.

No exclusivity, no quotas, 12-month deal registration protection — and a full partner kit to sell with.

Become a partner

The questions every CIO asks

Straight answers to the hard ones.

Together we generate characterization tests from your legacy system — capturing how it actually behaves, quirks included — plus automated end-to-end regression tests (Playwright) that drive the real UI, so nothing slips through. Your team reviews the results as we run old and new side-by-side on real data. You sign off on the diff report before anything goes live.

Every extracted rule is written down in plain English and signed off by your team before conversion begins. If a rule is wrong in the document, we catch it before a single line of new code exists — which is more review than the legacy code ever got.

This isn't a rewrite — it's a conversion with the original system as the executable spec. Fixed price, module-by-module milestones, and the legacy system stays live until each module proves parity. Worst case, you keep what you have.

No. Code is processed under NDA through enterprise AI deployments with no-training guarantees — or client-hosted environments where required. Data handling terms are written into the contract. Full details on how we handle your code.

It starts with a fixed-price $25,000 assessment (2–4 weeks): a full inventory of your legacy estate, your business rules documented, a risk map, and a fixed-price modernization quote. Those deliverables are yours to keep even if you stop there. The big consultancies quote $2–5M for what we typically deliver for a fraction of that.

You get full documentation, the generated test suite, and knowledge transfer to your team or MSP — plus an optional support retainer. You're never locked in: the deliverable is standard, mainstream code in whichever stack your team runs — .NET, PHP, Python, or otherwise — that any developer can maintain.

Still running code older than your newest hire?

Tell us what you're running. We'll give you a free, no-obligation modernization assessment — usually within one business day.

Got something obscure, undocumented, or half-dead? That's exactly what we like. Bring your worst case.

No obligation · How we handle your code · or email hello@legacy-to-ai.com