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Legacy application modernization · AI-accelerated · Operator-verified

Any legacy application. Modernized — without stopping the plant.

FoxPro. Access. VB6. Green screens. The in-house ERP someone wrote in 1999 that still runs the business. With AI reading the code and drafting the build, and forty years of manufacturing experience deciding what it should become, we take the application nobody wants to touch and turn it into a modern, bespoke system with a workflow built for how the work actually flows — module by module, reconciled at every step, so the business never stops running on software it trusts.

// reverse-engineer first · rebuild module by module · every module reconciled to the old one before cutover
MODERNIZED FROM:FOXPROACCESSVB6CLIPPER / DBASECLASSIC ASPGREEN SCREENIN-HOUSE ERPSPREADSHEET SYSTEMSORPHANED VENDOR APPS
Why now

The economics of modernization just changed.

For twenty years the honest advice to a manufacturer running a 1990s in-house system was: don't touch it. The rewrite cost more than the company could justify, the vendor pitch was a seven-figure ERP, and the person who knew the old system was still in the building.

Two of those three things are no longer true. The person is retiring. And AI has collapsed the cost of the part that made rewrites expensive — reading thousands of lines of undocumented code, mapping the schema, drafting the specification, generating the first cut of the new module, writing the tests. What took a bench of six now takes a small senior team and an overnight build cycle.

The third thing hasn't changed, and it's the part that matters. Somebody still has to decide what the system should become — which workflow to keep, which to kill, what the number has to tie to. That's judgment, and it comes from having run the P&L, walked the floor, and administered the ERP. AI supplies the leverage. We supply the judgment. You get a modern system that fits your business, at a cost that used to buy a requirements document.

AI reads the old code in an afternoon. Forty years decides what it should have said.
25 yrsa FoxPro ERP our principal wrote for a foundry consumables manufacturer — still running, now being rebuilt plank by plank on a modern web stack
Phase 0an undocumented Access QMS fully reverse-engineered before a line of migration code — then rebuilt as a modular quality portal
2000the first "second skin" — a system wrapped around a foundry's ERP that the client used more than the ERP itself
0big-bang cutovers. Every module replaces its predecessor only when it has been reconciled on real data
How it's done

Reverse-engineer. Rebuild a module. Reconcile. Repeat.

The method is boring on purpose. It's the same one that has kept a 25-year-old ERP running through its own replacement.

01

Phase 0 — understand it fully

Before any migration code: the legacy system is read end to end — code, schema, reports, the workarounds in people's heads — and documented. AI does the reading; we verify it against how the business actually uses the system. Most clients get the first real documentation of their system out of this step alone.

02

Design the workflow, not the screens

Where does the operator re-key the same number? Where does approval live in an email? Where is the exception hunted for instead of surfaced? The new module is designed around the answer — barcode capture, role-based screens, the right action made the easy action.

03

Build and reconcile

AI-accelerated build on a modern web stack, then the part that decides everything: the new module runs beside the old one on real data until every difference has a root cause. No demo on unvalidated data. Ever.

04

Cut over one module. Repeat.

The old module is retired only when the new one has earned it. Each cutover pays for the next. Documentation, tests and a runbook ship with every module, so your team — or anyone — can maintain it after we're gone.

What comes out the other side

A bespoke system that fits the business — not a rewrite of the old one.

WORKFLOW

Built around how the work flows

Role-based screens, barcode and scanner capture where the workflow demands it, approvals in the system instead of the inbox, exceptions surfaced on a dashboard instead of discovered at month-end.

DATA

One clean model, with lineage

The legacy data migrated with every record traceable to its source, duplicates and orphans resolved on the way in, and the schema documented — so reporting finally reads from one truth.

CONNECTED

Talks to everything you already run

Any API you have, or one we build. ERP, CRM, PLM, EDI, e-invoicing, corporate feeds. The integration discipline →

STACK

Modern, ordinary, maintainable

TypeScript, React, Node, SQL Server or Postgres, containers. On-prem or Azure — your IT policy decides. Nothing proprietary to us; any competent shop can maintain it.

RUNNING

Monitored from day one

Logging, alerting, backups that are proven to restore, and a runbook — shipped with the system, not bolted on after the first outage. How we keep systems running →

INTELLIGENT

Ready for the AI layer

A clean canonical model means Clairvient can sit on top: the morning digest, ranked exceptions, the "Why?" drill to source. Clairvient →

From the ledger

Modernizing an ERP our principal wrote — decades later.

Decades ago our principal wrote a foundry consumables manufacturer's ERP in FoxPro. It has run their business ever since — a testament to fit, and a growing liability. They needed a path to a modern web platform without betting the company on a rip-and-replace, from a partner who understood every quirk of the system. Fortunately, one was available.

The conversion is piece by piece: each module replaced only when its successor is proven, so the business never stops running on software it trusts. AI-accelerated development makes an incremental path economical that would have been unaffordable at consulting rates a few years ago. Twenty-five years of institutional knowledge conserved instead of discarded — the Ship of Theseus, rebuilt plank by plank while it sails.

Read the problem-led case: the app nobody can maintain anymore →

Straight answers

Questions about modernization.

What counts as a 'legacy application'?
Anything the business depends on that nobody wants to touch: FoxPro, Access, VB6, Clipper, dBase, classic ASP, an old Java or .NET app, a green-screen system, a spreadsheet that became a system, a vendor product whose vendor is gone. If it runs your operation and the last person who understood it is retiring, it qualifies.
Do you rewrite it all at once?
No. Big-bang rewrites are how companies lose a year and a controller. We reverse-engineer and document the existing system first, then rebuild module by module — each new module replacing its predecessor only when it has been reconciled against the old one on real data. The business never stops running on software it trusts.
What does AI actually do here — and what doesn't it do?
AI reads the legacy code and schema in hours instead of weeks, drafts the specification and the data migration scripts, generates the first cut of the new module, and writes the tests. What it doesn't do is decide what the workflow should be, or sign off that the numbers tie. That's forty years of manufacturing experience, and it's the part you're paying for. AI is the leverage; the judgment is ours.
What stack do you build on?
Modern web: TypeScript, React, Node, SQL Server or Postgres, containerized, deployable on-prem or on Azure — whichever your IT policy wants. Nothing exotic, nothing proprietary to us. Your team, or any competent shop, can maintain it after we're gone, which is the point.
How is 'modernized workflow' different from a rewrite?
A rewrite reproduces the 1998 screens in a browser. A modernized workflow asks why the operator keys the same number into three places, why approval lives in an email chain, why the count sheet is printed and re-typed — and builds the new system around how the work should flow, with barcode capture, role-based screens, and the exceptions surfaced instead of hunted for.
Let's talk

Tell us about the system nobody wants to touch.

What it's written in, what it runs, who still understands it, and what happens if it stops. That's enough for a straight read on whether it's a modernization candidate and what the first module would be.

You'll get a straight answer and a tight scope. If we can't help, we'll tell you that too — and usually who can.

No newsletter. No drip sequence. Just a reply from us.

Got it — thanks.

We read every one of these ourselves. Expect a reply within one business day. If it's urgent, email us directly at dan.mindlin@mindlinconsulting.com.