Legacy application modernization,
without the big-bang rewrite.
Skilak Consulting modernizes the aging systems your business actually runs on — Access databases, VB6 and .NET Framework applications, Excel/VBA workbooks — moving them to modern, supported technology incrementally, so your operation never stops while the system transforms under it.
The business logic in that old system took years to encode. We preserve it, document it, and carry it forward — we don't ask you to bet the company on a rewrite.
Sound familiar?
- It only runs on one aging machine — and everyone is afraid to restart it
- One person (or one departed developer) is the only one who understands it
- Multiple users mean crashes, locking errors, or "wait until Carol's out of the file"
- The vendor, framework, or runtime is end-of-life and security patches have stopped
- It can't talk to the modern tools the rest of your business runs on
- Every new report or field takes weeks — or is simply "not possible anymore"
These aren't IT annoyances — they're business risk concentrated in software nobody can safely touch. Modernization converts that risk back into an asset.
Common modernization paths
| From | To | How |
|---|---|---|
| Microsoft Access database | Modern web application (PostgreSQL / SQL Server) | Dedicated migration practice — see our Access database replacement service |
| VB6 / WinForms application | .NET 8+ web or desktop application | Behavior-preserving rewrite in slices, with the original as the reference implementation |
| .NET Framework 4.x | .NET 8+ (LTS) | Incremental migration — dependencies, then projects, then runtime — with tests locking behavior |
| Excel / VBA workbooks | Web application with a real database | Extract the logic, kill the copy-paste chains, keep the familiar workflows |
| On-premises server apps | AWS or Azure cloud infrastructure | Lift, containerize, or re-platform — chosen per system, defined in Terraform |
How we de-risk it
Audit & document
We read the code, map the data, and interview the people who use it. You get a written assessment of what exists, what's risky, and what modernization should cost — useful even if you never hire us.
Stabilize
Backups, source control, monitoring, and fixes for the scariest failure modes first. The system stops being a time bomb before we change what it does.
Modernize in slices
The strangler-fig approach: new functionality replaces old piece by piece, running side-by-side. Your business never stops while the system transforms under it.
Cut over & support
When the new system has proven itself on real work, we retire the old one — and stay on for support, changes, and the next improvement.
Frequently asked questions
What is legacy application modernization?
Legacy modernization is upgrading or replacing aging business software — Access databases, VB6 apps, old .NET Framework systems — with modern, supported technology while preserving the business logic and data your operation depends on. Done well, it's incremental: the business never stops running.
Why not just rewrite the whole system from scratch?
Big-bang rewrites fail at a famous rate: they take longer than promised, and the old system's undocumented edge cases — the real business rules — get lost. We modernize in slices, keeping the old system as the reference until each piece of the new one proves itself on real work.
Our original developer is gone and nothing is documented. Can you still help?
Yes — that's the most common situation we walk into. We start by auditing the code and data as they actually exist, producing written documentation of what the system does. That audit is a standalone deliverable you keep regardless of what happens next.
How much does legacy modernization cost?
A paid audit typically runs $3,000–$10,000 and produces a fixed quote for the work itself. Small system migrations often land in the $15,000–$50,000 range; larger multi-module platforms more. The audit means you get a real number, not an estimate that doubles later.
Can you keep our data during a migration?
Yes — data migration is half the job and we treat it that way: full extraction, cleaning, validation against the old system's numbers, and parallel-run verification before cutover. Nothing is deleted until the new system has proven itself with your real data.
Let's build something real.
Have a project, a legacy system that needs attention, or a contract to discuss? We respond within one business day.