Large-scale migrations · .NET

.NET migrations, end to end.

Framework, WebForms, VB.NET, COM interop, mixed C#/VB solutions. Parity proof at every step.

Why .NET migrations stall

Business logic is buried

It lives in WebForms code-behind, stored procs, and ViewState. No one knows what the system actually does, so no one knows what's safe to change.

Auto-translators stop at 60%

VB.NET, classic ASP, COM interop, Windows-only dependencies. The last 40% needs hand work, and that's where projects stall for months.

Parity is impossible to prove

The code ships. Tests pass. Something subtle regresses in production. Then the rollback debate begins.

How we do it

Three layers on every .NET migration

Deterministic analysis alone misses intent. AI alone hallucinates. SMEs alone don't scale. We run all three on every job.

Layer 01

Deterministic analysis

Our proprietary engine maps the structure of your .NET codebase. Dependencies, entry points, data flows, dead code, WebForms surface, COM interop, mixed-language references. Output you can trust before making changes.

Dependency map
Portal.WebFormsWebForms
├─ Default.aspx.cs
│    → Services.BillingService
│    → Data.LegacyRepoVB.NET
│    → COM.PaymentBridgeCOM interop
├─ Account/Profile.aspx.cs
└─ Legacy/Reports.aspx.csdead code
3 repos · 1,284 files · 42 cross-language refs
Layer 02

AI for scale

Anchored in static analysis, our AI agents apply verified migration patterns across thousands of files. ASPX to Razor, VB.NET to C#, code-behind to controllers. Each pattern validated once, then scaled.

Migration diff
Account/Profile.aspx → Account/Profile.cshtml
- <asp:Repeater ID="rptOrders" runat="server">
- <ItemTemplate>
- <tr><td><%# Eval("Total") %></td></tr>
- </ItemTemplate>
- </asp:Repeater>
+ @foreach (var order in Model.Orders)
+ {
+ <tr><td>@order.Total</td></tr>
+ }
Pattern: Repeater → @foreach · Applied 247x
Layer 03

SMEs and AI experts

Senior .NET engineers validate the output, add the know-how that only lives in people's heads, and catch the edge cases auto-translators miss. No "AI-best-effort" shipped.

Review annotations
Senior .NET SME
COM.PaymentBridge.dll · line 124

Legacy STA threading assumption. Can't be auto-translated. Replacing with explicit async boundary and adding parity test for concurrent calls.

Senior .NET SME
ViewState handler · Account.aspx

ViewState carries session-scoped pricing rules. Migrating to server-side session, not Razor model binding. Locked.

Engagement model

Your .NET migration, in four scoped stages

Four stages. Fixed price per stage. Commit one step at a time, with validation evidence at every one.

01

Assessment

Snapshot of your .NET stack and modernization fit. Framework version inventory, WebForms surface, third-party library audit. Scoped plan, risks, and success criteria.

What you receive
  • Stack snapshot and inventory
  • Scoped plan
  • Risk register
  • Locked success criteria
02

Specification

Extract the business logic, critical flows, and system behavior teams and agents need to migrate code safely. Documented, queryable, with parity test specs locked.

What you receive
  • Architecture and dependency maps
  • Extracted business logic
  • Documented critical flows
  • Parity test specifications
03

Modernization

Migrate the code to your target .NET stack. Refactor services where the original structure won't survive the move. Visible progress throughout.

What you receive
  • Migrated code on target .NET
  • Refactored services where needed
  • API and integration code
  • Parity validation evidence
04

Enablement

Keep evolving your .NET system independently. Parity test suite, playbooks, training, and knowledge base, handed off to your team.

What you receive
  • Parity test suite
  • Migration playbooks
  • Team training
  • Queryable knowledge base
What you get

A workspace, not a stack of files

Every deliverable lives in one place. Yours to keep, queryable by your tools.

Delivered change

  • Migrated code on target .NET
  • Refactored services where needed
  • API and integration code
  • Cross-platform-ready where applicable

System understanding

  • Architecture and dependency maps
  • Dead-code analysis
  • Extracted business logic
  • Critical flow documentation
  • Queryable by MCP

Enablement assets

  • Parity test suite
  • Migration playbooks
  • Team training
  • Queryable knowledge base

Move .NET forward. With proof.

Get in touch with our team. We'll talk through your codebase, your target stack, and the right path off legacy .NET.

Get in touch