Skip to main content
Vibgrate Graph: over 27% fewer tokens in our benchmark
Blueprint

Visual Basic / WinForms to Web Application Blueprint

Modernize VB6 or .NET WinForms desktop apps into a browser-based web application by extracting business logic behind an ASP.NET Core API and rebuilding the UI in React or Blazor, migrating screen by screen.

From
Winforms
To
Web App
Difficulty
Advanced
Duration
26 weeks
Team Size
medium

What and Why

Visual Basic 6 is long out of support, and even .NET Framework WinForms apps are hard to deploy (per-machine installs, DLL versioning) and impossible to use on mobile or thin clients. Modernizing to a web application centralizes deployment, enables remote access, and opens the door to cloud hosting. The strategy: extract business logic behind an API, then rebuild the UI in the browser.

Phases

Assessment. Inventory forms, controls, event handlers, COM/ActiveX dependencies (for VB6), database access, and embedded business rules. Separate UI logic from domain logic. For VB6, decide whether to first bridge to .NET via interop or rewrite directly.

API extraction. Reimplement business and data-access logic as a clean .NET (ASP.NET Core) service with an OpenAPI-defined REST API and hexagonal boundaries. Where logic is sound, port it; where it is tangled in form events, refactor as you extract.

UI rebuild. Build a SPA (React or Blazor) with a component library and accessible data grids matching desktop power-user expectations. Replace ActiveX grids and report controls with web equivalents. Migrate screen by screen behind a launcher.

Data migration. Keep the existing database (often SQL Server or Access) as the source of truth initially; migrate Access to SQL Server/PostgreSQL where needed. Validate via reconciliation.

Cutover. Roll out per module/user group, run desktop and web in parallel, then retire the desktop installer and ActiveX dependencies.

Key Risks and Mitigations

  • Lost rules buried in event handlers: Inventory exhaustively and cover with tests during extraction.
  • ActiveX/COM dependencies: Find web-native replacements early; some custom controls need rework.
  • User productivity: Preserve keyboard shortcuts and bulk entry; involve power users.

Recommended Tooling

ASP.NET Core, OpenAPI, React or Blazor, an accessible data-grid library, OAuth2/OIDC, SQL Server/PostgreSQL, and reconciliation tests. Use feature flags and a launcher to migrate incrementally.

Success Metrics

Centralized deployment (higher deployment frequency), improved maintainability, broader device access, and higher user satisfaction.

Prerequisites

Access to source and database, .NET expertise, engaged users, and a phased rollout. Defer database migration where it adds risk; modernize the UI and logic first.

Tags

frontendlegacy migrationmodernizationcsharpapi designstrangler fig
Vibgrate CLI

See a real scan run

A replay of the actual CLI running against our test repositories — live progress, real findings, a genuine DriftScore. Nothing executes in your browser.

Replay
demo@vibgrate — bash
❯ npx @vibgrate/cli scan
 
╭──────────────────────────────────────────╮
│ Vibgrate Drift Report │
╰──────────────────────────────────────────╯
 
── node-turborepo (node) .
Runtime: >=18.0.0 (6 majors behind)
Frameworks:
Turbo: 1.13.4 → 2.10.12 (1 behind)
TypeScript: 5.9.3 → 7.0.2 (2 behind)
Dependencies:
1 current 1 1-behind 3 2+ behind 1 unknown
 
── @repo/admin (node) apps/admin
Frameworks:
TanStack Query: 5.102.5 → 5.102.5 (current)
React: 18.3.1 → 19.2.8 (1 behind)
React DOM: 18.3.1 → 19.2.8 (1 behind)
TypeScript: 5.9.3 → 7.0.2 (2 behind)
Vite: 5.4.21 → 8.2.2 (3 behind)
Dependencies:
3 current 9 1-behind 3 2+ behind 4 unknown
 
── @repo/api (node) apps/api
Frameworks:
Express: 4.22.2 → 5.2.1 (1 behind)
TypeScript: 5.9.3 → 7.0.2 (2 behind)
Vitest: 1.6.1 → 4.1.11 (3 behind)
Dependencies:
7 current 5 1-behind 3 2+ behind 4 unknown
 
── @repo/web (node) apps/web
Frameworks:
Next.js: 14.2.35 → 16.3.3 (2 behind)
React: 18.3.1 → 19.2.8 (1 behind)
React DOM: 18.3.1 → 19.2.8 (1 behind)
TypeScript: 5.9.3 → 7.0.2 (2 behind)
Dependencies:
2 current 6 1-behind 3 2+ behind 5 unknown
 
── @repo/config (node) packages/config
Frameworks:
TypeScript: 5.9.3 → 7.0.2 (2 behind)
Dependencies:
2 current 2 1-behind 5 2+ behind 0 unknown
 
── @repo/database (node) packages/database
Frameworks:
Prisma: 5.22.0 → 7.10.0 (2 behind)
TypeScript: 5.9.3 → 7.0.2 (2 behind)
Dependencies:
1 current 0 1-behind 3 2+ behind 1 unknown
 
── @repo/types (node) packages/types
Frameworks:
TypeScript: 5.9.3 → 7.0.2 (2 behind)
Dependencies:
0 current 0 1-behind 1 2+ behind 1 unknown
 
── @repo/ui (node) packages/ui
Frameworks:
React: 18.3.1 → 19.2.8 (1 behind)
TypeScript: 5.9.3 → 7.0.2 (2 behind)
React: 18.3.1 → 19.2.8 (1 behind)
Dependencies:
1 current 4 1-behind 1 2+ behind 1 unknown
 
── @repo/utils (node) packages/utils
Frameworks:
TypeScript: 5.9.3 → 7.0.2 (2 behind)
Vitest: 1.6.1 → 4.1.11 (3 behind)
Dependencies:
0 current 1 1-behind 2 2+ behind 1 unknown
 
Tech Stack
Frontend: React, React DOM
Meta-frameworks: Next.js
Bundlers: tsx, Turbo, Vite
CSS / UI: Autoprefixer, PostCSS, Tailwind CSS
Backend: Express
ORM / Database: Prisma, Prisma Client
Testing: Vitest
Lint & Format: ESLint, ESLint Prettier, ESLint React, Prettier, typescript-eslint
 
Services & Integrations
Auth: JWT 9.0.3
Databases: Prisma 5.22.0
 
TypeScript
v5.3.3 · strict ✔ · MIXED · target: ES2022
 
Build & Deploy
Package Managers: pnpm
Monorepo: npm-workspaces, pnpm-workspaces, turbo
 
Product Purpose Signals
Frameworks: react, nextjs
Evidence: 177
Top Signals:
- [heading] Dashboard (apps/admin/src/pages/Dashboard.tsx)
- [title] Revenue Overview (apps/admin/src/pages/Dashboard.tsx)
- [copy] workspace:* (packages/ui/package.json)
- [copy] ./dist (packages/ui/tsconfig.json)
- [copy] ./src/index.ts (packages/ui/package.json)
- [copy] @repo/config/tsconfig-base.json (packages/ui/tsconfig.json)
- [copy] @repo/ui (packages/ui/package.json)
- [copy] #3b82f6 (apps/admin/src/pages/Dashboard.tsx)
Unknowns:
- No pricing or billing evidence found.
- No integrations/connectors evidence found.
- No route structure evidence found.
 
Security Posture
Lockfile ✖ · .env ✔ · node_modules ✔
 
Platform
Native modules: turbo
 
Code Quality
Files: 36 · Functions: 183 · Avg complexity: 2.62 · Avg length: 21.13 lines
Max nesting: 2 · Circular deps: 0 · Dead code: 0%
God files: apps/admin/src/pages/Products (448 lines)
 
Database Schema
postgresql · 8 models · 1 enum
Models: Address, CartItem, Category, Order, OrderItem (+3 more)
 
Findings (16 errors, 11 warnings)
✖ Node.js runtime ">=18.0.0" reached end-of-life on 2025-04-30 (latest: 24.0.0).
vibgrate/runtime-eol in .
⚠ TypeScript is 2 major versions behind (current: 5.9.3, latest: 7.0.2).
vibgrate/framework-major-lag in .
✖ 60% of dependencies are 2+ major versions behind in node-turborepo.
vibgrate/dependency-rot in .
✖ @types/node is 6 major versions behind (spec: ^20.11.0, latest: 26.3.0).
vibgrate/dependency-major-lag in .
⚠ TypeScript is 2 major versions behind (current: 5.9.3, latest: 7.0.2).
vibgrate/framework-major-lag in apps/admin
✖ Vite is 3 major versions behind (current: 5.4.21, latest: 8.2.2).
vibgrate/framework-major-lag in apps/admin
✖ vite is 3 major versions behind (spec: ^5.0.12, latest: 8.2.2).
vibgrate/dependency-major-lag in apps/admin
⚠ TypeScript is 2 major versions behind (current: 5.9.3, latest: 7.0.2).
vibgrate/framework-major-lag in apps/api
✖ Vitest is 3 major versions behind (current: 1.6.1, latest: 4.1.11).
vibgrate/framework-major-lag in apps/api
✖ @types/node is 6 major versions behind (spec: ^20.11.0, latest: 26.3.0).
vibgrate/dependency-major-lag in apps/api
✖ vitest is 3 major versions behind (spec: ^1.2.1, latest: 4.1.11).
vibgrate/dependency-major-lag in apps/api
⚠ Next.js is 2 major versions behind (current: 14.2.35, latest: 16.3.3).
vibgrate/framework-major-lag in apps/web
⚠ TypeScript is 2 major versions behind (current: 5.9.3, latest: 7.0.2).
vibgrate/framework-major-lag in apps/web
✖ @types/node is 6 major versions behind (spec: ^20.11.0, latest: 26.3.0).
vibgrate/dependency-major-lag in apps/web
⚠ TypeScript is 2 major versions behind (current: 5.9.3, latest: 7.0.2).
vibgrate/framework-major-lag in packages/config
✖ 56% of dependencies are 2+ major versions behind in @repo/config.
vibgrate/dependency-rot in packages/config
✖ eslint-plugin-react-hooks is 3 major versions behind (spec: ^4.6.0, latest: 7.1.1).
vibgrate/dependency-major-lag in packages/config
⚠ Prisma is 2 major versions behind (current: 5.22.0, latest: 7.10.0).
vibgrate/framework-major-lag in packages/database
⚠ TypeScript is 2 major versions behind (current: 5.9.3, latest: 7.0.2).
vibgrate/framework-major-lag in packages/database
✖ 75% of dependencies are 2+ major versions behind in @repo/database.
vibgrate/dependency-rot in packages/database
⚠ TypeScript is 2 major versions behind (current: 5.9.3, latest: 7.0.2).
vibgrate/framework-major-lag in packages/types
✖ 100% of dependencies are 2+ major versions behind in @repo/types.
vibgrate/dependency-rot in packages/types
⚠ TypeScript is 2 major versions behind (current: 5.9.3, latest: 7.0.2).
vibgrate/framework-major-lag in packages/ui
⚠ TypeScript is 2 major versions behind (current: 5.9.3, latest: 7.0.2).
vibgrate/framework-major-lag in packages/utils
✖ Vitest is 3 major versions behind (current: 1.6.1, latest: 4.1.11).
vibgrate/framework-major-lag in packages/utils
✖ 67% of dependencies are 2+ major versions behind in @repo/utils.
vibgrate/dependency-rot in packages/utils
✖ vitest is 3 major versions behind (spec: ^1.2.1, latest: 4.1.11).
vibgrate/dependency-major-lag in packages/utils
 
╭──────────────────────────────────────────╮
│ Top Priority Actions │
╰──────────────────────────────────────────╯
 
1. Upgrade EOL runtime in node-turborepo
End-of-life runtimes no longer receive security patches and block ecosystem upgrades.
./.
>=18.0.0 → 24.0.0 (6 majors behind)
Impact: −10 drift points (runtime & EOL)
 
2. Fix security posture: no lockfile found
Without a lockfile, installs are non-deterministic. Run the install command to generate one and commit it.
./
Missing: package-lock.json, pnpm-lock.yaml, or yarn.lock
 
3. Upgrade Vite 5.4.21 → 8.2.2 in @repo/admin (+2 more)
3 major versions behind. Major framework drift increases breaking change risk and blocks access to security fixes and performance improvements.
./apps/admin
Vite: 5.4.21 → 8.2.2 (3 majors behind)
./apps/api
Vitest: 1.6.1 → 4.1.11 (3 majors behind)
./packages/utils
Vitest: 1.6.1 → 4.1.11 (3 majors behind)
Impact: −5–15 drift points
 
4. Reduce dependency rot in @repo/types (100% severely outdated)
1 of 1 dependencies are 2+ majors behind. Run `npm outdated` and prioritise packages with known CVEs or breaking API changes.
./packages/types
typescript: 5.9.3 → 7.0.2 (2 majors behind)
Impact: −5–10 drift points
 
5. Reduce dependency rot in @repo/database (75% severely outdated)
3 of 4 dependencies are 2+ majors behind. Run `npm outdated` and prioritise packages with known CVEs or breaking API changes.
./packages/database
@prisma/client: 5.22.0 → 7.10.0 (2 majors behind)
prisma: 5.22.0 → 7.10.0 (2 majors behind)
typescript: 5.9.3 → 7.0.2 (2 majors behind)
Impact: −5–10 drift points
 
╭──────────────────────────────────────────╮
│ Architecture Layers │
╰──────────────────────────────────────────╯
 
Archetype: nextjs (80% confidence)
Files classified: 24 (11 unclassified)
Folders classified: 8
apps/admin/src presentation 100% 4 files
apps/admin/src/pages presentation 100% 2 files
apps/api/src/middleware middleware 100% 2 files
apps/api/src/routes routing 100% 2 files
apps/web/src/app presentation 100% 4 files
apps/web/src/app/products presentation 100% 2 files
apps/web/src/app/products/[id] presentation 100% 1 file
packages/ui/src presentation 100% 6 files
Unclassified source (sample): 11
 
presentation 15 files drift ████████████████████ 100 risk high
routing 4 files drift ████████████████████ 100 risk high
middleware 2 files drift ███████▍░░░░░░░░░░░░ 37 risk moderate
config 2 files drift ░░░░░░░░░░░░░░░░░░░░ 0 risk none
shared 1 file drift ████████████████████ 100 risk high
 
╭──────────────────────────────────────────╮
│ DriftScore Summary │
╰──────────────────────────────────────────╯
 
DriftScore: 66/100
Risk Level: HIGH
Projects: 9
Classified: 8 nano · 1 micro · 0 small · 0 standard
Billable: 0.42 · 9 detected → 0.42 billable projects (micro-project pricing)
0.1 micro · 0.32 nano
These fractions add up across repositories, then round down to whole billable projects.
 
Score Breakdown
Runtime: ████████████████████ 100
Frameworks: █████████▏░░░░░░░░░░ 46
Dependencies: ██████▏░░░░░░░░░░░░░ 31
EOL Risk: ████████████████████ 100
 
Scanned at 2026-08-26T09:08:28.481Z · 7.1s · 286 files scanned · 56 workspace files · 27 dirs
❯
Press Run to start.
Explore the Vibgrate CLI