Full-stack
INOVIT Dealer Portal
Solo-built a full replacement for a legacy C#/.NET 4.8 dealer portal — both systems running on the same production database, processing live orders, with zero downtime and zero schema changes.
React 19TypeScriptDjango 5DRFSQL ServerAnt Design 6Vite 8DockerAWS
My Role
What I ownedEverything. Architecture design, frontend, backend, database mapping, CI/CD pipelines, Docker infrastructure, monitoring, and production deployment. Solo developer on a greenfield rewrite.
The hard partThe legacy .NET ERP processes live orders daily — it could not go offline, and its database schema could not change. I had to build a new system that reads and writes the same tables simultaneously, without the old system ever noticing.
At a Glance
0
Downtime
0
Schema Changes
49
API Endpoints
4
Regions
44
ORM Models
1
Developer
Tech Stack
Frontend
React · TypeScript · Vite · Ant Design
Backend
Django · DRF · Python · Gunicorn
Database
SQL Server 2025 — 4 regional databases, 42 unmanaged models via mssql-django
Infra
AWS Lightsail · Docker · Caddy · GitHub Actions · S3 · Lambda · SES (SMTP)
Testing
Vitest · Playwright · pytest · OpenAPI drift checks in CI
Two Systems, One Database
The new Django API and the legacy .NET ERP read and write to the same SQL Server tables at the same time. Django maps 42 legacy tables with managed = False — the ORM works normally, but Django never tries to create, alter, or migrate those tables. Two new managed tables were added for asset categorization features the ERP doesn't touch. Both systems process orders in parallel without awareness of each other.
New System
React SPAAnt Design · lazy-loaded routes
CaddyTLS · reverse proxy · static files
Django APIGunicorn · JWT auth · region routing
Shared Infrastructure
SQL Server 2025AU · UK · US · Demo — both systems read/write
Legacy .NET ERPStill running, still processing orders
Supporting Services
S3 + CDNDual-bucket assets · WebP thumbnails via Lambda
MonitoringUptime Kuma · Dozzle · Beszel
One Codebase, Four Databases
Dealers in Australia, UK, and US each have their own SQL Server database with regional pricing, inventory, and orders. Rather than deploying a separate backend per region, a single Django instance routes every ORM query to the correct database based on the JWT region claim — through a custom middleware + database router pair.
Dealer logs in
JWT carries region claim
Middleware
Extracts region per request
DB Router
Routes ORM to correct DB
AU / UK / US / Demo
Isolated data per region
Trade-offs
OpenAPI as the contract boundary
Three repos, one developer — the frontend had to break loudly when the backend API changed. Backend CI generates the OpenAPI spec, dispatches it to the frontend repo, and auto-generates TypeScript types. Contract drift is a build failure, not a silent runtime bug discovered by a dealer.
Auth caching across AWS instances
The SQL Server lives on a separate AWS instance. Every auth lookup crosses the network. A 5-minute LocMemCache on the API server eliminates that round-trip for repeat requests — short enough that ERP-side user changes (disabling an account, changing permissions) still propagate within minutes.
2 MB bundle budget
A hard CI gate at 2 MB catches size regressions before they merge — keeps the app fast without relying on manual review to spot bloated imports.
Build-time architecture enforcement
Nine feature modules can turn into a dependency web fast. ESLint rules encode the dependency direction (types → services → hooks → features) and forbid cross-feature imports. Architectural violations fail the build — they don't survive as "we'll fix it later" TODOs.