Work · Kartega Yazılım

OpinTag

Digital identity and lifecycle platform for tech assets

Overview

OpinTag gives phones, computers, consoles and electric vehicles a digital identity. Individuals and companies register their assets, print a QR label, keep service and damage history, transfer ownership and report lost or stolen devices. Companies can also track who holds which device.

The problem

Proof of ownership, service history and lost/stolen status get lost, so second-hand trust is low — and companies track device custody in spreadsheets.

Key features

• Asset registration by IMEI, serial number or VIN with duplicate checks and camera barcode/QR scanning
• Printable QR label that opens a public profile with masked details
• Ownership transfer with automatic approval after 14 days
• Lost/stolen cases with a public directory and anonymous contact
• Damage records, service records and valuation reports
• Marketplace listings with buyer messages and view statistics
• EV route and charging planner, and a map of authorised service points
• Corporate tools: team roles, custodian assignment and audit; subscriptions with 3D Secure checkout

Architecture

• .NET 8 backend with separate admin and tenant API hosts, PostgreSQL and Redis
• Row-level multi-tenancy: every record is isolated by (TenantID, ID), with tenant members and invitations
• KVKK-compliant audit logging for every write operation and masking of personal data on public pages
• Pluggable EV charging-station sync from several data providers
• Next.js frontend with maps, charts and in-browser barcode scanning

Technical challenges

• Protecting personal data under KVKK while still offering a public QR profile and lost-device directory
• Tenant isolation for corporate customers sharing one platform
• Normalising charging-station data from providers with different formats

Tech stack