Why it exists
A client app that can trigger paid operations needs clear rules for authentication, ownership, replay, and failure recovery.
Portfolio / CASE STUDY
Private backend project
Nifty Outfit Nook Backend.
The backend for a native wardrobe app, with a versioned API contract, authenticated device requests, and safeguards around paid image operations.
MY ROLE
Independent backend and security engineering
What I built
I built the backend around a versioned contract and wrote tests for request verification, authorization, credit accounting, and operational recovery.
Project in view
Engineering decisions
Use a shared contract
Versioned schemas and examples let the mobile client and backend check the same request and response shapes.
Verify identity and ownership
The authorization suite exercises account boundaries and the device attestation tests verify how signed requests are handled.
Protect credits and recovery
Tests cover duplicate transaction claims and attempts to reuse a transaction across accounts. Backup and restore checks exercise recovery separately.
Capabilities in practice
- API contract design
- Authorization and replay protection
- Idempotent credits
- Backup and recovery
Status & scope
Private implementation. I can discuss the architecture and test strategy on request.
Private repository nifty-outfit-nook-backend