CoinRadar

CoinRadar is a crypto portfolio tracking web application with wallet management, transaction history, and swap support.

Stack

• Frontend: React, TypeScript, Redux Toolkit, RTK Query, Tailwind CSS, Chart.js
• Backend: Node.js, Express, TypeScript, PostgreSQL, Prisma ORM, Zod, JWT

Key Features

• Session-based authentication with HttpOnly cookies, access/refresh tokens, and refresh token rotation
• Google OAuth sign-in with callback flow and account linking safeguards
• Wallet management with per-user wallet isolation and access control
• Transaction CRUD with strict chronological validation to prevent invalid historical balances
• Atomic swap execution (single database transaction) with concurrency conflict handling and retry logic
• Deterministic transaction ordering for stable history and chart consistency
• Swap settings per wallet (swapEnabled, stable coin list) enforced on backend
• Integration test suite for auth, chronology, swap atomicity, and concurrency scenarios
• CI pipeline with lint, build, and backend integration tests before deployment