Aureus - Real-Time Auction API 🔨

📖 Description

Aureus is a backend REST API system for an online auction platform. It handles user authentication, digital wallets, auction item management, and a real-time bidding system.

This system is designed to safely handle money transactions using an escrow system and provide real-time updates to users without overloading the server.

🎯 Why I Built This

I built this project mainly to learn and practice advanced backend engineering. I wanted to step out of my comfort zone of making simple CRUD applications and learn how to solve real-world problems.

Through this project, I learned how to:

• Build a solid Clean Architecture to make the code easy to maintain.
• Use Dependency Injection (Google Wire) to manage project dependencies.
• Prevent money loss and race conditions using Database Transactions & Pessimistic Locking.
• Build a fast, real-time leaderboard using Redis Sorted Sets (ZSET) and Server-Sent Events (SSE) instead of heavy WebSockets.
• Automate background tasks using Redis Keyspace Notifications and Go Background Workers.

✨ Key Features

• User & Wallet System: Users can register, log in, and have a wallet with Active Balance and Held Balance (Escrow) to make sure bids are safely locked.
• Auction Management: Sellers can create auctions, upload images, and set a start/end time and bid increments.
• Safe Bidding System: When a user places a bid, the system locks the database row, checks the wallet balance, deducts the money, and automatically refunds the previous highest bidder.
• Real-Time Leaderboard: Users can see the top 10 highest bidders live, powered by Redis and Server-Sent Events (SSE).
• Automated Settlement: When an auction time is up, a background worker automatically finalizes the auction and transfers the locked money to the seller.

🛠️ Tech Stack

• Language: Go (Golang)
• Web Framework: Fiber v3
• Database: PostgreSQL
• ORM: GORM
• Payment Gateway: Stripe
• Cache: Redis (go-redis/v9)
• File Storage: SeaweedFS
• Dependency Injection: Google Wire
• JSON Parser: Sonic

🚀 How to Run (Local Development)

1. Clone the repository

git clone https://github.com/Hilaladiii/aureus.git

2. Install The Dependency

go mod tidy

3. Setup Environment Variables

Create a .env file in the root directory and add your configurations (Database, Redis, JWT Secret, etc.).

cp .env.example .env

4. Generate Dependency Injection (Wire)

wire gen ./di

5. Run Docker (DB,S3,Redis)

docker compose up -d

6. Run The Application

If you have Air installed for live-reloading:

air

Otherwise, use the standard Go command:

go run ./cmd/api main.go

Built with ❤️ for learning and exploring Backend Engineering.