Onyx

Overview

Onyx is a trading platform with transaction workflows and real-time market data. I structured the Spring Boot backend with Domain-Driven Design, secured its APIs, and built the trade execution interface.

What I built

• Designed the backend with Domain-Driven Design, Spring Boot, Spring Data JPA, Hibernate and PostgreSQL.
• Implemented transaction workflows with Jakarta Bean Validation and declarative transaction management.
• Secured the backend with Spring Security and JWT, tested with JUnit 5.
• Built frontend execution workflows showing real-time market data from WebSocket STOMP streams.

About the visuals

The trading screen shows a live BTC/USDT candlestick chart from Binance Spot data, with intervals from one minute to one day and a switcher for BTC, ETH, BNB, SOL and XRP. The order panel takes long or short orders by lot size, with optional stop-loss and take-profit, and shows the price, commission and margin for the order. Positions and history sit below the chart.

Tools

Spring Boot / JPA / Hibernate / PostgreSQL / WebSocket STOMP

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