Senior Java Backend Engineer – Real-Time Trading Systems

Aquariux Fintech; Singapore; On-site; SGD 120,000 - 180,000; Full time

Job summary

Aquariux Fintech is seeking an experienced Software Engineer to join our core engineering team, building and enhancing a high-performance trading platform with OMS, market data, and exchange connectivity. This role focuses on low-latency systems in a financial trading environment.

You will design and implement backend systems in Java, integrate with exchanges via FIX/REST/WebSocket, and optimize performance in a production setting.

Qualifications

• 5+ years of backend development experience in trading, brokerage, exchange, or crypto platforms.
• Strong proficiency in Java with solid understanding of concurrency and performance considerations.
• Hands-on experience integrating with exchanges or liquidity providers via financial messaging protocols or trading APIs.
• Strong understanding of order lifecycle, execution flow, and exchange connectivity concepts.
• Strong database design and performance tuning experience.
• Comfortable operating in a production trading environment with high reliability expectations.

Responsibilities

• Design and develop high-performance backend trading systems using Java.
• Implement and maintain OMS workflows, including order lifecycle, state management, and idempotency.
• Build and support integrations with exchanges and liquidity providers using industry-standard trading protocols (e.g., FIX, REST, WebSocket, proprietary APIs).
• Develop and maintain real-time market data ingestion and event-driven systems.
• Architect scalable, fault-tolerant distributed systems for high availability.
• Optimize database schema and queries for performance.
• Troubleshoot complex production trading issues and drive root cause analysis.
• Contribute to system architecture and engineering best practices.
• Able to perform support duties as required, including standby for production issues when they arise.

Skills

Java

Concurrency control

Performance optimization

Trading domain knowledge

Problem solving

Tools

FIX protocol

REST

WebSocket

Protobuf

Aeron

gRPC

AWS

Docker

Kubernetes

Job description

Aquariux Fintech is seeking an experienced Software Engineer to join our core engineering team, building and enhancing a high-performance trading platform with OMS, market data, and exchange connectivity. This role focuses on low-latency systems in a financial trading environment.

You will design and implement backend systems in Java, integrate with exchanges via FIX/REST/WebSocket, and optimize performance in a production setting.