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Senior Software Engineer – Low Latency Trading Systems (Core Java)

Chicago, IL | Hybrid (2 Days Onsite REQUIRED) | Long-Term Consulting Opportunity

No Third Parties | No C2C | No Visa Sponsorship

Build Technology That Powers High-Performance Trading

Our client is seeking an experienced Senior Software Engineer with deep expertise building ultra-low latency trading platforms.

This is not a traditional enterprise Java position.

We're looking for engineers who have built and supported mission-critical trading systems where microseconds matter. The ideal candidate understands market data, trading workflows, concurrency, networking, and performance optimization and can immediately contribute within a highly technical engineering team.

Candidates without recent low latency trading platform experience will not be considered.

What You'll Do

• Design and develop ultra-low latency Java applications supporting electronic trading platforms
• Build and optimize backend trading services and distributed microservices
• Analyze and optimize application performance for high-throughput, low-latency environments
• Troubleshoot complex production issues and performance bottlenecks
• Optimize algorithms, memory utilization, JVM tuning, and threading models
• Work closely with senior engineers on architecture, code reviews, and system optimization
• Support production releases, security updates, and platform enhancements
• Utilize low-level diagnostic tools to analyze system behavior and optimize performance
• Develop clean, scalable, maintainable Java applications supporting mission-critical trading systems

Required Experience

• 8+ years of Core Java software engineering
• Recent experience developing low latency trading platforms
• Experience supporting electronic trading or capital markets systems
• Strong understanding of trading workflows and market data processing
• Experience building backend trading applications—not database-centric applications
• Strong understanding of distributed microservices architecture
• Advanced knowledge of multithreading, concurrency, synchronization, shared memory, and asynchronous programming
• Strong understanding of algorithms and data structures
• Experience optimizing high-performance Java applications
• Experience working with TCP/IP and UDP networking
• Strong Linux experience
• Self-starter capable of contributing immediately with minimal supervision

Technical Skills

Strong experience with:

• Core Java
• Low Latency Systems
• Multithreading
• Concurrent Data Structures
• Shared Memory
• JNI
• Java NIO
• TCP / UDP Networking
• JVM Performance Tuning
• Garbage Collection Optimization
• Linux
• Linux Kernel Performance
• Microservices Architecture
• Performance Profiling
• Production Support

Preferred experience with:

• Solarflare Networking
• EF_VI
• Onload APIs
• Thread Pinning
• NUMA Architecture
• CPU Cache Optimization
• Interrupt Handling
• Packet Capture
• Hardware Performance Counters

Trading Domain Experience Required

Candidates should have experience working with one or more of the following:

• Electronic Trading Platforms
• Matching Engines
• Order Book Management
• Market Data Processing
• Trading Logic
• Credit Checks
• Order Routing
• Market Connectivity
• Exchange Connectivity
• Capital Markets Technology

What We're Looking For

We're looking for an engineer who understands the unique challenges of building software where performance, determinism, and reliability are critical.

This is an opportunity to work on highly sophisticated trading technology alongside experienced engineers solving complex performance and scalability challenges.

Important Requirements

• Hybrid schedule (2 days per week in the office)
• Chicago or New York
• Long-term consulting opportunity
• Must have recent low latency trading platform experience
• Must have financial services or capital markets experience
• No Third Parties
• No Corp-to-Corp (C2C)
• No Visa Sponsorship

We care about the success of each member of out team! We strive for long lasting partnerships where you can grow and expand your career.