Senior C++/C# Performance Engineer for RealTime Market Data

United States Digital Space LLC; Greater London; Remote; GBP 105,000 - 150,000; Full time

Job summary

United States Digital Space LLC in London is seeking a midlevel to senior IC to join our core engineering team. You will own and evolve our high-performance C# client library while collaborating with the core engineering group on low-latency C++ services.

The role focuses on writing parsers and feed handlers for direct market data, optimizing throughput to multi-million messages per second and building petabyte-scale data tools, with emphasis on reliability, testing, and developer-friendly APIs.

Qualifications

• 5+ years of full-time software engineering experience, preferably at a trading firm, tech company, or high-growth startup.
• Strong proficiency in both C++ and C#.
• Experience designing APIs with intuitive, developer-friendly interfaces.

Responsibilities

• Own and maintain our C# client library, ensuring it is robust, well-tested, and easy for external users to integrate with.
• Design, develop, and maintain high-performance server applications in C++.
• Write message parsers and feed handlers for direct market data feeds from trading venues.
• Optimize existing codebase for high throughput (millions of messages per second, up to 40+ gigabits) and low latency (nanoseconds).
• Implement tools and libraries for petabyte-scale data processing and analysis.
• Collaborate with the systems team to implement best practices for build, deployment, CI/CD.
• Implement monitoring and improve application uptime.
• Ensure smooth feature rollouts and updates.

Skills

C++

C#

Java

Job description

United States Digital Space LLC in London is seeking a midlevel to senior IC to join our core engineering team. You will own and evolve our high-performance C# client library while collaborating with the core engineering group on low-latency C++ services.

The role focuses on writing parsers and feed handlers for direct market data, optimizing throughput to multi-million messages per second and building petabyte-scale data tools, with emphasis on reliability, testing, and developer-friendly APIs.