Senior Software Developer

Spectrum IT Recruitment; City Of London; On-site; GBP 70,000 - 100,000; Full time

Job summary

Spectrum IT Recruitment is seeking an experienced Senior Software Developer to join a highly technical engineering team delivering software used across trading and quantitative research. The role focuses on C#/.NET and high-performance systems.

You will influence architecture and engineering standards, collaborate with researchers and traders, and work on greenfield and existing platforms to build scalable, reliable software that supports trading strategies and quantitative work.

Qualifications

• 5+ years' commercial software development experience.
• Strong C# and modern .NET development experience.
• Excellent knowledge of OOP, software design principles and architecture.
• Experience designing and building production-grade, scalable applications.
• Strong SQL experience with SQL Server, Oracle or another relational database.
• Experience developing systems where performance, reliability and scalability matter.
• Strong understanding of the full software development lifecycle.
• Excellent analytical and problem-solving skills.
• Strong communication skills and the ability to work effectively with technical and non-technical stakeholders.
• Degree in Computer Science, Mathematics, Physics, Engineering or another relevant technical discipline.

Responsibilities

• Design and build high-performance applications using C# and modern .NET
• Take ownership of complex development projects from initial design through to production
• Influence architecture, technical design and engineering direction
• Build scalable systems supporting automated trading, quantitative research and data-driven applications
• Work directly with researchers and traders to turn complex requirements into robust software solutions
• Design and optimise relational database solutions using SQL Server, Oracle or similar
• Identify and resolve performance bottlenecks across applications and databases
• Develop reliable, maintainable and highly scalable software
• Work with multi-threading, concurrency and asynchronous programming
• Investigate complex technical challenges and deliver long-term solutions
• Contribute to code reviews, automated testing, CI and development tooling
• Mentor other developers and help raise engineering standards across the team

Skills

C#/.NET

Performance optimization

SQL/DB design

Architecture design

Multithreading

Software lifecycle

Education

Degree in Computer Science, Mathematics, Physics, Engineering

Job description

An exciting opportunity for an experienced Senior Software Developer to join a highly technical engineering team building sophisticated software used across trading and quantitative research.

This is a role for a strong C#/.NET engineer who enjoys solving difficult technical problems, working on performance-critical systems and having genuine input into how software is designed and built.

You'll work across both greenfield development and established platforms, creating scalable, reliable and high-performance applications that directly support trading strategies and quantitative research.

As a senior engineer, you'll have significant influence over architecture, technical direction and engineering standards, while collaborating closely with quantitative researchers, traders and other experienced technologists.

What You'll Be Doing

• Design and build high-performance applications using C# and modern .NET

• Take ownership of complex development projects from initial design through to production

• Influence architecture, technical design and engineering direction

• Build scalable systems supporting automated trading, quantitative research and data-driven applications

• Work directly with researchers and traders to turn complex requirements into robust software solutions

• Design and optimise relational database solutions using SQL Server, Oracle or similar

• Identify and resolve performance bottlenecks across applications and databases

• Develop reliable, maintainable and highly scalable software

• Work with multi-threading, concurrency and asynchronous programming

• Investigate complex technical challenges and deliver long-term solutions

• Contribute to code reviews, automated testing, CI and development tooling

• Mentor other developers and help raise engineering standards across the team

What We're Looking For

• 5+ years' commercial software development experience

• Strong C# and modern .NET development experience

• Excellent knowledge of OOP, software design principles and architecture

• Experience designing and building production-grade, scalable applications

• Strong SQL experience with SQL Server, Oracle or another relational database

• Experience developing systems where performance, reliability and scalability matter

• Strong understanding of the full software development lifecycle

• Excellent analytical and problem-solving skills

• Strong communication skills and the ability to work effectively with technical and non-technical stakeholders

• Degree in Computer Science, Mathematics, Physics, Engineering or another relevant technical discipline

Highly Desirable

• Multi-threaded and concurrent application development

• Asynchronous and parallel programming

• Low-latency or high-throughput systems

• TCP/IP, UDP or network programming

• Distributed systems and service-oriented architectures

• Performance profiling and optimisation

• Automated testing and continuous integration

• Windows development technologies

• Git and modern development workflows

• Financial markets, quantitative research or algorithmic trading

• Working alongside quantitative analysts, researchers, traders or data scientists

Why This Role?

This is an opportunity to work on technically challenging software where performance and engineering quality genuinely matter.

You’ll have the freedom to influence architecture and technical decisions, tackle complex engineering problems and see the direct impact of the systems you build in a demanding, data-driven environment.

If you’re an experienced C#/.NET developer looking for more technical ownership and the opportunity to work on sophisticated trading and research technology, this could be an excellent next move.

Spectrum IT Recruitment (South) Limited is acting as an Employment Agency in relation to this vacancy.