C# Software Engineer

C#/.NET Software Engineer – Bala Cynwyd, PA / New York, NY

Radley James is working with a leading quantitative trading firm that is looking to hire a C#/.NET Software Engineer to join its technology organisation.

This is an opportunity to work on business-critical applications in a fast-paced environment where technology plays a central role in the firm's success. You'll have ownership across the full software development lifecycle, working on scalable systems, data-driven applications, and tools used across the business.

Responsibilities

• Design, develop, and maintain software applications using C#/.NET.
• Build scalable, reliable, and high-performance systems.
• Develop tools, applications, and data solutions that support business-critical workflows.
• Collaborate with stakeholders to gather requirements and deliver impactful solutions.
• Take ownership of projects throughout the full software development lifecycle, from design through to production support.
• Contribute to system architecture, performance improvements, and long-term platform evolution.

Requirements

• 4+ years of commercial software development experience.
• Strong experience with C#/.NET.
• Engineers with a strong Java background who are interested in transitioning to C# will also be considered.
• Solid understanding of software engineering principles, system design, and problem solving.
• Experience building scalable, distributed, or business-critical applications.
• Familiarity with modern development practices, including source control and CI/CD workflows.
• Strong communication skills and a collaborative approach to development.
• BS or MS in Computer Science, Computer Engineering, or a related discipline.

Nice to Have

• Experience with Python, JavaScript/TypeScript, or React.
• Experience working with large datasets or data-intensive applications.
• Linux development experience.
• Exposure to cloud technologies, distributed systems, or performance optimisation.
• Experience within financial services, trading, or other high-performance environments.

What's on Offer

• Opportunity to work at one of the world's leading quantitative trading firms.
• Challenging technical problems and significant ownership.
• Modern technology stack and highly collaborative engineering culture.
• Competitive compensation package and visa sponsorship available.
• Opportunities available in Bala Cynwyd (Philadelphia Area) and New York City.