Overview

Susquehanna is seeking a Senior Software Developer to join our HR Technology & Shared Services development team, a specialized engineering group responsible for building secure, scalable, and business-critical platforms that support enterprise functions across the firm.

This is a full-stack engineering role within a high-performance quantitative trading firm, where precision, security, and craftsmanship matter. The team designs and builds internal platforms that integrate with best-in-class third-party systems (UKG, ADP, payroll, compliance, and others) while also developing custom solutions that cannot be purchased off the shelf.

The group operates a dedicated on-premises hardware environment to support systems responsible for highly sensitive firm data. As a Senior Developer, you will work end-to-end — from architecture and application design to deployment and operational support — in collaboration with experienced engineers and cross-functional stakeholders.

 

What You’ll Do

• Build solutions leveraging LLMs running on our on-prem GPU infrastructure
• Design and build secure, scalable applications supporting critical business functions
• Architect and maintain integrations across enterprise systems (HR, payroll, compliance, compensation)
• Build internal tools and platforms where commercial solutions do not meet business needs
• Work across the full SDLC: architecture → development → deployment → monitoring
• Contribute to a dedicated on-premises infrastructure environment
• Collaborate with engineers, analysts, and system owners to translate complex requirements into production-ready systems

 

End-to-End Ownership  Engineers contribute across application, integration, and infrastructure layers.

Security-Focused Engineering  Systems support highly sensitive data (e.g., compensation, performance, firm-wide workflows) and are designed with strict isolation and reliability standards.

Complex Systems Environment  Multiple integrations, diverse data flows, and enterprise-scale workflows require thoughtful system design and strong engineering fundamentals.

Firm-Wide Impact  The platforms built by this team directly support critical operational functions across Susquehanna.

What we’re looking for

• Bachelor’s degree in Computer Science, Engineering, Mathematics or a related discipline. Relevant experience can be substituted for education.
• 10+ years of hands-on software development experience
• Strong proficiency in C# or Java
• Experience with SQL, Web Development, and API-driven architectures
• Experience working with AI-assisted tooling (Copilot, Cursor, Claude Code, etc.)
• Interest in understanding systems beyond code — including deployment, data flow, and reliability
• Strong collaboration and communication skills across technical and non-technical teams
• Any experience deploying solutions using AI for inference is a plus

About Susquehanna

Susquehanna is a global quantitative trading firm powered by scientific rigor, curiosity, and innovation. Our culture is intellectually driven and highly collaborative, bringing together researchers, engineers, and traders to design and deploy impactful strategies in our systematic trading environment. To meet the unique challenges of global markets, Susquehanna applies machine learning and advanced quantitative research to vast datasets in order to uncover actionable insights and build effective strategies. By uniting deep market expertise with cutting-edge technology, we excel in solving complex problems and pushing boundaries together.

What we do

We are experts in trading essentially all listed financial products and asset classes, with a focus on derivatives trading. Through market making and market taking, we handle millions of trading transactions around the world every day, providing liquidity and ensuring competitive prices for buyers and sellers. While our presence in the market is broad, our trading desks are highly specialized, allowing for a deep understanding of unique drivers of each asset class.

 

If you're a recruiting agency and want to partner with us, please reach out to recruiting@sig.com. Any resume or referral submitted in the absence of a signed agreement will not be eligible for an agency fee.

 

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