Senior Software Developer | HR Technology & Shared Services | Experienced

Susquehanna is seeking a Senior Software Developer to join our HR Technology & Shared Services development team. This team is 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. The team designs and builds internal platforms that integrate with third‑party systems such as UKG, ADP, payroll, and compliance, while also developing custom solutions that cannot be purchased off the shelf. The group operates a dedicated on‑premises hardware environment 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.

• 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: contribute across application, integration, and infrastructure layers
• Security‑Focused Engineering: design systems with strict isolation and reliability for highly sensitive data
• Complex Systems Environment: handle multiple integrations and enterprise‑scale workflows
• Firm‑Wide Impact: build platforms that directly support critical operational functions across Susquehanna

• 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