Senior Software Engineer

Topstep is looking for a Senior Software Engineer to own and evolve critical components of their trading platform. In this role, you'll design and build systems that power real-time trading and market data delivery for thousands of active traders, while shaping architectural decisions and ensuring platform scalability.

Responsibilities:

• Design and build services and APIs that power core trading platform capabilities
• Own features end-to-end, from technical design through production deployment, monitoring, and iteration
• Collaborate with product and design to translate user needs into scalable, maintainable technical solutions
• Contribute to system architecture decisions, establishing patterns and practices that other teams can follow
• Write clean, well-tested code with strong focus on reliability, performance, and operational excellence
• Participate in on-call rotations, respond to incidents, and drive continuous improvement of system reliability
• Build and maintain observability into your systems through metrics, logging, and distributed tracing
• Mentor engineers through code reviews, pairing sessions, and sharing knowledge about system design and best practices
• Balance technical debt with feature delivery, making thoughtful trade-offs based on business priorities and technical constraints
• Contribute to engineering culture through documentation, tooling improvements, and process refinements

Requirements:

• 5+ years of software engineering experience building and shipping production systems at scale
• Strong proficiency in C# and .NET ecosystem with experience building production services
• Experience designing service boundaries, API versioning, and event-driven patterns in a microservices or modular architecture
• Solid database experience with PostgreSQL or SQL Server, including schema design, query optimization, and understanding of transactional behavior
• Experience with observability tools and distributed tracing in production environments
• Proven track record of owning production systems including monitoring, debugging, and incident response
• Experience with container technologies (Docker) and cloud platforms (AWS)
• Strong testing mindset with practical experience across unit, integration, and system testing
• Excellent problem-solving skills with ability to debug complex issues across multiple systems
• Clear communication skills with ability to explain technical concepts to both technical and non-technical audiences
• Comfort working in fast-paced environments with evolving priorities and ambiguous requirements
• Kubernetes experience (EKS or equivalent), Helm, or GitOps (ArgoCD) tooling
• Experience with real-time or async messaging (Redis, NATS, Kafka, etc.) OR real-time comms (SignalR/WebSockets)
• Background in high-throughput, low-latency systems or performance optimization
• Distributed tracing and performance tuning in multi-service systems
• Incident leadership (RCA, remediation follow-ups)
• Previous work in compliance-constrained environments
• Previous work in financial services, fintech, or compliance-regulated industries
• Understanding of trading systems, market data, or brokerage operation