Senior Staff Engineer

Overview

Power Global Markets with Code - Join StoneX

At StoneX, we don't just build software - we architect the infrastructure behind global trading and financial innovation. With over 4,300 employees and clients in 180+ countries, we're a Fortune 100, Nasdaq-listed fintech powerhouse that connects retail and institutional investors to the world's markets.

We're growing our API Engineering team - and we're looking for sharp, collaborative engineers who love solving real-world problems at scale.

Responsibilities

About the Role (Position Purpose)

This role is ideal for an experienced .NET engineer who thrives on ownership, having knowledge and experience in using .NET ecosystem, knowing the newest trends, be up to date with the newest .NET technology, and wants to work on robust APIs that power real trading - including authentication, pricing, order handling, and more, high loads, low latency systems.

You'll be an essential part of a highly skilled product team, collaborating with other engineers, tech leads, and QAs to build scalable, high-performing systems used by thousands of clients.

Tech Stack You'll Work With

• Languages & Frameworks: C#, .NET Core, ASP.NET Core
• Architecture: Microservices, Event-driven (Kafka, AMQ), CQRS
• Cloud & Infra: Azure, Kubernetes, Docker, Rancher, TeamCity, Octopus, Grafana, Grafana
• Databases: MS SQL Server (T-SQL), NoSQL, Postgres
• Tooling: GitHub , Visual Studio/Rider, ReSharper
• AI Tools: MS Copilot, GitHub Copilot, ChatGPT
  
  

Primary duties will include :

• Design and develop low-latency solutions using the latest .NET technologies. Build performant, scalable backend services from scratch, or improve existing ones
• Tackle live production challenges
• Participate in code reviews, design sessions, and agile ceremonies
• Work closely with team leads and stakeholders and other teams across company
• Continuously explore and evaluate new technologies that could enhance the platform
  
  

Qualifications

What We're Looking For

• 3–5+ years of experience in backend .NET/C# development
• Solid grasp of .NET Core, APIs (high-load - a plus) multithreading and performance
• Experience with messaging systems like ActiveMQ, Kafka
• Hands on experience with Kubernetes
• Experience with financial systems or real-time data Big bonus.
• Good SQL knowledge; NoSQL is a plus
• Strong communication skills and the ability to collaborate across teams
• A growth mindset and eagerness to stay current with industry trends
  
  

Education

• Bachelor's degree in Computer Science, Software Engineering, or equivalent experience
• Having certifications in related areas is a plus
  
  

What We Offer

• Work on mission-critical systems used globally
• Ownership, and room to grow technically and personally
• A collaborative team of talented engineers
• Hybrid work flexibility
• Office perks, private parking, and professional development support