Senior Software Engineer (.NET/C#/Azure)

OVERVIEW OnTrac is seeking a Senior Software Engineer (.NET / C# / Azure) to join a contractor program supporting a large wholesale digital-marketplace customer. The customer is rebuilding its digital auction platform and decoupling it from a legacy auction management system, standing up a new, independent, modern auction backend purpose-built for a digital-first marketplace. Phase 1 delivers the core platform: inventory management, financial transactions, and customer management.

The initiative is broad in scope and spans four or more teams. This role is ideal for a hands-on senior engineer who writes production C# on .NET Core, is comfortable on Azure and Azure DevOps, and can collaborate across teams to turn business requirements into maintainable, scalable software. ENGAGEMENT • Expected start: ASAP • Location: United States, fully remote RESPONSIBILITIES • Implement core features for the new platform, which could include inventory management, financial transactions, and customer management • Collaborate closely with team members, other teams, and product managers to translate business requirements into technical solutions • Develop high-quality, maintainable, and efficient C# code within an agile development environment • Design and implement efficient data models and database interactions • Integrate the new system with existing platforms and third-party systems • Conduct code reviews and provide constructive feedback to peers • Troubleshoot and debug issues, ensuring o