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 optimal performance and reliability • Contribute to technical documentation and best practices REQUIRED QUALIFICATIONS • Bachelor's degree in Computer Science, Software Engineering, or a related field • 7+ years of experience in C# development, with a strong understanding of object-oriented programming principles • Extensive experience with .NET Core and C# • Familiarity with front-end development using modern frameworks, specifically React • Experience with the Microsoft Azure cloud platform, including core services and infrastructure • Experience creating and optimizing CI/CD pipelines, specifically within Azure DevOps • Understanding of software architecture principles and best practices, with proficiency in applying design patterns to solve technical challenges • Proficiency in designing and developing RESTful APIs • Solid understanding of database systems and storage (e.g., SQL Server, PostgreSQL, NoSQL) and ORM frameworks (e.g., Entity Framework) • Demonstrated ability to write clean, testable, and efficient code • Strong problem-solving skills and attention to detail • Excellent communication and collaboration skills • Experience with agentic workflows • Comfortable working with AI and AI-assisted development tools USEFUL QUALIFICATIONS • Contemporary JavaScript / TypeScript (ES2015+), React Hooks, Next.js, Nx • Experience with a message queue such as Kafka or RabbitMQ • Experience writing GraphQL-interfaced services • Experience working with authentication and authorization Salary: $90 – $100 / year Originally posted on Himalayas