Senior C#/.NET Developer - WPF & Excel Add-ins

Energy Cognito LLC; Austin (TX); On-site; USD 120,000 - 160,000; Full time

Job summary

Energy Cognito LLC is seeking a Senior C# Developer to design and maintain an enterprise energy trading and risk management platform. You will work across backend services, WPF desktop applications, and Excel add-ins built with MS .Net to deliver robust, scalable solutions.

You will collaborate with quantitative analysts and business users, tackle legacy and modern codebases, and help implement APIs, reporting, and data management on SQL Server—driving reliability and automated testing in a

Qualifications

• 5+ years of professional C#/.NET development experience.
• Strong experience with WPF, MVVM, and desktop application development.
• Strong SQL Server and relational database skills.
• Experience developing Excel add-ins, preferably with Excel-DNA.
• Experience designing APIs, services, and reusable components.
• Strong debugging, testing, and problem-solving skills.
• Ability to work across legacy and modern codebases.
• Experience with financial, trading, energy, or calculation-intensive systems preferred.
• Excellent written communication and ability to work with partially defined requirements.

Responsibilities

• Design and develop C#/.NET backend and frontend functionality.
• Maintain and improve WPF user interfaces and workflows.
• Develop Excel add-ins, functions, and integration tools using MS .Net.
• Implement trade capture, valuation, reporting, and data-management features.
• Work with SQL Server databases and complex financial datasets.
• Troubleshoot production issues and improve application reliability.
• Create automated tests and participate in code reviews.
• Work with business users and quantitative analysts to clarify requirements.

Skills

C#/.NET

WPF MVVM

SQL Server

Excel add-ins

Excel-DNA

API design

Testing & debugging

Legacy codebases

Financial systems

Education

Bachelor's degree in Computer Science or related

Tools

Excel-DNA

Job description

Energy Cognito LLC is seeking a Senior C# Developer to design and maintain an enterprise energy trading and risk management platform. You will work across backend services, WPF desktop applications, and Excel add-ins built with MS .Net to deliver robust, scalable solutions.

You will collaborate with quantitative analysts and business users, tackle legacy and modern codebases, and help implement APIs, reporting, and data management on SQL Server—driving reliability and automated testing in a