Senior Software Developer - C#

Senior Software Developer

Location: Twin Cities, MN (Hybrid / On-site preferred) | Employment Type: Full-Time | Experience Level: Mid–Senior (7+ years)

Final round interview will be in-person

About the Role

Client is seeking a Senior Software Engineer to help design, build, and scale core systems that power internal and customer-facing platforms. This role requires strong API engineering, backend expertise, and the ability to partner with both internal teams and external technology partners.

Key Responsibilities

Design, build, and maintain scalable, high-performance backend services and APIs using C#

Develop RESTful APIs documented using OpenAPI (Swagger) standards

Utilize AI-powered tools to support efficient, high-quality software development

Optimize application performance, reliability, and scalability

Build and maintain integrations with internal systems and external partners

Contribute to architecture, modernization, and code quality initiatives

Troubleshoot and resolve complex production issues

Collaborate closely with business stakeholders and external partners

Mentor and support other engineers

Technology Environment

C#, .NET / ASP.NET

RESTful APIs, OpenAPI / Swagger

IIS, containerized services

PostgreSQL and relational databases

GitHub

AI-assisted development tools

React (nice to have)

Windows Servers, VM and container deployments

Qualifications

7+ years of professional software development experience

Strong backend development experience in C#

Proven ability to build scalable, performant systems

Experience with APIs using OpenAPI standards