Senior .NET (C#) Backend Developer

Summary

Join Togetherhood as a Senior Backend Engineer and build and modernize backend services using C# and the .NET ecosystem. You will collaborate with product and front-end engineers, design scalable backend applications, upgrade existing applications, refactor legacy code, and maintain internal RESTful APIs. This role requires expertise in designing and documenting RESTful APIs, MySQL optimization, Docker, GitHub Actions, CI/CD, and AWS deployment. You will also work with AI development tools and contribute to a collaborative engineering culture. The position offers competitive salary and benefits, a remote-first work culture, and the opportunity to make a tangible impact.

Requirements

• 5+ years of experience building backend applications with C# and the .NET ecosystem
• Demonstrated expertise designing and documenting RESTful APIs for internal use
• Skilled in MySQL optimization (Amazon RDS) and efficient SQL querying
• Familiar with Docker, GitHub Actions, and CI/CD best practices
• Experienced in deploying and running .NET apps on AWS
• Regular user of AI development tools like Claude, Cursor, or GitHub Copilot
• Strong communication and cross-functional collaboration skills
• Work day overlaps with the Eastern Coast Timezone

Responsibilities

• Lead the design and development of scalable backend applications in C#/.NET
• Apply best practices in architecture and object-oriented design
• Upgrade our existing application from .NET 6 to .NET 9
• Refactor legacy code to implement domain models, introduce robust validation, and reduce technical debt
• Architect and maintain internal RESTful APIs used by our React frontend
• Write clear, developer-friendly API documentation using Swagger/OpenAPI
• Profile and tune applications for speed, stability, and scalability across application and database
• Instrument services with Datadog and build dashboards and alerts
• Collaborate closely with front-end engineers, QA, and product managers in a tight feedback loop
• Participate in agile ceremonies and planning sessions
• Contribute to building the engineering culture of a small, early stage engineering team
• Maintain and improve CI/CD pipelines using GitHub Actions and Docker
• Work within our AWS infrastructure (Elastic Beanstalk, RDS, etc.) to support automation and scaling

Preferred Qualifications

• Experience building modern UIs with React + Vite
• Knowledge of Retool for rapid internal tool development
• Familiarity with TDD and automated testing frameworks
• Experience refactoring legacy .NET apps and applying domain-driven design

Benefits

• Competitive salary and benefits (Health, Vision, Dental) and equity based compensation
• Remote-first, flexible work culture supporting NYC based operations team
• A close-knit, collaborative environment where your work truly matters