Senior .NET Developer in New York at Jobgether

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Senior .NET Developer based in United States.

This is a senior, hands-on engineering opportunity focused on building and operating a high-availability enterprise application in a secure AWS GovCloud environment.
You will take technical ownership of a complex production codebase and contribute across architecture, development, deployment, troubleshooting, and continuous improvement.
The platform uses a cloud-native microservices architecture processing millions of messages each month.
You will work with modern .NET, PostgreSQL, RabbitMQ, AWS SQS, Docker, Kubernetes, Rancher, and AWS cloud services.
The role also embraces AI-assisted software development, requiring strong engineering judgment to validate AI-generated code for security, quality, performance, and maintainability.
You will collaborate closely with technical leads, operations, and engineering teams while mentoring developers and helping establish strong engineering practices.
This position is well suited to an experienced developer who thrives on complex distributed systems, production ownership, and mission-critical Federal technology.

• Serve as a senior hands-on developer responsible for the design, development, maintenance, modernization, and continuous improvement of a large-scale production application.
• Take ownership of a substantial application codebase and collaborate with technical leadership to establish technical direction, engineering standards, and development best practices.
• Design, develop, enhance, and maintain microservices and RESTful APIs using C# and modern .NET technologies.
• Build and support cloud-native applications deployed in AWS, including secure Federal environments such as AWS GovCloud.
• Design and maintain scalable, resilient, and highly available services capable of processing millions of messages each month.
• Develop asynchronous and event-driven solutions using RabbitMQ, AWS SQS, and related messaging technologies.
• Design, develop, and optimize data access and persistence solutions using PostgreSQL and AWS RDS.
• Develop, deploy, troubleshoot, and maintain containerized applications using Docker and Kubernetes, including environments managed through Rancher.
• Support the integration and operation of machine learning capabilities within the application's microservices architecture.
• Use AI-assisted development tools, code-generation technologies, AI agents, and development frameworks to accelerate engineering productivity while maintaining rigorous technical standards.
• Review AI-generated code and validate its architecture, security, maintainability, performance, testing, and compliance with established coding standards.
• Conduct code reviews, mentor developers, troubleshoot complex technical issues, and contribute to engineering best practices.
• Maintain code quality and security through automated scanning and static analysis tools such as SonarQube.
• Manage source code and participate in CI/CD and DevSecOps workflows using Azure DevOps.
• Diagnose and resolve complex performance, scalability, reliability, messaging, database, integration, and infrastructure issues across the technology stack.
• Partner with operations and engineering teams to monitor production health, maintain application availability, and resolve incidents.
• Support production releases, deployments, troubleshooting, and incident response, including occasional after-hours support for planned releases and critical incidents.
• Identify and implement improvements in architecture, performance, resiliency, observability, automation, and developer productivity.
• Participate in Agile planning, estimation, technical design reviews, and continuous improvement initiatives.

• Bachelor's degree or equivalent experience in Computer Science, Engineering, Information Technology, or a related technical discipline.
• 8+ years of professional software development experience, including significant experience supporting enterprise-scale production applications.
• Expert-level hands-on experience with C#, .NET Core, and modern .NET, including .NET 8, 9, 10, or comparable versions.
• Strong experience designing and developing RESTful APIs and microservices-based architectures.
• Proven experience developing and operating applications in AWS; AWS GovCloud experience is preferred.
• Strong production experience with Docker and Kubernetes, including Kubernetes management platforms such as Rancher.
• Experience developing asynchronous, event-driven, and message-based applications using RabbitMQ, AWS SQS, or comparable technologies.
• Strong relational database development experience with PostgreSQL, including database design, query optimization, and performance troubleshooting.
• Experience with AWS RDS or comparable managed relational database services.
• Strong understanding of distributed systems, high-availability architectures, scalability, resiliency, and production performance.
• Experience troubleshooting high-volume production systems across application, database, messaging, container, and infrastructure layers.
• Demonstrated ability to take technical ownership of a complex codebase and independently drive sophisticated engineering initiatives.
• Experience conducting code reviews and providing technical guidance, coaching, and mentorship to other developers.
• Hands-on experience with AI-assisted development and code-generation tools such as GitHub Copilot, ChatGPT, or comparable technologies.
• Ability to apply sound engineering judgment when using AI tools, including validating, securing, testing, and maintaining AI-generated code.
• Experience with SonarQube or similar static code analysis and quality platforms.
• Experience with Azure DevOps repositories, source control, CI/CD pipelines, and modern DevSecOps practices.
• Strong understanding of secure software development practices within enterprise and Federal environments.
• Ability and willingness to provide occasional after-hours support for production releases and critical incidents.
• U.S. citizenship required.
• Experience with AWS GovCloud, mission-critical Federal applications, machine learning integrations, AI agents, Infrastructure as Code, observability, and Federal frameworks such as FISMA, NIST, or FedRAMP is preferred.
• Experience working in Agile/Scrum and DevSecOps environments and relevant AWS, Kubernetes, or cloud certifications are advantageous.

• Annual salary range of $130,000–$185,000, with actual compensation determined by factors including skills, experience, training, location, and benefits eligibility.
• Comprehensive medical, dental, and vision insurance beginning the first day of the month following employment.
• 401(k) plan with immediately vested employer contributions and no employee matching requirement.
• Generous paid time off, plus one additional paid wellness day each calendar year.
• Ten paid federal holidays.
• Pet insurance.
• Tuition reimbursement and internal training programs.
• Company-sponsored industry certifications and professional development opportunities.
• Collaborative and dynamic work environment with team-building activities and wellness events.
• Community volunteering opportunities and company-sponsored social and family events.
• Quarterly headquarters days and opportunities to connect with colleagues.
• Remote work flexibility.
• Opportunity to work on innovative digital transformation initiatives supporting Federal Government missions.