Senior .NET Developer

Job Description NetImpact Strategies is seeking a Senior .NET Developer to join our talented team supporting the development, modernization, and operation of a high-availability, enterprise-scale application in an AWS GovCloud environment. The ideal candidate is a highly experienced, hands-on developer who can take ownership of a complex production codebase, provide technical leadership, and work closely with technical leads, operations teams, and other stakeholders to deliver secure, scalable, resilient, and maintainable solutions. The application is built on a cloud-native microservices architecture consisting of approximately a dozen services and processes millions of messages each month. The technology stack includes .NET 10 / .NET Core, REST APIs, PostgreSQL on AWS RDS, RabbitMQ, AWS SQS, Docker, Kubernetes managed through Rancher, and AWS GovCloud. The environment also makes extensive use of AI-assisted software development tools and AI development frameworks to accelerate engineering while maintaining rigorous standards for code quality, security, and maintainability. This is a hands-on senior development role requiring strong coding skills, technical ownership, production troubleshooting capabilities, and the ability to work across all layers of a mission-critical enterprise application. Key Responsibilities Serve as a senior, hands-on developer responsible for the design, development, maintenance, and continuous improvement of a large-scale production application Take ownership of the application codebase and work closely with the Technical Lead to establish technical direction, engineering standards, and development best practices Design, develop, enhance, and maintain microservices and RESTful APIs using C# and .NET 10 / .NET Core Develop and support cloud-native applications deployed within AWS GovCloud Design and maintain scalable, resilient, and highly available services capable of processing millions of messages per month Develop and support event-driven and asynchronous processing solutions leveraging RabbitMQ and AWS SQS Design, develop, and optimize data access and persistence solutions using PostgreSQL hosted in AWS RDS Develop, deploy, troubleshoot, and maintain containerized applications using Docker and Kubernetes, including Kubernetes environments managed through Rancher Support the integration and operation of machine learning capabilities within the application’s microservices architecture Utilize AI-assisted development tools, code-generation technologies, AI agents, and AI development frameworks to improve developer productivity and accelerate software delivery Review AI-generated code and ensure it meets application architecture, security, maintainability, performance, and coding standards Perform code reviews, mentor developers, troubleshoot complex technical issues, and help establish engineering best practices across the development team Maintain high standards for code quality and security through automated scanning and static code analysis, including SonarQube Manage source code and participate in development and CI/CD workflows using Azure DevOps (ADO) Diagnose and resolve application performance, scalability, reliability, messaging, database, and integration issues across the technology stack Partner closely with operations and engineering teams to monitor and maintain production application health and availability Support production releases, deployments, troubleshooting, and incident resolution Participate in occasional after-hours support for planned production releases and critical production incidents, in coordination with the operations team Identify opportunities to improve application architecture, performance, resiliency, observability, automation, and developer productivity Participate in Agile development activities, technical planning, estimation, design reviews, and continuous improvement initiatives Qualifications Required 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 developing and supporting enterprise-scale production applications Expert-level hands-on development experience with C#, .NET Core, and modern .NET (.NET 8/9/10 or similar) Strong experience designing and developing RESTful APIs and microservices-based architectures Experience developing and operating applications in AWS, preferably AWS GovCloud Strong experience with Docker and Kubernetes in production environments Experience with Kubernetes management platforms such as Rancher Experience developing asynchronous, event-driven, or message-based applications using technologies such as RabbitMQ and AWS SQS 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 application performance Experience supporting high-volume production systems and diagnosing complex issues across application, database, messaging, container, and infrastructure layers Demonstrated ability to take technical ownership of a substantial codebase and independently drive complex engineering efforts Experience performing code reviews and providing technical guidance and mentorship to other developers Experience with AI-assisted development and code-generation tools such as GitHub Copilot, ChatGPT, or comparable AI development technologies Ability to effectively use AI tools while applying strong engineering judgment to validate, secure, test, and maintain AI-generated code Experience with SonarQube or similar static code analysis and code-quality platforms Experience w