Senior Full Stack .NET Developer / Principal Backend Engineer

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Overview <\/span><\/b>
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This role serves as a senior technical leader responsible for driving backend architecture, guiding engineering best practices, and contributing across the full technology stack. The position focuses heavily on backend systems built with C# and .NET, while also supporting front\-end integration efforts when needed. The engineer in this role will help shape the architectural vision, elevate engineering quality, and provide technical mentorship to the broader team. <\/span>
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Key Responsibilities <\/span><\/b>
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Backend & Full\-Stack Development <\/span><\/b>
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• Design, develop, and maintain backend applications using C#, .NET Framework, .NET Core, and .NET 8<\/b> . <\/span>
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• Build and optimize REST APIs <\/b> , including API versioning and BFF (Backend\-for\-Frontend) patterns. <\/span>
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• Lead data modeling and work extensively with SQL Server <\/b> , including stored procedures, performance tuning, and Dapper (repository\/unit\-of\-work patterns). <\/span>
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• Modernize or translate existing WPF <\/b> components where needed. <\/span>
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• Implement secure authentication flows such as OAuth2<\/b> and OpenIddict <\/b> , including support for server\-to\-server interactions. <\/span>
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• Collaborate closely with front\-end engineers to ensure seamless React\/TypeScript <\/b> integration. <\/span>
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  Architecture & Technical Leadership <\/span><\/b>
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  • Drive the architectural direction across products, ensuring scalability, reliability, and maintainability. <\/span>
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  • Set and uphold high standards for engineering hygiene, code quality, and design practices. <\/span>
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  • Mentor senior and junior engineers, providing guidance in system design, coding practices, and problem\-solving. <\/span>
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  • Translate complex technical topics into clear communication for both technical and non\-technical stakeholders. <\/span>
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  • Identify, advocate for, and drive “delighter” features and improvements that enhance customer value. <\/span>
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    Cloud, DevOps & Infrastructure <\/span><\/b>
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    • Lead the design and operation of large\-scale cloud services using AWS (EC2 and related services)<\/b> or other major public cloud platforms. <\/span>
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    • Apply DevOps and security best practices across development and deployment workflows. <\/span>
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    • Utilize containerization and orchestration technologies such as Docker <\/b> and Kubernetes <\/b> . <\/span>
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    • Contribute to evolving infrastructure that supports data workflows and emerging AI\-related systems. <\/span>
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      Cross\-Functional Collaboration <\/span><\/b>
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      • Partner with product, data, and engineering teams to shape technical strategies and deliver high\-impact initiatives. <\/span>
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      • Understand user needs and customer workflows to inform system improvements and product direction. <\/span>
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      • Operate effectively in a fast\-paced environment with high ambiguity, balancing technical and business priorities. <\/span>
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        Requirements <\/h3>

        
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        Required Qualifications <\/span><\/b>
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        • Bachelor’s degree in Computer Science or a related field. <\/span>
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        • 12+ years of experience building and operating large\-scale cloud services or distributed systems. <\/span>
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        • Expert\-level proficiency in C#<\/b> and the .NET ecosystem <\/b> (.NET Framework, .NET Core, .NET 8). <\/span>
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        • Strong experience with: <\/span>
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          • SQL Server <\/span><\/b> , relational databases, and performance optimization <\/span>
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          • REST API <\/span><\/b> design <\/span>
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          • Dapper ORM <\/span><\/b>
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          • OAuth2, OpenIddict, and modern authentication patterns <\/span><\/b>
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          • Demonstrated experience with at least one major cloud provider (AWS, Azure, or GCP). <\/span>
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          • Proficiency in at least one additional programming language (Java, TypeScript\/JavaScript, Golang, Python, etc.). <\/span>
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          • Experience with Docker <\/b> , Kubernetes <\/b> , or other container orchestration systems. <\/span>
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          • Ability to work directly with end users or customers to understand requirements and user journeys. <\/span>
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          • Strong communication skills with the ability to clearly articulate technical decisions and trade\-offs. <\/span>
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          • Proven track record of developing technical strategies and executing them successfully. <\/span>
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          • Ability to raise the engineering bar for quality, reliability, security, and maintainability. <\/span>
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          • Demonstrated success collaborating across teams and driving complex cross\-functional initiatives. <\/span>
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            Nice\-to\-Have Qualifications <\/span><\/b>
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            • Strong front\-end experience with React <\/b> and modern TypeScript frameworks. <\/span>
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            • Experience supporting or architecting infrastructure for AI pipelines <\/b> . <\/span>
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            • Familiarity with NoSQL technologies, message queues, or event\-driven architectures. <\/span>
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            • Experience with WPF modernization or transition to web\-based UI frameworks. <\/span>
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              Benefits <\/h3>
              
              

              
              

              Benefits <\/span><\/b>
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              • Competitive salary ($180\-200+k) and performance\-based bonus opportunities <\/span>
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              • Comprehensive health, dental, and vision coverage <\/span>
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              • Retirement plan options <\/span>
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              • Generous paid time off and holiday schedule <\/span>
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              • Professional development and continuing education support <\/span>
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              • Flexible work arrangements where applicable <\/span>
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