Senior Backend / API Developer (Job ID:4208)

Valkyrie • Huntsville, AL

20d • Onsite

About The Position

Valkyrie Enterprises has an immediate need for a Senior Sr Backend / API Developer (.NET Focus) on-site in Huntsville, AL.
Join the team responsible for the Missile Defense System (MDS) Ground Test (GT) scenario design for the Missile Defense Agency (MDA).
MDA GTs are used to assess our nation’s defense systems through a variety of HWIL and simulation tests.
Excellent opportunity to work on cutting-edge defense technologies while contributing to the security of our nation.
Primary backend engineer responsible for designing, building, and maintaining APIs and service layers that power a suite of web applications.
The position emphasizes reliability, maintainability, and scalability of backend systems, with a strong focus on structured data, service architecture, and integration with downstream systems (including AI-enabled features via external services).
Hands-on engineering role embedded within a development team, working closely with frontend developers, database specialists, and DevOps personnel to deliver production-grade software in a controlled, enterprise environment.

Requirements

• Must have a BS in Engineering, Math, Physics, or similar technical discipline and at least 5–10+ years of professional software development experience.
• Must have strong proficiency in C# and the .NET ecosystem (including .NET Framework 4.8 and/or .NET 5+).
• Must have proven experience designing and building RESTful APIs and backend services.
• Must have experience working in production environments with real-world users, data, and operational constraints.
• Must have a solid understanding of software architecture principles (layered architecture, service boundaries, separation of concerns).
• Must have experience debugging and maintaining complex systems over time.
• Must have the ability to work independently and take ownership of backend systems.
• Must have the ability to obtain and maintain a Secret clearance.

Nice To Haves

• Experience integrating with AI/ML services (REST APIs, data pipelines, inference workflows), preferred.
• Familiarity with Azure DevOps (build/release pipelines, repos, work items), preferred.
• Experience working in controlled or restricted environments (e.g., air-gapped systems, secure networks), preferred.
• Familiarity with frontend technologies (JavaScript, MVC frameworks, or similar) for effective collaboration, preferred.
• Understanding of authentication/authorization patterns (e.g., role-based access, enterprise auth systems) , preferred.
• Agile / Scrum team experience, preferred.
• Active SECRET security clearance, preferred.

Responsibilities

• Design, develop, and maintain RESTful APIs and backend services using C# and the .NET ecosystem
• Build and support service-oriented architectures that enable modular, maintainable application design
• Integrate backend systems with external or internal AI/ML services (API consumption, data exchange, orchestration)
• Collaborate with frontend developers to define API contracts and ensure seamless UI integration
• Support application lifecycle activities including debugging, performance tuning, and production issue resolution
• Contribute to architectural decisions, including service boundaries, data flow, and system design patterns
• Ensure code quality through testing, code reviews, and adherence to development standards
• Participate in deployment and release processes
• Document system design, APIs, and key technical decisions for long-term maintainability

Benefits

• Valkyrie Enterprises provides a variety of benefits to eligible employees to support your best health, wellness, and future, to include medical/dental/vision options, company paid life and disability insurances, 401k with match, education reimbursement, as well as company paid holidays and paid time off (PTO).

What This Job Offers

• Job Type: Full-time
• Career Level: Mid Level
• Number of Employees: 11-50 employees