Backend Software Engineer — Secure Mission Systems

Backend Software Engineer — Secure Mission Systems Location: Mainly remote, with onsite sprint planning in Laurel, Maryland, approximately every six weeks Clearance: U.S. citizenship and an active final DoD Secret clearance required Anticipated Start: November 2026 This opportunity is contingent upon contract award and final customer approval. Build Secure Software for a High-Impact Defense Mission Join Rackner to build secure backend services that support mission-planning and decision-support capabilities for a Department of Defense customer. You will take hands-on ownership of APIs, service integrations, data flows, and automated testing—not simply complete isolated development tickets. The role offers exposure to distributed systems, geospatial data, secure container platforms, and backend services supporting AI-enabled capabilities. What You Will Do Design, build, test, and integrate secure backend services and APIs using Python and/or C#. Develop REST services with FastAPI and support service-to-service communication through technologies such as gRPC. Build reliable asynchronous workflows using Celery, RabbitMQ, or comparable messaging tools. Develop and integrate relational and geospatial data solutions using PostgreSQL and PostGIS. Containerize and deploy services through OpenShift or Kubernetes. Write unit and integration tests that strengthen software quality and delivery confidence. Work within GitLab-based development and CI/CD workflows. Investigate defects, security findings, failed integrations, and service issues. Participate in code reviews, technical reviews, and vulnerability-remediation efforts. Produce clear software designs, workflow descriptions, and technical documentation. Collaborate with frontend, AI/ML, cybersecurity, DevSecOps, and customer engineering teams. What You Bring At least four years of professional software-development experience. A bachelor’s degree in computer science or a related field. Hands-on experience building backend services, APIs, or distributed applications. Experience with Python, C#, or a comparable backend language. Understanding of API design, data flows, error handling, automated testing, and source control. Familiarity with secure software-development lifecycle practices. Ability to clearly explain the systems you personally built, the decisions you made, and how your work was tested and delivered. Experience That Will Help You Stand Out FastAPI or another Python web framework. RabbitMQ, Celery, gRPC, or similar messaging and service-integration tools. PostgreSQL, PostGIS, geospatial data, or mapping applications. OpenShift, Kubernetes, GitLab CI/CD, or secure container delivery. Defense, mission-planning, decision-support, or other regulated software environments. Integration of backend services with LLM, retrieval-augmented generation, or other AI-enabled components. You do not need to be the deepest expert in every technology listed. Strong backend fundamentals, credible hands-on experience, and the ability to learn within a secure delivery environment matter most. Why Rackner At Rackner, you will build technology that supports critical defense and public-sector missions. This role offers broader ownership across backend engineering, secure delivery, distributed services, automated testing, and collaboration with software, AI/ML, cloud, and cybersecurity teams. Rackner has delivered more than $30 million in recent federal awards. We are looking for an engineer who can help turn complex mission needs into secure, dependable software. Benefits & Professional Growth Competitive compensation Company-supported certifications 401(k) with 100% company match up to 6% Medical, dental, vision, life, and disability coverage Paid time off and company holidays Remote-work support and home-office equipment plan Fitness and wellness reimbursement Weekly pay schedule Professional-development and growth opportunities Apply If you want to build secure backend services that directly support an important defense mission, we would like to hear from you.