Key skills
PythonC#API designFastAPIgRPCCeleryRabbitMQPostgreSQLPostGISOpenShiftKubernetesGitLab CI/CDSecure software-development lifecycle practicesAutomated testingSource controlCAIMLLLMGitLab CIGitLabSource ControlCI/CDCommunication
About this role
Rackner is a company focused on building secure technology for critical defense and public-sector missions. The Backend Software Engineer will take ownership of developing secure backend services and APIs to support mission-planning and decision-support capabilities for a Department of Defense customer.
Responsibilities:
- 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
Requirements:
- 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
- U.S. citizenship and an active final DoD Secret clearance required
- 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