Principal Software Engineer

Are you ready to join Leidos all-star team? Through training, teamwork, and exposure to challenging technical work, let Leidos show how to accelerate your career path.

Leidos has an exciting opening for you as our next TS/SCI cleared Principal Software Engineer supporting a long-term DIA-NDOC DOMEX Technology Platform (DTP) contract. You will work closely with Systems Engineers, Software Engineers, Architects, and Operations Engineering/Manager on a broad scope of activities extending across the development of systems to include middle-tier and backend engineering tasks.  Have impact as part of a mission focused, solutions oriented, and adaptive team that values innovation, collaboration, and professional development. While most work is conducted on-site at our client location in Bethesda, MD, we offer a flexible schedule and, occasionally, some tasks may be performed remotely. The percentage of remote work will vary based on client requirements/deliverables.

Specifically, we are looking for a skilled Python developer to join our team to build and maintain scalable microservices that interface with Kafka for real-time messaging and Elasticsearch for data indexing and search. You'll deploy and monitor your services in a Kubernetes environment and collaborate with cross-functional teams in designing reliable, observable, and secure systems. Our client’s overall mission is to design and implement a data centric architecture that leverages cloud-based computing, artificial intelligence (Al), machine learning (ML) and cross-domain transfer systems.

You will work closely with the team on the following key tasks

• Design, develop, test, and maintain Python microservices
• Implement message consumers and producers with Apache Kafka
• Integrate with Elasticsearch for real-time and batch data indexing and querying
• Write unit and integration tests; ensure high code coverage and reliability
• Build CI/CD pipelines for your services and deploy them in Kubernetes clusters
• Participate in design discussions, code reviews, and architecture planning
• Monitor and troubleshoot production issues with observability tools
• Contribute to technical documentation and knowledge sharing within the team
• Utilizes software engineering and design methodologies appropriate to the development, integration, and production environment
• Foster an environment of collaboration with the different team members in the goal of providing quality service and product to our customers

To be successful in this role you need these skills (required):

• Bachelor’s Degree and 12 or more years of prior relevant experience or Masters with 10 or more years of prior relevant experience. Experience can be considered in lieu of a degree.
• Must possess an Active Top Secret/SCI clearance and ability to obtain and maintain a Polygraph
• Proficiency in Python and related backend frameworks (e.g., FastAPI, Flask).
• Experience with containerization, especially with Docker
• Experience in Extraction, Transformation, and Load (ETL)
• Hands-on development experience in a Linux environment including bash or bash-like scripting
• Strong understanding of RESTful APIs and microservice architecture
• Hands-on experience with Kubernetes: deploying, monitoring, and debugging services
• Understanding of common design patterns, security practices, and logging/monitoring principles
• Familiarity with Git and collaborative workflows (PRs, reviews)
• Experience with DevOps practices and tools including Continuous Integration/Continuous Delivery (CI/CD) tools and practices, especially Gitlab or Jenkins
• Strong verbal and written communication skills
• Experience with AGILE practices
• Enthusiastic with the ability to work well in a team and a self-starter who can work on their own

You will wow us even more if you have some of these skills:

• Experience with designing and implementing software development kits
• Familiarity DGX (Deep GPU Xceleration)
• Active Security+ certification and ability to obtain Privileged User Account (PUA) certification by the Government
• Elasticsearch certifications or other program stack related certifications
• Experience of a production/enterprise systems at scale
• Knowledge of distributed systems concepts (e.g., idempotency, eventual consistency)
• Familiarity with schema registries and Kafka streaming patterns
• Experience blending analytical methodologies and leveraging existing COTS/GOTS/OS tools in an unconventional manner.
• Experience with Amazon Web Services (AWS/C2S)
• Familiarity or experience with building applications around Large Language Models, Agentic AI

#NMECDTP-Leidos

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Original Posting:

September 22, 2026

Pay Range:

Pay Range $131,300.00 - $237,350.00

The Leidos pay range for this job level is a general guideline only and not a guarantee of compensation or salary. Additional factors considered in extending an offer include (but are not limited to) responsibilities of the job, education, experience, knowledge, skills, and abilities, as well as internal equity, alignment with market data, applicable bargaining agreement (if any), or other law.