Senior Software Developer

Senior full-stack engineer to lead design, implementation, and sustainment of mission-critical web applications for defense customers. You will own architecture and delivery across .NET backends, Vue.js front ends, and SQL Server data layers, and shepherd solutions through secure SDLC, security compliance, and fielded deployments. This role requires technical leadership, systems thinking, and proven experience delivering reliable software in controlled or constrained environments.

This position can be worked remote, but strong preference will be given to candidates local to Newport News, VA.

Key responsibilities

• Design and implement scalable, secure backend services using C# (.NET Framework / .NET Core / ASP.NET) that satisfy performance, reliability, and accreditation requirements.
• Build and document RESTful Web APIs, leveraging OpenAPI/Swagger standards for discoverability and integration.
• Build front-end architecture and delivery using Vue.js/Nuxt, TypeScript, tailwind, component design, and modern state management patterns.
• Design relational database schemas, stored procedures, and queries with a focus on performance and maintainability.
• Drive API design and integrations, message patterns, and secure data exchanges.
• Own technical documentation, security artifacts, and deployment packages required for accreditation and fielding.
• Mentor and lead cross-functional teams; review code, set standards, and enforce best practices.
• Establish and maintain automated unit tests (e.g., NUnit) and contribute to overall test coverage strategy.
• Participate in incident postmortems and provide rapid response support for production and field issues.
• Coordinate with product, QA, and systems engineering to meet contract milestones, and audit requirements.

Required qualifications

• Bachelor's Degree with 8 years professional software development experience with substantial full-stack delivery. Experience can be considered in lieu of a degree.
• Ability to obtain and maintain a TS/SCI
• Deep expertise in C# and .NET (Framework and Core/ASP.NET) and proven track record building backend systems.
• Strong mastery of Vue.js (or equivalent FE framework) and modern front-end engineering practices, including TypeScript, component patterns, tailwind, and performance optimization.
• Solid understanding of relational databases (SQL, schema design, performance considerations).
• Solid grasp of secure design principles and secure coding practices aligned to DoD requirements.
• Proven ability to design for constrained or disconnected deployments and to package software for controlled networks.
• Excellent communication skills; ability to present technical tradeoffs to leadership and mentor junior/mid engineers.

Preferred qualifications

• Extensive experience with Microsoft SQL Server: indexing strategies, T-SQL optimization, and capacity planning.
• Prior experience in defense, intelligence, or classified environments; familiarity with accreditation lifecycle.
• Familiarity with performance/load testing and tools (e.g., JMeter) and capacity planning for mission systems.
• Background in data pipelines, integration middleware (e.g., NiFi), or message brokers (ActiveMQ/Artemis, Kafka).

We're not looking for perfectly polished resumes or perfect fits. We're looking for people who break limits, ask hard questions, and don't wait to be told what's next. At Leidos, we're not following the roadmap - we're redrawing it.

Original Posting:
November 13, 2025

For U.S. Positions: While subject to change based on business needs, Leidos reasonably anticipates that this job requisition will remain open for at least 3 days with an anticipated close date of no earlier than 3 days after the original posting date as listed above.

Pay Range:
Pay Range $104,650.00 - $189,175.00

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.