Software Engineer, Defense Applications - Clearance Required

LMI; Fort Belvoir (VA); On-site; USD 134,000 - 279,000; Full time

Job summary

LMI is seeking a Staff Software Engineer to build user-facing applications supporting a U.S. Army technology modernization program. This engineer will own application capabilities from user need through production delivery using Palantir Foundry and modern web technologies.

This is a hands-on role for an engineer who can work across the stack, make architectural decisions, and build software directly with users and product teams.

Qualifications

• Bachelor’s degree in CS/SE or related field or equivalent practical experience.
• Eight+ years of professional software-engineering experience.
• Proficiency with JavaScript/TypeScript, React, and modern web-app development.
• Experience building backend services, APIs, and data-intensive applications.
• Experience on Palantir Foundry or similar enterprise data platform.
• Active DoD work experience and ability to obtain/hold Secret clearance.

Responsibilities

• Own design and delivery of user-facing defense applications.
• Build responsive interfaces, backend services, APIs, and data integrations.
• Develop applications using Palantir Foundry capabilities and modern web frameworks.
• Collaborate with Army users and product designers to understand workflows.
• Establish architecture, testing, security, CI/CD, production operations practices.
• Diagnose complex issues across the stack.
• Mentor engineers and contribute to platform decisions.

Skills

JavaScript/TypeScript

React

Backend APIs

Data-intensive apps

Education

Bachelor’s degree

Equivalent experience

Tools

Palantir Foundry

Job description

Overview

LMI is seeking a Staff Software Engineer to build user-facing applications supporting a U.S. Army technology modernization program. This engineer will own application capabilities from user need through production delivery using Palantir Foundry and modern web technologies.

This is a hands-on role for an engineer who can work across the stack, make architectural decisions, and build software directly with users and product teams.

LMI is a new breed of digital solutions provider dedicated to accelerating government impact with innovation and speed. Investing in technology and prototypes ahead of need, LMI brings commercial-grade platforms and mission-ready AI to federal agencies at commercial speed.

Leveraging our mission-ready technology and solutions, proven expertise in federal deployment, and strategic relationships, we enhance outcomes for the government, efficiently and effectively. With a focus on agility and collaboration, LMI serves the defense, space, healthcare, and energy sectors—helping agencies navigate complexity and outpace change. Headquartered in Tysons, Virginia, LMI is committed to delivering impactful results that strengthen missions and drive lasting value.

Responsibilities

• Own the design and delivery of user-facing defense applications.
• Build responsive interfaces, backend services, APIs, and data integrations.
• Develop applications using Palantir Foundry capabilities and modern web frameworks.
• Work directly with Army users and product designers to understand workflows and refine capabilities.
• Establish strong practices for architecture, testing, code review, security, CI/CD, and production operations.
• Diagnose complex application and integration issues across the stack.
• Mentor engineers and contribute to technical decisions across the broader platform.

Qualifications

Minimum Qualifications

• Bachelor’s degree in computer science, software engineering, or a related field, or equivalent practical experience.
• Eight or more years of professional software-engineering experience.
• Strong proficiency with JavaScript or TypeScript, React, and modern web-application development.
• Experience developing backend services, APIs, and data-intensive applications.
• Experience building applications on Palantir Foundry or a comparable enterprise data platform.
• Demonstrated ownership of a significant software capability from architecture through production deployment.
• Experience supporting a Department of Defense customer.
• Active Secret clearance.

Preferred Qualifications

• Experience supporting the U.S. Army.
• Hands-on experience with Palantir Foundry, Army Vantage, OSDK, Workshop, or AIP.
• Experience with Python, Java, Go, or Node.js.
• Familiarity with Army acquisition or program-management processes.
• Experience with cloud platforms, DevSecOps, and AI-assisted development tools.

The target salary range for this position is $134,367 - $278,896

The salary range displayed represents the typical salary range for this position and is not a guarantee of compensation. Individual salaries are determined by various factors including, but not limited to location, internal equity, business considerations, client contract requirements, and candidate qualifications, such as education, experience, skills, and security clearances.

Applicants must meet eligibility requirements for a U.S. Government security clearance. Only US Citizens are eligible for a security clearance. For this position, LMI will only consider applicants with security clearances or applicants who are eligible for security clearances, due to the nature of the work.

Job Locations

US-VA-Fort Belvoir