Leidos’ Defense Sector is seeking a Senior Software Engineer (RTSS) to support an Army Program focused on delivering advanced capabilities for operational decision-making in complex and dynamic environments. The Senior Software Engineer (RTSS) leads the design, development, and integration of real-time and safety-critical software systems. This role requires deep technical expertise in deterministic software behavior, embedded platforms, and low-level system interactions. The engineer will drive architectural decisions, mentor junior developers, and ensure that all software meets stringent performance, reliability, and compliance requirements. This position is ideal for someone who thrives in complex, time-sensitive environments and can influence technical direction across multidisciplinary teams.

Locations include Aberdeen Proving Ground, MD; Fort Belvoir, FL; Tampa, FL

This position is contingent upon program award, anticipated late March.

Primary Responsibilities:

• Lead the design and development of real‑time and embedded software components for mission‑critical systems.
• Architect, implement, and optimize software to meet deterministic timing, performance, and reliability requirements.
• Conduct advanced debugging, profiling, and root‑cause analysis on embedded targets and real‑time operating systems (RTOS).
• Collaborate with systems, hardware, and test engineering teams to ensure seamless integration across the full system lifecycle.
• Develop and maintain detailed technical documentation, including design specifications, interface definitions, and verification artifacts.
• Participate in and lead technical reviews, providing guidance on best practices and design improvements.
• Ensure compliance with relevant industry standards, safety requirements, and certification processes.
• Mentor junior and mid‑level engineers, providing technical leadership and code review oversight.
• Support system bring‑up, hardware/software integration, and fielded system troubleshooting.
• Drive continuous improvement in development processes, tooling, and system performance.
• Prepare and maintain detailed engineering documentation, including specifications, test reports, and design artifacts.

Basic Qualifications:

• Bachelor’s degree in computer science, Software Engineering, Electrical Engineering, or related technical field with 8+ years of experience or a Master’s degree with 6+ years of experience. Additional experience may be considered in lieu of a degree.
• Active Secret clearance with the ability to obtain a TS/SCI.
• Professional software engineering experience, with significant work in real‑time or embedded systems.
• Strong proficiency in C and C++ for embedded or low‑level development.
• Experience with real‑time operating systems (e.g., Vx Works, QNX, RTEMS, FreeRTOS).
• Deep understanding of real‑time constraints, scheduling, concurrency, and deterministic system behavior.
• Experience with hardware/software interfaces, device drivers, or board‑level bring‑up.
• Proficiency with debugging tools such as JTAG, logic analyzers, oscilloscopes, or embedded trace tools.
• Strong analytical, problem‑solving, and communication skills.
• Ability to lead technical efforts and collaborate across multidisciplinary teams.

Preferred Qualifications:

• Master’s degree in a related engineering discipline.
• Experience with safety‑critical or regulated environments (DO‑178C, ISO 26262, IEC 61508, MIL‑STD).
• Knowledge of networking protocols, communication buses, or distributed real‑time systems.
• Experience with modeling tools (MATLAB/Simulink), static analysis, or formal methods.
• Familiarity with cybersecurity principles for embedded systems.
• Background in aerospace, defense, robotics, automotive, or industrial control systems.
• Experience with continuous integration, automated testing, or DevOps pipelines for embedded software.
• Ability to influence architecture decisions and drive long‑term technical strategy.

If you're looking for comfort, keep scrolling. At Leidos, we outthink, outbuild, and outpace the status quo — because the mission demands it. We're not hiring followers. We're recruiting the ones who disrupt, provoke, and refuse to fail. Step 10 is ancient history. We're already at step 30 — and moving faster than anyone else dares.

Original Posting:

February 26, 2026

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 $107,900.00 - $195,050.00

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.