Junior Software Engineer

Looking for an opportunity to make an impact?

At Leidos, we deliver innovative solutions through the efforts of our diverse and talented people who are dedicated to our customers’ success. We empower our teams, contribute to our communities, and operate sustainably. Everything we do is built on a commitment to doing the right thing for our customers, our people, and our community. Our Mission, Vision, and Values guide the way we do business.

Your greatest work is ahead!

Leidos Defense Systems is seeking a talented Software Engineer to develop high-performance applications supporting Hardware-in-the-loop laboratories for payloads and sensors. This role is ideal for engineers who enjoy building performant software today while growing into broader system-level and real-time development over time. We have offices across the United States engaging in the defense, space, cyber and commercial fields, we provide responsive, cost-effective engineering, scientific and IT solutions.

If this sounds like the kind of environment where you can thrive, keep reading!

Leidos Defense Systems Sector provides a diverse portfolio of systems, solutions, and services covering land, sea, air, space, and cyberspace for customers worldwide. Solutions for Defense include enterprise and mission IT, large-scale intelligence systems, command and control, geospatial and data analytics, cybersecurity, logistics, training, and intelligence analysis and operations support. Our team is solving the world’s toughest security challenges for customers with “can’t fail” missions. To explore and learn more, click here!

Are you ready to make an impact? Share your resume with us today!

Primary Responsibilities:

Candidate will support space and munition programs develop user-facing and simulation software that interfaces with high-performance sensor and data processing systems. These applications are tightly coupled with real-time data pipelines and hardware systems, requiring strong understanding of performance, data flow, and system behavior.

Engineers in this role are expected to grow into broader system ownership over time, contributing across application, middleware, and real-time components as needed.

• Design, develop, and maintain C++-based applications and backend systems

• Build software supporting data processing, visualization, and system control

• Analyze and improve performance, latency, and scalability of software systems

• Collaborate with cross-functional teams including software, systems, and hardware engineers

• Support integration, testing, and deployment of software in test environments

• Contribute to systems and features end-to-end, from development through deployment and improvement

Basic Qualifications:

Candidate must have 2-4 years of experience in software development and possess a bachelor’s degree or higher in Electrical Engineering, Computer Engineering, or Computer Science degree from an ABET-accredited school.

Candidate must have excellent teamwork skills and possess strong fundamentals in the following:

• Proficiency in modern C++

• Experience with Linux-based systems

• Experience with higher-level user application development

• Experience working in performance-sensitive, distributed, or systems-oriented applications

• Experience with multithreaded or concurrent programming

• Problem-solving skills and ability to work effectively in a team environment

• Must have the ability to obtain and maintain a secret clearance.

Preferred Qualifications:

Candidate with additional skills in the following is preferred:

• Experience with messaging frameworks (e.g., ZeroMQ or similar)

• Experience with communication protocols

• Experience with containerization and CI/CD pipelines

• Experience with Python

• Familiarity with AI coding assistants (e.g., Claude Code)

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:

August 17, 2026

Pay Range:

Pay Range $69,550.00 - $125,725.00

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.