Leidos’ Security Enterprise Solutions (SES) operation is seeking a Senior Software Engineer (C ) in Tewksbury, MA to join our cross-functional engineering team using cutting edge technology to develop truly novel solutions that make travel and trade safer, healthier, and more efficient on a global level.

As a Senior Software Engineer (C ) on our diverse and collaborative team, you will work alongside our expert Scientists and Engineers, contributing to cutting edge technology with global impact on security detection. This isn’t your run-of-the-mill software development – you’ll be honing your engineering skills with embedded products, real-time programming, and object oriented design, all with the support of a management team focused on your professional growth and advancement.

The Senior Software Engineer uses knowledge and experience with Object-Oriented C development to perform job functions. Individual will be responsible for developing applications for our distributed turn-key systems. Working under general supervision in a small team environment, your primary responsibility will be to modify, develop, and troubleshoot multi-tiered distributed applications and systems. The duties and responsibilities may change from time to time without notice and include but are not limited to the duties described below.

Primary responsibilities include:

Design, build, and maintain efficient, reusable, and reliable C code using good OOP/OOAD techniques for our systems.
Optimize, identify bottlenecks, bugs, and devise solutions to problems including: Maintain code quality, revision control and organization, Analyze customer issues and identify and implement solutions, Participate and contribute within a defined software development process.
Occasional travel to customer sites may be required. Travel may be domestic and international.

Basic Qualifications:

Requires BS degree and 8 years of prior relevant experience or master’s with 6 years of prior relevant experience. Additional years of experience will be considered in lieu of education.
Must have the ability to obtain a Public Trust clearance (US citizenship required).
Strong Understanding C and OOP/OOAD
Strong understanding of data structures, algorithms, and software design solutions.
Strong understanding of memory management, multicore processors, and distributed systems design.

Preferred Skills:

Linux Platform development
Interfacing with hardware and real-time debugging.
Good working knowledge of SQL
Working knowledge of Cybersecurity
Working knowledge of networking solutions.
Graphics Design, GUI development, DirectX, etc. (Highly Desirable)
Excellent verbal, written and interpersonal communication skills
Advanced degree, preferred

Check out the links below to learn more about Security Enterprise Solutions (SES)
https://careers.leidos.com/pages/security-enterprise-solutions
https://www.leidos.com/markets/aviation/security-detection

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:

December 8, 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 $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.

Job ID

Senior-Software-Engineer-C--_R-00171739

Security Clearance

Public Trust

About Leidos

Company Profile