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Salary
$90k – $130k per year
Location
In office (Lexington Park, 8am - 5pm)
Seniority
Junior
Employment
Full-Time

Confirmed on the employer's own hiring board on Oct 27, 2026. First seen by Alion on Oct 25, 2026.

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Specialty EngineeringBuilt for Mission.. S3I Engineering delivers systems integration, cybersecurity, and operational support across the Software, Systems, Cyber, and Hardware Engineering disciplines — with deep expertise in DOD platforms.

S3I Engineering provides specialty engineering services, systems integration, and operational support to US Government agencies. Our technical expertise covers multiple facets of the Software, Systems, Cyber, and Hardware Engineering disciplines. Our engineers have expert knowledge of the critical mission management systems and their deployment on various DOD, DHS, and other platforms.

S3I is currently looking for entry and mid-level Systems Engineers. You will be working with cutting-edge technology to test complex mission management systems and their sensors. From testing capabilities to optimizing performance and reliability, your expertise will play a pivotal role in ensuring mission success. If you love to solve hard complex problems and are willing to embrace the challenge, embark on a career where every day brings new opportunities to push the boundaries of what is possible. Join us and be a part of shaping the future.

Job Title: Systems Engineer I

Work Schedule: M-F, 8AM-5PM, Flexible

Job Classification: Exempt

Primary Location: Lexington Park, MD

Travel: 12-18 weeks per year

Salary Range: $90,000 to $130,000 depending on experience and skill set

Position Description: Systems Engineer I

Position Summary

The Systems Engineer I supports the development, integration, testing, and analysis of mission systems and sensors deployed across DoD platforms. This role focuses on troubleshooting, system configuration, testing execution, and technical documentation within structured engineering processes. This work includes laboratory and field test activities associated with complex sensor and mission systems.

Key Responsibilities

  • Assist in the installation, configuration, and testing of mission systems with related sensors and other integrated software within government labs and aircraft environments.
  • Conduct basic troubleshooting using Linux command-line tools and established diagnostic procedures.
  • Configure test bench systems to support validation of software requirements and system behavior.
  • Support reproduction of system anomalies reported from fielded systems and assist in documenting root cause indicators.
  • Participate in design reviews under supervision, offering technical observations aligned with requirements derivation.
  • Prepare field test reports, summary documents, and structured notes for senior engineers and government personnel.
  • Follow DoD and DCSA cybersecurity practices during configuration, testing, and system interaction.
  • Provide dependable and professional support to government stakeholders and partner organizations.
  • Support tasking outside of normal business hours (<10>
  • Travel to support tasking approximately 12-18 weeks annually

Required Qualifications

  • Bachelor of Science in Engineering, Computer Science, Computer Hardware, Mathematics, Physics, or related technical field; or equivalent experience.
  • Foundational experience in Linux-based troubleshooting and system analysis across separate interdependent projects.
  • Familiarity with constructing or configuring basic computer systems in a Linux environment with multiple interdependent services or projects.
  • Ability to obtain DoD 8570/8140 compliance by certification or education within 6 months of starting.
  • Strong organizational and communication skills.
  • The ability to work within dynamic test environments across organizations.
  • US Citizenship and eligibility for a TS/SCI clearance.
  • Ability to access government facilities and travel between office and government sites as required.

Desired Qualifications

  • Familiarity with mission systems or sensor technologies such as EO/IR, Radar, SIGINT.
  • Exposure to DoD cloud environments including IL5 or higher.
  • Basic experience with software configuration management tools such as Git.
  • Previous experience with Minotaur systems is strongly desired.

Physical Requirements

  • Ability to lift and carry approximately 40 lbs.
  • Ability to perform work in confined spaces during system testing.
  • Ability to access government locations, facilities, and vessels.

S3I Engineering, LLC is a small business supporting the US Navy. S3I offers a generous benefits package including Medical and Dental benefits, Holiday and Paid Leave, 401K with Matching, and a Profit-Sharing Plan. S3I Employee compensation is highly competitive and commensurate with experience. If you have any of these skills, we encourage you to apply!

EEO

Women, minorities, individuals with disabilities, and Veterans are encouraged to apply. S3I Engineering is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, pregnancy, sexual orientation, gender identity, national origin, age, protected Veteran status, or disability status.

S3I will provide a reasonable accommodation to individuals with disabilities and disabled Veterans who need assistance to apply.

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