Principal Software Engineer

Modern Technology Solutions, Inc (MTSI) supports critical national defense and security programs, and prioritizes a workplace built around employee-first values. This role supports the Missile Defense Agency Next Generation Software Office, focusing on accelerating and modernizing resilient and secure software development, integration, and delivery. You will also benefit from flexible scheduling, strong retirement contributions, professional development support, and a company-funded Employee Stock Ownership Plan (ESOP).

Based in Huntsville, AL (onsite), the Principal Software Engineer role helps enable on-demand and cloud-based capabilities for system-of-systems development, integration, and testing. The work emphasizes engineering rigor and the ability to analyze, design, and improve software approaches across cloud environments and hardware-in-the-loop testing.

Responsibilities

• Provide technical and engineering analysis to support development of on-demand and cloud-based software for system-of-systems development, integration, and testing.

Requirements

• US Citizenship and an active Secret clearance.
• Masters degree in a STEM field with 12+ years working on missile defense-related or other complex, large DoD program/project.
• Experience designing, developing, and managing software libraries and cloud-based software architectures and requirements.
• Experience with hardware in the loop and cloud-based testing to support software development and delivery.
• Experience managing and reviewing application programming interfaces and interface control documents for enabling software used in cloud-based and HWIL environments.
• Experience in artificial intelligence development and tooling and agentic operations.
• Ability to work independently, as a team member, or leading teams and tasks while applying engineering rigor to solve engineering/scientific problems.

Skills and Tools

Experience with the following technologies is relevant to this position: Docker, Kubernetes, AWS, Azure, Terraform, Ansible, and Git.

Benefits and Perks

• Vacation: New hires accrue 20 days of PTO and 10 holidays per year.
• Health Plans: Zero deductible health plans, including an optional zero deductible Blue Cross/Blue Shield plan.
• Flex Schedules: Flex schedules.
• Education/Training: Up to $10,000 annual education and training reimbursement.
• Ownership: Funded Stock Ownership Plan and a company-funded Employee Stock Ownership Plan (ESOP) (separate qualified retirement account).
• 401(k): 6% match with immediate vesting (with immediate vesting up to $9k annually).
• Bonus Opportunity: Semi-annual bonus eligibility (July and December).
• Mentorship: Career mentorship programs.

Preferred Qualifications

• Practical experience with software containerization concepts (for example, Docker, Kubernetes, AWS, Azure) and migrating legacy enterprise applications to cloud-native architectures.
• Strong working knowledge of Agile and Lean software development principles, particularly within a secure DoD DevSecOps framework.
• Infrastructure as Code (IaC): knowledge of or direct experience deploying IaC tools (for example, Terraform, Ansible) to establish reproducible, auditable, and secure cloud environments.
• Experience using modern configuration management and version control platforms (for example, Git) to enforce policy-as-code, baseline management, and compliance configurations.
• Top secret clearance or the ability to qualify for one.

EEO Statement: MTSI embraces nine core values including its first core value of Employees come first. The company is committed to Equal Opportunity and making decisions without regard to race, color, religion, sex, national origin, age, military/veteran status, disability, or any other characteristics protected by applicable law. MTSI also provides reasonable accommodations to applicants and employees with physical and/or mental disabilities.

MTSI notes it has grown every year since its founding in 1993, and provides company-wide town-hall meetings three times a year.