Senior Principal Software Engineer – Core Services and Libraries

RTX

. Lead the architecture and design of core software components, libraries, and tooling aligned to avionics system requirements .

Posted 10/14/2026full-timeHuntsville • Alabama • United StatesSenior💰 $132,400 - $251,600 per yearWebsite

Core Competencies

Role fit

Core Competencies

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Demonstrates expertise in software architecture and design for avionics systems, with a strong focus on DO-178 certification processes and safety-critical software development. Proven ability to lead cross-functional teams and manage complex software requirements and verification activities.

Highest-signal resume keywords

DO-178 CertificationC++ DevelopmentSoftware Architecture DesignCross-Functional CollaborationSafety-Critical Software

ATS Keywords

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Applicant Tracking System Keywords

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Hard Skills

C++Software ArchitectureObject-Oriented DesignRequirements DecompositionTest Case DevelopmentAutomated Test ProceduresHigh-Level RequirementsLow-Level RequirementsFlight Management SystemsMiddleware Development

Soft Skills

Technical LeadershipCustomer EngagementStakeholder PresentationPeer Review ContributionQuality Assurance

Tools & Technologies

VxWorksGITSubversionJIRA

Certifications & Qualifications

DO-178 Certification

Industry Keywords

AerospaceSafety-Critical EnvironmentCivil CertificationDAL-A DeliverablesAvionics Systems

Tech Stack

Tools & technologies

SubversionC++

About the role

Key responsibilities & impact

Lead the architecture and design of core software components, libraries, and tooling aligned to avionics system requirements
Drive technical direction and execution across development and verification activities for safety-critical software under DO-178
Define and manage software requirements, decomposition, and traceability across complex systems
Develop and verify software using modern C++ and object-oriented design principles
Own and produce DO-178 certification artifacts, including DAL-A deliverables
Lead and support certification efforts, including engagement with customers and regulatory authorities
Conduct and contribute to peer reviews to ensure quality, consistency, and compliance across the lifecycle
Collaborate cross-functionally with engineering, program leadership, and customers to align technical solutions with program objectives
Contribute to the software foundation powering modern aircraft and scalable, certifiable avionics platforms

Requirements

What you’ll need

Degree in Science, Technology, Engineering or Mathematics (STEM) and minimum 10 years prior relevant experience, or an Advanced Degree in a related field and minimum 7 years of experience
Experience designing and developing software architecture, libraries, or platform-level components within an aerospace or safety-critical environment
Experience leading technical execution of projects, including customer engagement and presenting to senior stakeholders
Experience working across cross-functional engineering and program teams to deliver complex, integrated solutions
U.S. citizenship required; only U.S. citizens are authorized to access information under this program/contract
Experience with DO-178 software development and certification activities preferred
Experience with C++ and VxWorks preferred
Experience writing High-Level and Low-Level Requirements preferred
Experience writing Test Cases and Automated Test Procedures preferred
Experience with Civil Certification DO-178 – DAL A preferred
Experience with design and development of Flight Management Systems, Software, Aircraft Applications or Middleware preferred
Familiarity with revision control concepts and tools such as GIT, Subversion, and JIRA preferred
Willing and able to travel domestically and internationally as required, under 10%

Benefits

Comp & perks

Medical, dental, and vision insurance
Three weeks of vacation for newly hired employees
Generous 401(k) plan with employer matching funds and separate employer retirement contribution, including a Lifetime Income Strategy option
Tuition reimbursement program
Student Loan Repayment Program
Life insurance and disability coverage
Optional pet insurance, home and auto insurance, additional life and accident insurance, critical illness insurance, group legal, and ID theft protection
Birth, adoption, and parental leave benefits
Ovia Health, fertility, and family planning
Adoption Assistance
Autism Benefit
Employee Assistance Plan, including up to 10 free counseling sessions
Healthy You Incentives wellness rewards program
Doctor on Demand virtual doctor visits
Bright Horizons child and elder care services
Teladoc Medical Experts second opinion program
Relocation eligibility
Medical, dental, vision, life insurance, short-term disability, long-term disability, 401(k) match, flexible spending accounts, flexible work schedules, employee assistance program, Employee Scholar Program, parental leave, paid time off, and holidays
Potential annual short-term and/or long-term incentive compensation programs; payments are not guaranteed