Principal​/sr Principal Software Engineer, Flight Software Software

Principal/sr Principal Software Engineer, Flight Software

Lead design and deployment of flight software for space systems

Centennial, Colorado, United States

Pay Range: $184,628 - $253,884 per year.

Your actual base compensation will be determined on a case‑by‑case basis and may vary based on job‑related knowledge and skills, education, experience, internal equity and market competitiveness.

At Sierra Space, we build the missions and systems that keep our world secure in the domain above Earth.

Sierra Space team members share a spirit of innovation and collaboration and a belief that we can deliver on the boldest missions in space today. Together with our customers, we aim to safeguard our nation, sustain human presence in space, and secure the freedom of operations in low Earth orbit and beyond.

Our success is measured by the trust of those who rely on what we build and deliver, and our technologies keep the United States and its allies mission‑ready throughout space.

We are mission‑driven, and together, we are an extraordinary team.

The Principal Software Engineer role involves designing, developing, and testing software applications for space systems and technologies. This advanced position requires extensive expertise in multiple programming languages, an advanced understanding of software development principles, and the ability to design, architect, and implement complex software systems. The role includes writing clean, maintainable code, collaborating with team members to understand project requirements, and contributing to the development of innovative software solutions.

Additionally, this position requires a deep understanding of software engineering processes, advanced algorithmic knowledge, and system scalability. The role also involves providing technical leadership and mentorship to other engineers.

• Requires bachelor's degree in a related field (or equivalent work experience in lieu of degree or master's +10 yrs experience).
• Typically, 12+ years of related experience.
• Extensive expertise in multiple programming languages and software development principles.
• Ability to design, architect, implement, and test complex software systems.
• Expert understanding of software engineering processes, advanced algorithmic knowledge, domain‑specific design patterns, performance tuning, and system scalability.
• Mastery in writing scalable, optimized code, ability to design complex software systems, and knowledge of best practices, including secure coding, and system architecture principles.
• Ability to independently contribute to the design and development of software applications, conduct unit tests, and participate in code reviews.
• Experience with different software development methodologies such as Agile and Scrum/Kanban.
• The ability to obtain and maintain a U.S. Security Clearance is required.

• Expert‑level proficiency in C++ and Object‑Oriented Programming, with a strong ability to design and implement complex software architectures.
• Extensive experience designing and implementing client‑server applications using socket I/O with TCP/UDP protocols.
• Proven expertise in developing loosely coupled, scalable applications leveraging PUB/SUB messaging frameworks.
• In‑depth knowledge of open standards such as CCSDS, C2MS, Open Mission Systems (OMS), and Universal C2 Interface (UCI), with experience integrating these standards into software solutions.
• Comprehensive experience in spacecraft flight software development, including real‑time systems and fault‑tolerant architectures.
• Significant experience developing mission management and/or payload control software for complex systems.
• Demonstrated ability to lead cross‑functional software development teams, effectively managing timelines, deliverables, and technical challenges.
• Advanced experience utilizing software tools for requirements tracking, code reviews, static analysis, artifact repositories, and automated build pipelines.
• Deep understanding of software development methodologies, including Agile/Scrum, and the ability to mentor teams in their adoption and execution.
• Strong…