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Salary: USD 185,000 - 210,000 / annual
Apex manufactures satellite buses at scale—the spacecraft platforms that hold customer payloads and enable earth observation, communications, and other critical missions. As a Senior Operating Systems Engineer on the Flight Software team, you will design, develop, and own the low-level software that brings these spacecraft to life.
You will tackle complex problems in autonomous systems and build robust, mission-critical software that enables reliable spacecraft operation 24/7 across every phase of a mission. Working closely with mission operations, GNC (guidance, navigation, and control), and hardware teams, you will architect new systems, prototype ideas, and deliver flight-ready code.
Key responsibilities include:
- Developing low-level software that configures and drives processor peripherals and communication interfaces on avionics
- Developing, configuring, and maintaining embedded Linux platforms and bootloader frameworks (Yocto, Buildroot, WolfBoot, U-Boot)
- Designing, implementing, and validating firmware update mechanisms, including bootloader integration, secure firmware deployment, and recovery procedures
- Designing and implementing security enhancements across complex software architectures to improve system integrity and resilience
The Flight Software team comprises three interconnected groups—high-level application software, operating system software, and embedded software—with significant collaboration and crossover. Experience in the space industry is not required; Apex seeks motivated engineers who enjoy solving complex problems, balance technical rigor with practicality, and thrive in a dynamic, fast-paced environment.
Apex is a fast-growing startup that has raised over $500M in funding. The company offers equity, comprehensive healthcare (100% company-paid medical, dental, vision), 15+ days vacation, 10 paid holidays, 8 weeks paid parental leave, 401(k) matching, catered lunch, and a collaborative Playa Vista office with flexibility for work-life integration.
REQUIREMENTS:
- U.S. Person status required (ITAR compliance for export-controlled data access)
- Bachelor's degree in CS, EE, or equivalent professional experience
- 8+ years writing code for operating systems, ideally Yocto or embedded Linux on spacecraft, robotics, automotive, or other hardware interacting with the physical world
- Strong proficiency in Python, C++, or Rust
PREFERRED:
- Experience developing, testing, deploying, and troubleshooting mission-critical satellite software from prototyping through flight operations
- Experience with embedded Linux platforms and bootloader frameworks (Yocto, Buildroot, WolfBoot, U-Boot)
- Experience bringing up new avionics and flight hardware from initial power-on through functional verification
- Experience with hardware/software integration, schematic analysis, and hardware debugging (oscilloscopes, logic analyzers)
- Familiarity with spacecraft attitude control systems (reaction wheels, magnetorquers, thrusters, sensors)
- Experience designing, implementing, and validating firmware update mechanisms with secure deployment
- Experience designing secure systems and implementing security enhancements in complex architectures
