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Apex manufactures satellite buses (spacecraft platforms) at scale for commercial space applications. The company combines software, vertical integration, and hardware design to enable reliable spacecraft across earth observation, communications, and other missions.
As a Senior Flight Software Engineer on the Flight Software team, you will design, develop, and own mission-critical software that brings spacecraft to life. You will tackle complex autonomous systems problems and build robust software enabling reliable 24/7 spacecraft operation across all mission phases. The Flight Software team comprises three interconnected groups: high-level application software, operating system software, and embedded software, with significant collaboration across teams.
Key responsibilities include:
- Design, develop, and own mission-critical satellite software throughout the full lifecycle: architecture, development, deployment, and operations
- Develop rapid iterative software for bench and development testing, plus rigorously reviewed and validated software for manufacturing and flight systems
- Plan and execute unit, integration, and system-level testing; diagnose and resolve defects to ensure quality, reliability, and performance
- Collaborate cross-functionally with systems, hardware, test, and operations teams to establish requirements, define technical roadmaps, and drive execution
- Support spacecraft commissioning during launch and early operations, troubleshooting software and maintaining critical flight system functionality
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), 15–20+ days vacation plus 10 paid holidays, 401(k) matching (100% on first 3%, 50% on next 2%), 8 weeks paid parental leave, daily catered lunch, and a collaborative Playa Vista office.
REQUIREMENTS:
- U.S. Citizenship (must possess ability to access export-controlled data)
- Active Top Secret clearance with SCI access and SAP eligibility
- 8+ years of total flight software experience
- Bachelor's degree in Computer Science, Electrical Engineering, or equivalent
- Strong proficiency in C++, Python, or Rust
PREFERRED:
- Experience developing, testing, deploying, and troubleshooting mission-critical satellite software from prototyping through flight operations
- Experience with real-time software on distributed hardware platforms across multiple satellite products
- Knowledge of embedded and real-time operating systems (Embedded Linux, Yocto, Buildroot, FreeRTOS, VxWorks)
- Experience writing and debugging low-level device drivers for hardware interfaces (SPI, I²C, UART, Ethernet, CAN, SpaceWire)
- Familiarity with satellite communication standards and protocols (CCSDS, ECSS)
- Familiarity with networking and secure communications (TCP/IP, UDP, TLS), data serialization (Protobuf, JSON, MessagePack), and encryption (AES, RSA)
- Experience translating requirements into technical solutions, defining technical roadmaps, and coordinating with cross-functional teams
- Experience supporting spacecraft commissioning during launch and early operations
- Experience with version control, configuration management, automated testing, and CI/CD pipelines
