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Salary: USD 155,000 - 210,000 / annual
Apex manufactures satellite buses at scale—the custom spacecraft platforms that hold customer payloads and enable earth observation, communications, and other critical missions. As a Senior Embedded Software Engineer on the Flight Software team, you will develop the low-level software that runs on custom avionics hardware powering these spacecraft.
You will own software from design through flight, working closely with avionics, GNC (guidance, navigation, and control), propulsion, and hardware engineers. Your responsibilities include:
- Developing low-level software that configures and drives processor peripherals and communication interfaces on avionics systems
- Writing and debugging device drivers for sensors, actuators, and components across the satellite bus
- Implementing onboard algorithms, including closed-loop control systems and fault detection/response logic (e.g., handling failed sensors or radiation upsets)
- Writing both rapid iterative code for bench and development testing, and rigorous, reviewed, flight-ready code for manufacturing
- Providing embedded software input into new system and hardware designs
- Supporting spacecraft commissioning during launch and early operations to ensure software systems remain functional during critical phases
Apex is a fast-growing, well-funded startup ($500M+ raised) focused on making commercial spacecraft accessible as launch costs decrease and payload demand increases. You'll work in a dynamic, fast-paced environment alongside aerospace and new-space experts, with real impact on humanity's access to space.
REQUIREMENTS:
- U.S. Person status required (ITAR/export control compliance)
- Bachelor's degree in CS, EE, or equivalent professional experience
- 3+ years writing C/C++ for embedded systems, ideally in spacecraft, robotics, automotive, or hardware interacting with the physical world
- Experience developing firmware for microcontrollers (bare-metal or RTOS)
- Experience writing and debugging low-level device drivers over SPI, I2C, UART, Ethernet, and CAN interfaces
- Comfort with hardware/software integration: reading schematics, using oscilloscopes and logic analyzers for hardware bring-up
- Solid understanding of microcontroller/microprocessor architecture (memory, buses, DMA)
PREFERRED:
- FPGA development experience
- Experience bringing up new avionics or flight hardware from first power-on
- Satellite attitude control systems (ACS) experience (reaction wheels, magnetorquers, thrusters)
- Motor driving, power electronics, or feedback sensor experience (encoders, current monitors)
- Familiarity with satellite systems and protocols (CCSDS, ECSS)
