Avionics Hardware Engineer

Company: Castelion
Location: Torrance, CA (in office 5 days per week)
Compensation: $150,000 - $200,000 + competitive equity
Employment Type: Full-time
Visa Sponsorship: Not available (US citizens and green card holders)

Castelion is a modern defense production company building long-range hypersonic strike systems to close a critical national security gap. Founded in 2021 under a philosophy of "peace through deterrence," it is one of the few hypersonics companies to move beyond concepts to production, with active government contracts including a $23M+ Navy order for 50 units delivering in 2027.

Castelion has raised $1B+ through its Series C.

Castelion is hiring Avionics Hardware Engineers (3-8 years) to own mission-critical flight hardware end to end. You will design complex mixed-signal, high-speed PCBs from architecture and requirements through schematic design, component selection, bring-up, debugging, verification and vehicle integration. The avionics are the brain of the missile system, and with 15+ boards in development, each engineer owns meaningful subsystems that directly affect flight success.

• Own the full design lifecycle of circuit card assemblies: requirements, schematics, PCB layout, bring-up, debugging and qualification.
• Design mixed-signal, high-speed boards with processors, memory, Ethernet, power electronics, sensor/actuator interfaces and backplanes.
• Work with supply chain on component selection, ordering and supplier relationships.
• Test and verify hardware against requirements and iterate on designs.
• Integrate qualified hardware into the vehicle and support production readiness.

• 3-8 years of hardware/PCB design experience
• Mixed-signal and high-speed digital board design through bring-up and qualification
• Altium Designer or Cadence Allegro
• Power electronics experience
• US citizenship or green card (defense work)
• Ability to work on-site in Torrance 5 days a week

Altium Designer, Cadence Allegro, PCB design, mixed-signal and high-speed digital design, power electronics, schematic capture, Python