We are looking for an Avionics Hardware Engineer with 3-8 years of experience to own mission-critical flight hardware end-to-end at a rapidly scaling hypersonics company. You'll be responsible for designing complex mixed-signal, high-speed PCBs — taking them from architecture and requirements through schematic design, component selection, board bring-up, debugging, verification, and vehicle integration. The avionics hardware is the brain of the missile system, and with 15+ PCBs in development, each engineer owns meaningful subsystems that directly impact flight success. This is an opportunity for a true builder who thrives on full design cycle ownership in a technically demanding, high-velocity environment.
What will you be doing?
Castelion is a modern defense production company building long-range hypersonic strike systems to address a critical national security gap. Founded in 2021, Castelion was created in response to the recognized need for the United States to rapidly develop hypersonic capabilities to remain competitive with near-peer adversaries and deter future conflicts.
The company operates under the philosophy of "Peace through Deterrence" — building the weapons systems that ensure conflicts never need to happen. Castelion is one of the few companies in the hypersonics space that has moved beyond concepts to actual production deliverables, with government contracts across multiple branches of the military and a $23M+ Navy order for 50 units in calendar year 2027.
Backed by over $469M in funding from top-tier investors including Andreessen Horowitz, Lightspeed Venture Partners, and General Catalyst, Castelion is scaling rapidly. The company is building what it anticipates will become the preeminent hypersonics campus in the country — including a $150M, 1,000-acre solid rocket motor manufacturing facility in Rio Rancho, New Mexico, alongside its headquarters in Torrance, California.
Castelion's culture is defined by technical excellence, ownership, and velocity. Engineers own meaningful subsystems on the vehicle and are responsible for driving their success. The company follows a responsible engineering model inspired by SpaceX, where individuals choose the highest-value work and are empowered to cultivate resources and partnerships to deliver results. The engineering bar is exceptionally high — attracting elite talent who want to be surrounded by other elite talent.
Senior Avionics Test Engineer
Senior Power Electronics Engineer
Senior Control Electronics Engineer
Lead Integration & Test Engineer
Tooling Engineer
Salary
$150,000 - $200,000
Location
Torrance, United States
Experience
3+ years
Total raised
$464M
Last stage
Growth
Investors
No applications, no recruiter spam. Just the intro.
A few questions to make sure this role is the right shape for you. Two minutes.
I write the intro, send it to the founder, and handle the back-and-forth.
If they’re a yes, I book the chat. You show up — that’s the whole job-hunt.