HITL Engineer

At Relativity Space, we’re building rockets to serve today’s needs and tomorrow’s breakthroughs. Our Terran R vehicle will deliver customer payloads to orbit, meeting the growing demand for launch capacity. But that’s just the start. Achieving commercial success with Terran R will unlock new opportunities to advance science, exploration, and innovation, pioneering progress that reaches beyond the known.

Joining Relativity means becoming part of something where autonomy, ownership, and impact exist at every level. Here, you're not just executing tasks; you're solving problems that haven’t been solved before, helping develop a rocket, a factory, and a business from the ground up. Whether you’re in propulsion, manufacturing, software, avionics, or a corporate function, you’ll collaborate across teams, shape decisions, and see your work come to life in record time. Relativity is a place where creativity and technical rigor go hand in hand, and your voice will help define the stories we’re writing together. Now is a unique moment in time where it’s early enough to leave your mark on the product, the process, and the culture, but far enough along that Terran R is tangible and picking up momentum. The most meaningful work of your career is waiting. Join us.

About the Team:

The Interplanetary Sciences Program is building a philanthropically funded Mars science orbiter targeted to launch in 2028. You will build the integrated hardware-in-the-loop (HITL) test capability that allows the spacecraft team to test early, continuously, and with real hardware. Then carry that ownership into final spacecraft integration and test leading up to flight.

This is a hands-on integration and test role spanning hardware, software automation, and spacecraft-level validation. You will take the HITL environment from an empty rack to a running, automated, always-on validation system that proves our payloads, avionics, flight software, and interfaces work together as intended.

You will build the bench, the software fixturing that exercises flight software against real and representative hardware, and the CI and regression infrastructure that continuously checks the system as it evolves. You won't just execute test procedures—you'll understand what each test proves, why it matters, and whether the result is actually credible.

You will work shoulder to shoulder with engineers across the spacecraft. If you like owning a capability end to end, debugging across hardware and software boundaries, and being the reason the rest of the program can move quickly with confidence, this is that seat.

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About the Role:**

• Design, build, and maintain the ISP HITL test environment end to end, including rack fabrication, avionics installation, breakout hardware, load emulation, harness fabrication and routing, and supporting test equipment.
• Build the simulation, data-acquisition, and control infrastructure that drives stimulus into the system, captures results, and allows flight software to be exercised against real and representative spacecraft hardware.
• Develop software fixturing, automated test frameworks, and CI/regression pipelines that validate every software change on hardware with automated pass/fail adjudication, regression detection, and clear failure reporting.
• Debug integrated failures across flight software, avionics, interfaces, harnessing, timing, communications, and test infrastructure until root cause is understood and fed back to the responsible design teams.
• Validate timing-sensitive behavior and interfaces across sensors, actuators, payloads, avionics, and communication buses, including longer-duration and soak testing where appropriate.
• Establish dashboards, telemetry views, configuration control, and test procedures that make system health, test coverage, anomalies, and requirements traceability clear to the broader engineering team.
• Drive final integration and test of flight hardware leading into launch, coordinating with subsystem responsible engineers to ensure hardware and software are designed for integration and test from the beginning.

About You:

• Degree in computer, electrical, aerospace, or a related engineering field, or equivalent hands-on experience
• 7+ years of experience in test engineering, including architecting automated test frameworks for integrated hardware, firmware, and software systems
• Strong, current software skills for test automation, tooling, and validation pipelines
• A track record of building test automation and CI/regression infrastructure from the ground up, including telemetry/logging, automated pass/fail, and continuous test execution
• Hands-on hardware and embedded systems experience, including bench troubleshooting with standard electronics equipment and familiarity with interfaces such as Ethernet, UART, and SPI
• Demonstrated ability to own a complex test capability end to end, drive integrated hardware/software failures to root cause, and coordinate effectively across engineering teams

Nice to haves but not required:

• Experience standing up a test bench, HITL system, SIL/HIL environment, lab automation capability, or integrated test platform from scratch
• Experience with spacecraft, launch vehicles, satellites, robotics, autonomous systems, aircraft, vehicles, medical devices, industrial equipment, or other high-reliability hardware
• Hands-on experience with harnessing, cable fabrication, breakout boards, rack wiring, or test equipment setup
• Experience helping establish test practices, tools, or team processes in a fast-moving engineering environment

At Relativity Space, we are committed to transparency and fairness in our compensation practices. Actual compensation will be determined based on experience, qualifications, and other job-related factors.

Compensation is only one part of our total rewards package. Relativity Space offers competitive salary and equity, a generous PTO and sick leave policy, parental leave, an annual learning and development stipend, and more! To see some of the benefits & perks we offer, please visit here.

Hiring Range:$164,000—$246,000 USD

We are an equal opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.

If you need a reasonable accommodation, please contact us at accommodations@relativityspace.com.

Please note: Relativity Space does not accept unsolicited resumes, candidate profiles, or referrals from recruitment agencies or search firms. Any unsolicited submission - via email, our website, social media, or directly to an employee - will be deemed the property of Relativity Space, and no fee will be owed absent a current, fully executed agreement with Talent Acquisition that specifically authorizes submissions for the applicable role.