Senior Flight Software Engineer

SerenX is building the next generation of portable, autonomous defensive missile systems to protect America and our allies. We're making advanced air defense smaller, more affordable, and accessible to the people who need it.

We're an institutionally funded defense technology company performing work on U.S. Department of Defense contracts. Our founding team includes Y Combinator alumni, former Special Operations leaders, and experienced aerospace engineers.

We believe in small engineering teams with real ownership. We design, build, test, fly, break things, learn, and build again.

A variety of soft skills and experience may be required for the following role Please ensure you check the overview below carefully.

We're hiring a Senior Flight Software Engineer to join our founding engineering team and own the real-time embedded software that controls our SX family of missiles.

You'll develop a modern, proprietary C++ flight-software architecture, transitioning from our existing flight-control stack to a clean, modular implementation on ARK Electronics flight-computer hardware.

This is software that directly interfaces with sensors, estimates vehicle state, executes control loops, commands actuators, and keeps flight hardware operating reliably.

You'll work directly with flight computers, oscilloscopes, debuggers, CAN traces, and real flight hardware. You'll write software, prove it on the bench, and take it to the test range.

Location: Melbourne, FL - On-site

Employment: Full-time

Compensation: $145,000–$180,000 + equity

Reports to: CTO

• Architect, implement, and maintain real-time embedded flight software in modern C++.
• Develop low-level hardware interfaces, sensor drivers, actuator controls, and vehicle communication systems.
• Implement and maintain attitude/rate control, state estimation, control allocation, vehicle modes, and flight-safety logic.
• Establish deterministic execution, scheduling, latency budgets, fault handling, and watchdog behavior on resource-constrained hardware.
• Design reliable interfaces between the flight computer and our NVIDIA Jetson-based mission/autonomy computer.
• Build modular hardware abstraction layers and reusable flight-software components that support future vehicle platforms.
• Develop telemetry, flight logging, instrumentation, and diagnostics to make flight behavior observable and reproducible.
• Build rigorous verification infrastructure using unit tests, simulation, software-in-the-loop (SIL), hardware-in-the-loop (HIL), fault injection, and flight-log replay.
• Own embedded build systems, firmware deployment, version control, continuous integration, and reproducible flight-software releases.
• Work alongside mechanical, electrical, controls, and test engineers during bench testing, integration, hover, and full flight testing.
• Diagnose real-world failures, identify root causes, implement fixes, and personally validate the results on hardware.

• 6+ years of embedded or real-time software engineering experience, with substantial C or C++ development on physical hardware. Exceptional candidates with less experience but unusually strong systems ownership are welcome.
• Deep proficiency in modern C++, memory management, concurrency, synchronization, debugging, and embedded systems architecture.
• Experience with embedded Linux, RTOS, or bare-metal development, including cross-compilation, drivers, hardware bring-up, and deployment.
• Experience developing software for real-time control systems, avionics, robotics, autonomous vehicles, motor control, or similarly demanding physical systems.
• Understanding of feedback control, IMUs, state estimation, sensor fusion, filtering, timing, and actuator interfaces.
• Experience with CAN, DroneCAN/UAVCAN, serial communications, telemetry, or other embedded vehicle networks.
• Strong troubleshooting skills and the ability to diagnose problems across the software, electronics, and physical system.
• Degree in Computer Engineering, Computer Science, Electrical Engineering, Aerospace Engineering, or a related discipline, or equivalent demonstrated engineering experience.
• Ability to work on-site in Melbourne, Florida and participate directly in hardware integration and field testing.

• Development or significant modification of ArduPilot, PX4, or other flight-control software.
• ARM Cortex, STM32, ARK Electronics, Pixhawk/Cube, ChibiOS, NuttX, FreeRTOS, Zephyr, or comparable embedded platforms.
• Flight-control algorithms, attitude/rate loops, EKF estimation, thrust vector control