Hermeus is a venture-backed defense aviation company reclaiming the lost art of rapid iterative prototyping to build the fastest aircraft in the world today. By prioritizing relentless hardware iteration, we deliver high-speed systems at the pace of the modern battlefield. We work with the Department of War to provide the high-speed capabilities our nation and its allies need to maintain a durable, asymmetric advantage.      About The Role: We are seeking a highly motivated and experienced Senior Software Simulation Engineer to join Hermeus, a hypersonic aircraft startup company. As a Senior Software Simulation Engineer, you will be responsible for developing and deploying real-time simulation environments that support the design, verification, and validation of aerospace flight control and avionics systems. Leveraging Model-Based Design (MBD) principles, you will use MATLAB/Simulink and automated code generation tools to translate dynamic system models into executable real-time code for Hardware-in-the-Loop (HIL) and Software-in-the-Loop (SIL) testing.    This role bridges the gap between control system design and embedded software implementation, ensuring accurate representation of aircraft dynamics and system behavior under simulated flight conditions. You will collaborate with multidisciplinary teams to integrate models with real-time targets, optimize simulation performance, and contribute to the certification and reliability of flight-critical systems.    Ideal candidates will have a solid understanding of aerospace systems, control theory, and real-time simulation platforms, along with hands-on experience in model-based code generation, HIL development, and test automation within safety-critical environments. Responsibilities • Develop and maintain real-time simulation environments for flight control, avionics, and aircraft systems. • Build and support SIL and HIL test environments for flight software verification. • Use MATLAB/Simulink and Model-Based Design workflows to create models and generate real-time code. • Integrate aircraft dynamics, controls, sensors, actuators, and avionics models into simulation environments. • Connect models with real-time targets, embedded software, and hardware interfaces. • Improve simulation performance, timing, fidelity, and reliability. • Create automated test scripts and tools to support repeatable validation. • Work closely with GNC, flight software, avionics, systems, and test teams to debug and validate system behavior. • Support documentation, requirements traceability, and verification activities for flight-critical systems. Requirements: • Bachelor’s degree in Aerospace Engineering, Electrical Engineering, Computer Engineering, Computer Science, Mechanical Engineering, or related field. • 5+ years of experience in simulation, controls, embedded software, or real-time test environments. • Hands-on experience with MATLAB, Simulink, and Model-Based Design. • Experience with code generation tools such as Simulink Coder or Embedded Coder. • Understanding of aircraft dynamics, control systems, avionics, or embedded aerospace systems. • Experience with SIL, HIL, or real-time simulation environments. • Proficiency in C/C++, Python, or similar programming languages. • Strong debugging skills across software, models, and hardware interfaces. • Ability to work across teams in a fast-paced engineering environment Preferred Skills and Experience: • Experience with real-time platforms such as Speedgoat, dSPACE, NI VeriStand, or OPAL-RT. • Experience supporting flight controls, GNC, avionics, autonomy, or aircraft systems. • Familiarity with interfaces such as CAN, Ethernet, ARINC 429, MIL-STD-1553, RS-422, or serial. • Experience with automated testing, CI/CD, Git, or software configuration management. • Familiarity with safety-critical aerospace standards such as DO-178C, DO-331, or DO-254. • Experience integrating simulation environments with flight software or test hardware. • Background in aircraft, UAVs, spacecraft, defense systems, or other complex aerospace platforms. • Strong ownership mindset and ability to build practical tools that help teams test and iterate quickly. The salary range listed for this role is intended as a general guideline. Final compensation will be determined based on a variety of factors, including role scope and responsibilities, relevant experience, education and training, key skills, market data, and business needs. At Hermeus, compensation is only one part of our total rewards package. We offer competitive pay, equity, and a range of benefits designed to support our team. Benefits: Health & Wellness: 100% employer-paid healthcare and pet insurance Financial: Competitive pay, stock options, 401(k) retirement plan, and potential year-end bonuses Time Off: Paid parental leave, 12 federal holidays, unlimited PTO for exempt employees, and generous accrued PTO for non-exempt employees Office Perks: Weekly paid office lunches and fully stocked breakrooms   U.S. EXPORT CONTROL COMPLIANCE STATUS  The person hired will have access to information and items subject to U.S. export controls, and therefore, must either be a “U.S. person” as defined by 22 C.F.R. § 120.62 or otherwise eligible for deemed export licensing. US persons include U.S. citizens, U.S. nationals, lawful permanent residents (green card holders), and asylees and refugees with such status granted, not pending.    EQUAL OPPORTUNITY Hermeus is an Equal Opportunity Employer. Employment decisions at Hermeus are based solely on merit, competence, and qualifications, without regard to race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability, or any other legally protected status. #LI-JC3