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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Test Engineer, HITL - **Company:** Observable - **Location:** Los Angeles, CA, United States (Remote available) - **Experience:** Expert - **Contract:** Permanent contract - **Skills:** Board Bringup, C (Programming Language), Test Suite, Adobe InDesign, Application Programming Interfaces (APIs), Automation of Tests, C++ (Programming Language), Cloud Computing, Code Coverage, Communications Protocols, Computer Maintenance, Computer Programming, Continuous Delivery, Continuous Integration, Software Debugging, Distributed Systems, Linux on Embedded Systems, Ethernet, Firmware, Hardware Design, Hardware Interface Design, Hardware-In-The-Loop Simulation, Iterative and Incremental Development, Python (Programming Language), Open Source Technology, Real-Time Operating Systems, Software Engineering, Software Systems, Verification and Validation (Software), System Testing, Systems Integration, Universal Asynchronous Receiver/Transmitter, Visual Systems, Digital Twin, Scripting, Serial Peripheral Interface, Real Time Systems, Reliability of Systems, System-level Testing, Computer Equipment, Information Technology - **Published:** September 2, 2026 - **Apply:** https://www.careerbuilder.com/job-details/sr-test-engineer-hitl-los-angeles-ca--a35a441f-727a-4176-aa1d-4e4ae23535eb ## About the Role * 5+ years of experience in test engineering, embedded systems, or systems-level development. * Strong programming skills in C/C++, Python, or similar languages used for test automation and system integration. * Experience designing and implementing hardware-in-the-loop (HIL/HITL) or system-level test environments. * Solid understanding of embedded systems, hardware interfaces (I2C, SPI, UART, CAN, Ethernet), and real-time systems. * Experience using lab instrumentation (oscilloscopes, logic analyzers, multimeters, etc.) for debugging and validation. * Ability to read schematics and debug issues at the electrical-software boundary. * Strong debugging mindset and ability to diagnose complex, cross-disciplinary issues. * Experience working in fast-paced, iterative development environments. * Strong communication and collaboration skills across engineering disciplines., * Experience with spacecraft, aerospace systems, robotics, or other high-reliability environments. * Familiarity with embedded Linux, RTOS, or firmware development workflows. * Experience building simulation environments or digital twins for system validation. * Knowledge of communication protocols and telemetry systems used in distributed or remote systems. * Experience with CI/CD pipelines and automated test infrastructure for hardware-integrated systems. * Background in vision systems, sensors, or control systems. * Experience with environmental testing (thermal, vibration, vacuum) and validation workflows. * Contributions to open-source testing frameworks or embedded systems projects. * Passion for astronomy, physics, and scientific exploration., Aerospace and Defense, Application Programming Interface (API), Astronomy, Benchmarking, C Programming Language, C++ Programming Language, Cloud Computing, Communication Skills, Communications Protocols, Computer Firmware, Computer Hardware, Computer Maintenance, Computer Programming, Computer Systems, Construction, Continuous Deployment/Delivery, Continuous Integration, Control Systems, Debugging Skills, Distributed Computing, Electricity, Embedded Hardware, Embedded Linux, Embedded Systems, Ethernet, Hardware Administration, Hardware Design, Hardware Quality Assurance, Hardware Simulation, Hardware-Software Integration, High Reliability, I2C, Identify Issues, Injections, Instrumentation, Laboratory, Laser Communications, Logic Analyzer, Manufacturing, Open Source, Optics, Oscilloscope, Physics, Product Lifecycle, Product Testing, Python Programming/Scripting Language, RTX, Realtime Operating System, Robotics, Simulation, Software Engineering, System Integration (SI), System Test, System Validation, Systems Maintenance, Systems Reliability, Team Player, Telemetry, Test Automation, Test Design, Test Harness, Test Plan/Schedule, Test Suite, Test Tools, Testability, Testing, Universal Asynchronous Receiver-Transmitter (UART), Validation Plan, Validation Testing ## Description As a Senior Test Engineer, HITL, you will work across our full product line, from robotic ground-based telescope systems to future on-orbit platforms. You will design, build, and operate hardware-in-the-loop (HITL) test systems that validate the performance, reliability, and integration of our hardware and software systems. This role is deeply hands-on: you will interface directly with real hardware, develop automated test frameworks, simulate real-world and space environments, and debug complex issues across electrical, mechanical, and software boundaries. You will report to the Systems or Embedded Engineering Lead. What You'll Do * Architect, implement, and maintain hardware-in-the-loop (HITL) test systems for validating spacecraft and telescope subsystems. * Design test infrastructure that integrates real hardware with simulated environments (sensors, actuators, communication links, and control systems). * Develop automated test frameworks and tooling to enable scalable, repeatable validation across the product lifecycle. * Build and maintain simulation environments for system-level testing, including fault injection and edge case validation. * Collaborate closely with embedded, electrical, mechanical, and software teams to ensure comprehensive system verification. * Debug complex system-level issues across hardware and software boundaries, including real-time and edge-case failures. * Define and execute test plans, validation procedures, and performance benchmarks for integrated systems. * Support hardware bring-up, integration, and system-level validation activities. * Contribute to CI/CD pipelines by integrating automated test suites and ensuring test coverage across releases. * Participate in design reviews (PDR, CDR, etc.) to ensure testability, reliability, and system robustness. ## Related Videos - [Excellent Software Testing](https://www.wearedevelopers.com/videos/87-excellent-software-testing) - [JavaScript? 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