Mechanical Test Engineer II

Vast is developing next-generation space stations and space infrastructure using an incremental, hardware-rich, and low-cost approach. Vast is rapidly developing its multi-module Haven Station to ensure a continuous human presence in space for America and its allies, enabling advanced microgravity research and manufacturing, and unlocking a new space economy for government, corporate, and private customers. Haven Demo’s 2025 success made Vast the only operational commercial space station company to fly and operate its own spacecraft. Next, Haven-1 is expected to become the world’s first commercial space station when it launches in 2027, followed by additional Haven modules. Additionally, the company recently announced Vast Satellite , a high-power satellite product line leveraging its space station components and the heritage of Haven Demo. Headquartered in Long Beach, California , and with more than 1,000 employees and over a billion dollars in private capital, Vast has built the facilities required to manufacture and operate America’s next space station. The company plans to develop future habitats and systems for the Moon and Mars, dedicated space stations for government partners, and other crewed systems that will unlock the expanding long-term space economy. Vast is looking for a Mechanical Test Engineer II , reporting to the Manager, Test Engineering , to support the development of the systems that will be required for the design and build of human-rated space stations. This will be a full-time, exempt  position located in our Long Beach location.  Responsibilities:  Design, build, and operate test rigs and GSE for ECLSS fluid, chemical, and electrical control systems, owning specific hardware test campaigns from setup through execution, data collection, and analysis Perform hands-on assembly, integration, instrumentation, and testing of ECLSS hardware spanning fluid systems, chemical subsystems, and electrical controls (pumps, valves, sensors, tubing, controls hardware) at operating pressures generally lower than thermal control test systems, including troubleshooting components and supporting root cause investigations of anomalies Develop and maintain test procedures, work instructions, and hardware-specific documentation, ensuring test traceability across planning, execution, and post-test data review Support Haven-1 flight hardware by contributing to Acceptance and Qualification Test Campaigns and conduct development/R&D testing on ECLSS module and CLD-derived hardware to inform design maturity and manufacturability Design test fixtures, wiring diagrams/schematics, and DAQ setups, and collaborate closely with ECLSS Manufacturing Engineers, Responsible Engineers (REs), Test Technicians, and the Controls and Automation team to ensure test setups reflect design intent and meet production-level testing needs Contribute to the team's transition from R&D-level testing toward standardized, production-ready test processes, provide technical input during test readiness reviews, and support continuous improvement efforts that boost test efficiency and data quality Minimum Qualifications: Bachelor's degree in Mechanical, Chemical, Aerospace, Electrical Engineering Hands-on experience with fluid and/or chemical systems, including fittings, valves, pumps, and sensors, with a working understanding of pressure systems Demonstrated ability to build, operate, and troubleshoot test rigs and hardware, from setup through data collection Ability to create test documentation — procedures and work instructions — and maintain test traceability from planning through execution Preferred Skills & Experience: CAD experience (e.g., Siemens NX) for reviewing designs and creating test/manufacturing documentation Programming experience (e.g., Python) for test automation and data analysis/review tools Prior hands-on experience building and managing test campaigns or hardware development from concept through execution Familiarity with Spacecraft Maximum Allowable Concentrations (SMACs) and their application to human-spaceflight air-quality assessment, contaminant control, and test-data interpretation Experience safely handling chemicals and executing chemical testing, including preparing solutions, operating relevant instrumentation, following SDS requirements, and managing chemical storage and waste disposal Additional Requirements: Willingness to work overtime, or weekends to support critical mission milestones Ability to lift up to 25lbs unassisted Pay Range: California $112,340 — $159,468 USD We calibrate level and compensation to the selected candidate's experience and demonstrated capability. We welcome applicants across a range of experience levels to apply. COMPENSATION AND BENEFITS Base salary will vary depending on job-related knowledge, education, skills, experience, business needs, and market demand. Salary is just one component of our comprehensive compensation package. Full-time employees also receive company equity, as well as access to a full suite of compelling benefits and perks, including: medical, dental, and vision coverage for employees and dependents, generous paid time off; up to 20+ days of vacation for exempt staff and up to 10+ days of vacation for non-exempt staff with the ability to cash-out unused vacation annually, paid parental leave, short and long-term disability insurance, life insurance, access to a 401(k) retirement plan, ClassPass credits, personalized mental healthcare through Spring Health, and other discounts and perks. We also take pride in offering exceptional food perks, with snacks, drip coffee & onsite barista, cold drinks, and dinner meals remaining free of charge, and lunch subsidized as part of Vast’s ongoing commitment to providing high-quality meals for employees. U.S. EXPORT CONTROL COMPLIANCE STATUS The person hired will have access to information and items subject to U.S. export controls, and the