Infleqtion is seeking a system-level mechanical engineer to design the infrastructure, mounting, and environmental-survivability architecture that allows our Quantum Gravity Gradiometer (QGG) to transition from the laboratory to both terrestrial and space environments. In this role, the candidate will work the structural mounting, damping, isolation, thermal interfaces, and mechanical integration needed for the QGG sensor head to survive launch, handling, transport, and pre-launch microgravity testing while preserving the precision required for quantum measurement. The role requires close collaboration with our prime customer(s), internal management, researchers, systems engineers, optical and electrical engineers, aerospace experts, manufacturing partners, suppliers, and external contractors. The individual will actively engage customers and partners throughout the program lifecycle, ensuring delivery against milestones and commitments while maintaining alignment with Infleqtion's product lifecycle and quality standards. Cross-disciplinary engagement is expected, with this role driving technical alignment across mechanical, optical, electrical, systems, and mission domains. Job Responsibilities The duties and responsibilities outlined below include essential functions of the role. Depending on business needs, this role may perform a combination or all of the following duties. Duties, responsibilities, and activities may change, or new ones may be assigned. • Together with other mechanical engineers, complete the design of the QGG sensor head and associated hardware so it can operate in development and microgravity test environments as well as terrestrial and space applications. This includes making disciplined trades among structural dynamics, thermal performance, optical alignment stability, magnetic cleanliness, mass, packaging, manufacturability, and quantum-sensor performance. • Present progress, analyses, risks, design decisions, and test results to senior management, design-review boards, and the end customer. • Execute and direct the modeling, simulation, analysis, and test-correlation efforts required to enable product performance, including structural, thermal, modal, vibration, shock, and tolerance analysis as appropriate. • Responsible for the mechanical integration of sensor-head subsystems with optical, electrical, vacuum, thermal, fiber, cable, and external spacecraft or ground-test interfaces. • Identify, qualify, and technically manage key suppliers for precision machined parts, opto-mechanical hardware, isolation/damping hardware, specialty materials, and manufacturing processes. • Follow Infleqtion's Product Lifecycle Process and support phased gate reviews, design reviews, configuration control, build readiness, environmental test readiness, and executive updates. • Develop and maintain mechanical risk-management and risk-resolution plans; support reliability analysis, nonconformance resolution, lessons learned, and continuous improvement. • Coach and mentor junior engineers in practical mechanical design, drawing quality, tolerance analysis, build discipline, and design-for-manufacturability/test. • Other duties as assigned or required Requirements Minimum Qualifications • Bachelor's degree required in mechanical engineering, aerospace engineering, or a closely related engineering discipline. • 6+ years of relevant and progressive experience in precision mechanical, opto-mechanical, aerospace, or high-reliability hardware roles. • Demonstrated expert-level proficiency in SolidWorks CAD design tools, including parts, assemblies, drawings, and configuration control. • Excellent proficiency in first-principles mechanical engineering, including load paths, stiffness, thermal expansion, tolerancing, materials, and design trade studies. • Experience using SolidWorks Simulation or comparable structural/thermal analysis tools; ability to interpret results and correlate analyses with hardware test. • Excellent technical leadership and collaboration skills, with the ability to drive decisions across mechanical, optical, electrical, systems, and manufacturing teams. • Advanced understanding of opto-mechanics, including free-space optical mounting, collimation, free-space and fiber-coupled alignment, flexures, and alignment/tolerance stability through build and environmental test. • Demonstrated DFx experience: design for cost, manufacturing, assembly, test, reliability, and serviceability. • Understanding of ASTM E595 and practical material selection for vacuum and space environments, including outgassing, thermal expansion, contamination, corrosion, and non-magnetic constraints. • Experience designing custom flexure mounts, precision optical/instrument mounts, or passive isolation/damping features. • Demonstrated tolerance analysis and tolerance-stack-up experience for precision assemblies. • Hands-on engineer with experience building, debugging, and improving engineering-development and flight- or production-intent hardware. • Uses AI appropriately for engineering leverage while understanding the limitations of current platforms and maintaining independent technical judgment and verification. • Ability to travel domestically and (potentially) internationally up to 10% Desired Qualifications • Comfortable with a hands-on engineering-leadership approach, including time in the lab, supplier discussions, integration, and environmental test. • Master's or PhD degree in aerospace, mechanical engineering, or related field. • Experience delivering advanced technologies to commercial, civil, defense, or space markets, ideally through formal design review and environmental verification. • Experience in hardware DFx (design for cost, manufacturing, assembly, test, sustainment) and supplier technical management. • Familiarity with quantum sensing, atomic physics, precision optics/photonics, vacuum systems, or high-stability inertial/gravity instrumentation. Benefits • 100% company-paid medical, dental, vision, short/long-term disability • Employer-funded Health Savings Account • Unlimited PTO • 401(k) match • Company-paid Life and AD&D Insurance • Flexible Savings Account • Paid FMLA, Maternity/Paternity Leave • Employee Assistance Program • Student Loan Repayment • Equity Program