Process Engineer
About the CompanyLightmill is building a new class of machine tools for manufacturing metal parts. We are an early-stage, engineering-driven startup based in San Francisco, working across lasers, robotics, software, and advanced manufacturing.About the RoleAs a Process Engineer at Lightmill, you will own the development, characterization, and optimization of our laser machining process. You will design experiments, analyze process data, establish operating windows, and translate fundamental observations into improvements in speed, accuracy, surface finish, material properties, and reliability. This is a highly hands-on role. You will spend significant time running machines, designing test articles, inspecting parts, diagnosing failures, and working directly with the mechanical, optical, and software systems that govern the process. You will collaborate closely with the founders and engineering team to develop new capabilities and prepare the process for deployment in commercial machines.ResponsibilitiesDevelop and optimize laser machining processes for aluminum, stainless steel, and future materials.Design and execute structured experiments relating process parameters to material removal rate, geometry, surface finish, dimensional accuracy, thermal effects, and material properties.Establish robust process windows and parameter sets across different materials, features, orientations, and part geometries.Investigate process failures, identify root causes, and develop practical corrective actions.Create test methods, fixtures, coupons, and measurement strategies for evaluating process performance.Analyze experimental and production data using statistical and computational tools.Work with software engineers to improve toolpath generation, process planning, parameter selection, and closed-loop control.Work with mechanical and optical engineers to identify hardware changes that improve process performance and reliability.Define process specifications, acceptance criteria, calibration procedures, and validation plans.Develop documentation that allows experimental processes to become repeatable machine operations.Support customer demonstrations, pilot parts, and the evaluation of new applications.Help build the technical foundation required to scale from prototypes to reliable commercial systems.QualificationsBachelor’s degree in mechanical engineering, materials science, manufacturing engineering, chemical engineering, applied physics, or a related field.Strong experimental instincts and experience designing controlled, quantitative tests.Hands-on experience developing or troubleshooting a physical manufacturing process.Ability to interpret dimensional inspection, microscopy, surface measurement, mechanical testing, or other process-characterization data.Experience using Python, MATLAB, JMP, Minitab, or similar tools for data analysis.Strong mechanical intuition and a practical approach to solving ambiguous technical problems.Ability to work independently in a fast-moving environment where equipment and processes evolve rapidly.Clear written communication and disciplined experimental documentation.Preferred SkillsExperience in one or more of the following areas is valuable but not required:Laser processing, laser micromachining, welding, additive manufacturing, EDM, CNC machining, or semiconductor processing.Design of experiments, statistical process control, process capability analysis, or manufacturing validation.Metallography, microscopy, profilometry, tensile testing, hardness testing, or dimensional metrology.Thermal modeling, heat transfer, fluid dynamics, debris management, or material-removal physics.Optical systems, galvos, motion-control systems, machine tools, or industrial automation.Developing manufacturing processes from early research through production release.What We ValueYou enjoy learning by building, testing, measuring, and iterating.You can move comfortably between scientific investigation and practical engineering.You are willing to operate imperfect prototypes and methodically make them better.You care about understanding why a process works, not simply finding a parameter combination that works once.You take ownership of difficult, open-ended problems.You are excited to help create an entirely new manufacturing process and machine-tool category.What We OfferFull-time employees are eligible for the following benefits listed below.An opportunity to shape the next generation of manufacturing technologyGrowth & Leadership Opportunities; Team members that take initiative are trusted with greater responsibilityMedical, dental insurancePaid holidays & Flexible time offLunch provided401(k) planLightmill offers competitive salary and equity, comprehensive benefits, and the opportunity to work alongside a small, highly technical team in San Francisco.