Mechanical Engineer , Powertrain

About Tau Power conversion is the bottleneck between the compute, energy, and mobility industries and the future they're trying to build. Most of the industry is still solving it with decades-old approaches. Tau is fixing that. We're a venture-backed hardtech company in Redwood City, building power conversion technology for data centers, EVs, and energy systems. Several products are already moving into production. We hire people who own problems end-to-end: power electronics, embedded software, controls, test and validation, mechanical design. We solve from first principles, not legacy playbooks. We're past "promising technology." Customers are buying, volume is coming, and the people who join now set the standard everyone builds on after. Who you are You're practical, not precious about your own ideas. You'll defend a design decision with data, and drop it just as fast when better data shows up. You understand that automotive standards aren't a formality. Qualification, reliability, and durability requirements exist because failure in the field is expensive and dangerous, and you treat them as real constraints, not checkboxes to satisfy on the way to the interesting part. You communicate problems before they become surprises. If a program is off track, you say so immediately with enough details that someone can act on it. Silence is the failure mode here, not an honest "this is behind" Our Engineering Approach Solve customer problems, not engineering puzzles. Great technical work becomes exceptional when it creates reliable products, enables meaningful new capability, and solves real customer problems. Think in systems. Understand how your work affects the complete product and the people who build it. Make tradeoffs that improve the whole, not just your direct area of ownership. Exercise judgment. Apply the engineering rigor the risk requires. Make timely decisions with the available evidence, communicate uncertainty, and balance technical excellence with program needs. Raise the standard. Deliver quality work on time, improve how the team works, and leave the products, systems, tools, and people around you better than you found them. About the role This role is about taking mechanical designs to automotive-grade production. The bar is qualification: will this pass, will it hold up over the life of the vehicle, will it manufacture repeatably at volume. The schedule is real, and so are the consequences of missing it. You'll understand the spec, including automotive qualification requirements, deliver against it, and say something the moment it's at risk. If a design won't hold up under vibration testing, or a supplier is slipping, we want to know at week one, not week six. Good design and fast delivery aren't in tension here. We just don't reward cleverness that doesn't serve the spec. You'll have real input into design decisions and pushback rights when a spec seems wrong; this isn't execution-only. But if you'd rather defend your own solution than hit what the program actually needs, this isn't your seat. We're open to a range of seniority, including someone who could eventually run the team. Seniority isn't the bar. Competence is: do you consistently deliver what you said you would, communicate clearly the moment you can't, and stay focused on what the program needs over what's interesting to you personally. Because our success depends on collaboration, we expect new employees to work onsite five days a week to build strong working relationships with the team. Areas of ownership Mechanical design Lead mechanical integration of electric machines and powertrain hardware: rotors, stators, housings, shafts, bearings, cooling systems, structures, enclosures, interfaces Weigh in on design decisions and specs, not just execute against them Produce clear models, drawings, and specifications that others can build from without guessing Analysis and validation Own DVP/DVP&R that connects requirements, including automotive qualificati…