Director of Mechanical Engineering

About the role

You will own a significant portion of the mechanical organization's active initiatives and provide leadership for a substantial portion of the engineering team. This position is focused on the design, validation, and delivery of critical mechanical subsystems that form the foundation of our distributed power platform. You will be responsible for translating high-level system requirements into detailed mechanical architectures and ensuring robust integration across hardware disciplines. The role demands a balance of hands-on technical depth and the ability to set direction for a growing and complex engineering organization. You will operate at the intersection of first-principles physics and practical manufacturing constraints to de-risk our core technology. Your leadership will be instrumental in establishing the technical standards and processes that allow our hardware to scale reliably. You will partner closely with leaders across engineering, operations, and product to align mechanical strategy with business objectives. This is a pivotal role in defining the mechanical foundation of Mainspring's next-generation power systems.

Key facts

What you'll do

Lead the mechanical architecture and system integration for the Linear Generator platform, defining how core subsystems interact as a unified product.

Own the design and execution strategy for a portfolio of 50+ active mechanical initiatives, setting priorities and managing trade-offs across performance, cost, and schedule.

Provide technical leadership for critical subsystems including reciprocating pressure-driven assemblies, air-spring return chambers, precision alignment systems, and linear electromagnetic machines.

Establish and maintain mechanical engineering standards, validation methods, and design controls to ensure reliability, scalability, and manufacturability.

Drive the development of detailed mechanical designs, from early concept sketches to production-ready drawings, ensuring robustness across the product lifecycle.

Collaborate with manufacturing and operations to translate designs into reliable production processes, implementing design for manufacturability and assembly principles.

Partner with the VP of Mechanical Engineering to build and grow a high-performance mechanical organization, including hiring, mentoring, and developing technical leaders.

Define and manage rigorous test and validation protocols to verify mechanical performance under cyclic loads, thermal gradients, and structural dynamics.

Work with cross-functional teams to ensure mechanical solutions meet grid-interactive performance requirements and regulatory standards for commercial power equipment.

Champion a culture of excellence without ego, using data-driven decisions and proactive collaboration to resolve complex engineering challenges.

Lead root cause analysis for mechanical failures, driving corrective and preventive actions that strengthen long-term product integrity.

Support the development of capital equipment and tooling strategies to enable production scale-up and cost optimization.

Ensure mechanical risk visibility across the portfolio, identifying dependencies and issues early to protect program timelines and delivery commitments.

Promote pragmatic optimism by leading projects that advance the company mission while maintaining disciplined engineering practices.

Requirements

You hold a Bachelor's degree in Mechanical Engineering or a related technical field, with a graduate degree strongly preferred.

You bring 15+ years of experience in mechanical product development, with a track record of delivering complex hardware in a high-growth environment.

You possess deep expertise in mechanical design, analysis, and testing for dynamic systems involving motion, pressure, and thermal management.

You have significant experience managing and scaling hardware portfolios, leading multiple concurrent engineering programs from concept to production.

You demonstrate strong leadership in managing teams of engineers, setting clear direction, and fostering a culture of technical rigor and ownership.

You are proficient with CAD, simulation, and product lifecycle management tools, using data to inform design decisions and trade studies.

You have a proven ability to translate customer and system requirements into robust mechanical architectures and specifications.

You are comfortable operating in an environment of ambiguity and rapid change, making high-impact decisions with incomplete information.

Nice to have

Experience in the energy, utilities, or industrial manufacturing sectors is preferred, particularly in roles involving power generation or electromechanical systems.

Background with electromagnetic machines, power electronics thermal management, or energy storage technologies is highly desirable.

Experience leading ISO quality management system implementations in a hardware development environment is a strong plus.

Prior work with fuel-flexible or alternative energy technologies is valued, aligning with our mission to enable sustainable power solutions.

Practical notes

This role is based in Menlo Park, California, and is eligible for salary-based compensation.

The position requires in-office presence during standard business hours.

Travel may be required for supplier visits, manufacturing audits, or customer engagements.

Candidates must be authorized to work in the United States without sponsorship for this position.