Senior Mechanical Engineer

Capybara Energy; Woburn (MA); On-site; USD 90,000 - 120,000; Full time

Benefits offered by this job

Equity

Company funded HSA

3 weeks paid time off

Sick pay & parental leave

10 paid holidays

Health and dental insurance

401(k) match

Advanced snacks

Job summary

Capybara Energy in Massachusetts seeks a Senior Mechanical Engineer to design and develop grid-scale energy storage hardware and ancillary systems. This hands-on role focuses on bringing innovative concepts from design to manufacturing, requiring direct experience with physical products.

You will collaborate across disciplines, perform FEA, select materials, and contribute to IP protection, with responsibilities spanning prototyping, testing, and production readiness.

Qualifications

• Bachelor’s or Master’s degree in Mechanical Engineering or related field.

Responsibilities

• Design, develop, and refine mechanical components and assemblies for our energy storage hardware.

Skills

CAD software

Structural analysis

DFM

Manufacturing principles

Materials knowledge

Teamwork & communication

Troubleshooting

Education

Bachelor’s or Master’s degree in Mechanical Engineering

Tools

FEM/FEA software

Job description

Mechanical Engineer wanted for a groundbreaking journey to develop grid-scale energy storage technology. Average pay. Demanding hands‑on work, intense challenges, relentless problem‑solving. Failure possible. Honor and recognition if successful.

Pay: $90,000.00 - $120,000.00 per year

Senior Mechanical Engineer - Product and system design

About the Role:

We’re looking for a rockstar Engineer to design and develop an energy storage technology and ancillary systems.

* Please note that this position requires previous experience in direct involvement in the design and commercialization of a physical product.

This is a hands‑on role, ideal for an engineer who enjoys product design, prototyping, and problem‑solving. You’ll work closely with our team to bring innovative, real‑world products from design to manufacturing.

Key Responsibilities:

• Design, develop, and refine mechanical components and assemblies for our energy storage hardware.
• Collaborate with engineers and scientists to document and improve designs.
• Support the full product lifecycle; from concept and prototyping to validation, testing, and production.
• Troubleshoot design and performance challenges with creativity and technical precision.
• Oversee fabrication, testing, and performance evaluation.
• Conduct FEA simulations, tolerance analyses, and material selection for optimized designs.
• Bring creative, practical solutions to complex engineering challenges and help protect key IP.
• Participate in design, brainstorming, and problem‑solving with the broader engineering team.
• Contribute to internal design standards, tools, and documentation processes.

Qualifications:

• Bachelor’s or Master’s degree in Mechanical Engineering or related field.
• 3+ years of experience in mechanical design and product development.
• Demonstrated experience designing and launching a physical product (UL listed or outdoor rated preferred).
• Strong understanding of manufacturing principles and process optimization.
• Proficiency in CAD software, structural analysis, and DFM.
• Solid understanding of materials, manufacturing processes, and design for manufacturability.
• Strong technical, creative, and troubleshooting skills.
• This role requires close collaboration across disciplines, so teamwork and communication are essential.

Preferred Skills:

• Knowledge of electronics integration or mechatronics.
• Experience working in regulated or safety‑critical environments.
• DFMA
• Experience coordinating with contract manufacturers or large‑scale production partners.

What We Offer:

• Equity
• Company funded HSA
• 3 weeks paid time off
• Sick pay & parental leave
• 10 paid holidays
• Health and dental insurance
• 401(k) match
• Advanced snacks

* U.S. citizenship or lawful permanent resident status is required due to federal contract requirements.