TRECQ

Staff Mechanical Engineer

EngineeringStaffonsiteMenlo Park, CA
SalaryPosted Aug 5, 2026

About this role

About Mainspring

Mainspring Energy manufactures and delivers fuel-flexible, low-emissions local power solutions that rapidly add new capacity and deliver reliable, affordable, and sustainable electric power. The company began commercial shipments of its Mainspring Linear Generators in 2020 and today has hundreds of megawatts in advanced development and field operations for leading Fortune 500 companies, data centers, and utilities. Mainspring also partners with global energy leaders including AEP, NextEra Energy Resources, Schneider Electric, and more.

The core values that ground our work, guide our decisions, and connect us together:

  • Pragmatic Optimism
  • Excellence without Ego
  • Proactive Collaboration

About the Role

Mainspring is seeking a Mechanical Engineer to own defined-scope mechanical engineering tasks, workstreams, or moderate-complexity projects for our Linear Generator platform. In this role, you will design mechanical hardware, support analysis and testing, drive assigned work through validation and release, and work cross-functionally with engineering, manufacturing, quality, supply chain, test, and service teams.

This role is intended for engineers who have developed practical mechanical engineering experience through multiple design, analysis, test, release, or implementation cycles. A strong candidate should be able to independently own defined-scope engineering work, apply sound mechanical fundamentals, identify common risks, communicate clearly, and follow through on deliverables with support available for ambiguity, complex tradeoffs, or higher-risk decisions.

Candidates who are still primarily learning engineering fundamentals, company processes, and task-level execution may be better aligned to an Associate Mechanical Engineer role, while candidates who have already demonstrated independent ownership of significant projects, subsystems, or technical workstreams may be better aligned to a Senior Mechanical Engineer role.

About Mainspringenergy

Interested?

Find the right person, then reach out. Trying more than one channel only helps your odds.

1
Find who to reach
Pick the person worth a direct note. Reveal a real email (one credit) or find a likely one.
New accounts start with 3 free reveals.
2
Reach out
Pick someone above, then draft an email or a LinkedIn note to them.
3
Or apply on their site
The front-door route, plus TRECQ drafts your application answers to paste.
Apply on Mainspringenergy ↗
TRECQ writes your "why this company / why you" to paste into the form.