---
title: "Mechanical Engineer"
company: "Mariana Minerals"
company_url: "https://www.remjobs.works/companies/mariana-minerals"
url: "https://www.remjobs.works/job/mariana-minerals-mechanical-engineer-7790d3e8-923a-4ec3-b9dd-d18b2969725c"
apply_url: "https://jobs.ashbyhq.com/marianaminerals/3fa2126a-adfb-444c-a3ad-76d0305074da"
workplace: onsite
location: "San Francisco HQ"
employment_type: full-time
seniority: mid
role: software-engineering
region: united-states
salary: "$100,000–$150,000 per year"
date_posted: 2026-09-02T20:49:46.009Z
first_seen_by_remjobs: 2026-09-05T08:28:22.654Z
---

# Mechanical Engineer

**Mariana Minerals** · San Francisco HQ

Salary: $100,000–$150,000 per year

Apply: https://jobs.ashbyhq.com/marianaminerals/3fa2126a-adfb-444c-a3ad-76d0305074da

## About Mariana Minerals

Mariana Minerals is a software-first, vertically integrated minerals company focused on supplying the minerals critical to modern energy, AI, and defense technologies.

## About the role

### About Mariana Minerals

Mariana Minerals is a software-first, vertically integrated minerals company on a mission to supply the critical minerals powering modern energy, AI, and defense technologies. We’re reimagining the minerals supply chain by combining deep industry expertise with advanced software, automation, and data-driven decision-making.

#### The Role

Mariana Minerals is looking for a highly motivated Mechanical Engineer to join our San Francisco Pilot Plant team. You will support the design, installation, and maintenance of first-of-its-kind refining processes for critical minerals. This position plays a critical role in bridging R&D and Operations, ensuring our equipment and work processes are robust, safe, cost-effective, and suitable for commercial production.

#####

#### What You'll Do

- Drive design, fabrication, installation, modification, startup, and commissioning of new equipment and pilot plant systems.

- Troubleshoot mechanical issues and implement practical solutions to maintain safe, reliable, and efficient plant operations.

- Work closely with process engineers and R&D scientists to translate process requirements into equipment modifications, mechanical designs, and plant improvements.

- Create and maintain engineering documentation, including P&IDs, process and control narratives, equipment specifications, drawings, CAD models, and equipment manuals.

- Identify opportunities to improve equipment reliability, maintainability, and operational performance

- Support the development of software and to help drive rapid equipment design, plant reliability, and safe operation

- Travel to Mariana sites to support new projects, start-up/commissioning, and troubleshooting initiatives

#### What You'll Bring

- B.S., M.S., or PhD in Mechanical Engineering or a related field

- Experience in automated manufacturing, operations, process scale-up, or plant design in minerals processing, chemicals, specialty materials, oil & gas, or related industries

- Demonstrated experience driving equipment design, commissioning, operations, and reliability

- Ability to wear multiple hats and take on additional scope in areas such as process engineering, operations, maintenance, and project execution

- Strong troubleshooting and problem-solving skills in hands-on plant environments

- Strong commitment to Health, Safety, and Environmental compliance and mechanical integrity standards

- Excellent technical writing, communication, and teamwork skills

- Comfortable working in fast-paced environments and managing ambiguity

#### Our culture is built on four principles:

**Everyone Gets Home Safe. **We never put speed or cost ahead of people.

**Extreme Ownership. **We take full responsibility for outcomes, relentlessly driving toward solutions.

**Engineer Out Requirements, then Automate. **We simplify, optimize, and then automate for scale.

**Share Your Legos.** We collaborate openly, share knowledge, and empower each other to build bigger, better solutions.

**Join us as we build the future of responsible mineral sourcing and supply!**

---

Source: Mariana Minerals's own career page, read by RemJobs. Canonical HTML version: https://www.remjobs.works/job/mariana-minerals-mechanical-engineer-7790d3e8-923a-4ec3-b9dd-d18b2969725c