Mechanical Systems Engineer

Marietta, GAFull-time (Onsite)

The Mission

At 4Earth, we are building advanced resource recovery technology that plugs seamlessly into factories and mission-critical infrastructure to turn waste into value. To do this, we cannot rely on off-the-shelf components or standard industrial dogmas.

We need to engineer the mechanical and structural components of machines that must survive, contain, and process fluids in the harshest industrial environments. We are looking for a Mechanical Systems Engineer who views every seal, weld, and structural member as their personal responsibility. You will be responsible for the "body and grit" of our technology—from the heavy-duty frames that support our reactors to the precision fluid dynamics that give them life. We want an inventor who gets their hands dirty, wrenches their own fittings, and iterates until the physics works.

The Role

You will own the mechanical architecture of our product A–Z. This is a role at the intersection of Mechanical Engineering, Structural Design, and Design for Manufacturing (DFM). You will not be handing off CAD models to a shop. You will be:

Designing complete mechanical systems from blank-sheet to commission.
Building units with your own hands.
Scaling designs for mass production and part selection.

What You Will Build

The Physical Chassis

Design and integrate structural frames and enclosures that protect our technology and withstand extreme industrial conditions.

The Fluid Core

Manage the process distribution architecture, handling high-pressure piping, pumps, and reactors that drive our chemical and mechanical recovery.

The Physical Product (DFM)

You will optimize assembly layouts, material selection, and modularity to ensure our systems can be manufactured at velocity.

The Supply Chain

You don’t just pick parts; you spec and validate custom fabrications and industrial components that are available, reliable, and cost-effective. You own sections of the BOM.

The DNA We Are Looking For

Experimentalist First

You don’t just simulate; you prototype, weld, and test. You have a portfolio of physical machines you have built, not just renders you have drawn.

First-Principles Thinker

You understand the fundamental physics of why a seal leaks or a beam buckles. You don’t guess; you hypothesize and verify with a torque wrench and pressure gauge.

Extreme Ownership

If a fitting fails, you don’t blame the supplier. You own the failure, find the root cause, and engineer it out of existence.

Cross-Disciplinary

You’ll speak “Stress/Strain” to the structural team, “Flow Rate” to the process engineers, and “Cycle Time” to the manufacturing floor.

Critical Requirements

Hands-On Ownership

2+ years of experience taking mechanical systems from concept (P&ID/CAD) to physical commissioning.

System Architecture

Demonstrated mastery of machine design, fluid handling systems, and structural integrity.

Thermal & Fluid Proficiency

Ability to safely design and troubleshoot pressurized systems and heat-intensive processes.

Component Selection

Deep experience spec’ing valves, pumps, and specialized industrial hardware.

DFM Mindset

Experience designing for assembly; you understand how to layout a machine so a human can actually build and service it.

Nice to Haves

Fabrication Skills: Ability to weld (TIG/MIG) or operate manual/CNC machining equipment.
Experience in water treatment, chemical processing, or similar process-heavy industries.
Experience scaling a hardware product from a garage prototype to pilot production.

Why 4Earth?

We are doing the hard thing—re-engineering the water cycle to secure the future. If you want a comfortable 9-to-5 where you push paper, this isn’t for you. If you want to build the technology that ensures our planet remains habitable, join us.