# Machinist / Prototype Fabrication Engineer

> Becoming · San Francisco, United States · Full-time · Posted 2026-10-22

**Salary:** USD 90,000–140,000

**Workplace:** on_site

## Description

## About Becoming

Becoming is building a new technology platform at the intersection of developmental biology, engineering, and AI.

Our work requires highly customized hardware. We are looking for an exceptional **Machinist / Prototype Fabrication Engineer** to help us build it.

## The Role

You will work directly with Becoming's engineers and scientists to rapidly turn designs into physical hardware.

This is primarily an R&D and prototyping environment rather than conventional production manufacturing. You should enjoy rapid iteration, unusual engineering challenges, and working closely with the people designing and testing what you make.

## What You'll Do

-   Machine precision components for experimental hardware.
-   Operate CNC mills, lathes, and manual machining equipment.
-   Build custom fixtures, jigs, adapters, enclosures, and experimental components.
-   Work from CAD, engineering drawings, sketches, and early-stage concepts.
-   Advise engineers on manufacturability, tolerances, materials, and fabrication approaches.
-   Rapidly modify components in response to experimental results.
-   Develop machining strategies for unusual geometries and low-volume parts.
-   Inspect components and verify critical dimensions.
-   Support assembly, troubleshooting, repair, and modification of experimental hardware.
-   Help build a world-class internal rapid-prototyping capability.

## Requirements

## Must Have

-   Have substantial hands-on machining experience.
-   Are highly capable with CNC milling and/or turning.
-   Are comfortable with manual mills and lathes.
-   Can independently take a component from drawing or CAD through fabrication.
-   Understand GD&T, tolerancing, fits, surface finishes, and inspection.
-   Have strong intuition for manufacturability.
-   Are comfortable working across metals and engineering polymers.
-   Enjoy working directly with engineers in a fast-moving R&D environment.
-   Take exceptional pride in the quality of physical things you build.

## Nice to Have

-   CAM programming
-   Multi-axis machining
-   Precision fabrication
-   Scientific instrumentation
-   Medical-device hardware
-   Prototype development
-   Metrology and inspection
-   Welding or other fabrication techniques
-   Experience working in an internal R&D machine shop

## What Success Looks Like

Ideas move from CAD to experiment dramatically faster because difficult hardware can be fabricated, tested, modified, and rebuilt under one roof.

## Benefits

-   Competitive salary and meaningful equity depending on experience level
-   Full benefits
-   High-trust, high-ownership environment
-   Rapid growth in scope and responsibility

## Apply

[Apply at Becoming](https://apply.workable.com/becoming/j/326B427703/apply)

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