Sr Mechanical Engineer

Hirewell; San Francisco (CA); On-site; USD 150,000 - 210,000; Full time

Job summary

Hirewell is seeking a Senior Mechanical Engineer to lead the design of exo-organ devices, interfacing with biologists to advance regenerative medicine. This role focuses on mechanical design, biocompatible housings, and fluidic systems for biohybrid devices that aim to augment human organ function.

You will prototype and optimize microfabrication and assembly workflows, model fluid dynamics, and work in cross-functional teams to deliver functional devices and validated testing platforms.

Qualifications

• BS or higher in Mechanical Engineering; MS/PhD preferred.
• 5+ years in mechanical design, ideally for medical systems.
• Proven track record designing/assembling fluidic devices interfacing with tissues/fluids.
• Deep understanding of fluid dynamics and transport phenomena in complex systems.

Responsibilities

• Lead mechanical design lifecycle from concept to prototypes for exo-organ devices.
• Design and iterate biocompatible housings and fluidic systems with biological components.
• Develop microfabrication and assembly workflows for device components.
• Model fluid flow, diffusion, and stresses to inform design decisions.
• Engineer perfusion and fluid-delivery strategies for dense tissues.
• Integrate bioreactor modules with sensors, pumps, and controls for real-time monitoring.
• Build life-sized and miniaturized multiplexed prototypes for testing.

Skills

Biomechanical design

Fluid dynamics

CAD software

Prototyping

Medical device design

Education

Bachelor's in Mechanical Engineering

MS/PhD preferred

Tools

SolidWorks

Fusion 360

COMSOL

Job description

Job Title: Senior Mechanical Engineer, Exo-organ Devices
Overview:
Join a bold and interdisciplinary team at the frontier of tissue engineering. We’re developing biohybrid systems to replace or augment human organ function, that are encapsulated, and which do not require invasive transplantation: exo-organs. We’re seeking a Senior Mechanical Engineer to lead the design for the mechanical part of our exo-organ devices, and collaborate with our biologists to build a biohybrid device that will revolutionize healthcare.
This role is ideal for a creative engineer excited by the idea of building biological devices that enable the next frontier of regenerative medicines.
What You’ll Do:

• Lead the mechanical design lifecycle of our exo-organ devices — from concept development to functional prototypes
• Design, prototype, and iterate biocompatible housing and fluidic systems that integrate seamlessly with biological components
• Develop and optimize precision microfabrication and assembly workflows for device components
• Model and simulate fluid flow, diffusion, and mechanical stresses across device architectures to inform design decisions
• Engineer perfusion and fluid-delivery strategies to support dense, non-vascularized tissues
• Integrate and customize bioreactor modules with sensors, pumps, and control systems for real-time monitoring and environmental modulation
• Build both life-sized functional prototypes and miniaturized multiplexed systems to accelerate biological testing and validation

Qualifications:

• B.S. or higher in Mechanical Engineering (M.S. or Ph.D. preferred)
• 5+ years of experience in mechanical design, ideally for medical systems
• Proven track record designing and assembling fluidic devices that interface with biological tissues and/or fluids
• Deep understanding of fluid dynamics, flow control, and transport phenomena in complex systems
• Proficiency with CAD software (e.g., SolidWorks, Fusion 360, or COMSOL) and rapid prototyping tools
• Experience with fabrication techniques such as CNC machining, soft lithography, laser micromachining, or 3D printing

Preferred Experience:

• Familiarity working in cross-functional teams with biologists or clinicians
• Exposure to system integration of sensors, actuators, and control electronics
• Understanding of materials compatibility in biological systems
• Experience in robotics

Who You Are:

• A hands-on tinkerer–you enjoy designing, fabricating and maintaining devices.
• Comfortable operating in an early-stage environment where iteration and adaptability are critical.
• Collaborative, communicative, and eager to learn about new scientific fields.
• Eager to contribute to a company redefining the field of organ transplantation.

Why Join Us:
We are a small, and mighty team of scientists and engineers working at the frontier of regenerative medicine for human enhancement purposes. Daily work looks like fun and rigorous research paired with creative problem-solving and intellectual curiosity where action matters and diversity of thought is respected, and essential to how we solve problems. A space for tinkerers, explorers and developers who desire an intellectual home where controls, excellent experimental design, and mastery over the literature are championed principles. We are on a quest to extend human life, and we sincerely hope you can join us on our mission.