Sr. Mechanical Engineer, Fluidics/Perfusion

Job Description

Job Description

Until is a moonshot company building a “pause button” for biology. Our near-term focus is organ-scale reversible cryopreservation: preserving donated organs at subzero temperatures without ice formation, then rewarming them uniformly for transplant. By solving this grand challenge, we’re laying the foundation for whole-body reversible cryopreservation, giving patients a bridge to future cures.

To achieve our goal, we are assembling an interdisciplinary team to develop perfusion systems, cryoprotectant formulations, and vitrification and rewarming hardware.

We envision a future where no transplantable organ is lost to logistics, and no terminal diagnosis is final because patients can safely wait for future medicine to arrive.

About the Role

Accomplishing our mission requires skilled engineers pushing the boundary developing new systems for heat and mass transfer in N-of-1 perfusion and heat exchange devices. We're building a fast-paced, scrappy team of engineers to create technology indistinguishable from magic.

• Track record of exceptional engineering abilities
• Experience leading highly technical, multidisciplinary teams
• 3+ years experience/graduate level in Mechanical Engineering, Physics, or equivalent
• Deep understanding of heat and mass transfer principles alongside fluidic design experience
• High degree of autonomy across full engineering stack: electromechanical design and fabrication, control software, physical modeling
• Desire to join a fast-paced, scrappy engineering team

• Experience with organ perfusion in a research or clinical context
• Experience working in a startup

• Opportunity for outsized impact creating the future as an early team member
• Generous medical, dental and vision insurance coverage for employees and their dependents
• Flexible time off and paid holidays
• Competitive compensation package, including salary and equity
• Access to a 401(k) retirement savings plan
• FSA and commuter benefits
• Subsidized lunch daily

While this represents our expected range based on market data, final compensation will be determined based on your specific qualifications and may be outside this range. Please keep in mind that the equity portion of the offer is not included in this estimate.

As an equal opportunity employer, Until is committed to providing employment opportunities to all individuals. All applicants for positions at Until will be treated without regard to race, color, ethnicity, religion, sex, gender, gender identity and expression, sexual orientation, national origin, disability, age, marital status, veteran status, pregnancy, or any other basis prohibited by applicable law.

We may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses and identifying potential inconsistencies or verification signals in application materials based on available information. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us.