Senior Cryogenic Systems Engineer

Category

Engineering

Work Type

On-site

Employment

Full-time

Location

Bay Area

Salary Range

$140,000 - $175,000

per year

Posted on November 20, 2025

About This Role

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
As a Cryogenic Process & Systems Engineer at Until, you’ll lead design and execution of high-pressure cryogenic fluid systems that support our perfusion and rewarming hardware. You’ll translate process requirements into engineered systems—pumps, piping, heat-exchangers, instrumentation, and safety infrastructure—to enable organ-scale vitrification and rewarming.

You’ll work side-by-side with mechanical engineers, materials scientists, and biologists to build, test, and iterate hardware that pushes the boundaries of cryogenic processing.

What You’ll Do

  • Design, build, and validate cryogenic fluid systems including high-pressure piping, pumps/compressors, valves, manifolds, instrumentation, and insulation.
  • Create and maintain process documentation (PFDs, P&IDs), system architecture drawings, and simulation/analysis of thermal/fluid/structural performance.
  • Size and select cryogenic and high-pressure equipment, coordinate integration, commissioning, and test of prototypes.
  • Perform analyses of pressure drop, NPSH, fluid/thermal behavior, material embrittlement, heat in-leak, and boil-off dynamics.
  • Lead safety architecture for cryogenic systems: relief/vent systems, purging strategies, instrumentation, code compliance (ASME/API/NFPA/CGA).
  • Develop and run hardware test rigs, collect data, investigate failures, iterate rapidly.
  • Collaborate with cross-functional teams (mechanical, thermal, materials, biology) to integrate cryogenic hardware into larger systems.
  • About You

  • Bachelor’s degree in Mechanical, Chemical, Petroleum or related Engineering discipline.
  • At least 3 years of experience working in one or more of these areas: LNG/liquid-gas processing, cryogenic fluids (LN₂/LNG/LOX/LH₂), or high-pressure industrial gas systems.
  • Hands-on experience with high-pressure piping, rotating equipment (pumps/compressors), valves and instrumentation in cryogenic or industrial-gas contexts.
  • Strong foundation in fluid mechanics, thermodynamics, heat-transfer, material behavior at low temperature / high pressure.
  • Comfortable working in a hardware lab environment with prototype development and test.
  • Bonus points if you have experience with flow-through or perfusive cooling architectures, process simulation tools (Aspen HYSYS/ProMax), HAZOPs or safety reviews, commissioning or vendor/EPC coordination, or prior work in LNG, industrial gases, aerospace cryogenics, or advanced cooling systems.
  • Benefits

  • A mission-driven environment tackling one of the hardest problems in medicine.
  • The opportunity to build and direct a world-class imaging program from the ground up.
  • A deeply interdisciplinary team of scientists, engineers, and builders.
  • Generous medical, dental and vision insurance coverage
  • 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
  • Ready to Apply?

    Join our team and be part of the future of medicine and technology.

    Apply for Senior Cryogenic Systems Engineer