Principal Engineer, Advanced Cooling Engineering

Flex is the diversified manufacturing partner of choice that helps market-leading brands design, build and deliver innovative products that improve the world. A career at Flex offers the opportunity to make a difference and invest in your growth in a respectful, inclusive, and collaborative environment. If you are excited about a role but don't meet every bullet point, we encourage you to apply and join us to create the extraordinary.

Flex intends to spin off its Cloud and Power Infrastructure segment into a new, independent publicly traded company, which we’re calling Spin Co, until the name is unveiled. The spin is planned for Q1 2027. If the intended spin occurs, this role will support Spin Co, which will focus on critical digital infrastructure, delivering end-to-end power and thermal management solutions for AI data centers and other mission-critical applications.

To support our extraordinary teams who build great products and contribute to our growth, we’re looking to add a Principal Engineer, Advanced Cooling Engineering located in Austin, TX. Reporting to the Chief Technology Officer, the Principal Engineer, Advanced Cooling Engineering will lead Spin Co’s advanced thermal management strategy for next-generation AI data center infrastructure. This role is responsible for developing the roadmap and engineering capability across direct-to-chip liquid cooling, secondary fluid networks, CDUs, rear-door heat exchangers, hot-aisle containment, facility-level cooling, and integrated thermal management.

The role will build on our established direct-to-chip liquid cooling capability and expand from rack-level thermal solutions through facility-scale cooling systems.

This is a hands-on technical leadership role. You will be in the details, generating architectures, models, specifications, and analysis yourself rather than only directing others to do so. We are looking for a leader who can run a full design-build cycle, set the technical bar by example, and is measured more by working hardware and validated designs than by decks and white papers.

• Define and lead the multi-generation cooling roadmap across rack, row, hall, and facility-level thermal management.
• Lead applied R&D and prototype development for high-heat-flux cooling solutions supporting next-generation AI XPUs and high-density compute platforms.
• Develop Spin Co’s integrated thermal management strategy, connecting rack-level liquid cooling, CDUs, facility cooling, containment, and controls into a coordinated platform.
• Partner with Systems Architecture Engineering to ensure thermal systems are designed concurrently with power, IT infrastructure, controls, and modular product architectures.
• Establish design standards, interface control documents, product specifications, and validation requirements for scalable liquid cooling platforms.
• Support customer-facing technical reviews with hyperscalers, colocation providers, neoclouds, and ecosystem partners.
• Drive manufacturability, reliability, cost optimization, and design-for-scale practices in partnership with operations, supply chain, quality, and manufacturing engineering.

• Bachelor’s degree in Mechanical Engineering, Thermal Engineering, Aerospace Engineering, or related technical field;
  Master’s or PhD preferred.
• 12+ years of experience in thermal systems, liquid cooling, HVAC, data center infrastructure, or advanced mechanical systems.
• Demonstrated leadership in electrical, mechanical, and/or systems architecture engineering disciplines
• Demonstrated expertise in fluid dynamics, heat transfer, pumps, manifolds, valves, material compatibility, mechanical reliability, and thermal/fluid simulation.
• Experience with…