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. Job Summary Flex intends to spin off its Cloud and Power Infrastructure segment into a new, independent publicly traded company, which we’re calling SpinCo, until the name is unveiled. The spin is planned for Q1 2027. If the intended spin occurs, this role will support SpinCo, 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 SpinCo’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. What a typical day looks like: 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 SpinCo’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. The experience we’re looking to add to our team: 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 direct-to-chip liquid cooling, CDUs, rack/server thermal design, or high-density data center cooling strongly preferred. Proven ability to lead multidisciplinary engineering teams from concept through validation and commercialization. Strong cross-functional leadership across product management, PMO, operations, manufacturing, supply chain, quality, and customers. Demonstrated personal track record producing thermal designs, fluid and thermal simulation, and validated hardware, not only managing teams that do. #LI-EA1 EA42 SS26 AA01 CH12 MS14 CC11 EC37 PF38 JS21 NV60 FL75 What you'll receive for the great work you provide: Full range of medical, dental, and vision plans Life Insurance Short-term and Long-term Disability Matching 401(k) Contributions Vacation and Paid Sick Time Tuition Reimbursement Application Deadline: Applications for this job position will be accepted for at least five days following the job posting start date below and continuing until the end date below or until the position is filled. This posting may close sooner due to application volume. Job Posting Start Date 08-25-2026 Job Posting End Date 01-01-2027 Job Category Production Engineering Is Sponsorship Available? No Flex is an Equal Opportunity Employer and employment selection decisions are based on merit, qualifications, and abilities. We do not discriminate based on: age, race, religion, color, sex, national origin, marital status, sexual orientation, gender identity, veteran status, disability, pregnancy status, or any other status protected by law. We're happy to provide reasonable accommodations to those with a disability for assistance in the application process. Please email and we'll discuss your specific situation and next steps (NOTE: this email does not accept or consider resumes or applications. This is only for disability assistance. To be considered for a position at Flex, you must complete the application process first).