Thermal Engineer - SoC to Rack Integration

Majestic Labs • Los Altos, CA

19h • Onsite

About The Position

Majestic Labs is a fast-moving, US-Israeli AI startup building next-generation infrastructure for the world’s most demanding AI workloads. Our mission is to accelerate the future of intelligence and make it ubiquitously accessible by delivering full stack custom AI servers optimized for large-scale inference and training. We are seeking a Senior Thermal Engineer with 10+ years of experience to own the full thermal design lifecycle of advanced cooling systems for high-performance computing hardware. This is an on-site, individual contributor role for a candidate with deep hands-on expertise in liquid cooling architecture from silicon-level cold plate design through rack-scale fluid infrastructure, CFD simulation, and AI/GPU-based system design.

Requirements

• 10+ years of thermal engineering experience with deep expertise in liquid cooling systems spanning SoC-level and rack-level implementations in high-performance or data center environments.
• B.S. or M.S. in Mechanical Engineering or a related field.
• Proven track record of owning at least one full product lifecycle — from concept through high-volume manufacturing (HVM).
• Liquid Cooling Expertise: Expert-level experience in cold plate design for high-power silicon devices and rack-level liquid-cooled manifold systems, including micro-channel optimization, blind-mate quick disconnect integration, and full loop architecture from node to rack scale.
• Fluid Systems & Simulation: Deep understanding of water pressure dynamics, flow balancing, and leak-mitigation best practices, with proficiency in CFD tools (e.g., Ansys Fluent, Icepak, or equivalent) to simulate and validate complex thermal and fluid systems from component to system level.
• Familiarity with airflow principles and air cooling requirements for high-density server and rack architectures.
• Direct experience with AI/GPU-based compute architectures and ultra-high-density power delivery systems.

Nice To Haves

• Direct experience with thermal interface materials (TIMs), including selection, characterization, and application in high-power assemblies.
• Deep familiarity with Open Compute Project (OCP) or ORV3 standards.
• Experience with blind-mate liquid and power interfaces.

Responsibilities

• Own end-to-end thermal design from concept through production, spanning SoC-level cold plate development through rack-scale liquid cooling infrastructure, including hybrid air and liquid cooling systems.
• Design and optimize high-power silicon cold plates, including internal micro-channel geometry, thermal interface integration, and fluid inlet/outlet configuration directly at the SoC package level.
• Architect and validate rack-level liquid cooling infrastructure including manifold layout, blind-mate quick disconnect integration, and full loop pressure and flow management.
• Drive CFD simulation efforts to validate cooling strategies for high-density nodes, optimizing fluid flow, pressure drop, and heat transfer from chip to rack.
• Partner closely with internal hardware teams and external partners to deliver integrated thermal solutions for AI/GPU-based platforms.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior
• Education Level: Associate degree