Principal Operations Engineer, Mechanical — Data Center Operations

About Fluidstack

We exist to make humanity more free. For most of human history, you farmed or you starved. Technology gave people more time for the things they wanted to do, instead of things they had to do. Powerful AI will be the biggest lever for human choice we've ever built – but only if models are aligned with what humanity actually wants.

There are groups building AI who don't share these goals. Whoever deploys frontier compute infrastructure fastest will decide whether AI expands human freedom or shrinks it.

We are singularly focused on delivering 10 to 100s of GWs of compute faster than anyone else, rethinking every layer of the stack. We acquire power, design and build data centers, and operate them – with teams spanning hardware and software. Speed and scale are our key differentiators. Come be part of building civilization‑scale infrastructure for AI.

We are seeking a Principal Operations Engineer, Mechanical to serve as the most senior technical authority for the operational mechanical and cooling infrastructure across our hyperscale AI data center portfolio. AI workloads create thermal conditions that punish anything less than precision execution — this role exists to make sure the systems that keep our compute cold are operated, maintained, and continuously improved at the standard the workload demands.

You will operate as the technical arm of senior operations leadership in the field – leading site assessments and operational audits, driving team technical readiness ahead of site activation, reviewing designs and specifications from an operational lens, and feeding operational learnings back into the design and manufacturing organization as we shift toward a productized, repeatable build model. You will be the senior voice in the room on chillers, cooling towers, CDUs, and the liquid‑cooling architectures that AI infrastructure increasingly depends on.

The ideal candidate has spent a career working on critical mechanical systems – in data centers, central plants, industrial cooling, or pharmaceutical or semiconductor environments – and is equally comfortable on a chiller skid, inside a P&w, and in front of a vendor pushing back on a flawed approach. Formal engineering credentials are valued but not required – practical depth, judgment under pressure, the ability to teach, and the discipline to keep critical infrastructure running through change are what define this role.

• Serve as the principal operational technical authority for mechanical infrastructure across the fleet, including chillers, cooling towers, CRACs/CRAHs, CDUs (direct‑to‑chip and immersion), dry coolers, economizers, pumping systems, water treatment, and associated piping infrastructure.
• Lead technical and operational site audits across active and pre‑activation sites; produce operational health assessments with prioritized findings and own the remediation roadmap through closure with site leadership.
• Own mechanical operational readiness for new sites coming online – assess team capability, validate procedures, and personally sign off on operational handover from commissioning to steady‑state operations.
• Review operational designs for new builds and capacity upgrades; represent the operational point of view in design forums and ensure operability, maintainability, and reliability concerns are surfaced and addressed before they are built in.
• Feed structured operational learnings back into the design and manufacturing organization as we shift toward repeatable, productized data center builds; reinforce patterns that work and drive out patterns that have not held up in operations.
• Author and approve high‑risk MOPs, EOPs, and AOPs; serve as the final technical approver for high‑consequence mechanical work across the fleet.
• Lead root‑cause analysis for significant thermal or mechanical events; drive corrective actions through to closure and ensure learnings propagate across all sites.
• Contribute to and uphold the mechanical safety program in partnership with EHS, with explicit accountability for refrigerant handling, confined space, LOTO, and high‑pressure systems discipline.
• Partner with QA/QC…