Atomic Machines Exits Stealth with $250M and a Relay That Opens 1,000× Faster Than Anything on the Market

On October 7, 2026, a company called Atomic Machines exited six years of stealth with $250 million in cumulative funding and one very specific product: a relay for AI data centers that opens 1,000 times faster than anything currently on the market. The company's backers include OneIM, Gigafund, XTX Ventures, Valor Equity Partners, and the Regents of the University of California.

The founder is Jeff Holden — Amazon's tenth employee, one of the people who built Amazon Prime, and later Uber's first chief product officer. He has spent six years building what he calls a Matter Compiler: a manufacturing system that produces three-dimensional micro-machines directly from a digital design file, with no molds or fixed tooling.

The Problem It Solves

AI data centers are in the middle of a power transition. GPU clusters demand so much current that facilities are moving from 48-volt to 800-volt DC power distribution. At 800 volts, the energy that can be released in a fault is enormous, and it releases in microseconds. Conventional mechanical contactors — the relays that disconnect circuits in a fault — take several milliseconds to open. At 800 volts, that's too slow. The energy is already doing damage before the switch opens.

Atomic Machines' first product, the PrimeSwitch PS-150, opens in roughly 50 microseconds, which the company says is about 1,000 times faster than a conventional contactor. It handles 150 amps of continuous current in a package measuring 9.5mm by 3mm. Early-access customers are already receiving units for evaluation.

What Makes the Matter Compiler Different

The PrimeSwitch is built using Atomic Machines' proprietary manufacturing process, and that process is arguably the bigger story. Traditional MEMS (micro-electromechanical systems) fabrication uses the same photolithographic masks that semiconductor fabs use — expensive, slow to modify, and limited to essentially two-dimensional geometries. 3D printing is flexible but limited to coarser tolerances and typically a single material.

Atomic Machines' Matter Compiler sits between those two worlds. It can produce features down to single-digit microns and combine multiple materials in a single build cycle, without custom masks. The company claims this lets them iterate on hardware designs the way software teams iterate on code: push a new design file, get a new physical device.

The Bigger Picture

The $250 million figure is cumulative, not a newly announced round, and Atomic Machines has been unusually quiet for a well-funded hardware startup. The stealth period makes sense given the nature of the technology: physical fabrication processes are hard to patent-fence, and showing too much too early invites well-capitalized competitors to start copying the approach.

Whether the Matter Compiler generalizes beyond the PrimeSwitch to the robotics and medical device applications the company mentions is the open question. But the timing is good: the AI hardware buildout is creating demand for power components that don't yet exist at the required speed and density, and Atomic Machines has a product on the market — today — that addresses the most immediate bottleneck.