Simulation software startup Antioch Inc. today announced $32 million in new funding for product development, engineering hires and deeper simulation capabilities aimed at its customers — robotics, autonomy and perception teams.

Antioch is going after the way autonomous machines get tested today. Every change to a robot, a drone or an industrial machine still has to be proven on physical equipment, at a cost in hardware and engineer hours. Its software calibrates a simulation to a customer’s own hardware, then runs it on cloud infrastructure.

A team that could afford one physical experiment now can run thousands of simulated evaluations in parallel. Co-founder Harry Mellsop said taking autonomous systems into the real world requires a new approach to testing, one built on high-fidelity simulation that supports “faster, safer, and more reliable deployment.”

“Antioch is changing how we develop and validate complex systems by enabling us to rely on simulation with a level of confidence that wasn’t previously possible,” said Jason Mitura, vice president of software development at Amazon.com Inc. and chief product officer at its Ring unit. “Antioch’s simulations have closely matched our physical test results, including in scenarios we deliberately held out of calibration.”

The startup is about 16 months old. Mellsop worked on Autopilot software at Tesla Inc. and started Antioch in May 2025 with four others, two of whom, Alex Langshur and Michael Calvey, had previously founded Transpose Inc. Chainalysis Inc. bought that security and intelligence startup in 2023. Google DeepMind and Meta Platforms Inc.’s Reality Labs supplied the remaining two co-founders.

Nvidia Corp. is a partner. Antioch is integrating the chipmaker’s open physical artificial intelligence stack, including Omniverse libraries and the Isaac Sim and Isaac Lab robotics frameworks, to help developers spread testing across thousands of simulated scenarios. Nebius Group N.V. is a partner too, supplying cloud infrastructure. Evan Helda, head of physical AI at Nebius, called simulation “one of the hardest parts of the stack to get right.”

Greylock Partners led the Series A round, with A* Capital, Category Ventures, BoxGroup Ventures and Icehouse Ventures Ltd. joining. Individual backers include Palantir Technologies Inc. Chief Technology Officer Shyam Sankar, Foxglove Inc. Chief Executive Adrian Macneil and Ian Andrews, an Nvidia executive who previously worked at Groq Inc.

Saam Motamedi, a general partner at Greylock, said physical AI and robotics are “hitting a key inflection moment” and that Antioch is building the core development platform for the next phase of the market.

A $4.25 million pre-seed round in December was followed by $8.5 million in April. Backers have now put $44.75 million into the company.

Image: Antioch