Antioch

Antioch Agent is a browser-based simulation environment for robotics and physical AI teams, letting developers onboard a robot, build high-fidelity scenes, and run closed-loop tests against the full autonomy stack without leaving the tab. The pitch is straightforward for any team working on autonomy: compress field testing cycles that normally take weeks into hours by spinning up digital instances of hardware wired to simulated sensors, then iterate on policies, edge cases, and training data inside the same loop. Antioch lets robotics developers spin up digital instances of their hardware connected to simulated sensors, enabling reinforcement learning, edge case testing, and training data generation without building physical test environments. CEO Harry Mellsop says it's 'the first time you can have autonomous agents iterate on a physical autonomy system, and actually close the feedback loop.' The launch matters now because robotics development remains gated by hardware, and most teams either build mock warehouses or buy expensive data collection runs to train policies. Antioch is targeting the sim-to-real gap, the difficulty in ensuring that robots trained in virtual environments can perform reliably in the physical world, with an agentic workflow that lets autonomous systems iterate on themselves inside the simulator. Use cases already in the wild span autonomous vehicles, agricultural drones, and academic research, including an experiment where MIT CSAIL researcher David Mayo directs AI models to design robots, then uses Antioch's simulator to validate their real-world viability . The company is based in New York and led by CEO Harry Mellsop, previously of security startup Transpose, with cofounders and early team drawn from Google DeepMind and Meta Reality Labs . Antioch recently raised an $8.5 million seed round at a $60 million valuation, led by A* and Category Ventures, with participation from MaC Venture Capital, Abstract, Box Group, and Icehouse Ventures. Antioch Agent is the first public product built on that thesis, aimed at founders and operators who want to develop physical autonomy at something closer to the cadence of shipping software.