Flow Engineering, a company building an agentic platform for hardware development, has raised US$50 million in a Series B round at a US$750 million valuation. The San Francisco-based company announced the financing on September 30, 2026, and said the capital will help bring the speed of AI-driven software development to physical engineering. The financing brings together investors who have backed several defining hardware and AI companies over the past two decades.
Funding and Investor Backing
The Series B round was co-led by Antonio Gracias, founder of Valor Equity Partners, and Gavin Baker, Managing Partner at Atreides Management. Sequoia Capital, which led Flow's Series A, also participated alongside Human Capital, Evantic, SV Angel, Odyssey, and EQT. Individual investors included Hugging Face co-founder Thomas Wolf, Mercedes-Benz CIO Jonas von Malottki, and Formula 1 world champion Nico Rosberg, while Roelof Botha joined the board as an independent director and personally invested.
The Hardware Complexity Problem
Flow argues that the same shift that changed software development is now coming to hardware, but the challenge is substantially harder. A single hardware design change can ripple across mechanical, electrical, and software systems, forcing teams to coordinate updates in parallel and verify millions of requirements, constraints, and regulatory standards. According to the company, integration and verification have become too complex to be managed manually.
Agentic Platform for Hardware Development
Flow is building a platform where AI agents can continuously track changes, propagate updates across teams, and verify results in seconds. The goal is to reduce hardware iteration cycles from months to days, just as AI has transformed software development cycles. The company designed the platform for engineering teams that need to coordinate mechanical, electrical, and software changes at scale while maintaining regulatory compliance.
Customer Momentum
Since its Series A last October, Flow has added General Motors PPU, Rivian and Volkswagen's joint venture RV Tech, Anduril, Stoke Space, Intuitive Machines, and Pacific Fusion as customers. They join existing users such as Rivian, Joby Aviation, Astranis, and Radiant Industries, which use Flow as their default hardware development platform. At Rivian, Flow adoption grew from 40 to 1,500 users in seven months, and engineers now run millions of API calls each week.
Investor Perspectives
Antonio Gracias said his firm was introduced to Flow by world-class engineers it has worked alongside for years. He highlighted the market pull from trusted executives as a rare signal and a central reason for the investment. Gavin Baker added that Flow is building the operating system on which physical products are specified, verified, and eventually designed as hardware programs become more complex.
Plans for the New Capital
Flow will use the new funding to build a leading AI harness for hardware engineering, allowing frontier models to work securely with sensitive engineering data on live hardware programs. The company plans to expand review, branching, and evaluation capabilities and pursue FedRAMP authorization for regulated customers. It will also grow its engineering team across AI and systems engineering and scale its sales team to meet rising demand.
Leadership Vision
Pari Singh said every hardware company now has to decide how fast it will adopt AI, and those that move first will win their markets. He described Flow as the de facto platform for agentic hardware, with 96% of customers coming inbound. Singh added that AI is solving foundational problems in mathematics, biology, and physics, and that the ability to develop complex hardware systems in days will change the world.
The latest financing reflects growing demand for AI tools that address the complexity of modern hardware programs. Flow's platform is already used by companies in space, automotive, defense, and energy, and investor demand suggests confidence in its approach. The new capital will support the company's next phase as it expands secure AI workflows, regulatory certifications, and support for a growing customer base.