Flow Engineering raises $50M Series B at $750M for AI agents on hardware programs

San Francisco-based Flow Engineering said Wednesday it raised a $50 million Series B at a $750 million valuation for its agentic platform that keeps CAD, simulation, code, and test aligned as hardware teams iterate.

Software teams already ship with agents, while hardware teams still spend months reconciling drawings, simulations, and requirements by hand. Flow’s raise is a bet that the same loop can shorten that cycle for cars, rockets, and defense hardware without dropping the checks that keep a design consistent.

On Wednesday, 30 September 2026, Flow Engineering said it raised a $50 million Series B at a $750 million valuation. A Series B is a later round of venture funding, after a company’s earlier rounds. The $50 million is the new money. The $750 million is the price this round puts on the whole company, not the cash that changed hands. Antonio Gracias, founder of Valor Equity Partners, and Gavin Baker, managing partner at Atreides Management, co-led the round. Sequoia Capital, which led Flow’s Series A, took part, along with Human Capital, Evantic, SV Angel, Odyssey, and EQT. The release also names contributions from Hugging Face co-founder Thomas Wolf, Mercedes-Benz chief information officer Jonas von Malottki, and Formula 1 world champion Nico Rosberg. Roelof Botha joined the board as an independent director and personally invested. PR Newswire carries the release at 11:00 a.m. Eastern. The dateline is San Francisco. Flow’s blog posts the same release the same day. Those lines are Flow’s.

Flow calls itself the agentic platform for hardware development. Agentic, here, means the software takes the next step on a change, rather than only answering a question. The company says teams get a living system of record that connects requirements, CAD, simulation, code, and test. CAD is the computer drawing of a physical part. A system of record is the copy the team treats as the current truth. On top of that record, Flow says its agents watch an engineering change, find what else the change touches, and check that requirements and tests still cover the work. The release says one hardware change can ripple across mechanical, electrical, and software systems, and that the whole machine still has to meet millions of requirements, including regulatory standards. Flow’s stated goal is to cut a hardware iteration from months to days. Those lines are Flow’s. The release does not print a timed before-and-after for a named program.

Since its Series A last October, Flow says it has added General Motors PPU, the Rivian and Volkswagen joint venture RV Tech, Anduril, Stoke Space, Intuitive Machines, and Pacific Fusion. They join customers the release already names: Rivian, Joby Aviation, Astranis, and Radiant Industries, which Flow says use the product as their default hardware platform. The about box says thousands of engineers at companies including Rivian, Anduril, Joby, Astranis, and Radiant are building on Flow. The company blog’s about box adds General Motors to that sentence. Those names are Flow’s. The release does not print a contract value, and it does not say an outside firm confirmed the list.

Flow says use at Rivian grew from 40 people to 1,500 in seven months, and that Rivian engineers now run millions of API calls each week. An API call is one program asking another program for data. Seven months is a bit more than half a year. Forty to 1,500 is roughly 37 times as many people. Scott Mackenzie, Rivian’s director of product development, process and tools, is quoted: “We evaluated 30 tools and nothing came close to Flow. It allows Rivian to develop faster, safer and better by bringing a collaborative approach to systems engineering.” That quotation is his, in the Flow release. The user count and the call count are Flow’s. The release does not say an outside auditor checked them.

Pari Singh, founder and chief executive, said every hardware company now has to decide how fast it will adopt AI, and that the ones that move first will win their markets. He said 96 percent of customers come to Flow inbound, and that category leaders in space, automotive, defense, and energy build on Flow. Inbound, here, means the customer came to Flow, rather than the other way around. Ninety-six percent is Flow’s share of its own customer list. The release does not print the count behind that percent.

Flow says the new money will pay for an AI harness so frontier models can work on sensitive engineering data inside live hardware programs. A harness, here, is the set of controls around a model: which files it can see, and what it is allowed to change. The company says it will expand review, branching, and evaluation. Branching, here, means trying a design change on a copy before that copy becomes the one the team treats as current. It also plans to hire in AI and systems engineering, pursue FedRAMP authorization and other certifications for regulated customers, and grow the sales team. FedRAMP is the U.S. government program a cloud product goes through before federal agencies can buy it. Pursue means that authorization is still ahead. Those lines are Flow’s. The release does not name a federal customer, and it does not print revenue.

The release sketches the two co-leads in its own words. It says Gracias was an early investor in Tesla and serves on the boards of SpaceX and Neuralink, and that Valor has also backed Anduril. It says Baker was an early investor in Nvidia, Tesla, xAI, and SpaceX. Gracias is quoted on demand he saw from engineers he already knew. Baker said Flow is building the system on which physical products are specified, verified, and eventually designed, using software in place of scarce engineering time. Those lines are in the release.

The picture is Flow’s homepage on the day of the announcement. A blue banner across the top reads “Flow raises $50M Series B at a $750M valuation, co-led by Antonio Gracias (Valor) and Gavin Baker (Atreides),” with a Learn More button. The headline reads “Engineered for hardware teams. That build at agent speed.” Beside it, the page says requirements management and AI agents continuously align CAD, simulation, code, and test, and calls the product a living system of record for hardware development. Two buttons read Book Demo and Start Trial. A row of marks shows Joby, Skydio, Astranis, and Stoke. It is the company’s own page. It is not a photograph of a factory, and the banner does not print a calendar date.

In plain terms, Flow said on Wednesday that it raised $50 million at a $750 million valuation so AI agents can keep a hardware program’s requirements, drawings, simulations, code, and tests in step. The customer names, the Rivian user count, and the 96 percent inbound line are Flow’s.