Blacksmith, a San Francisco company that runs the infrastructure used to build and test code before it is merged, has raised a $66m Series C led by Sequoia Capital at a $1bn valuation. It announced the round on 21 October 2026.
Premji Invest joined as a new investor, and existing backers Peak XV Partners, GV and Y Combinator also took part. The company said the round takes its total funding to $125m.
The new valuation is almost twice the $550m at which Blacksmith raised its Series B in August, TechCrunch reported.
“We're grateful to our customers who are trusting us to solve this bottleneck, and excited to partner with Sequoia to solve it at scale.”Aditya "JP" Jayaprakash, Co-founder and CEO, Blacksmith
What Blacksmith does
Blacksmith sells compute for continuous integration, or CI, the stage in software development where each code change is automatically built and tested. The company argues that AI coding agents have moved the bottleneck in shipping software from writing code to checking it, and that general-purpose cloud servers handle CI poorly because demand swings so sharply.
A single customer's CI load can go from nothing to tens of thousands of processors and back, the company said. Customers move their jobs to Blacksmith by changing one line in a workflow file, and on average those jobs finish twice as fast and cost 60% less, according to the company.
More than 10,000 companies now run CI on Blacksmith, including Ashby, Granola, Handshake and LangChain. An infrastructure engineer at LangChain said in the release that its runner costs fell by about 40%. TechCrunch also named Mercury as a customer.
Growth since January
The number of CI jobs running on Blacksmith each week rose from 5 million in January to more than 90 million, and annual recurring revenue grew 17 times over the same period, the company said. It did not disclose a revenue figure.
In a blog post about the round, the company pointed to Anthropic, which reported last month that its CI volume had grown 25-fold in six months. Blacksmith said it sees the same trend among its own customers.
Isaiah Boone, a partner at Sequoia, said the founders had seen early that the tools for building and testing code would have to change as AI agents wrote more of it.
The funding so far
Blacksmith was founded in 2024 by Aditya "JP" Jayaprakash, its chief executive, with Aayush Shah and Aditya Maru. The three met as undergraduates at the University of Waterloo. Shah and Maru were early engineers at Cockroach Labs, and Jayaprakash was an engineer at Faire.
In August 2026 the company raised a $45m Series B led by Peak XV Partners, which valued it at $550m, TechCrunch reported at the time. That round followed a $10m Series A at a $60m valuation less than a year earlier. TechCrunch said in August that the company had grown to about 30 employees.
Blacksmith said the new money will go into hiring and more compute. It manages nearly 10 MW of computing capacity in data centres in the US and Europe and plans to grow that at least fivefold in 2027. It is hiring engineers in New York and San Francisco.
Company website: blacksmith.sh