Blacksmith Raises $66M Series C From Sequoia at $1B Valuation on AI Code Testing Surge

Continuous integration startup Blacksmith raised a $66M Series C led by Sequoia Capital at a $1B valuation, nearly doubling its $550M valuation from a $45M Series B led by Peak XV Partners about two months ago in August and bringing total funding to about $124.5M. Blacksmith now runs 90M weekly validation checks across more than 10,000 companies—up from 5M weekly checks at the start of the year and about 5,000 companies in August—driving a 17x increase in annual recurring revenue into the tens of millions, with its largest customers spending over $1M annually. Founded in 2024 by CEO Aditya Jayaprakash, the company operates tens of thousands of its own servers installed in global data centers rather than renting capacity from AWS, Google Cloud, or Microsoft Azure, and plans to use most of the new capital to buy more computing power while expanding headcount from about 40 to around 75 by year-end. Rapid adoption of AI coding assistants has shifted engineering bottlenecks toward automated testing; Jayaprakash noted that Blacksmith's continuous integration volume jumped 40% when Anthropic launched Claude Fable 5 in July, while Anthropic reported last month that its own validation workloads grew 25-fold in six months. "AI coding tools like Cursor, OpenAI’s Codex and Anthropic’s Claude Code have made the first half 'extremely easy,' he said. 'But now the bottleneck has shifted to the second piece, which is: how do I actually validate all this code?'" — Aditya Jayaprakash, Cofounder and CEO of Blacksmith.