Blacksmith raises $45M to solve the AI-code validation bottleneck

AI coding tools like Cursor, Codex, and Claude Code have made it easier than ever to generate code—so easy, in fact, that the industry's new bottleneck has become validation. That's the problem Blacksmith is attacking, and investors are betting big that the company's approach will stick. The startup announced a $45 million Series B led by Peak XV Partners, valuing the company at $550 million—a tenfold jump from its $60 million valuation less than a year ago. Existing investors GV and Y Combinator also participated, bringing Blacksmith's total funding to $58.5 million.

Blacksmith, founded in 2024, began as a cloud provider for continuous integration (CI) workloads, helping companies run builds and tests before code reaches production. Since then, it has expanded into AI-powered validation with Codesmith, an agent that can automatically fix failing checks. The company now serves more than 5,000 customers—up from 700 a year ago—including Mercury, Supabase, Clerk, Ashby, and Expensify. Co-founder and CEO Aditya Jayaprakash told TechCrunch that the company has reached a "tens of millions" annualized revenue run rate with just 30 employees, and some customers spend more than $1 million a year.

The core problem Blacksmith addresses is familiar to any developer using AI tools: generated code might look plausible, but it doesn't actually work—or worse, it introduces subtle bugs. "Validating code is still a bottleneck, and it's an even bigger bottleneck because people are writing even more," Jayaprakash said. By focusing on speed and affordability, Blacksmith aims to stand out in a crowded field that includes GitHub Actions, Cursor Automations, and validation features baked into OpenAI's and Anthropic's tools. The company plans to expand into a broader suite of coding tools, helping developers write, validate, and merge software faster. Whether it can maintain its momentum remains to be seen, but the valuation jump suggests investors believe validation is the next big battleground in AI-assisted development.