Blacksmith Raises $45 Million as Valuation Jumps Nearly 10X

Blacksmith has raised $45 million in fresh funding as the software testing startup looks to capitalise on a growing challenge created by AI coding tools: developers can generate code faster than ever, but that code still needs to be tested and validated.

Peak XV Partners led the Series B and values Blacksmith at $550 million. That is nearly 10 times the $60 million valuation the startup received when it raised a $10 million Series A less than a year ago.

Existing investors GV and Y Combinator also participated in the new financing, bringing Blacksmith’s total funding to $58.5 million.

Blacksmith grows to more than 5,000 customers

Founded in 2024, Blacksmith provides infrastructure that helps software teams build, test and verify code before deploying it into production. The company now serves more than 5,000 customers, compared with fewer than 700 less than a year ago.

Its customers include Mercury, Supabase, Clerk, Ashby and Expensify, according to co-founder and CEO Aditya Jayaprakash.

The startup’s growth comes as AI coding products, including Cursor, OpenAI’s Codex, and Anthropic’s Claude Code, make it easier for developers to generate more software. Faster code creation, however, does not eliminate the need to determine whether that code works correctly.

“Validating code is still a bottleneck, and it's an even bigger bottleneck because people are writing even more,” Jayaprakash said.

Blacksmith expands beyond continuous integration

Blacksmith initially focused on providing cloud infrastructure for continuous integration, or CI, workloads. These systems run software builds and automated tests that help developers identify problems before code reaches production.

The company has since expanded its platform to include Codesmith, an AI coding agent designed to fix failed code checks automatically. Prakash said Blacksmith reached a $10 million annualised revenue run rate with a team of only 10 employees. The company has since expanded to about 30 employees, while revenue has grown to what he described as tens of millions of dollars.

He declined to disclose a more precise current annual recurring revenue figure but said some of Blacksmith’s largest customers are now spending more than $1 million annually on the platform.

AI code testing becomes increasingly competitive

Blacksmith faces competition from established developer platforms and a growing collection of AI coding companies. Alternatives include GitHub Actions, Cursor Automations and validation capabilities incorporated into Codex and Claude Code.

Major cloud providers, including Amazon Web Services, Microsoft Azure, and Google Cloud, also offer software testing and development services, while numerous startups are targeting different parts of the AI coding workflow.

Jayaprakash said Blacksmith aims to differentiate itself through faster code testing and lower costs. The company plans to use its growing platform to expand beyond testing into a broader collection of tools designed to help developers write, validate and merge software more quickly.