Blacksmith, an AI code-testing startup founded in 2024, has raised $45 million in Series B funding led by Peak XV Partners, with participation from GV and Y Combinator.

The round values the company at $550 million—nearly a 10x increase from the $60 million valuation assigned during its $10 million Series A less than a year ago. Total funding now stands at $58.

5 million.

Blacksmith helps companies build, test, and verify software before production, starting as a cloud provider for continuous integration (CI) workloads and later expanding with Codesmith, an AI coding agent that automatically fixes failed code checks.

The startup now serves over 5,000 customers, including Mercury, Supabase, Clerk, Ashby, and Expensify, up from more than 700 customers less than a year ago.

Co-founder and CEO Aditya Jayaprakash said Blacksmith reached a $10 million annualized revenue run rate with just 10 employees, and has since grown its workforce to about 30 and revenue to “tens of millions of dollars.

” Some of its largest customers now spend more than $1 million a year on the platform.

The article notes that the rise of AI coding tools like Cursor, OpenAI’s Codex, and Anthropic’s Claude Code has made code generation faster, but validating code quality remains a bottleneck.

Blacksmith operates in a crowded market with competitors including GitHub Actions, Cursor Automations, and validation capabilities from major cloud providers.

Jayaprakash said the startup competes on testing speed and affordability.

Looking ahead, Blacksmith plans to expand into a broader suite of coding tools to help developers write, validate, and merge software faster.