AI code-testing startup Blacksmith has raised $45 million in a Series B funding round led by Peak XV Partners. The funding increases the startup's valuation to $550 million, up from $60 million when it raised its $10 million Series A less than a year ago.

Existing investors GV and Y Combinator also participated in the round, bringing Blacksmith's total funding to $58.5 million. Founded in 2024, the platform helps companies build, test, and verify software before it reaches production.

• Customer Growth: Blacksmith serves more than 5,000 customers, including Mercury, Supabase, Clerk, Ashby, and Expensify, up from over 700 less than a year ago.
• Team & Revenue: The company grew from 10 employees at a $10 million annualized revenue run rate to about 30 employees with revenue reaching "tens of millions of dollars."
• Customer Spend: Some of its largest customers spend more than $1 million annually on the platform.

While AI coding tools such as Cursor, OpenAI's Codex, and Anthropic's Claude Code make generating code easier, code quality remains an issue. Co-founder and CEO Aditya Jayaprakash noted that code validation has become an even larger bottleneck as developers write more code.

Blacksmith originally launched as a cloud provider for continuous integration (CI) workloads to run software builds and tests. The startup has since expanded its platform with Codesmith, an AI coding agent designed to automatically fix failed code checks.

The startup competes on speed and affordability against GitHub Actions, Cursor Automations, validation tools in Codex and Claude Code, along with cloud services from Amazon Web Services, Microsoft Azure, and Google Cloud. Looking ahead, Blacksmith plans to expand into a broader suite of tools to help developers write, validate, and merge software faster.