Blacksmith Raises $45M Series B at $550M Valuation to Scale AI Code Testing

Blacksmith Raises $45 Million Series B

AI code-testing startup Blacksmith has raised $45 million in Series B funding at a $550 million valuation to expand its platform for building, testing, and validating software.

The round was led by Peak XV Partners, with existing investors GV and Y Combinator also participating. The funding brings Blacksmith's total capital raised to $58.5 million.

The company's valuation has increased from $60 million less than a year ago, when it raised its $10 million Series A.

AI Coding Creates a Bigger Testing Challenge

Blacksmith is focused on the software testing and validation challenges created by the rapid adoption of AI coding tools.

Platforms such as Cursor, OpenAI Codex, and Anthropic's Claude Code have made it easier for developers to generate software, but the resulting code still needs to be tested and validated before reaching production.

Blacksmith CEO Aditya Jayaprakash says code validation remains a bottleneck as development teams produce more software.

From CI Infrastructure to AI Coding Agents

Blacksmith was founded in 2024 and initially operated as a cloud provider for continuous integration (CI) workloads.

Its platform helps companies run the builds and tests required to validate software before deployment.

The company has since expanded its platform with Codesmith, an AI coding agent designed to automatically fix failed code checks.

Growing Customer Base

Blacksmith now serves more than 5,000 customers, up from more than 700 customers less than a year ago.

Its customers include Mercury, Supabase, Clerk, Ashby, and Expensify.

The company says it reached a $10 million annualized revenue run rate with 10 employees and has since grown to around 30 employees and tens of millions of dollars in revenue.

Some of its largest customers now spend more than $1 million annually on the platform, according to the company.

Competition in AI Code Testing

Blacksmith operates in a competitive market that includes GitHub Actions, Cursor Automations, AI-powered validation capabilities from Codex and Claude Code, and cloud-based offerings from Amazon Web Services, Microsoft Azure, and Google Cloud.

The company says it differentiates itself through faster code testing and affordability.

Funding to Expand Developer Tools

Blacksmith plans to use its new funding to expand beyond code testing into a broader suite of coding tools.

The company aims to help developers write, validate, and merge software more quickly as AI continues to increase the volume of code being produced.