Blacksmith, a startup that uses artificial intelligence to help engineering teams validate code, has raised $45 million in Series B funding as software development enters a new era defined by AI-generated code. The round was led by Peak XV Partners, with participation from existing investors GV and Y Combinator, bringing Blacksmith’s total funding to $58.5 million.
The investment values Blacksmith at $550 million, nearly ten times the $60 million valuation assigned when the company raised a $10 million Series A less than a year ago. The rapid increase reflects strong demand for infrastructure that can test and verify software at the speed modern AI coding tools demand.
Key facts from the announcement
- Funding amount: $45 million Series B
- Lead investor: Peak XV Partners
- Valuation: $550 million, up from $60 million less than a year ago
- Total funding: $58.5 million
- Founded: 2024
- CEO: Aditya Jayaprakash
- Customers: more than 5,000, including Mercury, Supabase, Clerk, Ashby, and Expensify
- Core product: Codesmith AI coding agent
The code validation challenge
AI coding tools such as Cursor, OpenAI’s Codex, and Anthropic’s Claude Code have made it dramatically easier for developers to generate code. But generating code is not the same as delivering reliable software. Every change still needs to be built, tested, checked for regressions, and verified before it is released to production.
In an era of AI-generated code, the number of commits and proposed changes tends to rise sharply. This creates a new bottleneck: validation. “Validating code is still a bottleneck, and it’s an even bigger bottleneck because people are writing even more,” said Jayaprakash.
Blacksmith focuses on exactly this problem. Its platform helps companies build, test, and verify software before it reaches production, allowing teams to catch issues early and prevent broken code from affecting users.
From CI infrastructure to AI agents
Blacksmith was founded in 2024. It started as a cloud provider for continuous integration (CI) workloads, helping companies run builds and automated tests efficiently. The company soon expanded beyond infrastructure with Codesmith, an AI coding agent that can automatically fix failed code checks.
Codesmith marks a shift in Blacksmith’s positioning. Instead of only providing the environment where tests run, Blacksmith now actively participates in repairing code when tests fail. This makes the platform more useful to engineering teams who want to reduce manual debugging and move faster from commit to deployment.
By combining CI infrastructure with AI-powered fixes, Blacksmith aims to offer a complete validation layer for the AI era of software development. The company wants to be the place where code goes to be checked, fixed, and finalized before release.
Rapid growth in customer adoption
Blacksmith says it now serves more than 5,000 customers, up from more than 700 customers less than a year ago. Among its customers are Mercury, Supabase, Clerk, Ashby, and Expensify. These companies use Blacksmith to validate code across their development workflows, from small teams to larger engineering organizations.
Revenue growth has also been strong. Jayaprakash said Blacksmith reached a $10 million annualized revenue run rate with just 10 employees. Today, the company has about 30 employees and revenue has grown to “tens of millions of dollars.” Some of its largest customers spend more than $1 million a year on the platform, he noted.
The gap between employee count and revenue is particularly noteworthy. Blacksmith appears to have built a highly efficient business, using automation and AI to serve thousands of customers without needing a large sales or services organization.
A crowded and competitive market
Blacksmith operates in a crowded market with strong incumbents and ambitious startups. Key competitors include GitHub Actions, Cursor Automations, validation capabilities built directly into Codex and Claude Code, and AI code-testing services from Amazon Web Services, Microsoft Azure, and Google Cloud. There are also many smaller startups trying to solve similar problems.
Large cloud providers have the advantage of deep ecosystem integration. If a company already uses GitHub and GitHub Actions, for example, adding another testing layer might be less appealing. Similarly, developers who rely on Cursor or Claude Code may expect validation features to come from those tools themselves.
Blacksmith is trying to differentiate through speed and affordability. The company argues that its specialized infrastructure can run code tests faster and at lower cost than general-purpose CI services. This is important as AI-generated code increases testing volume and pushes up cloud bills.
Investor confidence in AI infrastructure
The Series B led by Peak XV Partners reflects a broader trend of venture capital flowing into tools that support AI-assisted development. While AI model companies have captured large amounts of capital, investors are also betting on the infrastructure layer around those models, including code testing, observability, and security.
GV and Y Combinator’s continued participation signals confidence from early backers. Y Combinator, in particular, has supported Blacksmith since its formation and has seen the company grow from a CI-focused startup into a broader AI coding platform.
The jump in valuation from $60 million to $550 million in less than a year is extraordinary by historical standards. It shows how much investor sentiment has shifted toward the software development lifecycle in an AI-centric world. Valuation growth of that magnitude is rare outside the AI model layer itself.
What the funding will be used for
Blacksmith plans to use the new capital to expand into a broader suite of coding tools. According to Jayaprakash, the company aims to help developers write, validate, and merge software faster. This suggests Blacksmith is moving beyond testing into areas like code generation, code review, and merge automation.
The company is expected to continue investing in Codesmith and its CI platform, while also
Source:TechCrunch News