Blacksmith has raised a $45 million Series B led by Peak XV Partners at a $550 million valuation, with GV and Y Combinator participating, bringing total funding to $58.5 million and marking a near-tenfold jump from the roughly $60 million valuation it had less than a year earlier. Founded in 2024, the startup says adoption has surged as AI coding tools make it easier to generate software while leaving validation as a key bottleneck, lifting its customer base to more than 5,000 from about 700 over the same period and pushing revenue into the tens of millions of dollars. Blacksmith began as a cloud provider for continuous integration workloads and has expanded with Codesmith, an AI agent that can automatically fix failed code checks, while some of its largest customers now spend more than $1 million a year. Earlier company disclosures cited more than 6,000 businesses using the platform and annual recurring revenue of $3.5 million in September 2025, highlighting how quickly the figures have been changing as Blacksmith broadens its tooling and invests in more compute capacity.