Blacksmith

Blacksmith is a high-performance continuous integration (CI) platform founded in January 2024 by University of Waterloo alumni Aditya Jayaprakash (JP), Aayush Shah, and Aditya Maru. The San Francisco-based startup emerged from Y Combinator's Winter 2024 batch and has rapidly become one of the fastest-growing developer tools companies, achieving $1 million in annual recurring revenue (ARR) within one month of founding and scaling to $3.5 million ARR with over 700 customers by September 2024.

Blacksmith provides a drop-in replacement for GitHub Actions runners, delivering CI/CD pipelines that run up to 2x faster while reducing compute costs by up to 75%. Unlike traditional CI providers that rely on generic cloud infrastructure from AWS or Azure, Blacksmith operates on purpose-built, gaming-grade CPUs optimized for maximum throughput. This architectural advantage enables development teams to ship code faster, reduce wait times, and improve developer productivity without changing their existing workflows—teams can migrate by modifying just a single line of code.

The platform has attracted significant investor attention, raising $3.5 million in seed funding in May 2024 led by Google Ventures and Y Combinator, followed by a $10 million Series A round in September 2024, also led by Google Ventures. The rapid follow-on funding—completed in just 14 days and only four months after the seed round—reflects Blacksmith's exceptional growth trajectory and market validation. Notable angel investors include Spencer Kimball (CEO of Cockroach Labs), David Cramer (co-founder of Sentry), and other prominent developer tools founders. With a lean team that achieved $1 million ARR with just four people, Blacksmith is redefining CI/CD infrastructure for AI-first development teams building the next generation of software.