Blacksmith

Blacksmith Software Inc. sells continuous integration compute: it runs a software team's existing GitHub Actions workflows on its own machines instead of the runners GitHub hosts. Teams switch by changing the runner label in the runs-on line of a workflow, so the build and test definitions stay where they are. The company says more than 10,000 organisations use it and that it processes more than 90 million CI jobs a week.

What the product does

Jobs run in instantly provisioned microVMs on bare-metal machines chosen for high single-core performance, which Blacksmith says makes them twice as fast as GitHub's runners at 60% lower cost. Docker layers are kept on NVMe drives between runs and Docker image pulls are cached, and dependency caches sit in the same data centre as the jobs, which it says makes cache downloads four times faster. Concurrency is unlimited. A console makes the pipeline observable, with search across CI logs, detection of slow and failing jobs, and failed-test output posted as comments on pull requests.

Who it serves

The service is aimed at engineering teams whose CI queues have grown with their codebase and, increasingly, with code written by AI agents. Customers it names include Mercury, Granola, Handshake and LangChain on its funding announcement, and Vercel, Clerk and Supabase on its site. New accounts get 3,000 free minutes a month without a credit card, and the site displays a SOC 2 badge.

Key facts

Legal name: Blacksmith Software Inc. Chief executive and co-founder: Aditya Jayaprakash Infrastructure: just under 10 MW of its own compute in US and European data centres, with plans to grow it fivefold in 2027 Hiring: New York and San Francisco Funding: Series C announced 21 October 2026 at a $1 billion valuation, led by Sequoia Capital with Premji Invest, Peak XV Partners, GV and Y Combinator; $125 million raised in total