Founded in 2017, engineering tool company Cirrus Labs recently announced an agreement to join OpenAI's Agent Infrastructure team, focusing on building infrastructure for agent engineering. At its inception, Cirrus Labs aimed to provide engineers in the cloud computing era with more efficient development tools and runtime environments. Without external funding, the company drove innovation around continuous integration (CI/CD), build tools, and virtualization technologies. In 2018, Cirrus launched a SaaS-based CI/CD system supporting Linux, Windows, and macOS while enabling users to integrate their own cloud environments; Tart, released in 2022, became one of the most popular virtualization solutions on Apple Silicon platforms. As AI technology evolves into the "agent engineering" phase, Cirrus Labs believes developer tools face a paradigm shift similar to that seen during the early days of cloud computing. The company stated that joining OpenAI will allow it to continue advancing next-generation development frameworks tailored for both human engineers and AI agents within cutting-edge technical ecosystems. Regarding business adjustments, Cirrus Labs announced plans over the coming weeks to adopt more permissive open-source licenses for tools including Tart, Vetu, and Orchard, along with waiving associated licensing fees. Simultaneously, the company has ceased accepting new customers for Cirrus Runners and will now serve existing clients solely under active contract terms. Its core product, Cirrus CI, is scheduled to cease operations effective June 1, 2026. Cirrus Labs described this transition as a natural progression in its corporate lifecycle, marking further extension of its technological mission toward engineering infrastructure for the AI era.