Fred K. Schott, co-founder of the web framework Astro, has open-sourced Flue — a TypeScript framework for building AI agents, released under the Apache-2.0 license. The kind of coding agent that can write code, run tests, and push commits doesn't just rely on a large language model. There's an entire orchestration layer beneath the surface: sandboxed environments, tool calling, session memory. Flue takes that architecture and packages it into a general-purpose framework, letting developers spin up agents with comparable capabilities in just tens of lines of TypeScript. It's the same recipe that has made platforms like Manus and Cursor worth billions, even as critics dismissed them as mere wrappers around other models.
Flue comes with a built-in virtual sandbox, so agents can execute commands and read/write files without needing a full container. When a real Linux environment is required, it can plug into Daytona or Cloudflare Containers. Sensitive keys are isolated behind a proxy layer — the agent process never sees them. When you're done building, Flue bundles everything into a single deployable unit that can run on Node.js, Cloudflare Workers, GitHub Actions, and other platforms.
Schott describes Flue as "like Astro or Next.js for agents." It's not another SDK, he says — it's a full framework. The project started life inside the Astro repository, but has now been spun out as an independent open-source project, still marked as experimental.