CLOUDFLARE’S Dynamic Workers introduce a lean sandbox called the Dynamic Worker Loader, which lets a Cloudflare Worker instantiate a new, isolated Worker with runtime-provided code, all on the fly. The feature is in open beta and available to all paid Workers users, enabling agents to run code in their own sandbox while being given access to specific APIs and the option to block internet access.
Dynamic Workers use isolates—the lightweight V8 JavaScript engine concept underpinning Cloudflare Workers—so starting an isolate takes milliseconds and uses only a few megabytes of memory, roughly 100x faster and 10x-100x more memory efficient than typical containers. They support JavaScript by default, with Python and WebAssembly possible, and developers can define external APIs via TypeScript interfaces to keep the surface area secure and concise.
The article also highlights security hardening and tooling, including Code Mode for model-generated code, bundling with @cloudflare/worker-bundler, and file manipulation via @cloudflare/shell, all designed to speed up AI-driven automation while preserving isolation. Pricing during the beta is waived but normally charges $0.002 per unique Worker loaded per day, with a note to check current Dynamic Workers pricing. 24 March 2026