Major Cloud Providers Now Offer Agent Sandboxes with Varied Implementations

Cloud Providers Embrace Agent Sandboxes

AWS, Google Cloud, Microsoft Azure, and Cloudflare have all introduced agent sandboxes, enabling isolated execution environments for code. Google Cloud recently made its Cloud Run sandboxes available in public preview, following AWS's release of its version. This signifies that all four major cloud providers now offer native primitives for isolated code execution.

Diverse Isolation Technologies

Despite offering the same product shape—a platform to run untrusted code in isolation—each cloud provider has implemented its sandboxes using distinct architectural approaches. AWS utilizes Lambda MicroVMs built on Firecracker, providing dedicated virtual machines with suspend-resume capabilities. Google Cloud employs gVisor kernel interception for GKE Agent Sandbox and a lightweight isolated execution boundary within existing Cloud Run instances for its Cloud Run sandboxes.

Microsoft and Cloudflare's Approaches

Microsoft was an early adopter of this pattern, with Azure Container Apps dynamic sessions running on Hyper-V boundaries since 2024. Microsoft reported that Copilot alone uses over 400,000 of these sessions daily. Cloudflare built its Sandboxes on top of Containers, isolating each sandbox within its own VM and managing them through Workers and Durable Objects.

Google Cloud Run Implementation Details

The Cloud Run sandbox is activated via a `--sandbox-launcher` flag during deployment, which mounts a sandbox binary within the container. Applications then call this binary through a subprocess. Google charges no additional fee for this feature, as sandboxes utilize the CPU and memory already allocated to the running instance. A demonstration showed a Cloud Run service starting, executing, and stopping 1,000 sandboxes in an average of 500 milliseconds each.