Cloudflare adds runtime sandbox selection and filesystem snapshots

Cloudflare has reworked Containers for agent workloads, letting application code select sandbox images and instance types at startup and adding filesystem snapshots in public beta. Under the durable_object scheduling policy, those choices move from deployment settings to the code handling each task. ComputeSDK’s independent benchmark measured median startup at 648 milliseconds, down from just over four seconds on the previous scheduling path. Snapshots let teams save a prepared workspace and restore its files when a session resumes. They can also provide a shared baseline for multiple sandboxes, a pattern Cloudflare says can help keep evaluation environments consistent. For agent builders, a workspace can pick up from a saved state later, while compute stops during pauses. Filesystem snapshots are in public beta; runtime selection requires setting the scheduling policy and declaring images the Durable Object can choose from.