VM Sandboxes: Full computers for agents | Modal Blog

Introduced VM Sandboxes as a new runtime option for Modal Sandboxes, offering a full Linux VM environment. This is built on Cloud Hypervisor and includes innovations in host filesystems, lazy image loading, memory bursting, and snapshotting. The VM runtime is designed to support agents that require traditional computer capabilities like running Docker stacks, local databases, and dev servers, while maintaining compatibility with existing Modal APIs and performance characteristics like sub-second cold starts and CPU/memory bursting.