# Modal Sandboxes

> Modal Sandboxes isolate agent code using gVisor plus Linux namespaces rather than hardware-level microVMs, and support GPU-backed containers with per-second billing; the platform is proprietary, while the modal-client SDK is Apache-2.0.

Managed container-based sandboxes on Modal, isolated with gVisor.

- **Category:** Execution Sandbox
- **License:** Proprietary (platform); modal-client SDK is Apache-2.0
- **Language:** Python (SDK)
- **Self-hosted:** No
- **Last verified:** 2026-10-04

> Caveat: Managed-only: no self-hosted option. Isolation is gVisor-based, which is weaker than hardware virtualization.

Source: https://agent.c8.fit/tools/modal-sandboxes/