Summary
On July 30, 2026, Vercel added multi-user isolation to its Sandbox SDK. Using createUser, createGroup, and asUser in @vercel/sandbox, each AI agent can run as its own Linux user with a private home directory inside a single sandbox, while groups allow controlled file sharing between agents.
What changed
The @vercel/sandbox SDK now supports multiple Linux users and groups within one Sandbox instance. Each agent gets an isolated user and home directory via createUser and asUser, and createGroup lets agents share files deliberately. Multi-user support is JS-SDK only and requires a sandbox image that includes /bin/bash.
Why it matters
Running several agents in a single sandbox instead of one-sandbox-per-agent cuts cold-start and resource overhead for multi-agent systems while preserving per-agent filesystem isolation. It makes Vercel Sandbox a more practical substrate for orchestrated agent fleets rather than single-agent code execution.
Evidence excerpt
Give each AI agent its own Linux user with a private home directory, and allow file sharing between agents with groups, using the @vercel/sandbox createUser, createGroup, and asUser methods. Multi-user support is available in the JS SDK only, and the sandbox image must include /bin/bash.