Vercel has opened Sandbox Drives in public beta: persistent storage directories that can be mounted into Vercel Sandbox runs and reused after a sandbox stops. The feature is available on Hobby, Pro, and Enterprise plans and is designed for agent workspaces, datasets, dependencies, and other files that should survive between runs.
The useful distinction is between saving a working directory and saving an entire sandbox image. Drives persist independently of an individual sandbox, but they introduce metered storage and I/O charges, region constraints, and a single-writer rule that teams should account for before building workflows around them.
How Vercel Sandbox Drives work
A Drive is mounted at a path inside a sandbox. Code running in the sandbox reads and writes files through that mount; those files remain on the Drive after the sandbox stops. A later sandbox can mount the same Drive and continue from the saved data.
That can be useful when an AI agent needs to retain a project workspace across sessions, when multiple jobs reuse a dependency cache, or when large datasets and model files should not be downloaded into every short-lived environment.
Drives versus sandbox snapshots
Vercel’s docs distinguish Drives from sandbox snapshots. A snapshot captures a sandbox filesystem and can be used to start another environment from that state. Each sandbox started from a snapshot gets its own filesystem copy. A Drive is a separate persistent directory that can be mounted into different sandboxes.
In short, use a snapshot to restore an environment and a Drive to keep data available across environments. They can be combined—for example, start from a prepared snapshot and mount a Drive for a project’s source files or dependency cache.
Sharing and write behavior
Vercel documents one read-write mount for a Drive at a time. After a Drive has been initialized with data, several sandboxes can mount point-in-time, read-only snapshots concurrently. Those snapshots do not automatically include writes made afterward; a reader needs a new snapshot to see a later state.
This is a useful fit for one agent or job updating a workspace while review, test, or analysis sandboxes read a consistent version. It is not the same as a multi-writer shared filesystem. Applications that require concurrent writes need to coordinate access or choose storage designed for that pattern.
Beta availability, limits, and pricing
Vercel says Drives are in public beta on Hobby, Pro, and Enterprise. A sandbox can mount up to four Drives. The default maximum size is 1 TiB, or 1 GiB on Hobby, with a default quota of up to 16 TiB; higher limits can be requested.
Drives remain in the region where they are created, and sandboxes that mount them must run in that same region. Vercel says those sandboxes cannot use failover regions, so region placement and resilience need to be considered together.
Pricing is based on storage, reads, and writes and varies by region. For iad1, Vercel lists storage at $0.05 per GB-month, reads at $0.0015 per GB, and writes at $0.004 per GB. Hobby includes 15 GB of Drive storage and 30 GB each of reads and writes per month. Confirm current regional rates and plan allowances before estimating production cost.
Practical design and safety considerations
Persistent storage changes the lifecycle of sandbox data: files no longer disappear when a compute environment stops. That makes retention, access scope, and deletion behavior part of the application design.
Before using Drives for an agent or deployment workflow:
- decide what data must persist and set explicit size limits;
- avoid writing credentials or sensitive customer data unless the storage and access model has been reviewed;
- separate workspaces by project, customer, and environment;
- account for read/write traffic as well as stored GB when modeling cost;
- test recovery and cleanup, noting that deleting a Drive permanently removes its data;
- confirm every sandbox using a Drive is scheduled in the Drive’s region.
The feature can simplify state continuity for sandbox-based agents, but it does not by itself provide a multi-writer database, cross-region failover, or a complete persistence strategy for an application.
What developers should evaluate
Start with a non-critical workload such as a reusable dependency cache or an agent workspace that can be rebuilt. Measure setup time, read and write volume, storage growth, and how often snapshots need refreshing. Then test interruption, sandbox replacement, and data deletion before depending on a Drive for user-facing work.
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Official sources
Frequently asked questions
What are Vercel Sandbox Drives?
Drives are persistent storage directories that can be mounted into Vercel Sandbox environments. Files remain on a Drive after a sandbox stops and can be reused by another sandbox in the same region.
Are Vercel Sandbox Drives generally available?
No. Vercel announced Drives as a public beta on September 23, 2026, for Hobby, Pro, and Enterprise plans.
Can multiple sandboxes write to the same Drive at once?
Vercel documents one read-write mount at a time. Multiple sandboxes can read point-in-time snapshots of the Drive, but later writes are not included in an existing snapshot.
How much do Vercel Sandbox Drives cost?
Pricing depends on region and includes storage, reads, and writes. In the iad1 region, Vercel lists $0.05 per GB-month for storage, $0.0015 per GB read, and $0.004 per GB written; check the current pricing page for your region and plan.
What are the main limitations of Sandbox Drives?
A sandbox can mount up to four Drives. Drives are tied to the region where they are created, and a sandbox using one must run in that region without failover regions. Hobby Drives have a 1 GiB default maximum size, compared with 1 TiB on other plans.