Vercel Sandbox now supports FUSE-based filesystems
By Steven Van ·
Vercel Sandbox can mount S3 buckets and other FUSE-compatible storage as a local filesystem path, using sudo to install the driver.
Vercel Sandbox now supports FUSE (Filesystem in Userspace) drivers, so a running Sandbox can mount remote storage such as an S3 bucket, a network filesystem, or another FUSE-compatible driver as a regular path. Code inside the Sandbox then reads and writes through that path instead of calling a storage API directly.
The docs walk through mounting an Amazon S3 bucket with Mountpoint, the official FUSE driver for S3: install the driver, create a mount directory, then mount the bucket. Because FUSE runs as a system-privileged process, the install and mount commands run with sudo.
- Stream large datasets directly from object storage without copying them into the Sandbox first.
- Share state across Sandboxes through a common filesystem.
- Run tools that expect POSIX paths against remote sources.
Mounting this way exposes AWS credentials inside the Sandbox for the life of the process, so Vercel recommends a narrowly scoped, short-lived IAM role. To keep credentials out of the Sandbox entirely, the docs also show routing S3 requests through a proxy that signs them with a Vercel Function instead.