# Durable filesystems

> Keep a Sandbox’s files through pause and resume, and copy them into new Sandboxes with a snapshot.

Pause and resume a Sandbox without losing its local files. When you snapshot it, each clone starts with the files captured on its disk. Use an S3-backed persistent mount when different Sandboxes need the same backing files.

## Choose the right filesystem

| Need                                             | Use                                      | What it gives you                                                                                                  |
| ------------------------------------------------ | ---------------------------------------- | ------------------------------------------------------------------------------------------------------------------ |
| Keep a sandbox's own files as its work continues | The sandbox filesystem                   | Pause and resume keep the same files. A snapshot captures disk state, and a clone starts with that captured state. |
| Let different sandboxes use the same files       | An S3-backed persistent filesystem mount | A filesystem that spans sandbox boundaries.                                                                        |

A sandbox's own filesystem and a shared mount solve different problems. Use the sandbox filesystem for work that belongs to one sandbox, such as generated code, installed dependencies, or a working directory. Use an S3-backed persistent mount when separate sandboxes need access to the same files, such as shared inputs or artifacts.

## Keep work across lifecycle changes

**Pause and resume.** Pause a sandbox when work needs to wait. Its files remain available when the sandbox resumes.

**Snapshot and clone.** A user snapshot captures the sandbox's filesystem. Create a new sandbox from that snapshot when you need the saved files. The original sandbox keeps running.

**Clone.** Create another sandbox from a ready snapshot, including the filesystem state it captured. This lets you branch work from a prepared environment. Later writes to the original sandbox do not change that snapshot.

A durable workflow can coordinate these operations and show sandbox activity in its trace. Keep the files your task needs as you pause, restore, or clone sandbox work. See [Snapshots and restore](/docs-markdown/sandboxes/features/snapshots-and-restore), [Cloning](/docs-markdown/sandboxes/features/cloning), and [Managed lifecycle](/docs-markdown/sandboxes/features/managed-lifecycle) for the related controls.

## Share files across sandboxes

S3-backed persistent filesystem mounts let separate sandboxes use a filesystem beyond any one sandbox's lifecycle. For example, one sandbox can prepare a dataset and other sandboxes can use that dataset in separate tasks. Mount setup, concurrent access, and write visibility need product confirmation before this page can give procedural guidance.