Filesystem Sandbox

Filesystem Sandbox is a new experimental feature in Unreal Editor 5.8 that creates a virtual filesystem inside your project's Intermediate directory to capture all asset changes made to your project through Unreal Editor. While sandboxed, asset changes are saved to a special sandbox directory tree until you explicitly persist them into your real project files — overwriting the originals with the versions you've approved for integration.

This means you can make more ambitious changes to your project without worrying about polluting your pristine project files until you've done a manual review of them.

💡 Filesystem Sandbox is experimental. You can customize how Aura uses sandboxing in Aura's Chat Settings.

How it works

When sandboxing is enabled, any asset Aura or you save is written to the sandbox directory tree rather than to your real project files. Your original files stay untouched until you accept them.

• Accept writes your changes back over the original files, integrating them into the project.
• Reject will attempt to revert changes back to its original state
• Until you persist, your real project files remain exactly as they were.

Working with source control

If you already use source control with file locking — such as Perforce or SVN — modified files will only require checkout when you accept the changes for persistence. Everything you do inside the sandbox stays out of source control until you're ready to commit to it.

Crash recovery

If you crash while in a sandbox, any modifications that were saved to the sandboxed filesystem will still be there when you return to the sandbox in a future session. Your in-progress work isn't lost.

Reviewing changes

Aura comes with an improved interface that helps you understand exactly what changed for each modified asset, so you can review confidently before persisting.

💡 For the best diff experience, it's recommended you install P4Merge. Some assets can be diffed with the tools built into Unreal Editor, but many require an external merge tool to view their differences.

Gotchas

• Detailed diffs require a configured diff tool. Viewing detailed diffs of sandboxed assets requires your editor to have a diff tool configured for some assets. A few built-in diff tools come with Unreal Editor, but many assets require an external merge tool — installing P4Merge gives the best results.
• Changes must be saved to appear. Changes do not show up in the Sandbox change list until they have been saved to the filesystem. If something seems to be missing, double-check that you don't have any unsaved files.
• Manual changes are sandboxed too. Your own manual changes will appear in the sandbox alongside changes from any tools or agents.
• C++ is not sandboxed. Sandboxing only affects assets — C++ changes are not captured.
• Missing changes after a restart? If you had changes listed in the sandbox and don't see them anymore after restarting the editor, simply re-enabling sandbox should bring them back.
• Individual file rejection is still experimental and may sometimes fail on assets with dependency chains that involve multiple changed assets. This is to prevent putting the project into an inconsistent state.
• Full level diff is not yet supported in sandbox. Levels with one-file-per-actor setups allow for actor file diffing, but diffs of levels with embedded actors or changes to world settings are not yet visualized.