# Folders on This Mac

Add a folder that stays on your Mac. Folder keeps node_modules out of Dropbox and Time Machine, and copies the folder before each Claude Code session.

A folder that stays where it is. No account, no upload.

## Add a Folder

On the first screen, or File › Add a Folder… (⌘N), choose On This Mac and pick any folder. The files stay where they are, and nothing is uploaded. A folder inside Dropbox or iCloud Drive is fine, and is the usual case.

The window lists the folder's files like Finder's list view: open, Quick Look (Space), rename (Return), duplicate, move to the Trash, Get Info, and drag in and out.

## Leave Build Folders Out of Sync and Backups

A switch in the Add sheet and in Folder Settings › Sync and Backups, on unless you turn it off. Build output, downloaded packages and caches inside the folder (`node_modules`, `DerivedData`, `.next` and the like) stay on this Mac, and Folder marks them so other tools skip them:

- Dropbox (`com.dropbox.ignored`)
- Time Machine (`com.apple.metadata:com_apple_backup_excludeItem`)
- File Provider sync (`com.apple.fileprovider.ignore#P`)

New build folders are marked as they appear. Nothing is moved or deleted, and nothing else is written into the folder; a `.git` folder is never marked. Turning the switch off removes the marks.

## A Copy Before Each Claude Code Session

For people who use Claude Code, Folder can copy the folder before each session starts and list what the session changed, so any of it can be put back. See [Claude Code](/docs/claude-code).

Source: https://folder.dev/docs/on-this-mac