Overview
Folder Sync compares two directories and shows you the differences—which files exist only on one side, which have been modified, and which are identical. You can then synchronize selected files in either direction.
Starting a Comparison
- Navigate to the first folder in the left pane
- Navigate to the second folder in the right pane
- Go to Tools → Compare Folders (or press Cmd + Shift + C)
Captain's Deck will scan both directories and display the comparison results.
Understanding the Results
Files are color-coded based on their sync status:
| Blue (Left only) | File exists only in the left folder |
| Green (Right only) | File exists only in the right folder |
| Orange (Different) | File exists in both but content differs |
| Gray (Equal) | File is identical in both folders |
By default, identical files are hidden to focus on differences. Toggle "Show Equal Files" to see everything.
Sync Directions
For each file or selection, you can choose the sync direction:
- Copy Left → Right — Copy file from left folder to right folder
- Copy Right → Left — Copy file from right folder to left folder
- Skip — Don't sync this file
Click the direction arrows next to each file, or select multiple files and choose a direction from the toolbar.
Performing the Sync
- Review the comparison results
- Set sync direction for files you want to synchronize
- Click Synchronize to execute
Warning: Synchronization will overwrite files in the destination. Make sure you've set the correct direction before proceeding.
Bidirectional Sync
For a true bidirectional sync (newest file wins):
- Click Auto-Select in the toolbar
- Choose Newer Files Win
- Captain's Deck will automatically set directions based on modification dates
- Review the selections and click Synchronize
Selective Sync
You don't have to sync everything. Use selective sync to:
- Filter by type: Only sync certain file extensions
- Exclude patterns: Skip files matching patterns (e.g.,
*.tmp,.DS_Store) - Manual selection: Check/uncheck individual files
Comparing Individual Files
For files that exist in both folders but differ, you can see exactly what changed:
- Select the file marked as "Different"
- Click Compare Files or double-click
- View side-by-side diff (for text files) or metadata comparison
FileMerge Integration: Right-click and select "Open in FileMerge" to use Apple's diff tool for detailed comparison.
Use Cases
Backup Verification
Compare your working folder with a backup to ensure nothing is missing or out of date.
Deployment
Compare local development folder with remote server (via SFTP) to see what needs to be uploaded.
Merging Folders
Combine contents from two folders, keeping the newest version of each file.
Finding Duplicates
Identify identical files across two locations to free up disk space.
Keyboard Shortcuts
| Cmd + Shift + C | Compare folders |
| ← | Set direction: copy left to right |
| → | Set direction: copy right to left |
| Space | Toggle file selection |