Trellis File Manager

Trellis shows folders as panes on a canvas, joined by lines from a folder to its child. Open a folder and you keep the last one: it sits right next to it, and the way there is visible.

That is the whole difference to Finder, and it carries further than it sounds. Moving files between two folders means dragging, not copy, switch tab, paste. Comparing two folders means putting them side by side and letting them colour themselves. Searching and keeping the result means leaving the hits on the canvas as their own pane.

ARRANGEMENT Tree to the right for deep paths, tree downwards for wide fan-out, star with the roots in the middle. Panes visibly move to their new places when you switch, and the lines stay attached. Every branch carries its colour, and where it sits on the pane is up to you.

ITS OWN INDEX Trellis keeps a database of the folders you opened and answers sizes, search and comparison from it. A folder's size is there at once instead of after thirty seconds of counting, and the size view shows what takes the space.

EXTERNAL DRIVES An index is worth the most when the drive is not plugged in. Trellis remembers the structure, and on request previews and the text of the PDFs. Search finds the file on the stick in the drawer and tells you which drive to plug in.

CLOUD FOLDERS Dropbox, OneDrive, Google Drive, Box, pCloud and Proton Drive each put one folder per account on the disk as soon as their own app runs. Trellis finds them and asks once per account whether to show and to index it; it connects to nothing and wants no password. What sits in the cloud undownloaded it recognises as a placeholder and will not pull down by accident. iCloud Drive is one of them.

COMPARE FOLDERS Select two folders and both colour themselves: green for what exists on one side only, orange for same name but different. Computed from the index, without reading a single file.

DUPLICATES Files of equal size get read and compared, the checksums stay in the index. The second pass over the same folder is almost free. The last copy of a group cannot be ticked, so both can never disappear.

SELECTION ACROSS FOLDERS ⌘-click gathers files from several folders, or put them on the shelf, then copy, move, rename or group them in one go. Finder cannot do this, because it only ever shows one folder.

BATCH RENAME Search and replace, plain or as a regular expression, numbering, prefix and suffix, with a preview before it runs, across folder boundaries, and undo with ⌘Z.

GALLERY The images, films and PDFs of the focused pane in the right column, one to six per row. Clicking a file in the pane scrolls the gallery to it, and the other way round. Pin it to a folder and it opens there by itself.

IMAGES AND PDFS Convert to JPEG, PNG, HEIC, TIFF, WebP or PDF, resize, reduce file size. The sheet shows what comes out before anything is written: 4.2 MB becomes about 780 KB. The original stays put.

THE WAY IN Open in Trellis sits in Finder's context menu and toolbar, folders open via Open With, and the trellis:// address opens them from Shortcuts, scripts and the terminal.

TRASH Open and look inside, empty it, and put back what Trellis itself moved there. This takes Full Disk Access, granted once and voluntarily, because macOS does not let the open panel into the trash.

ALSO Copying with byte progress and undo, compress and expand, look inside an archive without unpacking it, applications in the toolbar as drop targets, new files from templates, tags and Quick Actions, lock and permissions, terminal and editor at the folder, workspaces, tabs, multiple windows.

YOUR DATA STAYS HERE Trellis collects nothing, transmits nothing and has no account. The index is a file on your Mac. The app only gets access to the folders you hand it yourself.

TRY AND BUY Fourteen days fully usable, then a one-time unlock. No subscription. After it expires everything stays readable; anything that writes to disk waits for the unlock.