File Watching

Peekdown watches open files for changes made by other applications. When a file changes on disk, a notice appears under the toolbar — or the document reloads automatically, if you prefer.

External Changes

Choose how Peekdown responds in Settings > Behavior > When a file changes externally:

  • Show a notice — A banner appears under the toolbar: "Another app changed this file." Show Changes shows what changed, Update loads the new version, and ✕ dismisses the notice.
  • Reload automatically — The document updates on its own. Best for a live preview workflow where you edit in another app.

When the document is updated with changes from outside — automatically or via Update — the banner reads "Another app changed this file. The document has been updated." and offers Show Changes, a diff of what came in. The same diff is available from File > Show Changes… even after you dismiss the banner; both go away once you start editing. A manual ⌘R reload stays quiet unless it pulls in a pending external change.

If you have unsaved edits, Peekdown never reloads on its own: in both modes the banner warns you, and Show Changes opens the conflict dialog. See Conflict Resolution below.

Comparing Unsaved Changes

When your unsaved edits and the file on disk diverge — for example, an AI tool rewrote the file while you were editing — Peekdown shows you what's different before you choose:

  • The conflict dialog includes a unified diff. Red lines show the file on disk; green lines show your unsaved version.
  • Saving a file that changed on disk shows the same dialog instead of overwriting silently, whatever your external-changes setting.
  • File > Show Changes… opens the relevant comparison on demand — your unsaved edits, an incoming external change, or what the last reload brought in. It's dimmed only when there's nothing to show.

In every case you decide: Save My Changes keeps your version, Reload External Version keeps what's on disk, or cancel and keep editing.

Conflict Resolution

If a file changes on disk while you have unsaved edits in Peekdown, the banner warns you and Show Changes opens a conflict dialog with a diff of what changed, whatever your external-changes setting. This prevents accidentally losing your work.

File Deletion

If a file you have open is deleted, Peekdown prompts you to:

  • Save As… — Save your content to a new location
  • Close — Close the window
  • Keep Editing — Continue working (you can save later)