What "seen" means

When an AI agent rewrites a file, you want to know what it changed since you last looked. Skimmark keeps a copy of each file as you last saw it. That copy is the file's seen version.

When Skimmark saves the seen version

• The first time you open a file, Skimmark saves the version it shows you as the seen version.
• When you mark it seen, Skimmark replaces it with the version on your screen: see Mark as seen.
• Later opens and live updates do not replace it. If an agent changes the file while you read, the seen version stays the one from before.
• Closing a tab does not change it. Neither does quitting Skimmark.

Skimmark saves the file exactly as it is on disk, byte for byte, including line endings. Files over 20 MB are not saved.

If you open the same file under another name that points to it (a symbolic link, or on Windows the same path typed in different upper and lower case), Skimmark treats it as the same file and keeps one seen version.

See and clear what changed

To see what changed since the seen version, turn on Changes: see Seeing what changed. To accept what you see as the new seen version, press Seen: see Mark as seen.

Where seen versions live

Skimmark keeps seen versions in a snapshots folder inside its own app data folder, never next to your files:

Each seen version is one file with a long random-looking name. index.json in the same folder lists which file each one belongs to and when it was saved.

Privacy

Seen versions stay on this computer. Skimmark does not upload them or send them anywhere.

They are full copies of your files, so they hold whatever your files hold. To remove them all, quit Skimmark and delete the snapshots folder. The next time you open a file, Skimmark starts again from the version it shows you.