Selective sync

Use --include and --exclude (or the include/exclude config keys) to limit which relative paths are eligible for sync. Patterns use glob syntax and match paths relative to both local-root and remote-root.

proton-syncd \
  --local-root /tmp/proton-sync-demo \
  --remote-root /Drive/RemoteFolder \
  --include 'Documents/**' \
  --include 'Projects/**/*.md' \
  --exclude '**/*.tmp' \
  --exclude '**/.DS_Store' \
  --dry-run

The rules

Filters are applied consistently to local files, remote files, and existing index records before planning:

• With no include pattern, every non-ignored path is eligible.
• With one or more include patterns, only matching files are eligible.
• Exclude always wins over include.

Because the filters apply to the index too, an excluded record is never purged as a “missing” file — excluding a path takes it out of sync entirely, in both directions, without the engine deciding it was deleted. This is an important safety property.

Always ignored

Some paths are ignored regardless of your filters, so operational files never become sync data:

• Conflict sidecars (.proton-cloud) — so a kept-both file isn’t re-synced.
• The sync state directory <local-root>/.sync/ — the index DB, its .status.json and .metrics.json sidecars, and the lockfile. Only a top-level .sync is treated as state.
• A custom --db-path under the local root — so the index never becomes sync data.
• Download staging directories — any path component starting with .proton-sync-download-, so a partial download left by a crash is never uploaded.
• .proton-sync.toml at any depth — the machine-local per-directory settings files.

Confirm before enabling

Selective-sync mistakes are easy to make and easy to check. Run a dry-run after changing filters to confirm the eligible action set before you let the daemon sync for real:

proton-syncd --config proton-sync.toml --dry-run

In the desktop app

The app’s Settings → Selective sync section edits the raw include/exclude glob lists directly (add and remove patterns), and states the two rules that trip people up: exclude beats include, and .sync/ is always ignored. A checkbox-driven folder-tree view is planned but not yet available — it needs a directory-listing capability the daemon doesn’t expose today.