The duo command

The same engine has a command line. duo links the real DuoUpdaterCore, so it uses the same sources in the same order, the same install policy, and the same ignore and skip rules as the menu bar — a disagreement between the two is a bug, not a difference of opinion.

make cli          # → ~/.local/libexec/duo, symlinked at ~/.local/bin/duo

duo list                     # what's installed, without touching the network
duo check --json             # what has an update, one JSON object per line
duo install Cursor           # apply one, or --all
duo doctor                   # whether this machine can actually install anything
duo backups                  # list rollback points, or put one back

duo check and duo list also take --source sparkle,github,… and --include-hidden. duo ignore and duo skip write the same preferences the app reads, so hiding something in one hides it in the other.

Two things it refuses rather than half-doing

App Store updates. That route needs either the privileged helper — whose SMAppService registration requires an app bundle — or the Accessibility API driving App Store.app. A command-line tool has neither, so it says so instead of failing part-way through.

Taking the install lock by force. If the menu-bar app is mid-install, duo exits and names the holder rather than swapping a bundle out from underneath it.

The maintenance side

duo verify, duo triage and duo reconcile sweep every hand-written recipe against its live endpoint, ask a model why a broken one broke, and turn the result into issues. That is what the nightly check runs. They are not needed for ordinary use.