Trayscale is an unofficial GTK4/Libadwaita desktop GUI for the Tailscale VPN daemon, targeting Linux (no official Linux GUI exists). It provides a system tray status icon, a full Libadwaita window for managing peers, exit nodes, Mullvad exit nodes, Taildrop file transfers, profiles, and connection state. The architecture is a single Go binary using gotk4 bindings to GTK4 and Libadwaita. It communicates with the local tailscaled via Tailscale's local API and IPN bus watcher for real-time status updates. The codebase demonstrates solid Go engineering: clean separation of concerns (tsutil client layer, UI layer, tray, datatypes), use of modern Go features (generics, iterators, slices, maps), and comprehensive tests for the core polling and search logic. While not a reusable library, several internal packages (peersearch, autosave, listmodels) are well-isolated and could be extracted.