This is super cool. Are there any demonstrations comparing performance between electron and your app?
It seems to runs on "UI" from andlabs, which is a fairly lightweight C wrapper around the the Windows, Cocoa and Gtk API's. Sidenote as for why a UI library would wrap another UI wrapping library, Gtk is what is considered "native" on Gnome based distros. So weight-wise, it's basically comes at the cost of native node module which is not bad compared to Electron's crazy IPC bridge back and forth communication nonsens…
And now with NAPI [1] it should be easier than ever to make node modules!