Imager is a version of the app that has been used in performance settings. Some recent developments are absent but it is pretty stable.
Imager-Alpha is a version of the Imager app that contains features that are currently under active development.
Imager Playground has simple versions of some of the Imager app’s key elements. It should prove useful in learning how those work and its code base may constitute an easier point of entry for new coders.
Draft Patchsets contains the most recent version of Fred’s doodling about.