<b_jonas> slashlearn farbfeld//zzo38\'s Farbfeld utilities is a package of command-line programs (with rather strange command-line syntax) for manipulating images in a specific raw format called farbfeld. It\'s somewhat underdocumented. http://zzo38computer.org/fossil/farbfeld.ui/home

composition is where you take morphisms such as Phantom and Hoover from the Pha category and combine them together: Hoover ∘ Phantom.