Hacking: Building/Mac OSX
From GIMP Developer Wiki
Current procedure
GIMP has an official build whose scripts are located at this repo: https://gitlab.gnome.org/Infrastructure/gimp-macos-build
Historical links
Some older links explain how to build and install GIMP on an Apple computer running the OSX operating system. We are not sure how acceptable they are with current code.
One person describes how to build Gimp on OSX using native gtk-osx and the jhbuild tool.