A tool for making fat macOS binaries (a portable lipo)
You give it some executables, it makes a fat executable from them. The fat executable will run on any architecture supported by one of the input executables.
makefat <output file> <input file 1> <input file 2> ...
A tool for extracting fat macOS binaries (a portable lipo)
You give it some executable, it extracts the executables of any architecture in it.
extractfat <fat_file>