fileicon is a tiny Swift script that makes it easy to set custom icons on files and directories in macOS.
It's designed primarily for use in automated software build and packaging workflows.
If you want a compiled version, run make and copy the resulting
fileicon binary to somewhere in your $PATH.
Alternatively, if you want to use fileicon in your build process without
having to deal with compiling it, you can just rename main.swift to
fileicon, copy it into your source tree and take advantage of Swift's
#! support by running it directly as a script.
$ fileicon set FILE-PATH ICON-PATH
fileicon currently does not offer any way to remove an icon once it's been set. There is no equivalent call in the Cocoa API to do this; it would require direct manipulation of the file's resource fork.