don't hardcode the Cellar path, use the env variable

[i3d]

This would work always for various different installation configurations. It even works for Homebrew for other platforms like linuxbrew.

[13-CF]

Is changing the install to ~/.local a good idea? I don't think ~/.local/bin is in $PATH by default on lots of systems.

[kdx2a]

Is changing the install to ~/.local a good idea? I don't think ~/.local/bin is in $PATH by default on lots of systems.

It's a bad idea. If you want to overwrite the install path with something less standard than /usr/local, call make with a specified PREFIX:

$ make install PREFIX="$HOME"/.local
$ make uninstall PREFIX="$HOME"/.local

[Jan200101]

I suggest not printing an error message when the Cellar ENV var is not found and simply falling back to the original behavior