If you’re in an environment where you have a lot of developers you’ll likely find the Homebrew command very close by, you can use this simple Extension Attribute in your Casper JSS to report on it:

#!/bin/sh
file="/Library/Caches/Homebrew" 
if [ -d "$file" ]
then
	echo "<result>"Present"</result>"
else
	echo "<result>"Not Present"</result>"
fi

Now you have your Homebrew check extension attribute why not turn it into a Smart Group and get smarter at targeting Mac’s that have Homebrew configured, to run certain commands in Self Service:

For example the wget command can only be configured on a Mac after Homebrew has been installed, so you can now target the wget command to run via a policy if the Mac meets the Smart Group “Has Homebrew Configured”