Major The Jenkins installer .pkg provided at http://mirrors.jenkins-ci.org/osx/latest installs Jenkins as a service, but provided no uninstall script or instructions. There appears to be an uninstall script at https://issues.jenkins-ci.org/browse/JENKINS-11776 .
Could you include, in the install, this uninstall script or some other clearly visible way of uninstalling Jenkins?
[JENKINS-16289] Please bundle uninstaller with Jenkins Mac install
David Stark
added a comment - Thanks for your reply! I think it would be much better to put it under /Applicatons/Jenkins. /Library/Application Support is more a general-purpose storage area where Mac programs can put data, and so I didn't even think to check there. In fact, under OS X Lion, the user's Library folder is hidden by default.
The best option IMO would be to make the download a disk image that contains both the installer .pkg and the uninstaller program. This way, the installing-related options are bundled together on the same level and visible at the same time.
David Stark
added a comment - Thanks for your reply! I think it would be much better to put it under /Applicatons/Jenkins. /Library/Application Support is more a general-purpose storage area where Mac programs can put data, and so I didn't even think to check there. In fact, under OS X Lion, the user's Library folder is hidden by default.
The best option IMO would be to make the download a disk image that contains both the installer .pkg and the uninstaller program. This way, the installing-related options are bundled together on the same level and visible at the same time. 
The Mac version of Jenkins comes with an uninstaller. You can find it in folder /Library/Application Support/Jenkins. I admit it is a fairly new addition and was added only 6 months ago.
Maybe the location of the uninstaller could be improved? I did consider placing it under /Applications/Jenkins but that isn't very usual for Mac software. Additionally, I used to make Mac software for a living and I had placed the uninstaller in the same directory with the application. Still, a frequently asked question in customer support was: "How do I uninstall this?"