OS X apps installed via Homebrew Cask can have a "zap" command defined that will automate a deep uninstall:

`brew cask zap <app_name>`

It isn't an acceptable answer for the average Mac user, but it at least solves the issue for a subset of users.

The majority of MacPorts programs I installed over the years uninstalled cleanly.

Also I could be wrong but isn't/wasn't the whole "fat binaries + static binaries + app binary and its associated assets live in a magic folder that the OS-X GUI displays as 'the app' + other past Mac app trickery such as resource forks etc" all meant to make both app install and UN-install painless and easy ?

I know and used a few commercial apps that were a damn pain to scrub completely off the Macs I owned but that was expensive proprietary commercial software that felt the need to take my money and also saddle me with DRM to enforce their licensing.

Not all Mac apps are of the "drag to your /Applications folder" variety. Some still come with an installer they expect you to run, and prompt you for admin rights.

Probably inspired by AppZapper which does a great job of addressing the problem

This app seems to have a bit more complication than most, due to tapping into the operating system more deeply (I presume).

But for most apps I've found AppCleaner to work very well for uninstalling all related files (regardless of where they're scattered about): https://freemacsoft.net/appcleaner/

AppCleaner works great. I also recommend it.

I think Steam installs a daemon that watches for game aliases being dragged into the Trash, and then deletes their locally installed content.

Maybe Apple could provide a builtin mechanism in MacOS (as I assume/hope it's about to be called) that watches for a .app bundle being dragged into the Trash, and offers the user a chance to remove any auxiliary files created by that app, and run its uninstallation scripts if any, when the Trash is being emptied?

Of course it will have to be seamless and resistant to developer abuse (or malice) and not make everything too Windows'y.

That facility sort of exists for sandboxed Mac apps, since all incidental files related to the app are under a single container that iirc is deleted if the corresponding app is removed.

Ah then "uninstallation" isn't needed at all, unless it pumps a lot of stuff into ~/Library/Application Support or somewhere, kind of like what Xcode does (I think it forgets about outdated and huge documentation downloads sometimes.)

http://www.macupdate.com/app/mac/10051/uninstaller is the best solution I've found so far. With Uninstaller you scan the whole system drive before installation. After installation is ready you do a "compare" scan. You will now see all the new and modified files. This is list saved as a file for later removal of the installed software.

Too bad it is abandoned software, but it still works terrific.