Ruby Packaging on OS X

Julian Raschke edited this page Jan 20, 2017 · 3 revisions

Ruby Packaging on OS X

Do you want to share your game with other Mac users? Simply follow these steps:

  • Find the most recent Mac app wrapper on github
  • Show the app’s package contents via the right-click menu in Finder
  • Edit the Info.plist file, and change the bundle identifier to match your game (org.libgosu.UntitledGame by default)
  • Copy your game files into the Contents/Resources subfolder
  • Rename your game’s main source file to Main.rb

And you’re done! You should now have a fully functional .app bundle.

The .app is a self-contained Ruby installation with most of the standard library, plus a few libraries that are often used together with Gosu.

Using Releasy

There is a relatively rough (unmaintained) gem that can handle the packaging for you:

It really does nothing else than to automate the process outlined above.


  • If the app does not start, the macOS Console app is your friend. Open it using Spotlight, start your game and look for any errors that appear.
  • If Console does not show enough information, open a Terminal and cd into the same directory in which the .app file is located. Then run
  • If it seems that everything is correct, but the app still does not start, try compressing it into a .zip file, deleting the .app, and unpacking the .zip file again. This will force macOS to forget any information that it may have cached about the app. (This is sometimes necessary for macOS to recognise changes made to the Info.plist file.)
  • Using bundler is a little hairy because the structure of the .app folder predates its existence. You might need to ask on the forum, or use releasy which understands bundler.
  • If you need to use libraries that are not included in the .app, copy them into the lib folder. If you need C extensions that are not included in the .app, you should ask on the Extending Gosu board or on reddit.