3 ms·

There are no other ones...

• orionblastar 14y ago
  The only thing that comes close is GNUStep: http://www.gnustep.org/ http://www.gnustep.org/ It won't run native OS X code, but you can compile code with Objective-C or other languages to run on GNUStep between Linux, Windows, and Mac OS X. It is based on NextStep, or OpenStep that Steve Jobs had at Next before Apple bought them out and turned it into Mac OS X.