The Dangers of a “Walled Garden”
No one seriously argues against the viewpoint that Apple’s OS X provides
developers with a walled garden. While OS X runs Darwin under
the hood, it’s still very much a closed ecosystem. Even if you install
some third-party tools such as MacPorts or Homebrew, you’re
still fundamentally stuck with some of the options that Apple makes on
your behalf, very often in a “take it or leave it” way.
In the case of RVM, Ruby, and RubyGems, the walled garden has been
systematically weeding out standard compilers in favor of
LLVM-based compilers as provided by the 4.x series of Xcode.
In practice, that means many rubies and gems will not compile without
jumping through hoops—-and sometimes not even then. Even versions of
Ruby that will compile with LLVM may require gems that won’t, so this is
a non-starter for serious Ruby or Ruby on Rails development.
Luckily, even if you use a Mac on a regular basis, there’s hope. With a
little help from MacPorts, VirtualBox, and some exported compiler
settings, you can get a minimal Ruby environment running well enough to
bootstrap a Linux virtual machine that “just works” for Ruby