Folks, after a lot of hard work over the past two months, I'm pleased to announce that MacPorts now provides up-to-date binary builds of Mame! Those are available across a very wide range of macOS versions, from 10.6 through Big Sur. We even provide an M1-native binary for the latter.

The latest Mame release - 0.227 - is supported for macOS 10.14+. While earlier macOS versions are just one release behind, at 0.226.

We provide a full build for the core Mame application, and also include the command-line tools.

If you're interested in taking it for a spin, it's easy: Install MacPorts if necessary, and then run the following from Terminal:
sudo port install mame

Once the installation is completed, some brief usage notes will be displayed:
mame has the following notes:
  Mame is launched via command 'mame'.
  If a blank screen is encountered, press ESC to exit, and then re-launch with an
  alternative video option.
      mame -video accel
      mame -video opengl
  If you're new to Mame, our tutorial will quickly walk you through the process of
  setting up a new game:
  Mame tools are installed. Each has a prefix of 'mame-', to avoid conflicts with
  system tools.

The 'mame' command is backed by a simple launcher script, which sets a few critical paths for proper operation. (Including languages, plugins, bgfx, and several others.) Those can be overridden by specifying them yourself, if desired.

Otherwise, Mame operates just as you'd expect.

Give it a try, and please feel free to provide feedback... positive or negative.

Cheers and Thanks,
-Chris Nielsen
MacPorts Mame Maintainer