First off you need Apple's Xcode (at least version 7, preferably 8.x) and the Xcode Command Line Tools:
https://itunes.apple.com/us/app/xcode/id497799835?mt=12
And Homebrew:
And this is the list of brew packages you'll need installed:
brew tap discoteq/discoteq; brew install flock
brew install autoconf autogen automake
brew tap homebrew/versions; brew install homebrew/versions/gcc5
brew install binutils
brew install protobuf
brew install coreutils
brew install wget
Get all that installed, then run:
git clone https://github.com/j-cimb-barker/komodo.git
cd komodo
git checkout dev
./zcutil/build-mac.sh
To build a distributable version of komodo then run the makeDistrib.sh script after building.
When you are done building, you need to do a few things in the Configuration section of the Zcash User Guide differently because we are on the Mac. All instances of ~/.zcash
need to be replaced by ~/Library/Application\ Support/Zcash
The fetch-params.sh script, however, has already been altered to fetch the proving keys into the correct directory to conform to Mac specific naming conventions.
Happy Building