https://ci.appveyor.com/project/HaxeFoundation/neko/build/artifacts
Note that you may need to install "Microsoft Visual C++ 2010 Redistributable Package" (x86), in case it complains MSVCR100.dll is missing.
brew install neko --HEAD.
Install the libgc-dev dependency, then build from source.
Install the devel/boehm-gc-threaded port or corresponding package, then build from source. See Makefile for additional instructions.