Error when installing on osx and node 5.8 about zerorpc-node HOT 2 OPEN

I had a very similar error, Using nvm to control node versions I was using 4.2.2 and could be verified using:
$node -v
Nevertheless I noticed I had legacy node version at:
$nodejs -v
Which used node 0.10.25
Removing node 0.10.25 and creating a symbolic linc ln -s ... to have node 4.2.2 at $nodejs -v solver this issue. Haven't tested with node 5, but have had some compatibility issues where node 4.2.2 was required.
You can check if this solution applies to you

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There are two things happening here:

(1) you are missing msgpack dependency

npm install msgpack

(2) xcode-select: error: tool 'xcodebuild' requires Xcode, but active developer directory '/Library/Developer/CommandLineTools' is a command line tools instance

If you have XCode installed, which it looks like you do, run this to point xcodebuild to the right place

sudo xcode-select -s /Applications/Xcode.app/Contents/Developer

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