https://github.com/LLK/scratch-gui/wiki/Getting-Started#example-scratch-gui-vm-and-blocks-linked
mkdir scratch && cd scratch
git clone https://github.com/aubrune/scratch-gui # if making changes fork the project and check out your copy
git clone https://github.com/aubrune/scratch-vm # if making changes fork the project and check out your copy
git clone https://github.com/aubrune/scratch-blocks # if making changes fork the project and check out your copy
cd scratch-vm
npm install
sudo npm link