Frontend development failing to do a first build


I’m trying to set up my development environment following this guide:

I’m running on a Ubuntu 17.10
I’ve forked the home-assistant-polymer repository and cloned it to my station,
I’ve installed nvm,
I’ve installed yarn,
I did the nvm install and and nvm use as instructed,
when I’m trying to run the script script/bootstrap from the cloned directory and I get the following message:
ERROR: [Errno 2] No such file or directory: ‘install’.

Is there anything I’m doing wrong or anything I might be missing here?

Had to remove cmdtest before installing yarn.