echo -n 'virtualenv: '
virtualenv --version \
|| fatal "No virtualenv. Try: apt-get install virtualenv (on ubuntu: python-virtualenv)"
+ echo -n 'ruby: '
+ ruby -v \
+ || fatal "No ruby. Install >=2.1.9 (using rbenv, rvm, or source)"
+ echo -n 'bundler: '
+ bundle version \
+ || fatal "No bundler. Try: gem install bundler"
echo -n 'go: '
go version \
|| fatal "No go binary. See http://golang.org/doc/install"