安装 yarn
Yarn package manager for nodejs modules (an alternative to npm) is available as yarnpkg package and yarnpkg command (this change is due to a file conflict with cmdtest package which was providing yarn command already).
# apt install yarnpkg
$ yarnpkg --version
If you want to use yarn command (for example if you want to use other tools which look for yarn command), you can add a symbolic link.
# ln -s /usr/bin/yarnpkg /usr/bin/yarn
https://github.com/yarnpkg/yarn/