Add a user to sudo group

usermod -aG sudo <username>

Count files recursively in a directory

find <directory> -type f | wc -l

Also suppress permission denied errors:

find <directory> -type f 2> /dev/null | wc -l

Reference Articles

Installing node / yarn on Ubuntu 18

https://linuxize.com/post/how-to-install-yarn-on-ubuntu-18-04/

• For nodejs, sudo apt-get install nodejs gets you node8 (which is old)
• So, need curl -sL https://deb.nodesource.com/setup_10.x | sudo -E bash -
• which leads us to yarn curl -sL https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add - echo "deb https://dl.yarnpkg.com/debian/ stable main" | sudo tee /etc/apt/sources.list.d/yarn.list
• sudo apt-get update && sudo apt-get install yarn
• sudo apt-get install -y nodejs