Create sudo user non-interactively

Skip the prompts that come with creating a user typically, and give them sudoers privileges. Replace ${USERNAME} with the user you want to create.

# The man page explanation for --gecos isn't that intuitive IMO
# Basically specifying --gecos "" states you don't want to ask
# for real name, phone, etc.
USERNAME=everythingisnormalhere
adduser --disabled-password --gecos "" "${USERNAME}"
touch "/etc/sudoers.d/10_${USERNAME}"
echo "${USERNAME} ALL=(ALL) NOPASSWD:ALL" > "/etc/sudoers.d/10_${USERNAME}"

Resources: https://askubuntu.com/questions/94060/run-adduser-non-interactively https://askubuntu.com/questions/420784/what-do-the-disabled-login-and-gecos-options-of-adduser-command-stand