When setting up your server you'll be asked for the "connect as" user. This is the user Ottomatik will use to make an SSH connection to your server with. It is not necessary for this user to be root or to have sudo privileges provided the installation dependencies are met.
Ottomatik will check the dependencies below and if they are not present it will attempt to install them. In that case sudo will be required to install the components. If they are present, any installation will be skipped. The sudo privilege is not required to run a backup if you have presiously installed the dependencies manually:
You may find additional notes on manually installing these components as well as some installation commands here.