Upgrade to Node >v6

wget -qO- https://deb.nodesource.com/setup_6.x | sudo bash -
sudo apt-get install --yes nodejs

You can then install the latest npm, polymer-cli, and bower:

sudo npm install --global npm@latest
sudo npm install --global polymer-cli
sudo npm install --global bower

NEF processing uses ufraw-batch

sudo apt install ufraw-batch

Create photos user for DB

You will need to know the root password for your mariadb installation. If you need to reset the root password, you can perform the following:

export PASSWORD=m4g1cP4ssw0rd
sudo service mysql stop
sudo mysqld_safe --skip-grant-tables &
sleep 1 # mysqld_safe can take a bit of time to come online
sudo mysql << EOF
use mysql;
UPDATE user SET PASSWORD=PASSWORD("${PASSWORD}") WHERE USER='root';
UPDATE user SET plugin='mysql_native_password' WHERE USER='root';
FLUSH PRIVILEGES;
QUIT
EOF
sudo service mysql stop
sudo service mysql start

Once you know the root password, you can then create a new user and DB for the photo app via:

Create the USER

U='photos'
P='p4$$w0rd'
mysql -u root --password=${PASSWORD} << EOF
CREATE USER '${U}'@'localhost' IDENTIFIED BY '${P}';
EOF

Create the DB 'photos'

U='photos'
P='p4$$w0rd'
D='photos'
mysql -u root --password=${PASSWORD} << EOF
DROP DATABASE IF EXISTS ${D};
CREATE DATABASE ${D} CHARACTER SET utf8 COLLATE utf8_general_ci;
GRANT ALL PRIVILEGES ON ${D}.* TO '${U}'@'localhost' IDENTIFIED BY '${P}';
EOF