Keystone.js: Sending a template-based email using Mandrill from: https://gitter.im/keystonejs/keystone/archives/2015/01/15

index.js

//1. Set up your Mandrill credentials
keystone.init({
    // ...
    'mandrill api key': 'YOUR_API_KEY_HERE',
    // ...
    'emails': 'templates/emails',
});

//or alternatively, you can set the key later
keystone.set('mandrill api key', 'YOUR_API_KEY_HERE');

//2. sending an email
//Note: the setup assumes that you have a template file called
//'enquiry-notification.{TEMPLATE_EXTENSION, e.g. .hbs, .jade}'
//in '/templates/emails'
new keystone.Email('enquiry-notification').send({
    subject: 'New Enquiry from Yoga Australia Website',
    to: 'name@server.com',
    fromName: 'From Name',
    fromEmail: 'from@server.com',
    // other locals for the email template also go here
}, callback);