Meteor is an open source platform for seamlessly building and deploying Web, Mobile, and Desktop applications in Javascript.
After registering an account is necessary to add payment method under settings → billing, because custom subdomain can be used only with non free application instances.
After installing, we can create new meteor application, I advise to use minimal template, because only minimal template doesn’t have mongodb dependency:
Meteor will create all the necessary files for us.
The files located in the client directory are setting up your client side (web), you can see for example client/main.html where we can change html to something more appropriate, like this with xss payload:
Now we can login and deploy our app:
DEPLOY_HOSTNAME must be same as subdomains cname
Meteor will deploy application and receive new https certificate for our subdomain.