"Templates as a service", or "temperaas", changed to "temperos" later because it was a nice pun in Portuguese.
The ideas was that it would take an URL with any file and some querystring parameters, then replace {{paramName}} with the parameters from the querystring and serve it, all stateless.
Created to make it easy for people to embed scripts on Websites For Trello (but of course it was too hard for most people).