Dotenv-Mustache integrates the lovely Mustache templating language into dotenv. This would allow for the creation of dynamic environment variables.
npm install dotenv --save
npm install dotenv-mustache --save
At the entry point of your application, you should require dotenv and dotenv-mustache, and call it into you code as follows.
var dotenv = require('dotenv')
var dotMustache = require('dotenv-mustache')
var myEnv = dotenv.config()
dotMustache(myEnv)
See test/.env for examples of mustache expressions in environment variables.